H. A. Yildiz, A. Toker, S. Ozoguz [references] [full-text] [Download Citations]
Biquadratic Filter Applications Using a Fully-Differential Active-Only Integrator

A new class of active filters, real active-only filters is described and possible implementation issues of these filters are discussed. To remedy these issues, a fully-differential active-only integrator block built around current controlled current conveyors is presented. The integration frequency of the proposed circuit is adjustable over a wide frequency range. As an application, a real active-only filter based on the classical two-integrator loop topology is presented and designed. The feasibility of this filter in a 0.35µm CMOS process is verified through SPECTRE simulation program in the CADENCE design tool.

1. SOLIMAN, A. M., FAWZY, M. A new active R bandpass filter. Journal of the Franklin Institute, 1978, vol. 306, p. 159 - 163.
2. BRAND, J. R., SCHAUMANN, R. Active R filters: review of theory and practice. Electronic Circuits and Systems, 1978, vol. 2, p. 89 - 101.
3. TSUKUTANI, T., HIGASHIMURA, M., SUMI, Y., FUKUI, Y. Voltage-mode active-only biquad. International Journal of Electronics, 2000, vol. 87, p. 1435 - 1442.
4. TSUKUTANI, T., HIGASHIMURA, M., TAKAHASHI, N., SUMI, Y., FUKUI, Y. Novel voltage-mode biquad using only active devices. International Journal of Electronics, 2001, vol. 88, p. 339 - 346.
5. TSUKUTANI, T., HIGASHIMURA, M., KINUGASA, Y. N., SUMI, Y., FUKUI, Y. Novel voltage-mode active-only biquad with two integrator loops. In Proceedings of International Technical Conference on Circuits / Systems, Computers and Communications (ITC-CSCC). Pusan (Korea), 2000.
6. TSUKUTANI, T., SUMI, Y., FUKUI, Y. Electronically tunable current-mode OTA-C biquad using two-integrator loop structure. Frequenz, 2006, vol. 60, p. 53 - 56.
7. PROMMEE, P., KUMNGERN, M., DEJHAN, K. Current mode active-only universal filter. In IEEE Asia-Pacific Conference on Circuits and Systems (APCCAS). Singapore, 2006, p. 896 - 899.
8. MINAEI, S., CICEKOGLU, O., KUNTMAN, H., TURKOZ, S., Electronically tunable, active floating inductance simulation. International Journal of Electronics, 2002, vol. 89, p. 905 - 912.
9. ALLEN, P. E., HOLBERG, R. D. CMOS Analog Circuit Design. New York (USA): Oxford University Press, 2002.
10. FABRE, A., SAAID, O., WIEST, F., BOUCHERON C., High frequency applications based on a new current controlled conveyor. IEEE Transactions on Circuits and Systems I: Fundamental Theory and Applications, 1996, vol. 43, no. 2, p. 82 - 91.
11. YILDIZ, H. A., TOKER, A., OZOGUZ, S. On the design and implementation of real active-only filters. In 35th International Conference on Telecommunication and Signal Processing. Prague (Czech Republic), 2012, p. 369 - 373.
12. RINCON-MORA, G. A. Active capacitor multiplier in Millercompensated circuits. IEEE Journal of Solid-State Circuits, 2000, vol. 35, no. 1, p. 26 - 32.
13. BRUUN, E., CMOS high speed, high precision current conveyor and current feedback amplifier structures. International Journal of Electronics, 1993, vol. 74, p. 93 - 100.
14. FABRE, A., SAAID, O., BARTHELEMY, H. On the frequency limitation of the circuits based on second generation current 1995, vol. 7, p. 113 - 129.
15. RAZAVI, B. Design of Analog CMOS Integrated Circuits. New York (USA): McGraw-Hill, 2000.
16. MINAEI, S., TOPCU, G., CICEKOGLU, O. Active only integrator and differentiator with tunable time constants. International Journal of Electronics, 2003, vol. 90, p. 581 - 588.
17. METIN, B., ARSLAN, E., HERENCSAR, N., CICEKOGLU, O. Voltage-mode MOS-only all-pass filter. In 34th International Conference on Telecommunications and Signal Processing (TSP). Budapest (Hungary), 2011, p. 317 - 318.
18. YILDIZ, H. A., OZOGUZ, S., TOKER, A., CICEKOGLU, O., On the realization of MOS-only allpass filters. Circuits, Systems, and Signal Processing, 2012, DOI: 10.1007/s00034-012-9500-4.
19. SINGH, A. K., SENAI, R, BHASKAR, D. R., SHARMA, R. K., A new electronically-tunable active-only universal biquad. Journal of Circuits, Systems, and Computers, 2011, vol. 20, p. 549 - 555.

Keywords: Active-only filters, current controlled current conveyors, analog filter design

P. Prommee, N. Wongprommoon [references] [full-text] [Download Citations]
Log-domain All-pass Filter-based Multiphase Sinusoidal Oscillators

Log-domain current-mode multiphase sinusoidal oscillators based on all-pass filters are presented in this paper. The first-order differential equation is used for obtaining inverting and non-inverting all-pass filters. The proposed oscillators are realized by all-pass filters which can be electronically tuned their natural frequency and stage gain by adjusting the bias currents. Each all pass filter contains 10 NPN transistors and a grounded capacitor. The validated BJT model which used in SPICE simulation operated by a single power supply as low as 2.5 V. The frequency of oscillation can be controlled over four decades. The total harmonic distortions of these MSO at frequency 56.67 MHz and 54.44 MHz, obtained around 0.52% and 0.75%, respectively. The proposed circuits enable fully integrated in telecommunication systems and also suit to high-frequency applications. Nonideality studies and PSpice simulation results are included to confirm the theory.

1. ADAMS, R. W. Filtering in the log domain. In 63rd AES Conv., Los Angeles (CA), May 1979, preprint 1470.
2. FREY, D. R. Log-domain filtering: An approach to current-mode filtering. Proc. IEE, part-G, 1993, vol. 140, no. 6, p. 406–416.
3. FREY, D. R. Exponential state-space filters: a generic current mode design strategy. IEEE Trans Circuits Systems-I, 1996, vol. 43, p. 34–42.
4. SEEVINCK, E. Companding current-mode integrator: A new circuit principle for continuous-time monolithic filters. Electron. Lett., 1990, vol. 26, no. 24, p. 2046–2047.
5. TSIVIDIS, Y. On linear integrators and differentiators using instantaneous companding. IEEE Trans. Circuits Syst. II, Aug.1995, vol. 42, p. 561–564.
6. TSIVIDIS, Y. General approach to signal processors employing companding. Electron. Lett., 1995, vol. 31, no. 18, p. 1549–1550.
7. FREY, D. R., TSIVIDIS, Y. Syllabically companding log domain filter using dynamic biasing. Electron. Lett., 1997, vol. 33, no. 18, p. 1506-1507.
8. FREY, D. R. A 3.3 V electronically tuneable active filter useable to beyond 1 GHz. In Proc. IEEE Int. Symp. Circuits Syst. (ISCAS’94). London (U.K.), 1994, vol. 5, p. 493–496.
9. FREY, D. R. Log domain filtering for RF applications. IEEE J. Solid-State Circuits, Oct. 1996, vol. 31, p. 1468–1475.
10. FREY D. R. An adaptive analog notch filter using log-filtering. In Proc. IEEE Int. Symp. Circuits Syst. (ISCAS’96). Atlanta (GA), 1996, vol. 1, p. 297–300.
11. YANG, F., ENZ, C., RUYMBEKE, G. Design of low-power and low voltage log-domain filters. In Proc. IEEE Int. Symp. Circuits Syst.(ISCAS’96). Atlanta (GA), 1996, vol. 1, p. 117–120.
12. DRAKAKIS, E. M., PAYNE A. J., TOUMAZOU, C. Log-domain filtering and the Bernoulli cell. IEEE Trans. Circuits Syst. I, May 1999, vol. 46, no. 5, p. 559–571.
13. EL-GAMAL, M. N., ROBERTS, G. W. A 1.2-V n-p-n-only integrator for log-domain filtering. IEEE Trans. Circuits Syst. II, Apr. 2002, vol. 49, p. 257-265.
14. DRAKAKIS, E. M., PAYNE, A. J., TOUMAZOU, C. Log-domain state-space: A systematic transistor level approach for log-domain filtering. IEEE. Trans. Circuits Syst. II, Mar. 1999, vol. 46, p. 290 to 305.
15. PYTHON, D., ENZ, C. A micropower class-AB CMOS logdomain filter for DECT applications. IEEE J. Solid-State Circuits, July 2001, vol. 36, no. 7, p. 1067-1075.
16. WU, D., LIU, S., HWANG, Y., WU, Y. Multiphase sinusoidal oscillator using second-generation current conveyors. International Journal of Electronics, 1995, vol. 78, p. 645–651.
17. ABUELMA’ATTI, M. T., AL-QAHTANI, M. A. A new currentcontrolled multiphase sinusoidal oscillator using translinear current conveyors. IEEE Transactions on Circuits and Systems-II, 1998, vol. 45, no. 7, p. 881-885.
18. PROMMEE, P., DEJHAN, K. An integrable electronic-controlled quadrature sinusoidal oscillator using CMOS operational transconductance amplifier. International Journal of Electronics, 2002, vol. 89, no. 5, p. 365-379.
19. GIFT, S. J. G. The application of AP filters in the design of multiphase sinusoidal systems. Micro-electronics Journal, 2000, vol. 31, p. 9–13.
20. TANGSRIRAT, W., TANJAROEN, W., PUKKALANUN, T. Current-mode multiphase sinusoidal oscillator using CDTA-based allpass sections. Int. J. Electron. Commun. (AEU), 2009, vol. 63, p. 616 – 622.
21. JAIKLA, W., PROMMEE, P. Electronically tunable current-mode multiphase sinusoidal oscillator employing CCCDTA-based allpass filters with only grounded passive elements. Radioengineering, 2011, vol. 20, no. 3, p. 594-599.
22. PSYCHALINOS, C., SOULIOTIS, G. A log-domain multiphase sinusoidal oscillator. AEU - International Journal of Electronics and Communications, 2008, vol. 62, no. 8, p. 622-626.
23. SERDIJN, W. A., MULDER, J., KOUWENHOVEN, M. H. L., VAN ROERMUND, A. H. M. A low-voltage translinear secondorder quadrature oscillator. In Proc. IEEE Int. Symp. Circuits Syst (ISCAS’99). Orlando (Florida, USA), 1999, vol.2, p. 701-704.
24. PROMMEE, P., SRA-IUM, N., DEJHAN, K. High-frequency logdomain current-mode multiphase sinusoidal oscillator. IET Circuits Devices Syst., Sep. 2010, vol. 4, no. 5, p. 440–448.
25. PROMMEE, P., PRAPAKORN, N., SWAMY, M. N. S. Log-domain current-mode quadrature sinusoidal oscillator. Radioengineering, 2011, vol. 20, no. 3, p. 600-607.
26. PROMMEE, P., SOMDUNYAKANOK, M. Log-domain all-pass based multiphase sinusoidal oscillator. In Proc. of IEEE TSP2012. Prague (Czech Republic), July 3-4, 2012, p. 355 - 358.
27. GILBERT, B. Translinear circuits: an historical overview. Analog Integrated Circuits and Signal Processing, Mar. 1996, vol. 9, no. 2, p. 95-118.
28. LEUNG, V. W., ROBERTS, G. W. Effects of transistor nonidealities on high-order log-domain ladder filter frequency responses. IEEE Trans. Circuits Syst. II, 2000, vol. 47, no. 5, p. 373-387.

Keywords: All-pass filter, log-domain filtering, high-frequency, low-voltage, electronically-controlled, Multiphase Sinusoidal oscillator

M. Sagbas, U. E. Ayten, N. Herencsar, S. Minaei [references] [full-text] [Download Citations]
Current and Voltage Mode Multiphase Sinusoidal Oscillators Using CBTAs

Current-mode (CM) and voltage-mode (VM) multiphase sinusoidal oscillator (MSO) structures using current backward transconductance amplifier (CBTA) are proposed. The proposed oscillators can generate n current or voltage signals (n being even or odd) equally spaced in phase. n+1 CBTAs, n grounded capacitors and a grounded resistor are used for nth-state oscillator. The oscillation frequency can be independently controlled through transconductance (gm) of the CBTAs which are adjustable via their bias currents. The effects caused by the non-ideality of the CBTA on the oscillation frequency and condition have been analyzed. The performance of the proposed circuits is demonstrated on third-stage and fifth-stage MSOs by using PSPICE simulations based on the 0.25 µm TSMC level-7 CMOS technology parameters.

1. GIFT, J. S. G. Multiphase sinusoidal oscillator system using operational amplifiers. International Journal of Electronics, 1997, vol. 83, no. 1, p. 61 - 67.
2. GIFT, J. S. G. Multiphase sinusoidal oscillator using invertingmode operational amplifiers. IEEE Transactions on Instrumentation and Measurement, 1998, vol. 47, no. 4, p. 986 to 991.
3. MAUNDY, B., ELWAKIL, A., GIFT, S. On the realization of multiphase oscillators using fractional-order allpass filters. Circuits, Systems, and Signal Processing, 2012, vol. 31, no. 1, p. 3 - 17.
4. HOU, C. L., SHEN, B. Second-generation current conveyor-based multiphase sinusoidal oscillators. International Journal of Electronics, 1995, vol. 78, no. 2, p. 317 - 325.
5. WU, D.-S., LIU, S.-I., HWANG, Y.-S., WU, Y.-P. Multiphase sinusoidal oscillator using second-generation current conveyors. International Journal of Electronics, 1995, vol. 78, no. 4, p. 645 to 651.
6. ABUELMA'ATTI, M. T., AL-QAHTANI, M. A. Low component second generation current conveyor-based multiphase sinusoidal oscillator. International Journal of Electronics, 1998, vol. 84, no. 1, p. 45 - 52.
7. SKOTIS, G. D., PSYCHALINOS, C. Multiphase sinusoidal oscillators using second generation current conveyors. AEU - International Journal of Electronics and Communications, 2010, vol. 64, no. 12, p. 1178 - 1181.
8. TANGSRIRAT, W., TANJAROEN, W. Current-mode multiphase sinusoidal oscillator using current differencing transconductance amplifiers. Circuits, Systems, and Signal Processing, 2008, vol. 27, no. 1, p. 81 - 93.
9. TANGSRIRAT, W., TANJAROEN, W., PUKKALANUN, T. Current-mode multiphase sinusoidal oscillator using CDTA-based allpass sections. AEU - International Journal of Electronics and Communications, 2009, vol. 63, no. 7, p. 616 - 622.
10. JAIKLA, W., SIRIPRUCHYANUN, M., BIOLEK, D., BIOLKOVA, V. High-output-impedance current-mode multiphase sinusoidal oscillator employing current differencing transconductance amplifier-based allpass filters. International Journal of Electronics, 2010, vol. 97, no. 7, p. 811 - 826.
11. LI, Y. A novel current-mode multiphase sinusoidal oscillator using MO-CDTAs. International Journal of Electronics, 2012, vol. 99, no. 4, p. 477 - 489.
12. JAIKLA, W., PROMMEE, P. Electronically tunable current-mode multiphase sinusoidal oscillator employing CCCDTA-based allpass filters with only grounded passive elements. Radioengineering, 2011, vol. 20, no. 3, p. 594 - 599.
13. PISITCHALERMPONG, S., TANGSRIRAT, W., SURAKAMPONTORN, W. CDBA-based multiphase sinusoidal oscillator using grounded capacitors. In Proceeding of the SICE-ICASE International Joint Conference. Bexco, Busan (Korea), 2006, p. 5762 - 5765.
14. SOULIOTIS, G., PSYCHALINOS, C. Electronically controlled multiphase sinusoidal oscillators using current amplifiers. International Journal of Circuit Theory and Applications, 2009, vol. 37, no. 1, p. 43 - 52.
15. PROMMEE, P., SRA-IUM, N., DEJHAN, K. High-frequency logdomain current-mode multiphase sinusoidal oscillator. IET Circuits Devices & Systems, 2010, vol. 4, no. 5, p. 440 - 448.
16. UTTAPHUT, P. New current-mode multiphase sinusoidal oscillators based on CCCCTA-based lossy integrators. Przeglad Elektrotechniczny, 2012, vol. 88, no. 1A, p. 291 - 295.
17. KUMNGERN, M., CHANWUTITUM, J., DEJHAN, K. Electronically tunable multiphase sinusoidal oscillator using translinear current conveyors. Analog Integrated Circuits and Signal Processing, 2010, vol. 65, no. 2, p. 327 - 334.
18. AYTEN, U. E., SAGBAS, M., SEDEF, H. Current-mode leapfrog ladder filter using a new active block. AEU - International Journal of Electronics and Communications, 2010, vol. 64, no. 6, p. 503 to 511.
19. SAGBAS, M., AYTEN, U. E., SEDEF, H. Current and voltage transfer function filters using a single active device. IET Circuits Devices & Systems, 2010, vol. 4, no. 1, p. 78 - 86.
20. KOKSAL, M., AYTEN, U. E., SAGBAS, M. Realization of new mutually coupled circuit using CC-CBTAs. Circuits, Systems, and Signal Processing, 2012, vol. 31, no. 2, p. 435 - 446.
21. KOKSAL, M. Realization of a general all-pole current transfer function by using CBTA. International Journal of Circuit Theory and Applications, Published online on 10 Oct. 2011. DOI: 10.1002/cta.806
22. AYTEN, U. E., SAGBAS, M., HERENCSAR, N., KOTON, J. Novel floating FDNR, inductor and capacitor simulator using CBTA. In Proceeding of 2011 34th International Conference on Telecommunications and Signal Processing (TSP 2011). Budapest (Hungary), 2011, p. 312 - 316.
23. SAGBAS, M. Component reduced floating ±L, ±C and ±R simulators with grounded passive components. AEU - International Journal of Electronics and Communications, 2011, vol. 65, no. 10, p. 794 - 798.
24. HERENCSAR, N., LAHIRI, A., KOTON, J., SAGBAS, M., AYTEN, U. E., VRBA, K. New MOS-C realization of transadmittance type all-pass filter using modified CBTA. In Proceeding of International Conference on Applied Electronics (AE 2011). Pilsen (Czech Republic), 2011, p. 153 - 156.
25. HERENCSAR, N., KOTON, J., VRBA, K., LAHIRI, A., AYTEN, U. E., SAGBAS, M. A new compact CMOS realization of sinusoidal oscillator using a single modified CBTA. In Proceeding of 21st International Conference Radioelektronika. Brno (Czech Republic), 2011, p. 41 - 44.
26. AYTEN, U. E., SAGBAS, M., SEDEF, H. Electronically tunable sinusoidal oscillator circuit with current and voltage outputs. International Journal of Electronics, 2012, vol. 99, no. 8, p. 1133 to 1144.
27. AYTEN, U. E., SAGBAS, M., HERENCSAR, N., KOTON, J. Novel floating general element simulators using CBTA. Radioengineering, 2012, vol. 21, no. 1, p. 11 - 19.
28. MILLMAN, J., HALKIAS, C. C. Integrated Electronics. New York: McGraw-Hill, 1972.
29. SAGBAS, M., AYTEN, U. E., HERENCSAR, N., MINAEI, S. Voltage-mode multiphase sinusoidal oscillators using CBTAs. In Proceedings of the 2012 35th International Conference on Telecommunications and Signal Processing (TSP 2012). Prague (Czech Republic), 2012, p. 421 - 425.

Keywords: Multiphase sinusoidal oscillator, current backward transconductance amplifier (CBTA), current-mode circuits, voltage-mode circuits, active networks.

A. Ambede, K. G. Smitha, A. P. Vinod [references] [full-text] [Download Citations]
A New Low Complexity Uniform Filter Bank Based on the Improved Coefficient Decimation Method

In this paper, we propose a new uniform filter bank (FB) based on the improved coefficient decimation method (ICDM). In the proposed FB’s design, the ICDM is used to obtain different multi-band frequency responses using a single lowpass prototype filter. The desired subbands are individually obtained from these multi-band frequency responses by using low order frequency response masking filters and their corresponding ICDM output frequency responses. We show that the proposed FB is a very low complexity alternative to the other FBs in literature, especially the widely used discrete Fourier transform based FB (DFTFB) and the CDM based FB (CDFB). The proposed FB can have a higher number of subbands with twice the center frequency resolution when compared with the CDFB and DFTFB. Design example and implementation results show that our FB achieves 86.59% and 58.84% reductions in resource utilizations and 76.95% and 47.09% reductions in power consumptions when compared with the DFTFB and CDFB respectively.

1. VAIDYANATHAN, P. P. Multirate digital filters, filter banks, polyphase networks, and applications: a tutorial. Proceedings of the IEEE, 1990, vol. 78, no. 1, p. 56-93.
2. MITOLA, J., MAGUIRE, G. Q. Cognitive radio: Making software radios more personal. IEEE Personal Commununications, 1999, vol. 6, no. 4, p. 13–18.
3. HAYKIN, S. Cognitive radio: Brain-empowered wireless communications. IEEE Journal on Selected Areas in Communications, 2005, vol. 23, no. 2, p. 201- 220.
4. FARHANG-BOROUJENY, B. Filter bank spectrum sensing for cognitive radios. IEEE Transactions on Signal Processing, 2008, vol. 56, no. 5, p. 1801-1811.
5. HENTSHEL, T. Channelization for software defined base stations. Annales des Telecommunications, 2002, vol. 57, no. 5-6, p. 386 to 420.
6. MAHESH, R., VINOD, A. P. Coefficient decimation approach for realizing reconfigurable finite impulse response filters. In IEEE International Symposium on Circuits and Systems (ISCAS). Seattle (USA), 18-21 May 2008, p. 81-84.
7. MAHESH, R., VINOD, A. P. Low complexity flexible filter banks for uniform and non-uniform channelisation in software radios using coefficient decimation. IET Circuits, Devices & Systems, 2011, vol. 5, no. 3, p. 232-242.
8. MAHESH, R., VINOD, A. P. A low-complexity flexible spectrumsensing scheme for mobile cognitive radio terminals. IEEE Transactions on Circuits and Systems II: Express Briefs, 2011, vol. 58, no. 6, p. 371-375.
9. AMBEDE, A., SMITHA, K. G., VINOD, A. P. A modified coefficient decimation method to realize low complexity FIR filters with enhanced frequency response flexibility and passband resolution. In Proceedings of the 2012 35th International Conference on Telecommunications and Signal Processing (TSP). Prague (Czech Republic), 3-4 July 2012, p. 658-661.
10. AMBEDE, A., SMITHA, K. G., VINOD, A. P. A low complexity uniform and non-uniform digital filter bank based on an improved coefficient decimation method for multi-standard communication channelizers. Circuits, Systems, and Signal Processing (CSSP), Springer, Published online in December 2012, DOI: 10.1007/s00034-012-9532-9.
11. LIM, Y. C. Frequency-response masking approach for the synthesis of sharp linear phase digital filters. IEEE Transactions on Circuits and Systems, 1986, vol. 33, no. 4, p. 357- 364.
12. SMITHA, K. G., VINOD, A. P. A new low power reconfigurable decimation-interpolation and masking based filter architecture for channel adaptation in cognitive radio handsets. Physical Communication, Elsevier, 2009, vol. 2, no. 1–2, p. 47-57.
13. BELLANGER, M. On computational complexity in digital transmultiplexer filters. IEEE Transactions on Communications, 1982, vol. 30, no. 7, p. 1461- 1465.
14. PROAKIS, J. G., MANOLAKIS, D. G. Digital Signal Processing. 4th ed. Pearson Education, 2007.

Keywords: FIR filter bank, flexibility, improved coefficient decimation method, low complexity

E. Tuğcu, F. Çakır, A. Ozen [references] [full-text] [Download Citations]
A New Step Size Control Technique for Blind and Non-Blind Equalization Algorithms

A new variable step size (VSS) control technique employing cross correlation between channel output and error signal has been proposed as a solution to the problem of slow convergence of blind and non-blind equalization algorithms. The new method resolves the conflict between the convergence rate and low steady state error of the fixed step-size conventional blind and non-blind equalization algorithms, such as Constant Modulus Algorithm (CMA) and Least Mean Squares (LMS) algorithm. Computer simulations have been performed to verify the performance of the proposed method in frequency selective Rayleigh fading channels. The proposed technique has been compared with the popular non-blind equalizers, LMS and Recursive Least Squares (RLS) algorithms, and blind equalizers, the conventional CMA, Zhao’s VSS-CMA and Demir’s VSS-CMA as benchmarks. The obtained simulation results have demonstrated that the proposed VSS-CMA and VSS-LMS algorithms have considerably better performance than the conventional CMA, Zhao’s VSS-CMA and Demir’s VSS-CMA blind equalization algorithms, and the conventional LMS non-blind equalization algorithm.

1. QURESHI, S. U. H. Adaptive equalization. In Proceedings of the IEEE, September 1985, vol. 73, no. 9, p. 1349-1387.
2. BELFIORE, C. A., PARK, J. H. Decision feedback equalization. In Proceedings of the IEEE, August 1979, vol. 67, no. 8, p. 1143 to 1156.
3. BOYD, R. T., MONDS, F. C. Equalizer for digital communication. IEE Electronic Letters, January 1971, vol. 7, no. 2, p. 58-60.
4. HAYKIN, S. Communication Systems. Third edition. John Wiley and Sons, 1994.
5. PROAKIS, J. G. Digital Communications. Fourth edition. Singapore: McGraw-Hill Co., 2001.
6. GODARD, D. N. Self-recovering equalization and carrier tracking in two dimensional data communication systems. IEEE Transactions on Communications, 1980, vol. 28, no. 11, p.1867-1875.
7. SHALVI, O., WEINSTEIN, E. New criteria for blind deconvolution of non-minimum phase systems (channels). IEEE Transactions on. Information Theory, March 1990, vol. 36, no. 2, p. 312-321.
8. LABAT, J., MACCHI, O., LAOT, C. Adaptive decision feedback equalization: Can you skip the training period? IEEE Transactions on Communications, July 1998, pp. 921-930.
9. KIM, Y. H., SHAMSUNDER, S. Adaptive algorithms for channel equalization with soft decision feedback. IEEE Journal on Selected Areas in Communications, December 1998, p. 1660-1669.
10. ANANTHASWAMY, G., GOECKEL, D. L. A fast acquiring blind predictive DFE. IEEE Transactions on Communications, October 2002, vol. 50, no. 10, p. 1557-1560.
11. SATO, Y. A method of self-recovering equalization for multilevel amplitude modulation. IEEE Transactions on Communications, June 1975, vol. COM-23, p. 679-682.
12. WIDROW, B. Adaptive filters I: Fundamentals. Stanford Electronic Laboratories Technical Report 6764-6, December 1966.
13. XIONG, Z., LINSHENG, L., DONFENG, Z., ZENGSHOU, D. A new adaptive step-size blind equalization algorithm based on autocorrelation of error signal. In 7th International Conference on Signal Processing, 2004, vol. 2, p. 1719-1722.
14. LIYI, Z., LEI, C., YUNSHAN, S. Variable step-size CMA blind equalization based on non-linear function of error signal. In International Conference on Communications and Mobile Computing, 2009, vol. 1, p. 396-399.
15. SHAHZAD, K., ASHRAF, M., IQBAL, R. Improved blind equalization scheme using variable step size constant modulus algorithm. In Proceedings of the 7th WSEAS Int. Conf. on Signal Processing, Computational Geometry & Artificial Vision. August 2007, p. 86-90.
16. BAOFENG, Z., JUMIN, Z., DENGAO, L. A new variable stepsize constant modulus blind equalization algorithm. In IEEE International Conference on Artificial Intelligence and Computational Intelligence, 2010, p. 289-291.
17. ZHIMIN, D., SHENG, Z., PENG, W., WEILING, W. Novel variable step size constant modulus algorithms for blind multiuser detection. In 54th IEEE Conference on VTS Vehicular Technology Conference, 7-11 October 2001, vol. 2, p. 673–677.
18. OZEN, A., KAYA, I., SOYSAL B. Variable step-size constant modulus algorithm employing fuzzy logic controller. Wireless Personal Communications, July 2010, vol. 54, no. 2, p. 237-250.
19. ZIPF, J. G. F., TOBIAS, O. J., SEARA R. A VSSLMS algorithm based on error autocorrelation. In 16th European Signal Processing Conference (EUSIPCO 2008). Lausanne (Switzerland), August 2008, p. 25-29.
20. OZEN, A. A novel variable step size adjustment method based on channel output autocorrelation for the LMS training algorithm. International Journal of Communication Systems (Wiley-Blackwell), 2011, vol. 24, no. 7, p. 938-949.
21. DEMİR, M. A., OZEN, A. A novel variable step size adjustment method based on autocorrelation of error signal for the constant modulus blind equalization algorithm. Radioengineering, April 2012, vol. 21, no. 1, p. 37-45.
22. ABOULNASR, T., MAYYAS, K. A robust variable step size LMS type algorithm: Analysis and simulations. IEEE Transactions on Signal Processing, March 1997, vol. 45, no. 3, p. 631-639.
23. KWONG, R. H., JOHNSTON, E. W. A variable step size LMS algorithm. IEEE Transactions on Signal Processing, July 1992, vol. 40, no. 7, p. 1633-1642.
24. TREICHLER, J. R., AGEE, B. G. A new approach to multipath correction of constant modulus signals. IEEE Trans. Acoustic Speech, Signal Processing, 1983, vol. ASSP-28, p. 459-472.
25. HAYES, M. H. Statistical Digital Signal Processing and Modeling. New York: John Wiley & Sons, Inc., 1996.

Keywords: Cross correlation, VSS-CMA, VSS-LMS, blind equalization, adaptive blind and non-blind training.

J. Pribil, A. Pribilova [references] [full-text] [Download Citations]
Determination of Formant Features in Czech and Slovak for GMM Emotional Speech Classifier

The paper is aimed at determination of formant features (FF) which describe vocal tract characteristics. It comprises analysis of the first three formant positions together with their bandwidths and the formant tilts. Subsequently, the statistical evaluation and comparison of the FF was performed. This experiment was realized with the speech material in the form of sentences of male and female speakers expressing four emotional states (joy, sadness, anger, and a neutral state) in Czech and Slovak languages. The statistical distribution of the analyzed formant frequencies and formant tilts shows good differentiation between neutral and emotional styles for both voices. Contrary to it, the values of the formant 3-dB bandwidths have no correlation with the type of the speaking style or the type of the voice. These spectral parameters together with the values of the other speech characteristics were used in the feature vector for Gaussian mixture models (GMM) emotional speech style classifier that is currently developed. The overall mean classification error rate achieves about 18 %, and the best obtained error rate is 5 % for the sadness style of the female voice. These values are acceptable in this first stage of development of the GMM classifier that should be used for evaluation of the synthetic speech quality after applied voice conversion and emotional speech style transformation.

1. CHETOUANI, M., MAHDHAOUI, A., RINGEVAL, F. Timescale feature extractions for emotional speech characterization. Cognitive Computation, 2009, vol. 1, p. 194-201.
2. LUENGO, I., NAVAS, E., HERNAEZ, I. Feature analysis and evaluation for automatic emotion identification in speech. IEEE Transactions on Multimedia, 2010, vol. 12, p. 490-501.
3. SCHERER, K. R. Vocal communication of emotion: A review of research paradigms. Speech Communication 2003, vol. 40, p. 227 to 256.
4. HE, L., LECH, M., MADDAGE, N. C, ALLEN, N. B. Study of empirical mode decomposition and spectral analysis for stress and emotion classification in natural speech. Biomedical Signal Processing and Control, 2011, vol. 6, p. 139-146.
5. CHALOUPKA, Z., UHLIR, J. Speech defect analysis using hidden Markov models. Radioengineering, April 2007, vol. 16, no. 1, p. 67-72.
6. BOZKURT, E., ERZIN, E., ERDEM, Ç. E., ERDEM, A. T. Formant position based weighted spectral features for emotion recognition. Speech Communication, 2011, vol. 53, p. 1186-1197.
7. YUN, S., YOO, C. D. Loss-scaled large-margin Gaussian mixture models for speech emotion classification. IEEE Transactions on Audio, Speech, and Language Processing, 2012, vol. 20, no. 2, p. 585-598.
8. KOOLAGUDI, S. G., KROTHAPALLI, R. S. Two stage emotion recognition based on speaking rate. International Journal of Speech Technology, 2011, vol. 14, p. 35-48.
9. ATASSI, H., RIVIELLO, M. T., SMEKAL, Z., HUSSAIN, A., ESPOSITO, A. Emotional vocal expressions recognition using the COST 2102 Italian database of emotional speech. In Esposito, A. et al. (eds.) Development of Multimodal Interfaces: Active Listening and Synchrony, LNCS 5967, Springer-Verlag Berlin Heidelberg, 2010, p. 255-267.
10. RENCHER, A. C., SCHAALJE, G. B. Linear Models in Statistics. Second edition. John Wiley & Sons, 2008.
11. MIZUSHIMA, T. Multisample tests for scale based on kernel density estimation. Statistics & Probability Letters, 2000, vol. 49, p. 81-91.
12. STOICA, P., MOSES, R. L. Introduction to Spectral Analysis. Prentice-Hall, 1997, p. 52-54.
13. VICH, R., PRIBIL, J., SMEKAL, Z. New cepstral zero-pole vocal tract models for TTS synthesis. In Proceedings of the IEEE Region 8 EUROCON'2001, Vol. 2, Section S22-Speech Compression and DSP. Bratislava (Slovakia), 2001, p. 458-462.
14. FANT, G. Acoustical analysis of speech. In Crocker, M.J. (ed.) Encyclopedia of Acoustics. John Wiley & Sons, 1997, p. 1589 to 1598.
15. FANT, G. Speech Acoustics and Phonetics. Dordrecht: Kluwer Academic Publishers, 2004.
16. ILK, H. G., EROĞUL, O., SATAR, B., OZKAPTAN, Y. Effects of tonsillectomy on speech spectrum. Journal of Voice, 2002, vol. 16, p. 580-586.
17. BOERSMA, P., WEENINK, D. Praat: Doing Phonetics by Computer (Computer Program, Version 5.2.20). [Online] Cited 2011-03-25. Available at: http://www.praat.org/
18. REYNOLDS, D. A., ROSE, R. C. Robust text-independent speaker identification using Gaussian mixture speaker models. IEEE Transactions on Speech and Audio Processing, 1995, vol. 3, p. 72-83.
19. BURGET, R., KARASEK, J., SMEKAL, Z. Recognition of emotions in Czech newspaper headlines. Radioengineering, April 2011, vol. 20, no. 1, p. 39-47.
20. NABNEY, I. T. Netlab Pattern Analysis Toolbox. Copyright (1996-2001). Retrieved 16 February 2012, from http://www.mathworks.com/matlabcentral/fileexchange/2654- netlab
21. LEE, C. M. Toward detecting emotions in spoken dialogs. IEEE Transactions on Speech and Audio Processing, March 2005, vol. 13, no. 2, p. 293-303.
22. HANZLICEK, Z., MATOUSEK, J., TIHELKA, D. First experiments on text-to-speech system personification. In Text, Speech and Dialogue, LNCS vol. 5729, Springer-Verlag Berlin Heidelberg, 2009, p. 186-193.
23. GRUBER, M., HANZLICEK, Z. Czech expressive speech synthesis in limited domain comparison of unit selection and HMM-based approaches. In P. Sojka et al. (Eds.) TSD 2012, LNCS vol. 7499, Springer-Verlag Berlin Heidelberg, 2012, p. 656–664.
24. BURKHARDT, F., PAESCHKE, A., ROLFES, M., SENDLMEIER, W., WEISS, B. A. Database of German emotional speech. In Proceedings of INTERSPEECH 2005. ISCA, Lisbon (Portugal), 2005, p.1517-1520.

Keywords: Formant features of speech, emotional speech, statistical analysis

R.Rui, C.C.Bao [references] [full-text] [Download Citations]
Musical Instrument Classification Based on Nonlinear Recurrence Analysis and Supervised Learning

In this paper, the phase space reconstruction of time series produced by different instruments is discussed based on the nonlinear dynamic theory. The dense ratio, a novel quantitative recurrence parameter, is proposed to describe the difference of wind instruments, stringed instruments and keyboard instruments in the phase space by analyzing the recursive property of every instrument. Furthermore, a novel supervised learning algorithm for automatic classification of individual musical instrument signals is addressed deriving from the idea of supervised non-negative matrix factorization (NMF) algorithm. In our approach, the orthogonal basis matrix could be obtained without updating the matrix iteratively, which NMF is unable to do. The experimental results indicate that the accuracy of the proposed method is improved by 3% comparing with the conventional features in the individual instrument classification.

1. EVERY, M. R. Discriminating between pitched sources in music audio. IEEE Transactions on Audio, Speech, and Language Processing, 2008, vol. 16, no. 2, p. 267 - 277.
2. ZLATINTSI, A., MARAGOS, P. AM-FM modulation features for music instrument signal analysis and recognition. In Proc. 20th European Signal Processing Conference. 2012, p. 2035 - 2039.
3. ERONEN, A. Comparison of features for musical instrument recognition. In Proc. IEEE Workshop Appl. Signal Process. Audio Acoust. 2001, p. 19 - 22.
4. KOSTEK, B. Musical instrument classification and duet analysis employing music information retrieval techniques. Proc. of IEEE, 2004, vol. 92, no. 4, p. 712 - 729.
5. BENETOS, E., KOTTI, M., KOTROPOULOS, C. Musical instrument classification using non-negative matrix factorization algorithms and subset feature selection. In Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing ICASSP. 2006, p. V221 - V224.
6. BENETOS, E., KOTTI, M., KOTROPOULOS, C. Large scale musical instrument identification. In Proc. of 4th Sound and Music Computing Conf. 2007, p. 283 - 286.
7. BARBEDO, J. G. A., TZANETAKI, G. Musical instrument classification using individual partials. IEEE Transactions on Audio, Speech, and Language Processing, 2011, vol. 19, no. 1, p. 111 - 122.
8. SHA, Y.-T., BAO, CH., JIA, M.-S., LIU, X. High frequency reconstruction of audio signal based on chaotic prediction theory. In Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP. 2010, p. 381 - 384.
9. SERRÀ, J., DE LOS SANTOS, C. A., ANDRZEJAK, R. G. Nonlinear audio recurrence analysis with application to genre classification. In Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP. 2011, p. 169 - 172.
10. TAKENS, F. Detecting strange attractors in turbulence. Lecture Notes in Math., 1981, vol. 898, p. 366 - 381.
11. KANTZ, H., SCHREIBER, T. Nonlinear Time Series Analysis. 2nd edition. Cambridge (UK): Cambridge University Press, 2004.
12. KITAHARA, T., GOTO, M., KOMATANI, K., OGATA, T., OKUNO, H. G. Musical instrument recognizer instrogram and its application to music retrieval based on instrumentation similarity. In Proc. IEEE International Symposium on Multimedia. 2006, p. 265 - 272.
13. ECKMANN, J.-P., OLIFFSON KAMPHORST, S., RUELLE, D. Recurrence plots of dynamical systems. Europhys. Lett., 1987, vol. 4, p. 973 - 977.
14. ZBILUT, J. P., WEBBER JR., C. L. Embeddings and delays as derived from quantification of recurrence plots. Phys. Lett. A, 1992, vol. 171, p. 199 - 203.
15. ZHANG, L., BAO, CH., LIU, X., ZHANG, X., BAO, F., BU, B. Audio classification algorithm based on nonlinear characteristics analysis. In Proc. Asia Pacific Signal and Information Processing Association Annual Summit and Conference. 2011, p. 214 - 217.
16. LEE, D. D., SEUNG, H. S. Algorithm for non-negative matrix factorization. Advances in Neural Information Processing Systems, 2001, vol. 13, p. 556 - 562.
17. VAN DER HEIJDEN, F., DUIN, R. P. W., DE RIDDER, D., TAX, D. M. J. Classification, Parameter Estimation and State Estimation: An Engineering Approach Using MATLAB. London (UK): Wiley, 2004.

Keywords: Phase space reconstruction, recurrence analysis, dense ratio, supervised learning, musical instrument classification

M. Zukal, J. Mekyska, P. Cika, Z. Smekal [references] [full-text] [Download Citations]
Interest Points as a Focus Measure in Multi-Spectral Imaging

A novel multi-spectral focus measure that is based on algorithms for interest point detection, particularly on the FAST (Features from Accelerated Segment Test), Fast Hessian and Harris-Laplace detector, is described in this paper. The proposed measure methods are compared with commonly used focus measure techniques like energy of image gradient, sum-modified Laplacian, Tenenbaum's algorithm or spatial frequency when testing their reliability and performance. The measures have been tested on a newly created database containing 420 images acquired in visible, near-infrared and thermal spectrum (7 objects in each spectrum). Algorithms based on the interest point detectors proved to be good focus measures satisfying all the requirements described in the paper, especially in thermal spectrum. It is shown that these algorithms outperformed all commonly used methods in thermal spectrum and therefore can serve as a new and more accurate focus measure.

1. HUANG, W., JING, Z. Evaluation of focus measures in multi-focus image fusion. Pattern Recognition Letters, 2007, vol. 28, no. 4, p. 493 - 500.
2. ESPINOSA-DURO, V., FAUNDEZ-ZANUY, M., MEKYSKA, J. Beyond cognitive signals. Cognitive Computation, 2011, vol. 3, no. 2, p. 374 - 381.
3. ESPINOSA-DURO, V., FAUNDEZ-ZANUY, M., MEKYSKA, J., MONTE-MORENO, E. A criterion for analysis of different sensor combinations with an application to face biometrics. Cognitive Computation, 2010, vol. 2, no. 3, p. 135 - 141.
4. ESPINOSA-DURO, V., FAUNDEZ-ZANUY, M., MEKYSKA, J. A new face database simultaneously acquired in visible, nearinfrared and thermal spectrums. Cognitive Computation, 2012, vol. 5, no. 1, p. 1 - 17.
5. FAUNDEZ-ZANUY, M., MEKYSKA, J., ESPINOSA-DURO´ , V. On the focusing of thermal images. Pattern Recognition Letters, 2011, vol. 32, no. 11, p. 1548 - 1557.
6. BENES, R., DVORAK, P., FAUNDEZ-ZANUY, M., ESPINOSADURO, V., MEKYSKA, J. Multi-focus thermal image fusion. Pattern Recognition Letters, 2012, vol. 34, no. 5, p. 536 - 544.
7. ZUKAL, M., CIKA, P., BURGET, R. Evaluation of interest point detectors for scenes with changing lightening conditions. In Proceedings of the 34th International Conference on Telecommunications and Signal Processing (TSP). Budapest (Hungary), 2011, p. 579 - 583.
8. KROTKOV, E. Focusing. International Journal of Computer Vision, 1987, vol. 1, p. 223 - 237.
9. SUBBARAO, M., CHOI, T., NIKZAD, A. Focusing techniques. Optical Engineering, 1993, vol. 32, no. 11, p. 2824 - 2836.
10. RUSS, J. C. Image Processing Handbook,, 4th ed. Boca Raton (FL, USA): CRC Press, 2006.
11. NAYAR, S., NAKAGAWA, Y. Shape from focus. IEEE Transactions on Pattern Analysis and Machine Intelligence, 1994, vol. 16, no. 8, p. 824 - 831.
12. ESKICIOGLU, A., FISHER, P. Image quality measures and their performance. IEEE Transactions on Communications, 1995, vol. 43, no. 12, p. 2959 - 2965.
13. TUYTELAARS, T., MIKOLAJCZYK, K. Local Invariant Feature Detectors: A Survey. Hanover (MA, USA): Now Publishers, 2008.
14. ROSTEN, E., PORTER, R., DRUMMOND, T. Faster and better: A machine learning approach to corner detection. IEEE Transactions on Pattern Analysis and Machine Intelligence, 2010, vol. 32, no. 1, p. 105 - 119.
15. BAY, H., TUYTELAARS, T., GOOL, L. V. Surf: Speeded up robust features. In Proceedings of the 9th European Conference on Computer Vision. Graz (Austria), 2006, p. 404 - 417.
16. VIOLA, P., JONES, M. Robust real-time object detection. International Journal of Computer Vision, 2001.
17. MIKOLAJCZYK, K., SCHMID, C. Scale & affine invariant interest point detectors. International Journal of Computer Vision, 2004, vol. 60, p. 63 - 86.
18. HARRIS, C., STEPHENS, M. A combined corner and edge detection. In Proceedings of the 4th Alvey Vision Conference. Manchester (United Kingdom), 1988, p. 147 - 151.
19. FLIR, United States. FLIR SC660, The High Performance infrared inspection system (datasheet). 2 pages. [Online] Cited 2013-03-04. Available at: http://webs.uvigo.es/ramiro/sc660datasheet.pdf.
20. MEKYSKA, J., ZUKAL, M., CIKA, P., SMEKAL, Z. Interest points as a focus measure. In Proceedings of the 35th International Conference on Telecommunications and Signal Processing (TSP) Prague (Czech Republic), 2012, p. 774 - 778.
21. JANE, O., GOKHAN, H. A quantitative study on optimum parameters selection in adaptive unsharp masking technique for infrared images. Radioengineering, 2009, vol. 18, no. 4, p. 611 - 617.
22. LOWE, D. G. Distinctive image features from scale-invariant keypoints. International Journal of Computer Vision, 2004, vol. 60, no. 2, p. 91 - 110.

Keywords: Focus measure, interest points detector, multi-spectral imaging, gradient, Fast Hessian, Harris-Laplace detector

L. Bolecek, V. Ricny, M. Slanina [references] [full-text] [Download Citations]
3D Reconstruction: Novel Method for Finding of Corresponding Points using Pseudo Colors

This paper deals with the reconstruction of spatial coordinates of an arbitrary point in a scene using two images scanned by a 3D camera or two displaced cameras. Calculations are based on the perspective geom-etry. Accurate determination of corresponding points is a fundamental step in this process. The usually used methods can have a problem with points, which lie in areas without sufficient contrast. This paper describes our proposed method based on the use of the relationship between the selected points and area feature points. The proposed method finds correspondence using a set of feature points found by SURF. An algorithm is proposed and described for quick removal of false correspondences, which could ruin the correct reconstruction. The new method, which makes use of pseudo color image representation (pseudo coloring) has been proposed subsequently. By means of this method it is possible to significantly increase the color contrast of the surveyed image, and therefore add more information to find the correct correspondence. Reliability of the found correspondence can be verified by reconstruction of 3D position of selected points. Executed experiments confirm our assumptions

1. LIANG, Y., TAM, W. J. Stereoscopic image generation based on depth images for 3D TV. IEEE Transactions on Broadcasting, 2005, vol.51, no.2, p. 191 – 199.
2. KAMENCAY, P., BREZNAN, M., JARINA, R., LUKAC, P. Depth map computation using hybrid segmentation algorithm. In 34th International Conference on Telecommunications and Signal Processing (TSP). Budapest (Hungary), 2011, p. 584 - 588.
3. GRUEN, A., HUANG, T. S. (Eds.) Calibration and Orientation of Cameras in Computer Vision. Berlin (Germany): Springer, 2001.
4. ZHANG, Z. Flexible camera calibration by viewing a plane from unknown orientations. In The Proceedings of the Seventh IEEE International Conference on Computer Vision. Kerkyra (Greece), 1999, p. 666 - 673.
5. MENDONCA, P. R. S., CIPOLLA, R. A simple technique for selfcalibration. In IEEE Computer Society Conference on Computer Vision and Pattern Recognition. Ft. Collins (CO, USA), 1999.
6. TUYTELAARS, T., MIKOLAJCZYK, K. Local invariant feature detectors: a survey. Foundations and Trends in Computer Graphics and Vision, 2008, vol. 3, no. 3, p. 177 - 280.
7. STEFFEN, G., HOLLERER, T., TURK, M. Evaluation of interest point detectors and feature descriptors for visual tracking. International Journal of Computer Vision, 2011, vol. 94, no. 3, p. 335 - 360.
8. KALIA, R., KEUN-DONG, L. SAMIR, B. V. R., SUNG-KWAN, J., WEON-GEUN, O. An analysis of the effect of different image preprocessing techniques on the performance of SURF: Speeded up robust features. In 17th Korea-Japan Joint Workshop on Frontiers of Computer Vision (FCV). Ulsan (Korea), 2011.
9. BAY, H., TUYTELAARS, T., GOOL, L. V. SURF: Speeded up robust features. In Proceedings of the 9th European Conference on Computer Vision. Graz (Austria), 2006, p. 404 - 417.
10. CHUAN, L., JINJIN, Z., CHUANGYIN, D., HONGJUN, Z. A. Method of 3D reconstruction from image sequence. In 2nd International Congress on Image and Signal Processing (CISP). Tianjin (China), 2009., p. 1 - 5.
11. FISCHER, M. A., BOLLES, R. C. Random sample consensus: A paradigm for model fitting with applications to image analysis and automated cartography. Communication of the ACM, 1981, vol. 24, no. 6, p. 381 - 395.
12. LOWE, D. Distinctive image features from scale-invariant keypoints. International Journal of Computer Vision, 2004, vol. 60, no. 2, p. 91 - 110.
13. BOUGUET, J.-Y. Camera Calibration Toolbox for Matlab, open source software. [Online] Cited 2010-07-09. Available at: http://www.vision.caltech.edu/bouguetj/calib_doc/.
14. MIKHAIL, E. M., BETHEL J. S., MCGLONE, J. CH. Introduction to Modern Photogrammetry. New York: Wiley, 2001.
15. KRAUS, K. Photogrammetry: Geometry from Images and Laser Scans, 2nd ed. Berlin: Walter de Gruyter, 2007.
16. MA, Y., SOATTO, S., KOSECKA, J., SASTRY, S. S. An Invitation to 3-D Vision: From Images to Geometric Models. New York: Springer, 2004.
17. KROON, D.-J. OpenSURF, open source software. [Online] Cited 2010-09-06. Available at: http://www.mathworks.com/ matlabcentral/fileexchange/28300-opensurf-including-image-warp
18. STANCIK, P. Optoelectronic and Photogrammetric Measurement Systems, Ph.D. thesis. Brno (Czech Republic): Brno University of Technology, 2008. In Czech.
19. YOUVAN, D. Pseudocolor in Pure and Applied Mathematics: A Free on-Line e-Book with Source Code. [Online] Cited 2011-04- 18. Available at: http://www.youvan.com/ .
20. LU, X-J., DING, M-X., WANG, Y-K. A New Pseudocolor Transform for Fibre Masses Inspection of Industrial Images. [Online] Cited 2011-4-11. Available at: http://www.aas.net.cn/ qikan/manage/wenzhang/2007-1284.pdf .
21. LEHMAN, T., KASER, A., REPGES, R. A Simple Parametric Equation for Pseudocoloring Grey Scale Images Keeping Their Original Brightness Progression. [Online]. Cited 20011-4-11. Available at: http://ganymed.imib .
22. BOLECEK, L. Displaying Grayscale Images in False Colors, diploma thesis. Brno (Czech Republic): Brno University of Technology, 2009.
23. BOLECEK, L., RICNY, V., SLANINA, M. Fast method for reconstruction of 3D coordinates. In 35th International Conference on Telecommunications and Signal Processing. Prague(Czech Republic), 2012, p. 740 - 744.
24. FANG-HSUAN, C., TZU-HAO, K., YEA-SHUAN, H. Fast depth estimation method from a pair of retified images. In Eighth International Conference on Intelligent Information Hiding and Multimedia Signal Processing (IIH-MSP). Piraeus-Athens (Greece), 2012, p. 375 - 378.
25. MOALLEM, P., FAEZ, K. Search space reduction in the edge based stereo matching by context of disparity gradient limit. In Proceedings of the 2nd International Symposium on Image and Signal Processing and Analysis (ISPA). Pula (Croatia), 2001, p. 164 - 169.
26. FOURIE, J., GREEN, R., MILLS, S. Directed correspondence search: Finding feature correspondences in images using the Harmony Search algorithm. In 24th International Conference Image and Vision Computing (IVCNZ). Wellington (New Zealand), 2009, p. 102 - 107.
27. GONG-JIAN, W., JIN-JIAN, L., WEN-XIAN, Y. A highperformance feature-matching method for image registration by combining spatial and similarity information. IEEE Transactions on Geoscience and Remote Sensing, 2008, vol. 46, no. 4, p. 1266 - 1277.
28. MACIEL, J., COSTEIRA, J. P. A global solution to sparse correspondence problems. IEEE Transactions on Pattern Analysis and Machine Intelligence, 2003, vol. 25, no. 2, p. 187 - 199.

Keywords: 3D reconstruction, features points, image correspondence, pseudo color.

P. Kamencay, M. Zachariasova, R. Hudec, R. Jarina, M. Benco, J. Hlubik [references] [full-text] [Download Citations]
A Novel Approach to Face Recognition using Image Segmentation based on SPCA-KNN Method

In this paper we propose a novel method for face recognition using hybrid SPCA-KNN (SIFT-PCA-KNN) approach. The proposed method consists of three parts. The first part is based on preprocessing face images using Graph Based algorithm and SIFT (Scale Invariant Feature Transform) descriptor. Graph Based topology is used for matching two face images. In the second part eigen values and eigen vectors are extracted from each input face images. The goal is to extract the important information from the face data, to represent it as a set of new orthogonal variables called principal components. In the final part a nearest neighbor classifier is designed for classifying the face images based on the SPCA-KNN algorithm. The algorithm has been tested on 100 different subjects (15 images for each class). The experimental result shows that the proposed method has a positive effect on overall face recognition performance and outperforms other examined methods.

1. BELHUNMEUR, P. N., HESPANHA, J. P., KRIEGMAN, D. J. Eigenfaces vs. fisherfaces recognition using class specific linear projection. IEEE Trans Pattern Analysis and Machine Intelligence, 1997.
2. ZHAO, W., CHELLAPPA, R., ROSENFELD, A. Face recognition: a literature survey. ACM Computing Surveys, 2003, vol. 35, no. 4, p. 399-458.
3. BERND, H., KOSHIZEN, T. Components for face recognition. In Proceedings of the 6th International Conference on Automatic Face and Gesture Recognition. Seoul (Korea), 2004, p. 153 - 158.
4. MARCIALS, G. L., ROLI, F. Fusion of LDA and PCA for face recognition. In Proc. of the Workshop on Machine Vision and Perception. 8th Meeting of the Italian Association of Artificial Intelligence. Siena (Italy), 2002.
5. JIANBO, S., MALIK, J. Normalized cuts and image segmentation. IEEE Transactions on Pattern Analysis and Machine Intelligence, 2002, vol. 22, no. 8, p. 888 - 905.
6. HE, R., ZHU, Y. A hybrid image segmentation approach based on Mean Shift and fuzzy C – means. In Asia – Pacific Conference on Information Processing. [Online] 2009.
7. YANG, W., LEI, Z., SANG, J. 2D-3D face matching using CCA method. National Laboratory of Pattern Recognition Institute of Automation. Beijing (China), 2008.
8. CORTES, C., VAPNIK, V. Support vector networks. Machine Learning, 1995, vol. 20, p. 273-297.
9. PARVEEN, P., THURAISINGHAM, B. Face recognition using multiple classifiers. In 18th IEEE International Conference on Tools with Artificial Intelligence (ICTAI). 2006, p. 179-186.
10. KWAK, K. C., PEDRYEZ, W. Face recognition: A study in information fusion using fuzzy integral. Pattern Recognition Letters, 2005, vol. 26, p. 719 - 733.
11. FELENZWALB, P. F., KLETTE, R. Efficient graph-based image segmentation. International Journal of Computer Vision, 2004, vol. 59, no. 2. [Online]
12. DONG, L., OGUNBONA, P., LI, W., YU, G., FAN, L., ZHENG, G. A fast algorithm for color image segmentation. In First International Conference on Innovative Computing. Information and Control (ICICIC), 2006. [Online]
13. LOWE, D. G. Distinctive image features from scale-invariant keypoints. International Journal of Computer Vision, 2004, vol. 60, no. 2, p. 91-110.
14. MIKOLAJCZYK, K., SCHMID, D. Scale and affine invariant interest point detectors. International Journal of Computer Vision, 2008, vol. 60, no. 1, p. 63-86.
15. BOLECEK, L., RICNY, V. SLANINA, M. Fast method for reconstruction of 3D coordinates. In 35th International Conference on Telecommunications and Signal Processing (TSP), 2012, ISBN 978-1-4673-1115-1.
16. COOLEY, W., LOHNES, W. PCA correlation. P. R. Multivariate Data Analysis. New York:John Wiley & Son. Inc.
17. HE, Y., ZHAO, L., ZOU, C., LIPO, W., KE, C., SOON, O. Y. Face recognition based on PCA/KPCA plus CCA. In Proceedings of International Conference on Advances in Natural Computation. Heidelberg: Springer. LNCS 3611. 2005, p. 71-74.
18. MURALIDHARAN, R., CHANDRASEKAR, C. Combining local and global feature for object recognition using SVM-KNN. In Proceedings of International Conference on Pattern Recognition. Informatics and Medical Engineering. 2012, ISBN 978-1-4673- 1039-0/12.
19. MAZANEC, J., MELISEK, M., ORAVEC, M., PAVLOVICOVA, J. Support Vector M achine, PCA and LDA in face recognition. Journal of Electrical Engineering, 2008, vol. 59, no. 4, p. 203 to 209.
20. MA, Y., DING, X. Face detection based on hierarchical Support Vector Machines. Proc. ICRP, 2002, p. 222-225.
21. MARTINEZ, A. M., KAK, A. C. PCA versus LDA. IEEE Trans. Pattern Analysis and Machine Intelligence, 2001, vol. 23, no. 2, p. 228-233.
22. TURK, M., PENTLAND, A. Eigenfaces for recognition. Journal of Cognitive Neuroscience, 1991, vol. 3, no. 1, p. 71 - 86.
23. JUAN, L., GWUN, O. A comparison of SIFT, PCA-SIFT and SURF. International Journal of Image Processing, 2009, vol. 3, no. 4, p. 143-152.
24. YAN, K., SUKTHANKAR, R. PCA-SIFT: A more distinctive representation for local image descriptors. In Proc. IEEE Conf. Computer Vision and Pattern Recognition (CVPR). 2004, vol. 2, p. 506-513.
25. LI, L., ZHANG, Y., ZHAO, Y. K-nearest neighbors for automated classification of celestial objects. Science in China Series G-Phys Mech Astron., 2008, vol. 51, no. 7, p. 916 - 922.
26. KIRBY, M., SIROVICH, L. Application of the Karhunen-Loeve procedure for the characterization of human faces. IEEE Trans. Pattern Anal. Mach. Intelligence, 1990, vol. 12, no.1, p. 103 - 107.
27. CHENNAMMA, H. R., RANGARAJAN, L., RAO, M. S. Robust near-duplicate image matching for digital image forensics. International Journal of Digital Crime and Forensics, 2009, vol. 1, no. 3, 18 p.
28. ZHOU, Y., MAYYAS, A., MOHAMMED, A. PCA based image fusion routine with application to automotive stamping split detection. Research in Nondestructive Evaluation, 2011, p. 76 - 91.
29. Essex Face Database. [Online] Cited 2012-01-17. Available at: http://cswww.essex.ac.uk/mv/allfaces/index.html.
30. CONDONE, C., RUIZ, A., CABELLO, E. PCA vs. Low Resolution Images in face verification. In Proceedings of the 12th International Conference on Image Analysis and Processing, 2003.
31. BACH, F. R., JORDAN, M. I. A probabilistic interpretation of canonical correlation analysis. TR 688. University of California, Berkley, 2005.

Keywords: Image segmentation, face recognition, PCA, KNN, SPCA-KNN, ESSEX face database.

M. Danciu, M. Gordan, C. Florea, R. Orghidan, E. Sorantin, A. Vlaicu [references] [full-text] [Download Citations]
A Hybrid 3D Learning-and-Interaction-based Segmentation Approach Applied on CT Liver Volumes

Medical volume segmentation in various imaging modalities using real 3D approaches (in contrast to slice-by-slice segmentation) represents an actual trend. The increase in the acquisition resolution leads to large amount of data, requiring solutions to reduce the dimensionality of the segmentation problem. In this context, the real-time interaction with the large medical data volume represents another milestone. This paper addresses the twofold problem of the 3D segmentation applied to large data sets and also describes an intuitive neuro-fuzzy trained interaction method. We present a new hybrid semi-supervised 3D segmentation, for liver volumes obtained from computer tomography scans. This is a challenging medical volume segmentation task, due to the acquisition and inter-patient variability of the liver parenchyma. The proposed solution combines a learning-based segmentation stage (employing 3D discrete cosine transform and a probabilistic support vector machine classifier) with a post-processing stage (automatic and manual segmentation refinement). Optionally, an optimization of the segmentation can be achieved by level sets, using as initialization the segmentation provided by the learning-based solution. The supervised segmentation is applied on elementary cubes in which the CT volume is decomposed by tilling, thus ensuring a significant reduction of the data to be classified by the support vector machine into liver/not liver. On real volumes, the proposed approach provides good segmentation accuracy, with a significant reduction in the computational complexity.

1. LEE, J., KIM, N., LEE, H., SEO, J. B., WON, H. J. Y., SHIN, M. Efficient liver segmentation using a level-set method with optimal detection of the initial liver boundary from level-set speed images. Computer Methods and Programs in Biomedicine, 2007, vol. 88, p. 26–38.
2. SADDI, K. A., ROUSSON, M., CHEFD’HOTEL, C., CHERIET, F. Global-to-local shape matching for liver segmentation in CT imaging. In HEIMANN, T., STYNER, M., VAN GINNEKEN, B. (Eds.): 3D Segmentation in the Clinic: A Grand Challenge, 2007, p. 207–214.
3. WIMMER, A., SOZA, G., HORNEGGER, J. Two-stage semiautomatic organ segmentation framework using radial basis functions and level sets. In 3D Segmentation in the Clinic: A Grand Challenge, MICCAI Workshop. Springer; 2007, p. 179–188.
4. BEICHEL, R., BAUER, C., BORNIK, A., SORANTIN, E. Liver segmentation in CT data: A segmentation refinement approach. In Proc. MICCAI Workshop 3-D Segmentat. Clinic: A Grand Challenge, 2007, p. 235.
5. BECK, A., AURICH, V. HepaTux – A semiautomatic liver segmentation system. In HEIMANN, T., STYNER, M., VAN GINNEKEN, B. (Eds.): 3D Segmentation in the Clinic: A Grand Challenge, 2007, p. 225–233.
6. ZHENG, Y., YANG, X., YE, X. Fully automatic segmentation of liver from multiphase liver CT. San Diego (USA), Proc. SPIE 6512, 2007.
7. SEO, K. S., KIM, H. B., PARK, T., KIM, P. K., PARK, J. A. Automatic liver segmentation of contrast enhanced CT images based on histogram processing. In First International Conference Advances in Natural Computation ICNC 2005. Changsha (China), p. 1027-1030.
8. RATHORE, S., IFTIKHAR, M. A, HUSSAIN, M., JALIL, A. Texture analysis for liver segmentation and classification: A survey. In Frontiers of Information Technology (FIT), Dec.19-21, 2011, p.121-126,
9. CAMPADELLI, P., CASIRAGHI, E., LOMBARDI, G. Automatic liver segmentation from abdominal CT scans. In Proceedings of the 14th International Conference on Image Analysis and Processing, 2007, p. 731-736.
10. FURUKAWA, D., SHIMIZU, A., KOBATAKE, H. Automatic liver segmentation based on maximum a posterior probability estimation and level set method. In Proc. MICCAI Workshop on 3-D Segmentat. Clinic: A Grand Challenge, 2007.
11. RIKXOORT, E., ARZHAEVA, Y., GINNEKEN, B. Automatic segmentation of the liver in computed tomography scans with voxel classification and atlas matching. In Workshop on 3D Segmentation in the Clinic: A Grand Challenge, MICCAI 2007, Brisbane (Australia).
12. ZHOU, X., KITAGAWA, T., OKUO, K., HARA, T., FUJITA, H., YOKOYAMA, R., KANEMATSU, M., HOSHI, H. Construction of a probabilistic atlas for automated liver segmentation in noncontrast torso CT images. International Congress Series, 2005, vol. 1281, p. 1169-1174.
13. LEE, J., KIM, N., LEE, H., SEO, J. B., WON, H. J., SHIN, Y. M., SHIN, Y. G., KIM, S. Efficient liver segmentation using a levelset method with optimal detection of the initial liver boundary from level-set speed images. Compute Methods Programs Biomed, Oct, 2007, vol. 88, no. 1, p. 26-38.
14. SEOL, Y., YU, J., KANG, T., CHOI, K, KIM, H., KIM, M. Resolving the initial contour problem of GVF snake in the sequential images. In Conf. Proc. IEEE Eng Med Biol Soc, 2007, p. 779-782.
15. OKADA, T., SHIMADA, R., SATO, Y., HORI, M., NAKAMOTO, M., CHEN, Y. W, NAKAMURA, H. Automated segmentation of the liver from 3D CT images using probabilistic atlas and multilevel statistical shape model. Academic Radiology, Nov. 2008, vol. 15, no. 11, p. 1390-1403.
16. VARMA, J., DURGAN, J., SUBRAMANYAN, K. Semi-automatic procedure to extract continued liver segments from multislice CT data. San Diego, (CA, USA), p. 561-568, 2003.
17. GRATZEL, C., FONG, T., GRANGE, S., BAUR, C. A Noncontact mouse for surgeon–computer interaction. Technology and Health Care Journal, IOS Press, 2004. vol. 12.
18. FEIED, C., GILLAM, M., WACHS, J., HANDLER, J., STERN, H., SMITH, M. A real-time gesture interface for hands-free control of electronic medical records. In AMIA Annual Symposium Proceedings. Washington (DC, USA), February 2006.
19. PAOLIS, L., PULIMENO, M., ALOISIO, G. Advanced visualization and interaction systems for surgical pre-operative planning. Journal of Computing and Information Technology, 2010, vol. 18, no 4, p. 385-392.
20. GALLO, L., CIAMPI, M. Wii remote-enhanced hand-computer interaction for 3D medical image analysis. In International Conference on Current Trends in Information Technology CTIT 2009. 2009, p. 85- 90.
21. COOPERSTOCK, J. R., WANG, G. Stereoscopic display technologies, interaction paradigms, and rendering approaches for neurosurgical visualization. In Stereoscopic Displays and Applications. San Jose (CA, USA), January 2009.
22. REITINGER, B., BORNIK, A., BEICHEL, R., SCHMALSTIEG, D. Liver surgery planning using virtual reality. IEEE Computer Graphics and Applications, Nov./Dec. 2006, vol. 26, no. 6, p. 36 to 47.
23. POPA, C., GORDAN, M., VLAICU, A., ORZA, B., OLTEAN, G. Computationally efficient algorithm for fuzzy rule-based enhancement on JPEG compressed color images. WSEAS Transactions on Signal Processing, May 2008, vol. 4 no. 5, p. 310 -319.
24. MALCOLM, J., RATHI, Y., YEZZI, A., TANNENBAUM, A. Fast approximate surface evolution in arbitrary dimension. In Proc. SPIE Medical Imaging 2008: Image Processing. 2008 February, 6914.
25. JIANG, C., ZHANG, X., MEINEL, C. Hybrid framework for medical image segmentation. In Proceedings of the 11th International Conference on Computer Analysis of Images and Patterns (CAIP'05). Springer-Verlag, Berlin, Heidelberg, 2005, p. 264-271.
26. PENNEBAKER, W. B., MITCHELL, J. L. JPEG: Still Image Compression Standard. New York: Van Nostrand Reinhold, 1993.
27. JIANG, J., FENG, G. The spatial relationship of DCT coefficients between a block and its sub-blocks. IEEE Transactions on Signal Processing, May 2002, vol. 50, no. 5, p.1160-1169.
28. PUN, C. M., ZHU, H. M. Textural image segmentation using discrete cosine transform. In Proceedings of the 3rd International Conference on Communications and Information Technology. Greece, December 2009.
29. SGOUROS, N., SANGRIOTIS, M., MAROULIS, D. Multiview image compression: future challenges and today’s solutions. In 1st International Scientific Conf. eRA T.E.I of Piraeus & University of Paisley. Tripoli, Sept. 16-17, 2006.
30. CHAN, R. K. W., LEE, M. C. 3D-DCT quantization as a compression technique for video sequences. In International Conference on Virtual Systems and MultiMedia, VSMM. 1997, p. 188.
31. VAPNIK, V. N. Statistical Learning Theory. New York: Wiley, 1998.
32. LIN, C. J., WENG, R. C. Probability estimates for multi-class classification by pair wise coupling. The Journal of Machine Learning Research archive, 2004, vol. 5.
33. PLATT, J. Probabilistic outputs for support vector machines and comparisons to regularized likelihood methods. In Advances in Large Margin Classifiers (Smola, A., Bartlett, P., Scholkopf, B., Schuurmans, D., Eds.). Cambridge (England, MA): MIT Press, 2000.
34. DANCIU, M., GORDAN, M., ORGHIDAN, R., SORANTIN, E., FLOREA, C., VLAICU, A. A fuzzy logic-guided virtual probe for 3D visual interaction applications. In IEEE International Conference on e-Health and Bioengineering (EHB 2011). Iasi (Romania), 24-26 November, 2011, p. 431- 434. ISBN: 978-606- 544-078-4.
35. CHIH-CHUNG CHANG, CHIH-JEN LIN LIBSVM, A library for support vector machines. ACM Transactions on Intelligent Systems and Technology, 2011. [Online] Software available at http://www.csie.ntu.edu.tw/~cjlin/libsvm.
36. CIECHOLEWSKI, M., OGIELA, M. R. Automatic segmentation of neoplastic hepatic disease symptoms in CT images. In Proceedings of the 4th International Conference on Modeling Decisions for Artificial Intelligence. Kitakyushu (Japan), 2007, p. 414-421.
37. CAMPADELLI, P., CASIRAGHI, E., PRATISSOLI, S. Fully automatic segmentation of abdominal organs from CT images using fast marching methods. In Proceedings of the 2008 21st IEEE International Symposium on Computer-Based Medical Systems, 2008, p. 554-559.
38. XU, D., LEE, J., RAICU, D. S., FURST, J. D., CHANNIN, D. Texture classification of normal tissues in computed tomography. In The 2005 Annual Meeting of the Society for Computer Applications in Radiology, June 2-5, 2005.
39. FORUZAN, A., AGHAEIZADEH, R., HORI, M., SATO, Y. Liver segmentation by intensity analysis and anatomical information in multi-slice CT images. International Journal of Computer Assisted Radiology and Surgery, 2009, vol. 4, no. 3, p. 287-297.
40. YUSSOF, W., BURKHARDT, H. 3D liver segmentation using hybrid segmentation techniques. In Proceedings of the International Conference of Soft Computing and Pattern Recognition, 2009, p. 404-408.
41. LUO, S., JIN, J. S., CHALUP, S. K., QIAN, G. A liver segmentation algorithm based on wavelets and machine learning. In International Conference on Computational Intelligence and Natural Computing CINC’09.Wuhan (China), 2009, vol. 2, p. 122-125.

Keywords: 3D liver segmentation, 3D DCT, blocks level volume segmentation, SVM, 3D human-computer interaction, segmentation refinement, 3D level set segmentation, neuro-fuzzy interaction

J. Mikulka, E. Gescheidtova, M. Kabrda, V. Perina [references] [full-text] [Download Citations]
Classification of Jaw Bone Cysts and Necrosis via the Processing of Orthopantomograms

The authors analyze the design of a method for automatized evaluation of parameters in orthopantomographic images capturing pathological tissues developed in human jaw bones. The main problem affecting the applied medical diagnostic procedures consists in low repeatability of the performed evaluation. This condition is caused by two aspects, namely subjective approach of the involved medical specialists and the related exclusion of image processing instruments from the evaluation scheme. The paper contains a description of the utilized database containing images of cystic jaw bones; this description is further complemented with appropriate schematic repre¬sentation. Moreover, the authors present the results of fast automatized segmentation realized via the live-wire method and compare the obtained data with the results provided by other segmentation techniques. The shape parameters and the basic statistical quantities related to the distribution of intensities in the segmented areas are selected. The evaluation results are provided in the final section of the study; the authors correlate these values with the subjective assessment carried out by radiologists. Interestingly, the paper also comprises a discussion presenting the possibility of using selected parameters or their combinations to execute automatic classification of cysts and osteonecrosis. In this context, a comparison of various classifiers is performed, including the Decision Tree, Naive Bayes, Neural Network, k-NN, SVM, and LDA classifica¬tion tools. Within this comparison, the highest degree of accuracy (85% on the average) can be attributed to the Decision Tree, Naive Bayes, and Neural Network classifiers

1. PAZDERA, J. The Basis of Oral Surgery. UP Olomouc, 2011. ISBN 978-80-244-2660-0.
2. CERNOCHOVA, P. The Diagnosis of Impacted Teeth. Prague: Grada Publishing, 2006, ISBN 80-247-1269-5.
3. MARCON, P., BARTUSEK, K., POKLUDOVA, M., DOKOUPIL, Z. Magnetic susceptibility measurement using 2D magnetic resonance imaging. Measurement Science and Technology, 2011, vol. 2011, no. 22, p. 1-8. ISSN: 0957- 0233.
4. MARCON, P., BARTUSEK, K., GESCHEIDTOVA, E., DOKOUPIL, Z. Diffusion MRI: magnetic field inhomogeneities mitigation. Measurement Science Review, 2012, vol. 12, no. 5, p. 205-212. ISSN: 1335- 8871.
5. DEDKOVA, J., OSTANINA, K. Two- dimensional tissue image reconstruction based on magnetic field data. Radioengineering, 2012, vol. 21, no. 3, p. 917-922. ISSN: 1210- 2512.
6. AYDEMIR, O., KAYIKCIOGLU, T. Wavelet transform based classification of invasive brain computer interface data. Radioengineering, 2011, vol. 20, no. 1, p. 31-38. ISSN: 1210-2512.
7. LI, CH., XU, CH., GUI, CH., FOX, M. D. Level set evolution without re-initialization: A new variational formulation. In IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR 2005). San Diego (CA, USA), 20-26 June 2005.
8. MIKULKA, J., GESCHEIDTOVA, E., BARTUSEK, K. Softtissues image processing: comparison of traditional segmentation methods with 2D active contour methods. Measurement Science Review, 2012, vol. 12, no. 4, p. 153-161. ISSN: 1335- 8871.
9. MIKULKA, J., GESCHEIDTOVA, E., BARTUSEK, K. Processing of MR slices of human liver for volumetry. In PIERS 2010 in Xi'an Proceedings. 2010, p. 202-204. ISBN: 978-1- 934142-12- 7.
10. CUTRONA, J., BONNET, N. Two methods for semi-automatic image segmentation based on fuzzy connectedness and watersheds. In Proceedings of the IASTED International Conference on Visualization, Imaging and Image Processing (VIIP 2001). Marbella (Spain), September 2001.
11. HLAVAC, V., SONKA, M. Computer Vision. Prague: Grada Publishing, 1992. ISBN 80-85424-67-3 (in Czech).
12. BAGGIO, D. L. GPGPU Based Image Segmentation Livewire Algorithm Implementation. [Online] Technological Institute of Aeronautics, Sao Jose dos Campos, 2007. Available at: http://gpuwire.googlecode.com/files/Master%20Thesis%20- %20Updated%20February%2015th.pdf
13. BURGET, R., UHER, V., MASEK, J. Trainable segmentation based on local-level and segment-level feature extraction. In Proceedings of the Ninth IEEE International Symposium on Biomedical Imaging: From Nano to Macro (ISBI'12). Barcelona (Spain), May 2-5, 2012.
14. UHER, V., BURGET, R. Automatic 3D segmentation of human brain images using data-mining techniques. In 35th International Conference on Telecommunications and Signal Processing TSP2012. Prague (Czech Rep.), July 2012.

Keywords: Image processing, image classification, follicular cyst, radicular cyst, live-wire, level set, OPG, RTG

C. Aydin, O. Oktay, A. U. Gunebakan, A. Ademoglu, R. K. Ciftci [references] [full-text] [Download Citations]
Role of Alpha Oscillations During Short Time Memory Task Investigated by Graph Based Partitioning

In this study, we investigate the clustering pattern of alpha band (8 Hz - 12 Hz) electroencephalogram (EEG) oscillations obtained from healthy individuals during a short time memory task with 3 different memory loads. The retention period during which subjects were asked to memorize a pattern in a square matrix is analyzed with a graph theoretical approach. The functional coupling among EEG electrodes are quantified via mutual information in the time-frequency plane. A spectral clustering algorithm followed by bootstrapping is used to parcellate memory related circuits and for identifying significant clusters in the brain. The main outcome of the study is that the size of the significant clusters formed by alpha oscillations decreases as the memory load increases. This finding corroborates the active inhibition hypothesis about alpha oscillations.

1. AVIYENTE, S. A measure of mutual information on the timefrequency plane. In IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP). Philadelphia (PA, USA), 2005, vol. 4, p. iv - 481.
2. AVIYENTE, S. Information-theoretic signal processing on the timefrequency plane and applications. In Proceedings of 2005 European Signal Processing Conference (EUSIPCO). Antalya (Turkey), 2005, p. 4 - 8.
3. BASAR, E., DEMIRALP, T., SCHURMANN, M., BASAREROGLU, C., ADEMOGLU, A. Oscillatory brain dynamics, wavelet analysis, and cognition.Brain and Language, 1999, vol. 66, no. 1, p. 146 - 183.
4. BELLEC, P., MARRELEC, G., BENALI, H. A bootstrap test to investigate changes in brain connectivity for functional MRI. Statistica Sinica, 2008, vol. 18, 1253 - 1268.
5. BELLEC, P., ROSA-NETO, P., LYTTELTON, O. C., BENALI, H., AND ALAN, C. Supplementary materials for Multi-Level Bootstrap Analysis of Stable Clusters in Resting-State fMRI. Journal of Nonparametric Statistics, 2010.
6. BUSCH, N. A., HERRMANN, C. S. Object-load and feature-load modulate EEG in a short-term memory task. NeuroReport, 2003, vol. 14, no. 13, p. 1721 - 1724.
7. CHEN, V., RUAN, S. Graph cut based segmentation of brain tumor from MRI images.International Journal on Sciences and Techniques of Automatic Control & Computer Engineering, 2009, vol. 3, no. 2, p. 1054 - 1063.
8. JENSEN, O., GELFAND, J., KOUNIOS, J., LISMAN, J. E. Oscillations in the alpha band (9-12 Hz) increase with memory load during retention in a short-term memory task. Cerebral cortex, 2002, vol. 12, no. 8, p. 877 - 882.
9. JOKISCH, D., JENSEN, O. Modulation of gamma and alpha activity during a working memory task engaging the dorsal or ventral stream. The Journal of Neuroscience: The Official Journal of the Society for Neuroscience, 2007, vol. 27, no. 12, p. 3244 - 3251.
10. KLIMESCH, W. EEG-alpha rhythms and memory processes. International Journal of Psychophysiology: Official Journal of the International Organization of Psychophysiology, 1997, vol. 26, no. 1-3, p. 319 - 340.
11. KLIMESCH, W. EEG alpha and theta oscillations reflect cognitive and memory performance: A review and analysis. Brain Research: Brain Research Reviews, 1999, vol. 29, no. 2-3, p. 169 - 195.
12. KLIMESCH, W., SAUSENG, P., HANSLMAYR, S. EEG alpha oscillations: the inhibition-timing hypothesis.Brain Research Reviews, 2007, vol. 53, no. 1, p. 63 - 88.
13. LU, C.-F., TENG, S., HUNG, C.-I., TSENG, P.-J., LIN, L.-T., LEE, P.-L., WU, Y.-T. Reorganization of functional connectivity during the motor task using EEG time-frequency cross mutual information analysis. Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology, 2011, vol. 122, no. 8, p. 1569 - 1579.
14. LUXBURG, U. A tutorial on spectral clustering. Statistics and Computing, 2007, vol. 17, no. 4, p. 395 - 416.
15. MODDEMEIJER, R. On estimation of entropy and mutual information of continuous distributions. Signal Processing, 1989, vol. 16, no. 3, p. 233 - 248.
16. MORMANN, F., LEHNERTZ, K., DAVID, P., ELGER, C. E. Mean phase coherence as a measure for phase synchronization and its application to the EEG of epilepsy patients. Physica D: Nonlinear Phenomena, 2000, vol. 144, no. 3-4, p. 358 - 369.
17. PALVA, S., PALVA, J. M. New vistas for alpha-frequency band oscillations. Trends in Neurosciences, 2007, vol. 30, no. 4, p. 150 - 158.
18. ROSSO, O., MARTIN, M., PLASTINO, A. Brain electrical activity analysis using wavelet-based informational tools. Physica A: Statistical Mechanics and its Applications, 2002, vol. 313, no. 3-4, p. 587 - 608.
19. SAUSENG, P., KLIMESCH, W., DOPPELMAYR, M., PECHERSTORFER, T., FREUNBERGER, R., HANSLMAYR, S. EEG alpha synchronization and functional coupling during top-down processing in a working memory task. Human Brain Mapping, 2005, vol. 26, no. 2, p. 148 - 155.
20. SCHEERINGA, R., PETERSSON, K. M., OOSTENVELD, R., NORRIS, D. G., HAGOORT, P., BASTIAANSEN, M. C. M. Trialby-trial coupling between EEG and BOLD identifies networks related to alpha and theta EEG power increases during working memory maintenance.NeuroImage, 2009, vol. 44, no. 3, p. 1224 - 1238.
21. SCHLOGL, A., KEINRATH, C., SCHERER, R., FURTSCHELLER, P. Information transfer of an EEG-based brain computer interface. In First International IEEE EMBS Conference on Neural Engineering. Capri Island (Italy), 2003, p. 641 - 644.
22. SHEN, X., PAPADEMETRIS, X., CONSTABLE, R. T. Graphtheory based parcellation of functional subunits in the brain from resting-state fMRI data. NeuroImage, 2010, vol. 50, no. 3, p. 1027 - 1035.
23. SHI, J., MALIK, J. Normalized cuts and image segmentation. IEEE Transactions on Pattern Analysis and Machine Intelligence, 2000, vol. 22, no. 8, p. 888 - 905.
24. SPORNS, O., HONEY, C. J. Small worlds inside big brains. Proceedings of the National Academy of Sciences of the United States of America, 2006, vol. 103, no. 51, p. 19219 - 19220.
25. TALLON-BAUDRY, C., BERTRAND, O., FISCHER, C. Oscillatory synchrony between human extrastriate areas during visual short-term memory maintenance. The Journal of Neuroscience: The Official Journal of the Society for Neuroscience, 2001, vol. 21, no. 20.
26. TULADHAR, A. M., TER HUURNE, N., SCHOFFELEN, J.-M., MARIS, E., OOSTENVELD, R., JENSEN, O. Parieto-occipital sources account for the increase in alpha activity with working memory load. Human Brain Mapping, 2007, vol. 28, no. 8, p. 785 - 792.
27. VAN DEN HEUVEL, M., MANDL, R., HULSHOFF POL, H. Normalized cut group clustering of resting-state FMRI data. Plos One, 2008, vol. 3, no. 4.

Keywords: EEG, Brain, Graph Theory, Memory, Spectral Clustering, Information Theory

Z. Biolek, D. Biolek, V. Biolkova [references] [full-text] [Download Citations]
Analytical Computation of the Area of Pinched Hysteresis Loops of Ideal Mem-Elements

The memory elements, memristor being the best known of them, driven by a periodical waveform exhibit the well-known pinched hysteresis loops. The hysteresis is caused by a memory effect which results in a nonzero area closed within the loop. This paper presents an analytical formula for the loop area. This formula is then applied to memory elements whose parameter-vs.-state maps are modeled in the polynomial form. The TiO2 memristor, a special subset of the above elements, is analyzed as a demonstration example.

1. Di VENTRA, M., PERSHIN, Y.V., CHUA, L. O. Circuit elements with memory: memristors, memcapacitors, and meminductors. Proceedings of the IEEE, 2009, vol. 97, no. 10, p. 1717 – 1724.
2. RADWAN, A. G., ZIDAN, M. A., SALAMA, K. N. On the mathematical modeling of memristors. In Proc. 22nd Int. Conf. on Microelectronics (ICM 2010). Cairo (Egypt), 2010, p. 284 – 287.
3. BIOLEK, Z., BIOLEK, D., BIOLKOVA, V. Computation of the area of memristor pinched hysteresis loop. IEEE Transactions on Circuits and Systems II: Express Briefs, 2012, no. 9, p. 607 – 611.
4. CHUA, L. O. Memristor–the missing circuit element. IEEE Transactions on Circuit Theory, 1971, vol. CT-18, no. 5, p. 507 – 519.
5. CHUA, L. O., KANG, S. M. Memristive devices and systems. Proc. of the IEEE, 1976, vol. 64, no. 2, p. 209 – 223.
6. BIOLEK, D., BIOLEK, Z., BIOLKOVA, V. Behavioral modeling of memcapacitor. Radioengineering, 2011, vol. 20, no. 1, p. 228 to 233.
7. BIOLEK, D., BIOLKOVA, V., KOLKA, Z. Mutators simulating memcapacitors and meminductors. In Proc of the 11th biennial IEEE Asia Pacific Conference on Circuits and Systems (APCCAS 2010). Kuala Lumpur (Malaysia), 2010, p. 800 – 803.
8. BAATAR, C., POROD, W., ROSKA, T. Cellular Nanoscale Sensory Wave Computing. Springer, 2011.
9. PERSHIN, Y. V., Di VENTRA, M. Memory effects in complex materials and nanoscale systems. Advances in Physics, 2011, vol. 60, p. 145 – 227.
10. BIOLEK, D., BIOLEK, Z., BIOLKOVA, V. PSPICE modeling of meminductor. Analog Integrated Circuits and Signal Processing, 2011, vol. 66, no. 1, p. 129 – 137.
11. CHUA, L. O. Resistance switching memories are memristors. Applied Physics A, 2011, no. 102, p. 765 – 783.
12. BIOLEK, D., BIOLEK, Z., BIOLKOVA, V., KOLKA, Z. Computing areas of pinched hysteresis loops of mem-systems in OrCAD PSPICE. Applied Mechanics and Materials, 2013, vols. 278-280, p. 1081-1090.
13. BIOLEK, D., BIOLEK, Z., BIOLKOVA, V. Pinched hysteretic loops of ideal memristors, memcapacitors and meminductors must be 'self-crossing'”. Electronics Letters, 2011, vol. 47, no. 25, p. 1385 – 1387.
14. STRUKOV, D. B., SNIDER, G. S., STEWART, D. R., WILLIAMS, R. S. The missing memristor found. Nature, 2008, vol. 453, p. 80 – 83.
15. BIOLEK, Z., BIOLEK, D., BIOLKOVA, V. SPICE model of memristor with nonlinear dopant drift. Radioengineering, 2009, vol. 18, no. 2, p. 210 – 214.

Keywords: Memory element, memristor, pinched hysteresis loop.

J. Dobes, J. Michal, V. Biolkova [references] [full-text] [Download Citations]
Multiobjective Optimization for Electronic Circuit Design in Time and Frequency Domains

The multiobjective optimization provides an extraordinary opportunity for the finest design of electronic circuits because it allows to mathematically balance contradictory requirements together with possible constraints. In this paper, an original and substantial improvement of an existing method for the multiobjective optimization known as GAM (Goal Attainment Method) is suggested. In our proposal, the GAM algorithm itself is combined with a procedure that automatically provides a set of parameters -- weights, coordinates of the reference point -- for which the method generates noninferior solutions uniformly spread over an appropriately selected part of the Pareto front. Moreover, the resulting set of obtained solutions is then presented in a suitable graphic form so that the solution representing the most satisfactory tradeoff can be easily chosen by the designer. Our system generates various types of plots that conveniently characterize results of up to four-dimensional problems. Technically, the procedures of the multiobjective optimization were created as a software add-on to the CIA (Circuit Interactive Analyzer) program. This way enabled us to utilize many powerful features of this program, including the sensitivity analyses in time and frequency domains. As a result, the system is also able to perform the multiobjective optimization in the time domain and even highly nonlinear circuits can be significantly improved by our program. As a demonstration of this feature, a multiobjective optimization of a C-class power amplifier in the time domain is thoroughly described in the paper. Further, a four-dimensional optimization of a video amplifier is demonstrated with an original graphic representation of the Pareto front, and also some comparison with the weighting method is done. As an example of improving noise properties, a multiobjective optimization of a low-noise amplifier is performed, and the results in the frequency domain are shown. Finally, a necessity of a use of metaheuristic methods at least with a combination with the classical ones is demonstrated.

1. MIETTINEN, K. K. Nonlinear Multiobjective Optimization. Boston (MA, USA): Kluwer Academic Publishers, 1998.
2. KOLO, B. Single & Multiple Objective Optimization. Weatherford (OK, USA): Weatherford Press, 2010.
3. COLLETTE, Y., SIARRY, P. Multiobjective Optimization (Principles and Case Studies). 2 nd ed. Berlin (Germany): Springer, 2004.
4. SHORBAGY, M., MOUSA, A. A. A., FATHI, W. Hybrid Particle Swarm Algorithm for Multiobjective Optimization (Integrating Particle Swarm Optimization with Genetic Algorithms for Multiobjective Optimization). Saarbrucken (Germany): LAP (Lambert Academic ¨ Publishing), 2011.
5. BRUSCHI, P., NAVARRINI, D., TARROBOIRO, G., RAFFA, G. Acomputationally efficient technique for the optimization of two stage CMOS operational amplifiers. In Proceedings of the 16th European Conference on Circuit Theory and Design.Cracow (Poland), 2003, p. 305 - 308.
6. MICHAL, J., DOBES, J. Electronic circuit design using multiobjec- ˇ tive optimization. In Proceedings of the 50th IEEE Midwest Symposium on Circuits and Systems. Montreal (Canada), 2007, p. 734 - ´ 737.
7. COLEMAN, T. F., ZHANG, Y. Optimization Toolbox 4 – User’s Guide. Natick (MA, USA): The MathWorks, Inc., 2008.
8. MOOSAVIAN, S. A. A., GHAFARI, A., SALIMI, A., ABDI, N. Non-linear multiobjective optimization for control of hydropower plants network. InProceedings of the IEEE International Conference on Advanced Intelligent Mechatronics. Xi’an (China), 2008, p. 1278 - 1283.
9. DOBES, J., BIOLKOVA, V. Reliable and efficient procedure for ´ steady-state analysis of nonautonomous and autonomous systems. Radioengineering, 2012, vol. 21, no. 1, p. 374 - 385.
10. DOBES, J. Advanced types of the sensitivity analysis in frequency ˇ and time domains. AEU – International Journal of Electronics and ¨ Communications, 2009, vol. 63, no. 1, p. 52 - 64.
11. ALLSTOT, D., CHOI, K., PARK, J.Parasitic-Aware Optimization of CMOS RF Circuits. New York (USA): Kluwer Academic Publishers, 2003.
12. HOROWITZ, P., HILL, W. The Art of Electronics.Cambridge (UK): Cambridge University Press, 1989.
13. DOBES, J., MICHAL, J., PANKO, V., POSPISIL, L. Reliable pro- ˇ cedure for electrical characterization of MOS-based devices, SolidState Electronics, 2010, vol. 54, no. 10, p. 1173 - 1184.
14. TLELO-CUAUTLE, E., GUERRA-GOMEZ, I., DE LA FRAGA, L. G., FLORES-BECERRA, G., POLANCO-MARTAGON, S., ´ FAKHFAKH, M., REYES-GARCIA, C. A., RODRIGUESGOMEZ, G., REYES-SALGADO, G. Evolutionary algorithms in ´ the optimal sizing of analog circuits. Intelligent Computational Optimization in Engineering, Studies in Computational Intelligence. Berlin (Germany): Springer, 2011, vol. 366, p. 109 - 138.
15. FAKHFAKH, M., SALLEM, A., BOUGHARIOU, M., BENNOUR, S., BRADAI, E., GADDOUR, E., LOULOU, M. Analogue circuit optimization through a hybrid approach. Intelligent Computational Optimization in Engineering, Studies in Computational Intelligence. Berlin (Germany): Springer, 2011, vol. 366, p. 297 - 327.
16. MOUSA, A. A. A. Study on Multiobjective Optimization Using Improved Genetic Algorithm (Methodology and Application). Saarbrucken (Germany): LAP (Lambert Academic Publishing), 2011.
17. MIYAZAKI, R., HAMADA, N., NAGATA, Y., ONO, I. A new Pareto frontier covering strategy in FS-MOGA for multi-objective function optimization. In Proceedings of the 6th International Conference on Soft Computing and Intelligent Systems=13th International Symposium on Advanced Intelligent Systems. Kobe (Japan), 2012, p. 1888 - 1893.
18. HIRANO, H., YOSHIKAWA, T. A study on two-step search using global-best in PSO for multi-objective optimization problems. In Proceedings of the 6th International Conference on Soft Computing and Intelligent Systems=13th International Symposium on Advanced Intelligent Systems. Kobe (Japan), 2012, p. 1894 - 1897.
19. CHIBA, K. Performance comparison of evolutionary algorithms applied to hybrid rocket problem. In Proceedings of the 6th International Conference on Soft Computing and Intelligent Systems=13th International Symposium on Advanced Intelligent Systems. Kobe (Japan), 2012, p. 1673 - 1678.
20. PAPA, D. A., MARKOV, I. L. Multi-Objective Optimization in Physical Synthesis of Integrated Circuits.New York (NY, USA): Springer, 2013.
21. ZHOU, Y., GAD, E., NAKHLA, M. S., ACHAR, R. Structural characterization and efficient implementation technique for A-stable high-order integration methods. IEEE Transactions on ComputerAided Design of Integrated Circuits and Systems, 2012, vol. 31, no. 1, p. 101 - 108.
22. DOBES, J., GRABNER, M. Novel HEMT models with improved ´ higher-order derivatives and extracting their parameters using multibias S-parameters. InProceedings of the 33rd IEEE Compound Semiconductor Integrated Circuit Symposium. Waikoloa, Big Island (HI, USA), 2011, p. 189 - 192.

Keywords: Multiobjective optimization, Pareto front, Pareto optimal set, noninferior solutions, goal attainment method, metaheuristics, simulated annealing, hybrid methods.

De-zhi Wang, Ke-feng Zhang, Xue-cheng Zou [references] [full-text] [Download Citations]
High Current Matching over Full-Swing and Low-Glitch Charge Pump Circuit for PLLs

A high current matching over full-swing and low-glitch charge pump (CP) circuit is proposed. The current of the CP is split into two identical branches having one-half the original current. The two branches are connected in source-coupled structure, and a two-stage amplifier is used to regulate the common-source voltage for the minimum current mismatch. The proposed CP is designed in TSMC 0.18µm CMOS technology with a power supply of 1.8 V. SpectreRF based simulation results show the mismatch between the current source and the current sink is less than 0.1% while the current is 40 µA and output swing is 1.32 V ranging from 0.2 V to 1.52 V. Moreover, the transient output current presents nearly no glitches. The simulation results verify the usage of the CP in PLLs with the maximum tuning range from the voltage-controlled oscillator, as well as the low power supply applications.

1. SIMKA, M., DRUTAROVSKΎ, M., FISCHER, V. Testing of PLL-based true random number generator in changing working conditions. Radioengineering, 2011, vol. 20, no. 1, p. 94-101.
2. CHOI, Y. S., HAN, D. H. Gain-boosting charge pump for current matching in phase-locked loop. IEEE Transactions on Circuits and Systems II, 2006, vol. 53, no. 10, p. 1022-1025.
3. LEE, J. S., KEEL, M. S., LIM, S. I., et al. Charge pump with perfect current matching characteristics in phase-locked loops. Electronics Letters, 2000, vol. 36, no. 11, p. 1907-1908.
4. SUN, Y., SIEK, L., SONG, P. Y. Design of a high performance charge pump circuit for low voltage phase-locked loops. In IEEE International Symposium on Integrated Circuits. Singapore, 2007, p. 271-274.
5. CHENG, S. F., TONG, H. T., et al. Design and analysis of an ultra high-speed glitch-free fully differential charge pump with minimum output current variation and accurate matching. IEEE Transactions on Circuits and Systems, 2007, vol. 53, no. 9, p. 843 to 847.
6. TSITOURAS, A., PLESSAS, F., BIRBAS, B., et al. A 1V CMOS programmable accurate charge pump with wide output voltage range. Microelectronics Journal, 2011, vol. 42, no. 9, p. 1082 to 1089.
7. CHARLES, C. T., ALLSTOT, D. J. A buffered charge pump with zero charge sharing. In IEEE International Symposium on Circuits and Systems. Seattle (USA, WA), 2008, p. 2633-2636.
8. BAHREYNI, B., FILANOVSKY, I. M., SHAFAI, C. A novel design for deadzone-less fast charge pump with low harmonic content at the output. In IEEE Midwest Symposium on Circuits and Systems. Oklahoma, 2002, p. 397-400.
9. HWANG, I. C., BAE, S. G. Low-glitch, high-speed charge-pump circuit for spur minimization. Electronics Letters, 2009, vol. 45, no. 28, p. 1273-1274.
10. LEE, H. I., AHN, T. W., JUNG, D. Y., et al. Scheme for no dead zone, fast PFD design. Korean Physical Society, 2002, vol. 40, no. 4, p. 543-545.
11. BANERJEE, D. PLL Performance, Simulation and Design. National Semiconductor, 2006.
12. FENG, K. D., LEE, J. C. Spark current in charge pump of phase lock loop. In IEEE Custom Integrated Circuits Conference. Santa Clara, 2005, p. 199-202.
13. YOUNG, I. A PLL clock generator with 5 to 110 MHz of lock range for microprocessors. IEEE J. Solid-State Circuits. 1992, vol. 27, no. 2, p. 1599-1607.
14. JALALI, M. S., BAKHTIAR, S., MIRABBASI, S. A charge-pump with a high output swing for PLL and CDR applications. In IEEE International Conference on NEWCAS. Montreal (QC, Canada), 2010, p. 297-300.
15. RHEE, W. Design of high-performance CMOS charge pump in phase-locked loops. In IEEE Custom Integrated Circuits Conference. Santa Clara, 1999, p. 545-548.

Keywords: Charge pump, two current branches, source-coupled, voltage regulate, low-glitch, full swing

M. Bothra, R. Pandey , N. Pandey , S. K. Paul [references] [full-text] [Download Citations]
Operational Trans-Resistance Amplifier Based Tunable Wave Active Filter

In this paper, Operational Trans-Resistance Amplifier (OTRA) based wave active filter structures are presented. They are flexible and modular, making them suitable to implement higher order filters. The circuits implement the resistors using matched transistors, operating in linear region, making them well suited for IC fabrication. They are insensitive to parasitic input capacitances and input resistances due to the internally grounded input terminals of OTRA. As an application, a doubly terminated third order Butterworth low pass filter has been implemented, by substituting OTRA based wave equivalents of passive elements. PSPICE simulations are given to verify the theoretical analysis.

1. SHAUMANN, R., VAN VALKENBURG, M. E. Design of Analog Filters. Oxford (UK): Oxford University Press, 2001.
2. WUPPER, H., MEERKOTTER, K., New active filter synthesis based on scattering parameters. IEEE Transactions on Circuits and Systems, 1975, vol. 22, no. 7, p. 594 - 602.
3. HWANG, Y. S., WU, D. S., CHEN, J. J., SHIH, C. C., CHOU, W. S. Realisation of high order OTRA-MOSFET-C active filters. Circuits, Systems Signal Processing, 2007, vol. 26, no. 2, p. 281 - 291.
4. TINGLEFF, J., TOUMAZOU, C. A 5th order lowpass current mode wave active filter in CMOS technology. Analog Integrated Circuits and Signal Processing, 1995, vol.7, p. 131 - 137.
5. SPANIDOU, A., PSYCHALINOS, C. Current amplifier-based wave filters. Circuits, Systems Signal Processing, 2005, vol. 24, no. 3, p. 303 - 313.
6. SOULIOTIS, G., HARITANTIS, I. Current-mode differential wave active filters. IEEE Transactions on Circuits and Systems-I: Regular Papers, 2005, vol. 52, no. 1, p. 93 - 98.
7. FRAGOULIS, N. SOULIOTIS, G., BESIRIS, D., GIANNAKOPOULOS, K. Field-programmable analogue array design based on the wave active filter design method. International Journal of Electronics and Communication (AEU), 2009, vol.63, p. 889 - 895.
8. HARITANTIS, I., CONSTANTINIDES, A., DELIYANNIS, T. Wave active filters. IEE Proceedings, 1976, vol. 123, no. 7, p. 676 - 682.
9. KOUKOU, G., PSYCHALINOS, C. Modular filter structures using current feedback operational amplifiers. Radioengineering, 2010, vol. 19, no. 4, p. 662 - 666.
10. PANDEY, N., KUMAR, P. Realization of resistorless wave active filters using differential voltage current controlled conveyor transconductance amplifier. Radioengineering, 2011, vol. 20, no. 4, p. 911 - 916.
11. TOUMAZOU, C., LIDGEY, F. J., HAIGH, D. G. Analogue IC Design: The Current Mode Approach. Stevenage (UK): Peregrinus, 1990.
12. CHEN, J., TSAO, H., CHEN, C. Operational trans-resistance amplifier using CMOS technology. Electronics Letters, 1992, vol. 28, no. 22, p. 2087 - 2088.
13. SALAMA, K. N., SOLIMAN, A. M. CMOS OTRA for analog signal processing applications. Microelectronics Journal, 1999, vol. 30, p. 235 - 245.
14. BIOLEK, D., BIOLKOVA, V. Tunable CDTA-based ladder filters. In Proceedings of 2nd WSEAS ICEASCS. Singapore, 2003, p. 462 - 466.
15. JIRASEREE-AMORNKUN, A., FUJII, N., SURAKAMPONTORN, W. Realization of electronically tunable ladder filters using multi output current controlled conveyors. In Proceedings of the 2003 International Symposium on Circuits and Systems (ISCAS). Bangkok (Thailand), 2003, vol. I, p. I-541 - I-544.
16. JAIKLA, W., SITIPRUCHYANUN, M. A systematic design of electronically tunable ladder filters employing DO-OTAs. In Proceedings of 4th International Conference on Electrical Engineering / Electronics, Computer, Telecommunications and Information Technology (ECTI-CON). Chiang Rai (Thailand), 2007, p. 61 - 64.
17. MOSTAFA, H., SOLIMAN, A. M. A modified CMOS realization of the operational transresistance amplifier (OTRA). Frequenz, 2006, vol. 60, no. 3-4, p. 70 - 77.

Keywords: Wave active filter, OTRA, scattering parameters, ladder, tunable filter

J. Nahlik, J. Hospodka, P. Sovka, B. Psenicka [references] [full-text] [Download Citations]
Implementation of a Two-Channel Maximally Decimated Filter Bank using Switched Capacitor Circuits

The aim of this paper is to describe the implementation of a two-channel filter bank (FB) using the switched capacitor (SC) technique considering real properties of operational amplifiers (OpAmps). The design procedure is presented and key recommendations for the implementation are given. The implementation procedure describes the design of two-channel filter bank using an IIR Cauer filter, conversion of IIR into the SC filters and the final implementation of the SC filters. The whole design and an SC circuit implementation is performed by a PraCAn package in Maple. To verify the whole filter bank, resulting real property circuit structures are completely simulated by WinSpice and ELDO simulators. The results confirm that perfect reconstruction conditions can be almost accepted for the filter bank implemented by the SC circuits. The phase response of the SC filter bank is not strictly linear due to the IIR filters. However, the final ripple of a magnitude frequency response in the passband is almost constant, app. 0.5 dB for a real circuit analysis.

1. HOSPODKA, J., SOVKA, P., PSENICKA, B. Design and realization of a filter bank by switched capacitor technique. In 20th European Conference on Circuit Theory and Design (ECCTD 2011). Linko¨ping (Sweden), 2011, p. 782 - 785.
2. MADISETTI, V. K., WILLIAMS, D. B. (eds.) The Digital Signal processing Handbook. Boca Raton (USA): CRC Press 1998.
3. CROCHIERE, R. E., RABINER, L. R. Multirate Digital Signal Processing. New Jersey (USA): Prentice-Hall, 1983.
4. FLIEGE, N. J.Multirate Digital Signal Processing. New York (USA): Wiley, 1994.
5. VAIDYANATHAN, P. P. Multirate Systems and Filter Bank. New Jersey (USA): Prentice-Hall, 1993.
6. PHOONG, S., KIM, C. W., VAIDYANATHAN, P. P., ANSARI, R. A new class of two-channel biorthogonal filter banks and wavelet bases.IEEE Transactions on Signal Processing , 1995, vol. 43, no. 3, p. 649 - 665.
7. LOWENBERG, P., JOHANSON, H., WANHAMMER, L. Twochannel hybrid analog/digital filter banks with alias-free subbands. In Proceedings of the 43rd IEEE Midwest Symposium on Circuits and Systems. Lansing (USA), 2000, vol. 3, p. 1162 - 1165.
8. GREGORIAN, R., MARTIN, K. W. Switched-capacitor circuit design. Proceedings of the IEEE, 1983, vol. 71, no. 8, p. 941 - 966.
9. TSAI-CHUNG YU, CHUNG-YU WU, SHIN-SHI CHANG Realizations of IIR/FIR and N-path filters using a novel switched-capacitor technique.IEEE Transactions on Circuits and Systems, 1990, vol. 37, no. 1, p. 91 - 406.
10. LIN, J., SHAMMA, S. A., EDWARDS, T. G. Cochlear Filter Bank with Switched-Capacitor Circuits. United States Patent No. US005331222A, 1994.
11. BOSSHART, P. W. A multiplexed switched capacitor filter bank. IEEE Journal of Solid-State Circuits, 1980, vol. sc-15, no. 6, p. 939 - 945.
12. KURAISHI, Y., NAKAYAMA, K., MIYADERA, K., OKAMURA, T. A single-chip 20-channel speech spectrum analyser using a multiplexed switched-capacitors filter bank.IEEE Journal of Solid-State Circuits, 1984, vol. sc-19, no. 6, p. 964 - 970.
13. VICH, R. Z Transform Theory and Applications. Boston (USA): D. Reidel Publishing Company, 1987.
14. ANANDA MOHAN, P. V., RAMACHANDRAN, V., SWAMY, M. N. S. Switched Capacitor Filters: Theory, Analysis and Design. New Jersey (USA): Prentice Hall, 1995.
15. BICAK, J., HOSPODKA, J. PraCAn – Maple package for symbolic circuit analysis. In Digital Technologies. Zˇilina (Slovakia), 2008.
16. BICAK, J., HOSPODKA, J. Frequency response of switched circuits in SPICE. In The 16th European Conference on Circuits Theory and Design (ECCTD). Krako´w (Poland), 2003, vol. I, p. 333 - 336.
17. SMITH, M. WinSpice User’s Manual[Online] 2009. Cited 2012-10- 06. Available at: http://www.winspice.com .
18. Mentor Graphics Corp. Available at: http://www.mentor.com .
19. JUNG, W. Using the LTC OpAmp Macromodels, AN48 [Online] 1991, Cited 2012-10-06. Available at: http://cds.linear.com/ .
20. Linear Teachnology, LT1055 Datasheet [Online], 2004. Cited 2012- 10-06. Available at: http://cds.linear.com/ .
21. Linear Teachnology,LT1055 Spice model[Online], 2005. Cited 2012- 10-06. Available at: http://cds.linear.com/ .
22. ALEXANDER, M., BOWERS, D. F. Spice-Compatible Op Amp Macro-Models. [Online], 1990. Cited 2012-10-06. Available at: http://www.analog.com/ .
23. Analog devices, Inc., AD8033 Data Sheet, Rev C. [Online], 2008. Cited 2012-10-06. Available at: http://www.analog.com/ .
24. Analog devices, Inc., AD8033 Spice Macro-model, Rev E [Online], 2012. Cited 2012-10-06. Available at: http://www.analog.com/ .

Keywords: Filer Bank Realization, SC Circuit, Filter Synthesis

R. Arya, G. Souliotis, S. Vlassis, C. Psychalinos [references] [full-text] [Download Citations]
0.5V 3^rd-order Tunable g_m-C Filter

This paper proposes a 3^rd-order g_m-C filter that operates with the extremely low voltage supply of 0.5V. The employed transconductor is capable for operating in an extremely low voltage power supply environment. A benefit offered by the employed transconductor is that the filter’s cut-off frequency can be tuned, through a dc control current, for relatively large ranges. The filter structure was designed using normal threshold transistors of a triple-well 0.13μm CMOS process and is operated under a 0.5V supply voltage; its behavior has been evaluated through simulation results by utilizing the Analog Design Environment of the Cadence software.

1. TSIVIDIS, Y., BANU, M. KHOURY J. Continuous-time MOSFET-C filters in VLSI. IEEE Journal of Solid-State Circuits, 1986, vol. 21, no. 1, p.15–30.
2. RODRIGUES-VASQUEZ, A., LINARES-BARRANCO, B., HUERTAS, J. SANCHEZ-SINENSIO, E. On the design of voltage controlled sinusoidal oscillators using OTA’s. IEEE Trans. Circuit and Systems, 1990, vol. 37, no. 2, p. 198-211.
3. NAUTA, B. A CMOS transconductance-C filter technique for very high frequencies. IEEE Journal of Solid-State Circuits, 1992, vol. 27, no. 2, p. 142 - 153.
4. ANDREANI, P., MATTISSON, S. On the use of Nauta’s transconductor in low-frequency CMOS gm-C bandpass filters. IEEE Journal of Solid-State Circuits, 2002, vol. 37, no. 2, p. 114 -124.
5. LEE, T., PAN, H. A low-voltage CMOS transconductor for VHF continuous-time filters. In Proceedings of the IEEE International Symposium on Circuits and Systems (ISCAS). Hong Kong, 1997, p. 213 - 216.
6. MUÑOZ, F., TORRALBA, A., CARVAJAL, R. G., TOMBS, J., RAMIREZ-ANGULO, J. Floating-gate-based tunable low-voltage linear transconductor and its application to HF gm-C filters design. IEEE Transactions on Circuits and Systems-II, 2001, vol. 48, no. 1, p. 106 - 110.
7. SUADET, A., KASEMSUWAN, V. A CMOS inverter-based class-AB pseudo differential amplifier for HF applications. In Proc. of the IEEE International Conf. of Electron Devices and Solid- State Circuits (EDSSC). Hong Kong (China), 2010, p. 1 - 4.
8. BARTHELEMY, H., MEILLERE, S., GAUBERT, J., DAHAESE, N., BOURDEL, S. OTA based on CMOS inverters and application in the design of tunable bandpass filter. Analog Integrated Circuits and Signal Processing, 2008, vol. 57, no. 3, p. 169 - 178.
9. VLASSIS, S. 0.5 V CMOS inverter-based tunable transconductor. Analog Integrated Circuits and Signal Processing, 2012, vol. 72, no. 1, p. 289 - 292.
10. VITTOZ, E. Weak inversion in analog and digital circuits. In System Level Implications on Circuit Design Workshop (CCCD), 2003, Lund (Sweden).
11. SANTHANALAKSHMI, M., VANATHI, P. T. An improved OTA for a 2nd order gm-C low pass filter. European Journal of Scientific Research, 2011, vol. 66, no.1, p. 75 - 84.
12. CARILLO, J. M., DOMINGUEZ, M. A., DUQUE-CARRILLO, J. F. 1.2V fully differential OTA-C lowpass filter based on bulkdriven MOS transistors. In Proc. of the 20th European Conf. on Circuit Theory and Design (ECCTD). Linkoping (Sweden), 2011.
13. HORI, S., MAEDA, T., MATSUNO, N., HIDA, H. Low-power widely tunable gm-C filter with an adaptive DC-blocking, triodebiased MOSFET transconductor. In Proceeding of the 30th European Solid-State Circuits Conference (ESSCIRC). Leuven, (Belgium), 2004, p. 99 - 102.
14. LO, T. Y., HUNG, C. C. Multi-mode Gm-C channel selections filter for mobile applications in 1V supply voltage. IEEE Transactions on Circuits and Systems-II: Express briefs, 2008, vol. 55, no. 4, p. 314 - 318.
15. STEHR, U., HENKEL, F., DALLIGE, L., WALDOW, P. A fully differential CMOS integrated 4th order reconfigurable GM-C low pass filter for mobile communication. In Proceeding of the 11th

Keywords: G_m-C filters, analog filters, low voltage circuits

S. Surav Yilmaz, A.T. Tola, R. Arslanalp [references] [full-text] [Download Citations]
A Novel Second-Order All-Pass Filter Using Square-Root Domain Blocks

In this study, a new second order all-pass filter is synthesized in the square-root domain by using the state-space method. The proposed second order all-pass filter is constituted by current mirrors, current sources, current-mode square-root circuits and capacitors. The pole frequency of the filter can be tuned electronically by varying the values of the current sources of this circuit. The filter is simulated in PSpice using 0.35um CMOS technology parameters. Quality factor of the circuit is selected as 5 and supply voltage is set to 2.7V. The simulation results show that the proposed circuit has the merits of electronic tunability. We also performed noise, THD and Monte-Carlo analyses. Various simulation results are presented to show the effectiveness of the proposed circuit.

1. MULDER, J., WOERD, A. C., SERDIJN, W. A., ROERMUND, H. M. General current-mode analysis method for translinear filters. IEEE Transactions on Circuits and Systems I: Fundamental Theory and Applications, 1997, vol. 44, no. 3, p. 193-197.
2. YU, G. J., LIN, Y. S. Low voltage tunable square-root domain bandpass filter with translinear loop technique in biomedical engineering. Life Science Journal-Acta Zhengzhou University Overseas Edition, 2010, vol. 7, no. 1, p. 30-33.
3. FREY, D. R. Log-domain filtering: an approach to current-mode filtering. IEE Proceedings-g, 1993, vol. 140, no. 6, p. 406-416.
4. FREY, D. R. Exponential state space filters: A generic current mode design strategy. IEEE Transactions on Circuits and Systems I: Fundamental Theory and Applications, 1996, vol. 43, p. 34-42.
5. SEEVINCK, E. Companding current mode integrator: A new circuit principle for continuous-time monolithic filters. Electronics Letters, 1990, vol. 26, no. 24, p. 2046-2047.
6. ESKIYERLI, M. H., PAYNE, A. J. “Square root domain” filter design and performance. Analog Integrated Circuits and Signal Processing, 2000, vol. 22, p. 231-243.
7. ESKIYERLI, M. H., PAYNE, A. J., TOUMAZOU, C. State-space synthesis of biquads based on the MOSFET square law. In IEEE International Symposium on Circuits and Systems, 1996, vol. 1, p. 321-324.
8. LOPEZ-MARTIN, A., CARLOSENA, A. Systematic design of companding systems by component substitution. Analog Integrated Circuits and Signal Processing, 2001, vol. 28, no. 1, p. 91 to 106.
9. PSYCHALINOS, C., VLASSIS, S. A systematic design procedure for square-root domain circuits based on the signal flow graph approach. IEEE Transactions on Circuits and Systems, 2002, vol. 49, no. 12, p. 1702–1712.
10. OLMEZ, S., CAM, U. A novel square-root domain realization of first order all-pass filter. Turkish Journal of Electrical Engineering and Computer Sciences, 2010, vol. 18, no. 1, p. 141-146.
11. CAKIR, C., CAM, U., CICEKOGLU, O. Novel allpass filter configuration employing single OTRA. IEEE Trans. Circuits Syst. II, Analog Digit. Signal Process., 2005, vol. 52, no. 3, p. 122 -125.
12. MAHESHWARI, S., KHAN, I. A. Simple first-order translinear-C current mode all pass filter section. International Journal of Electronic, 2003, vol. 90, p. 79-85.
13. TOLA, A. T., ARSLANALP, R., SURAV YILMAZ, S. Current mode high-frequency KHN filter employing differential class AB log domain integrator. International Journal of Electronics and Communications (AEU), 2009, vol. 63, p. 600-608.
14. YUCE, E., PAL, K., MINAEI, S. A high input impedance voltagemode all-pass/notch filter using a single variable gain current conveyor. Journal of Circuits, Systems, and Computers (JCSC), 2008, vol. 17, no. 5, p. 827-834.
15. SALAWU, R. I. Realization of an all-pass transfer function using the second-generation current conveyor. In Proc. Inst. Elect, Electron. Engrs, 1980, vol. 68, no. 1, p. 183–184.
16. METIN, B., CICEKOGLU, O. Component reduced all-pass filter with a grounded capacitor and high-impedance input. Internaional Journal of Electronics, 2009, vol. 96, p. 445-455.
17. KESKIN, A. U., PAL, K., HANCIOGLU, E. Resistorless first-order all-pass filter with electronic tuning. International Journal of Electronics and Communications (AEU), 2008, vol. 62, p. 304 to 306.
18. BIOLEK, D., BIOLKOVA, V. First-order voltage-mode all-pass filter employing one active element and one grounded capacitor. Analog Integrated Circuit Signal Processing, 2010, vol. 65, p. 123 to 129.
19. BHUSAN, M., NEWCOMB, R. W. Grounding of capacitors in integrated circuits. Electronic Letters, 1967, vol. 3, p. 148–149.
20. LAHIRI, A., CHOWDHURY, A. A novel first-order current-mode all-pass filter using CDTA. Radioengineering, 2009, vol. 18, no. 3, p. 300-305.
21. HERENCSAR, N., KOTON, J., VRBA, K., METIN, B. Novel voltage conveyor with electronic tuning and is application to resistorless all-pass filter. In The 34th International Conference on Telecommunications and Signal Processing (TSP). Budapest (Hungary), 2011, p. 265-268.
22. FREY, D. R. State-space synthesis and analysis of log-domain filters. IEEE Transactions on Circuits and Systems II: Analog and Digital Signal Processing, 1998, vol. 45, no. 9, p. 1205-1211.
23. ARSLANALP, R., TOLA, A. T. Electronically tunable square-root domain filter circuit. In IEEE 15th Signal Processing and Communications Applications Conference. Eskisehir (Turkey), 2007.
24. ARSLANALP, R., TOLA, A. T. State space representation for log domain filtering synthesis. Indian Journal of Pure & Applied Physics, 2009, vol. 47, p. 745-752.
25. ARSLANALP, R., TOLA, A. T. ELIN Filtrelerin Genel Sentez Teorisi ve Gerçeklenme Şartları’. Pamukkale University Journal of Engineering Science, 2007, vol. 13, no.1, p. 47-56.
26. YU, G. J., HUANG, C. Y., LIU, B. D., CHEN, J. J. Design of square-root domain filters. Analog Integrated Circuits and Signal Processing, 2005, vol. 43, p. 49–59.

Keywords: Square-root domain filter, second order all-pass filter, translinear circuits.

P. Zahradnik, M. Vlcek [references] [full-text] [Download Citations]
Notch Filtering Suitable for Real Time Removal of Power Line Interference

This paper presents a high performance notch filtering for real time suppression of power line interference in a general signal. The disturbing signal is suppressed using an optimal notch FIR filter with tunable notch frequency. The tuning of the filter preserves its selectivity, most importantly the specified attenuation at the notch frequency. One example and two Matlab functions demonstrate the performance, robustness and usefulness of the proposed procedure for the design and tuning of optimal notch FIR filters suitable in the real time notch filtering.

1. MARTENS, S. M. M., MISCHI, M., OEI, S. G., BERGMANS, J. W. M. An improved adaptive power line interference canceller for electrocardiography. IEEE Transactions on Biomedical Engineering, 2006, vol. 53, no. 11, p. 2220 - 2231.
2. CHAVAN, M. S., AGARWALA, R., UPLANE, M. D. Design and implementation of digital FIR equiripple notch filter on ECG signal for removal of power line interference. WSEAS Transactions on Signal Processing, 2008, vol. 4, no. 4, p. 221 - 230.
3. OLGUIN, D. O., LARA, F. B., CHAPA, S. O. M. Adaptive notch filter for EEG signals based on the LMS algorithm with variable step-size parameter. In Proceedings of the 39th International Conference on Information Sciences and Systems. Baltimore (USA), 2005.
4. LEE, J. W., LEE, G. K. Design of an adaptive fwith a dynamic structure for ECG signal processing. International Journal of Control, Automation and Systems, 2005, vol. 3, no. 1, p. 137 - 142.
5. KUMAR, Y., MALIK, G. K. Performance analysis of different filters for power line interface reduction in ECG signal. International Journal of Computer Applications, 2010, vol. 3, no. 7, p. 1 - 6.
6. FERDJALLAH, M., BARR, R. E. Adaptive digital notch filter design on the unit circle for the removal of powerline noise from biomedical signals. IEEE Transactions on Biomedical Engineering, 1994, vol. 41, no. 6, p. 529 - 536.
7. ZAHRADNIK, P., VLCEK, M. Fast analytical design ˇ algorithms for FIR notch filters. IEEE Transactions Circuits and Systems I: Regular Papers, 2004, vol. 51, no. 3, p. 608 - 623.
8. ZAHRADNIK, P., VLCEK, M. An analytical proce- ˇ dure for critical frequency tuning of FIR filters. IEEE Transactions Circuits and Systems II-Express Briefs, 2006, vol. 53, no. 1, p. 72 - 76.
9. VLCEK, M., UNBEHAUEN, R. Zolotarev polynomi- ˇ als and optimal FIR filters. IEEE Transactions on Signal Processing, 1999, vol. 47, no. 3, p. 717 - 730.
10. ABRAMOWITZ, M., STEGUN, I.Handbook of Mathematical Functions. New York (USA): Dover Publications, 1972.

Keywords: Power line, interference suppression, FIR filter, notch filter

J. Nikolic, Z. Peric, L. Velimirovic [references] [full-text] [Download Citations]
Simple Solution for Designing the Piecewise Linear Scalar Companding Quantizer for Gaussian Source

To overcome the difficulties in determining an inverse compressor function for a Gaussian source, which appear in designing the nonlinear optimal companding quantizers and also in the nonlinear optimal companding quantization procedure, in this paper a piecewise linear compressor function based on the first derivate approximation of the optimal compressor function is proposed. We show that the approximations used in determining the piecewise linear compressor function contribute to the simple solution for designing the novel piecewise linear scalar companding quantizer (PLSCQ) for a Gaussian source of unit variance. For the given number of segments, we perform optimization procedure in order to obtain optimal value of the support region threshold which maximizes the signal to quantization noise ratio (SQNR) of the proposed PLSCQ. We study how the SQNR of the considered PLSCQ depends on the number of segments and we show that for the given number of quantization levels, SQNR of the PLSCQ approaches the one of the nonlinear optimal companding quantizer with the increase of the number of segments. The presented features of the proposed PLSCQ indicate that the obtained model should be of high practical significance for quantization of signals having Gaussian probability density function.

1. JAYANT, N., NOLL, P. Digital Coding of Waveforms, Principles and Applications to Speech and Video. New Jersey: Prentice Hall, 1984.
2. MAX., J. Quantizing for minimum distortion. IRE, Trans. Inform Theory, 1960, vol. IT-6, p. 7 - 12.
3. VELIMIROVIĆ, L., PERIĆ, Z., NIKOLIĆ, J. Design of novel piecewise uniform scalar quantizer for Gaussian memoryless source. Radio Science, 2012, vol. 47, RS2005, p. 1 - 6.
4. SANGSIN NA Asymptotic formulas for variance-mismatched fixed-rate scalar quantization of a Gaussian source. IEEE Trans. Signal Processing, 2011, vol. 59, no. 5, p. 2437 - 2441.
5. PERIĆ, Z., NIKOLIĆ, J., MOSIĆ, A., PANIĆ, S. A switchedadaptive quantization technique using μ-law quantizers. Information Technology and Control, 2010, vol. 39, no. 4, p. 317 - 320.
6. PERIĆ, Z., NIKOLIĆ, J., ESKIĆ, Z., KRSTIĆ, S., MARKOVIĆ, N. Design of novel scalar quantizer model for Gaussian source. Information Technology and Control, 2008, vol. 37, no. 4, p. 321 to 325.
7. ITU-T, Recommendation G.711. Pulse Code Modulation (PCM) of Voice Frequencies. 1988.
8. KAZAKOS, D., MAKKI, K. Robust companders. In Proceedings of the 6th WSEAS International Conf. on Telecommunications and Informatics. Dallas (Texas), 2007, p. 32 - 35.
9. NIKOLIĆ, J., PERIĆ, Z., ANTIĆ, D., JOVANOVIĆ, A., DENIĆ, D. Low complex forward adaptive loss compression algorithm and its aplication in speech coding. Journal of Electrical Engineering, 2011, vol. 62, no. 1, p. 19 - 24.
10. VOGEL., P. Analytical coding of Gaussian sources. IEEE Trans. Inform. Theory, 1994, vol. 40, p. 1639 - 1645.
11. SWASZEK, P., THOMAS, B. Multidimensional spherical coordinates quantization. IEEE Trans. Inform. Theory, 1983, vol. IT-29, p. 570 - 576.
12. POPAT, K., ZEGER, K. Robust quantization of memoryless sources using dispersive FIR filters. IEEE Trans. Commun., 1992, vol. 40, no. 11, p. 1670 - 1674.
13. THOMPSON, A., EMERSON, D., SCHWAB, F. Convenient formulas for quantization efficiency. Radio Science, 2007, vol. 42, RS3022, p. 1 - 5.

Keywords: Piecewise linear scalar companding quantizer, support region threshold optimization, compressor function

V. K. Gupta, M. Chandra, S. N. Sharan [references] [full-text] [Download Citations]
Acoustic Echo and Noise Cancellation System for Hand-Free Telecommunication using Variable Step Size Algorithms

In this paper, acoustic echo cancellation with doubletalk detection system is implemented for a hand-free telecommunication system using Matlab. Here adaptive noise canceller with blind source separation (ANC-BSS) system is proposed to remove both background noise and far-end speaker echo signal in presence of double-talk. During the absence of double-talk, far-end speaker echo signal is cancelled by adaptive echo canceller. Both adaptive noise canceller and adaptive echo canceller are implemented using LMS, NLMS, VSLMS and VSNLMS algorithms. The normalized cross-correlation method is used for double-talk detection. VSNLMS has shown its superiority over all other algorithms both for double-talk and in absence of double-talk. During the absence of double-talk it shows its superiority in terms of increment in ERLE and decrement in misalignment. In presence of double-talk, it shows improvement in SNR of near-end speaker signal.

1. SONDHI, M. M. An adaptive echo canceller. Bell Systems Technical Journal, 1967, vol. 46, p. 497 - 510.
2. ÅHGREN, P. Acoustic echo cancellation and doubletalk detection using estimated loudspeaker impulse responses. IEEE Transactions on Speech and Audio Processing, 2005, vol. 13, no. 6, p. 1231 - 1237.
3. HANSLER, E., SCHMIDT, G. Acoustic Echo and Noise Control: A Practical Approach. Hoboken (NJ, USA): Wiley, 2004.
4. CHO, J. H., MORGAN, D. R., BENESTY, J. An objective technique for evaluating doubletalk detectors in acoustic echo cancellers. IEEE Transactions on Speech and Audio Processing, 1999, vol. 7, no. 6, p. 718 - 724.
5. HWANG, S. S., KIM, S. C., LEE, C. D. Real time acoustic echo cancellation technique based on normalized least mean square method. In 2 nd International Conference on Computer Engineering and Technology. Chengdu (China), 2010, vol. 6, p. 12 - 16.
6. SHAO, T., ZHENG, Y. R., BENESTY, J. A variable step-size normalized sign algorithm for acoustic echo cancellation. In IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP). Dallas (TX, USA), 2010, p. 333 - 336.
7. HOMANA, I., TOPA, M. D., KIREI B. S., CONTAN, C. Adaptive algorithms for double-talk echo cancelling. In 9th International Symposium on Electronics and Telecommunications. Timișoara (Romania), 2010, p. 349 - 352.
8. HAYKIN, S. Adaptive Filter Theory, 4th ed. Upper Saddle River (NJ, USA): Prentice Hall, 2002.
9. SAYED, A. H., Fundamentals of Adaptive Filtering. Hoboken (NJ, USA): Wiley, 2003.
10. ABOULNASR, T., MAYYAS, K. A robust variable step size LMS-Type algorithm: Analysis and simulations. In International Conference on Acoustics, Speech, and Signal Processing. Detroit (MI, USA), 1995, vol. 2, p. 1408 - 1411.
11. GREENBERG, J. E. Modified LMS algorithms for speech processing with an adaptive noise canceller. IEEE Transactions on Speech and Audio Processing, 1998, vol. 6, no. 4, p. 338 - 358.
12. WADA, T. S., JUANG, B.-H. H. F. Enhancement of residual echo for robust acoustic echo cancellation. IEEE Transactions on Audio, Speech, and Language Processing, 2012, vol. 20, no.1, p. 175 - 189.
13. MIRARAB, M. R., SOBHANI, M. A, NASIRI, A. A. A new wavelet based blind audio source separation using kurtosis. In 3 rd International Conference on Advanced Computer Theory and Engineering. Chengdu (China), 2010, p. 550 - 553.
14. MOUSSAOUI, R., ROUAT, J., LEFEBVRE, R. Wavelet based independent component analysis for multi-channel source separation. In International Conference on Acoustics, Speech and Signal Processing. Toulouse (France), 2006, vol. 5, p. 645 - 648.
15. HIRAI, N., MATSUMOTO, H., FURUKAWA, T., FURUYA, K. A consideration of blind source separation using wavelet transform. In International Symposium on Intelligent Signal Processing and Communication Systems. 2004, p. 141 - 146.
16. SAMUDRAVIJAYA, K., RAO, P. V. S., AGRAWAL, S. S. Hindi speech database. In Sixth International Conference on Spoken Language Processing (ICSLP). Beijing (China), 2000, CDROM 00192.pdf.
17. VARGA, A., STEENEKEN, H. J. M., JONES, D., The noisex-92 study on the effect of additive noise on automatic speech recognition system, Reports of NATO Research Study Group (RSG.10). 1992.

Keywords: Adaptive filters, double-talk detection, ANC-BSS, ERLE, misalignment, SNR

Min Long, Fei Peng [references] [full-text] [Download Citations]
A Box-Counting Method with Adaptable Box Height for Measuring the Fractal Feature of Images

Most of the existing box-counting methods for measuring fractal features are only applicable to square images or images with each dimension equal to the power of 2 and require that the box at the top of the box stack of each image block is of the same height as that of other boxes in the same stack, which gives rise to inaccurate estimation of fractal dimension. In this paper, we propose a more accurate box-counting method for images of arbitrary size, which allows the height of the box at the top of each grid block to be adaptable to the maximum and minimum gray-scales of that block so as to circumvent the common limitations of existing box-counting methods.

1. MANDELBROT, B. B. The Fractal Geometry of Nature. W.H. Freeman and Company, 1982.
2. PENTLAND, A. P. Fractal-based description of nature scenes. IEEE Transactions on Pattern Analysis and Machine Intelligence, 1984, vol. 6, no. 6, p. 315-326.
3. HUANG, J., TURCOTTE, D. L. Fractal image analysis: application to the topography of Oregon and synthetic images. Journal of Optical Society of America A-Optics Image Science and Vision, 1990, vol. 7, no. 6, p. 1124-1130.
4. GANGEPAIN, J., ROQUES-CARMES, C. Fractal approach to two dimensional and three dimensional surface roughness. Wear, 1986, vol. 109, p. 119-126.
5. CHEN, S. S., KELLER, J. M., CROWNOVER, R. M. On the calculation of fractal features from images. IEEE Transactions on Pattern Analysis and Machine Intelligence, 1993, vol. 15, no. 10, p. 1087-1090.
6. SARKAR, N., CHAUDHURI, B. B. An efficient differential boxcounting approach to compute fractal dimension of image. IEEE Transactions on Systems, Man and Cybernetics, 1994, vol. 24, no. 1, p. 115-120.
7. FENG, J., JIN, W.-C., CHEN, C.-T. Fractional box-counting approach to fractal dimension estimation. In Proceedings of International Conference on Pattern Recognition. 1996, p. 854 - 858.
8. XIE, W., XIE, W. Fractal-based analysis of time series data and features extraction. Signal Processing, 1997, vol. 13, no. 2, p. 98 to 104.
9. BISOI, A. K., MISHRA, J. On calculation of fractal dimension of images. Pattern Recognition Letters, 2001, vol. 22, p. 631-637.
10. LI, J., SUN, C., DU, Q. A new box-counting method for estimation of image fractal dimension. In Proceedings of IEEE International Conference on Image Processing. 2006, p. 3029-3022.
11. XU, S., WENG, Y. A new approach to estimate fractal dimensions of corrosion image. Pattern Recognition Letters, 2006, vol. 27, p. 1942-1947.
12. LI, J., DU, Q., SUN, C. An improved box-counting method for image fractal dimension estimation. Pattern Recognition, 2009, vol. 42, p. 2460-2469.

Keywords: Fractal dimension, image feature, fractal features, box-counting method

A. Dziedzic, D. Nowak [references] [full-text] [Download Citations]
Thick-Film and LTCC Passive Components for High-Temperature Electronics

At this very moment an increasing interest in the field of high-temperature electronics is observed. This is a result of development in the area of wide-band semiconductors’ engineering but this also generates needs for passives with appropriate characteristics. This paper presents fabrication as well as electrical and stability properties of passive components (resistors, capacitors, inductors) made in thick-film or Low-Temperature Co-fired Ceramics (LTCC) technologies fulfilling demands of high-temperature electronics. Passives with standard dimensions usually are prepared by screen-printing whereas combination of standard screen-printing with photolithography or laser shaping are recommenced for fabrication of micropassives. Attainment of proper characteristics versus temperature as well as satisfactory long-term high-temperature stability of micropassives is more difficult than for structures with typical dimensions for thick-film and LTCC technologies because of increase of interfacial processes’ importance. However it is shown that proper selection of thick-film inks together with proper deposition method permit to prepare thick-film micropassives (microresistors, air-cored microinductors and interdigital microcapacitors) suitable for the temperature range between 150°C and 400°C.

1. JOHNSON, R. et al. The changing automotive environment: hightemperature electronics. IEEE Trans. on Electronics Packaging Manufacturing, 2004, vol. 27, p. 164-176.
2. JOHANNESSEN, R. Reliable microelectronics for harsh environment applications – effects of thermal stress and high pressure. PhD thesis, Fac. of Mathematics and Natural Science, Univ. of Oslo, 2008.
3. BUTTAY, C. et al. State of the art of high temperature power electronics. Mat. Sci. and Engn. B, 2011, vol. 176, p. 283-288.
4. NEUDECK, P., OKOJIE, R., CHEN, L.-Y. High-temperature electronics - a role for wide bandgap semiconductors? Proc. of the IEEE, 2002, vol. 90, p. 1065-1076.
5. www.cissoid.com
6. LAHTI, M, LANTTO, V., LEPPAVUORI, S. Planar inductors on an LTCC substrate realized by the gravure-offset printing technique. IEEE Trans. on Comp. and Packaging Technol., 2000, vol. 23, p. 606-610.
7. DZIEDZIC, A. et al. Geometrical and electrical properties of LTCC and thick-film microresistors. Microelectronics Int., Jan 2005, vol. 22, no. 1, p. 26-33.
8. PERRONE, R., THUST, H., DRUE, K.-H. Progress in the integration of planar and 3D coils on LTCC by using photoimageable inks. J. of Microelectronics and Electronic Packaging, 2005, vol. 2, p. 155-161.
9. MIŚ, E. et al. Geometrical, electrical and stability properties of thick-film and LTCC microcapacitors. Microelectronics Int., 2008, vol. 25, no. 2, p. 37-41.
10. MIŚ, E., DZIEDZIC, A., MIELCAREK, W. Microvaristors in thick-film and LTCC circuits. Microelectron. Reliab., 2009, vol. 49, p. 607-613.
11. DZIEDZIC, A., NIJS, J., SZLUFCIK, J. Thick-film fine-line fabrication techniques – application to front metallisation of solar cells. Hybrid Circuits, 1993, no. 30, p. 18-22.
12. DZIEDZIC, A. Modern thick-film and LTCC passives and passive integrated components. Informacije MIDEM, 2009, vol. 39, p. 191 to 200.
13. MINALGIENE, J., BALTRUSAITIS, V. Photoimageable thick film implementation of very high density ceramics technology products. In Proc. 39th IMAPS Nordic Conf.. Stockholm (Sweden), 2002, p. 233-242.
14. DZIEDZIC, A. et al. Fodel microresistors – processing and basic electrical properties. Microelectron. Reliab., 2003, vol. 43, p. 377 to 383.
15. MARKOWSKI, P. Thick-film photoimageable and laser-shaped arms for thermoelectric microgenerators. Microelectronics Int., Sept. 2011, vol. 28, no. 3, p. 43-50.
16. KITA, J. et al. Laser treatment of LTCC for 3D structures and elements fabrication. Microelectron. Int., Sept. 2002, vol. 19, no. 3, p. 14-18.
17. BĄK, M. et al. Chosen electrical and stability properties of lasershaped thick-film and LTCC inductors. In Proc. 2nd Eur. Systemintegration Technology Conf. London (UK), Sept. 2008, p. 101-103.
18. NOWAK, D. et al. Fabrication and electrical properties of lasershaped thick-film and LTCC microresistors. Microelectron. Reliab., 2009, vol. 49, p. 600-606.
19. MIŚ, E. et al. Laser-shaped thick-film and LTCC microresistors. In Proc. 1st Eur. Systemintegration Technology Conf. Dresden (Germany), Sept. 2006, p. 954-960.
20. NOWAK, D. et al. High temperature properties of miniaturized thick-film components. In Proc. 8th IMAPS/ACerS Int. CICMT Conf. Erfurt (Germany), April 2012, p. 400-405.
21. CHIOU, B. S., VEST, R. V. Glasses for high temperature thick film systems. Bull. Am. Ceram. Soc., 1984, vol. 63, p. 816-820.
22. DZIEDZIC, A. Thick film resistors with IrO2 and CaIrx Ti1-xO3 – examples of chemically reactive and unreactive systems. Microelectronics J., Dec 1988, vol. 19, no. 6, p. 24-42.
23. DZIEDZIC, A. Electrical and structural investigations in reliability characterization of modern passives and passive integrated components, Microelectron. Reliab., 2002, vol. 42, p. 709-719.
24. SUTTERLIN, R. C. et al. Thick-film resistor/dielectric interactions in a low temperature co-fired ceramic package. IEEE Trans. on Comp., Hybr., and Manuf. Technol. – B, 1995, vol. 18, p. 346-351.
25. SINNADURAI, N., WILSON, K. The aging behavior of commercial thick-film resistors. IEEE Trans. on Comp., Hybr., and Manuf. Technol., 1982, vol. 5, p. 308-317.
26. MORTEN, B., PRUDENZIATI, M. Thermal ageing of thick-film resistors. Hybrid Circuits, 1983, no. 3, p. 24-26.
27. COLEMAN, M. Ageing mechanisms and stability in thick film resistors. In Proc. 4th EHMC. Copenhagen (Denmark), 1983, p. 20 to 30.
28. DZIEDZIC, A. Electrical properties of DP 1700, R 310 and R 320 resistor series. In Proc. 11th ISHM-Poland Conf., 1988, p. 59-62.
29. BELAVIC, D. et al. Investigation of a possible correlation between current noise and long-term stability of thick-film resistors. In Proc. 1st Eur. Microelectronics and Packaging Symp, Prague (Czech Republic), 2000, p. 464-469.
30. DZIEDZIC, A. Trimming and stability of thick-film resistors with reduced dimensions. In Proc. 25th IMAPS-Poland Conf. Polańczyk (Poland), Sept. 2001, p. 163-166.
31. NAEFE, J. E. et al. High-temperature storage and thermal cycling studies of thick film and wirewound resistors. IEEE Trans. on Comp. and Packag. Technol., 2002, vol. 25, p. 45-52.
32. KUEHL, R. W. Stability of thin film resistors – prediction and differences base on time-dependent Arrhenius law. Microelectron. Reliab., 2009, vol. 49, p. 51-58.
33. DZIEDZIC, A. et al. Electrical and stability properties and ultrasonic microscope characterisation of LTCC resistors. Microelectron. Reliab., 2001, vol. 41, p. 669-676.
34. DZIEDZIC, A. et al. Some remarks about relations between processing conditions and microstructural, electrical as well as stability properties of LTCC resistors. In Proc. 3rd Eur. Microelectronics and Packaging Symp. Prague (Czech Republic), 2004, p. 345-354.
35. DZIEDZIC, A. et al. LTCC resistors and resistive temperature sensors – chosen electrical and stability properties. In Proc. 28th Int. Spring Seminar on Electronics Technology. Wiener Neustadt (Austria), May 2005, p. 165-170.
36. NOWAK, D. et al. High temperature properties of thick-film and LTCC components. Elektronika, Jan 2012, vol. 53, no. 1, p. 35-37.
37. MARKOWSKI, P. et al. Properties of thick-film photoimageable inks for LTCC substrates. Elektronika, March 2011, vol. 53, no. 3, p. 109-111.
38. DE SCHEPPER, L. et al. A new method to test the long-term stability of thick film resistors. Silicates Industries, 1990, vol. 3-4, p. 77-80.
39. DZIEDZIC, A. et al.; Advanced electrical and stability characterization of untrimmed and variously trimmed thick-film and LTCC resistors. Microelectron. Reliab., 2006, vol. 46, p. 352-359.
40. NOWAK, D. et al. Influence of ferrite layer on electrical and stability properties of laser-shaped thick-film and LTCC inductors. In Proc. 32nd Int. Conf. of IMAPS-CPMT Poland 2008. Pułtusk (Poland), Sept. 2008, 5 p.
41. NOWAK, D., DZIEDZIC, A. Some aspects of planar inductors integration. In Proc. 33rd Int. Conf. of IMAPS-CPMT Poland. Pszczyna (Poland), Sept. 2009, p. 277-280.
42. PONCHAK, G. E. et al. Temperature dependence of thin film spiral inductors on alumina over a temperature range of 25 to 475o C. In Proc. 2010 Electronic Components and Technology Conf., p. 713-719.
43. MIŚ, E., DZIEDZIC, A., NITSCH, K. Electrical properties and electrical equivalent models of thick-film and LTCC microcapacitors. Microelectron. Int., May 2009, vol. 26, no. 2, p. 45-50.

Keywords: High-temperature electronics, thick-film technology, LTCC technology, passive component, long-term stability

M. S. Zarnik, D. Belavic, V. Sedlakova, J. Sikula, M. Kopecky, P. Sedlak, J. Majzner [references] [full-text] [Download Citations]
Comparison of the Intrinsic Characteristics of LTCC and Silicon Pressure Sensors by Means of 1/f Noise Measurements

A pressure sensor with high resolution is of key importance for precise measurements in the low-pressure range. The intrinsic resolution of piezoresistive ceramic pressure sensors (CPSs) mainly depends on their func¬tional sensitivity and the electronic noise in the thick-film resistors. Both the sensitivity and the noise level depend on the material and the structural properties, and the dimen¬sions of the sensing structure. In general, the sensitivity can be increased and the noise can be reduced by using additional electronics for the signal processing, but this makes the sensor bigger, more complex and more expen¬sive. In this study we discuss the technological limits for downscaling the sensor’s pressure range without any processing of the sensor’s signal. The intrinsic resolution of the piezoresistive pressure sensors designed for the pressure range 0 to ±100 mbar and realized in LTCC (Low Temperature Cofired Ceramic) technology was evaluated and compared to the resolution of a commercial 100-mbar silicon pressure sensor. Considering their different typical sensitivities, the resolutions of about 0.02 mbar and 0.08 mbar were obtained for the CPS and the silicon sen¬sors, respectively. The low-frequency noise measurements showed that the noise characteristics of both sensors were not influenced by the pressure loads.

1. BELAVIC, D., ZARNIK, M. S., HROVAT, M., MACEK, S., PAVLIN, M., JERLAH, M., HOLC, J., DRNOVSEK, S., CILENSEK, J., KOSEC. M. Benchmarking different types of thick-film pressure sensors. In Proceedings of the IMAPS/ACerS 2007, Int. Conf. CICMT, 2007, p. 278-285.
2. MEADER, T., FAHRNY, V., STAUSS, S., CORRADINI, G., RYSER, P. Design and characterisation of low-cost thick-film piezoresistive force sensors for the 100 mN to 100 N range. In Proc. Int. Conference of IMAPS Poland Chapter. KoszalinDarlowko (Poland), 2005, p.429.
3. ZARNIK, M. S., BELAVIC, D., MACEK, S. The warm-up and offset stability of a low-pressure piezoresistive ceramic pressure sensor. Sensors and Actuators A, 2010, vol. 158, no. 2, p. 198-206.
4. SEDLAKOVA, V., MAJZNER, J., SEDLAK, P., KOPECKY, M., SIKULA, J., ZARNIK, M. S., BELAVIC, D., HROVAT, M. Evaluation of piezoresistive ceramic pressure sensors using noise measurements. Informacije MIDEM, 2012, vol. 42, no.2, p. 109- 114.
5. ROCAK, D., BELAVIC, D., HROVAT, M., SIKULA, J., KOKTAVY, P., PAVELKA, J., SEDLAKOVA, V. Low frequency noise of thick film resistors as quality and reliability indicator. Microelectronics Reliability, 2002, vol. 41, no. 4, p. 531-542.
6. VIDYBIDA, A. K. Adsorption–desorption noise can be used for improving selectivity. Sensor Actuator A, 2003, vol. 107, p. 233- 237.
7. SMULKO, J. Electrochemical noise analysis methods for the investigation of corrosion processes. In Proc. SPIE, Noise and Information in Nanoelectronics, Sensors and Standards. Santa Fe (USA), 2-4 June 2003, vol. 5115, p. 86–91.
8. GOMRI, S., SEGUIN, J., GUERIN, J., AGUIR, K. Adsorption– desorption noise in gas sensors: Modelling using Langmuir and Wolkenstein models for adsorption. Sensors & Actuators B, 2006, vol. 114, p. 451–459.
9. HASSE, L., KOTARSKI, M., SMULKO, J., MAJZNER, J., SEDLAKOVA, V., SEDLAK, P., SIKULA, J. Comparison of effectiveness of gas sensing by low frequency fluctuations in resistance and microbalance quartz gas sensors. In Proc. of 21st International Conference on Noise and Fluctuations (ICNF 2011). Toronto (Canada), June 12-16, 2011, p. 266-269.
10. SEDLAK, P., SIKULA, J., MAJZNER, J., VRNATA, M., FITL, P., KOPECKY, D., VYSLOUZIL, F., HANDEL, P. H. Adsorption–desorption noise in QCM gas sensors. Sensors and Actuators B-Chemical, 2012, vol. 166, p. 264-268.
11. SIKULA, J., SEDLAKOVA, V., TACANO, M., ZEDNICEK, T. Reliability of electronic devices: Failure mechanisms and testing. Reliability, Risk and Safety: Theory and Applications, 2011, vol. 1-3, p. 1925-1936.
12. ZARNIK, M. S., BELAVIC, D. Stability of a piezoresistive ceramic pressure sensor made with LTCC technology. In Proc. IMAPS/ACerS Conf, CICMT 2012.
13. HROVAT, M., BELAVIC, D., SAMARDZIJA, Z., HOLC, J. A characterisation of thick film resistors for strain gauge applications. Journal of Materials Science, 2001, vol. 36, no. 11, p. 2679-2689.
14. BAE, B., FLACHSBART, B. R., PARK, K., SHANNON, M. A. Design optimization of a piezoresistive pressure sensor considering the output signal-to noise ratio. J. Micromech Microeng, 2004, vol. 14, p. 1597-1607.

Keywords: LTCC pressure sensor, intrinsic resolution, noise spectral density

V. Prajzler, H. Tuma, J. Spirkova, V. Jerabek [references] [full-text] [Download Citations]
Design and Modeling of Symmetric Three Branch Polymer Planar Optical Power Dividers

Two types of polymer-based three-branch symmetric planar optical power dividers (splitters) were designed, multimode interference (MMI) splitter and triangular shape-spacing splitter. By means of modeling the real structures were simulated as made of Epoxy Novolak Resin on silicon substrate, with silica buffer layer and polymethylmethacrylate as protection cover layer. The design of polymer waveguide structure was done by Beam Propagation Method. After comparing properties of both types of the splitters we have demonstrated that our new polymer based triangular shaped splitter can work simultaneously in broader spectrum, the only condition would be that the waveguides are single-mode guiding. It practically means that, what concerns communication wavelengths, it can on principle simultaneously operate at two mainly used wavelengths, 1310 and 1550 nm.

1. YABU, T., GESHIRO, M., MINAMI, N., SAWA, S. Symmetric three-branch optical power divider with a coupling gap. Journal of Lightwave Technology, 1999, vol. 17, no. 9, p. 1693-1699.
2. HUANG, C.C., CHANG, C.Y., WANG, W.S. Single-mode fourbranch power divider with coupled wide-angle waveguides. Microwave and Optical Technology Letters, 2003, vol. 38, no. 4, p. 337-341.
3. BANBA, S., OGAWA, H. Novel symmetrical three-branch optical waveguide with equal power division. IEEE Microwave and Guided Wave Letters, 1992, vol. 2, no. 5, p. 188-190.
4. SOLDANO, L. B., PENNINGS, E. C. M. Optical multi-mode interference devices based on self-imaging - principles and applications. Journal of Lightwave Technology, 1995, vol. 13, no. 4, p. 615–627.
5. BESLEY, J. A., LOVE, J. D., LANGER, W. A multimode planar power splitter. Journal of Lightwave Technology, 1998, vol. 16, no. 4, p. 678-684.
6. HARUNA, M., BELANGER, M., YIP, G. L. Passive 3-branch optical power divider by K+ -ion exchange in glass. Electronics Letters, 1985, vol. 21, no. 12, p. 535-536.
7. WANG, T.J., HUANG, C.F., WANG, W.S. Wide-angle 1x3 optical power divider in LiNbO3 for variable power splitting. IEEE Photonics Technology Letters, 2003, vol. 15, no. 10, p. 1401- 1403.
8. MIN, D.S., LANGER, D. W., PANT, D. K., COALSON, R. D. Wide-angle low loss waveguide branching for integrated optics. Integrated Optics, 1997, vol. 16, no. 4, p. 331-342.
9. SAKAI, A., FUKAZAWA, T., TOSHIHIKO, B. Low loss ultra small branches in silicon photonics wire waveguide. IEICE Trans. Electron., 2002, vol. E85-C, no. 4, p. 1033-1038.
10. GAO, Y., GONG, Z., BAI, R., HAO, Y.L., LI, X.H., JIANG, X.Q., WANG, M.H., PAN, J.X., YANG, J.Y. Multimode-waveguidebased optical power splitters in glass. Chinese Physics Letters, 2008, vol. 25, no. 8, p. 2912-2914.
11. HEATON, J. M., JENKINS, R. M., WIGHT, D. R., PARKER, J. T., BIRBECK, J. C. H., HILTON, K. P. Novel 1-to-N way integrated optical beam splitters using symmetric mode mixing in GaAs/AlGaAs multimode waveguides. Applied Physics Letters, 1992, vol. 61, no 15, p. 1754 – 1756.
12. WANG, F., YANG, J.Y., CHEN, L.M., JIANG, X., WANG, M. Optical switch based on multimode interference coupler. IEEE Photonics Technology Letters, 2006, vol. 18, no. 1-4, p. 421-423.
13. JINGTAO, Z., HUIHUI, Z., XINYU, LIU Design and fabrication of a compact multimode interference splitter with silicon photonic nanowires. Chinese Optics Letters, 2009, vol. 7, no. 11, p. 1041 to 1044.
14. BLAHUT, M., FRONIEWSKI, D. Self-imaging effects in curved gradient index multimode interference structures made by K+ -Na+ ion exchange. Optica Applicata, 2009, vol. 39, no. 3, p. 445-458.
15. ELDADA, L., SHACKLETTE, L. W. Advances in polymer integrated optics. IEEE Journal of Selected Topics in Quantum Electronics, 2000, vol. 6, no. 1, p. 54-68.
16. MA, H., JEN, A.K.Y., DALTON, L. R. Polymer-based optical waveguides: Materials, processing, and devices. Advanced Materials, 2002, vol. 14, p. 1339-1365.
17. RABIEI, P., STEIER, W. H., ZHANG, C., DALTON, L. R. Polymer micro-ring filters and modulators. IEEE Journal of Lightwave Technology, 2002, vol. 20, p. 1968–1975.
18. WONG, W.H., LIU, K.K. CHAN, K.S., PUN, E.Y.B. Polymer devices for photonics applications. Journal of Crystal Growth, 2006, vol. 288, no. 1, p. 100-104.
19. BECHE, B., PELLETIER, N., GAVIOT, E., ZYSS, J. Single-mode TE00-TM00 optical waveguides on SU-8 polymer. Optics Communications, 2004, vol. 230, no. 1-3, p. 91-94.
20. TUNG, K.K., WONG, W.H., PUN, E.Y.B. Polymeric optical waveguides using direct ultraviolet photolithography process. Applied Physics A Materials Science & Processing, 2005, vol. 80, p. 621–626.
21. PRAJZLER, V., LYUTAKOV, O., HUTTEL, I., BARNA, J., SPIRKOVA, J., NEKVINDOVA, P., JERABEK, V. Simple way of fabrication of epoxy novolak resin optical waveguides on silicon substrate. Physica Status Solidi C, 2011, vol. 1–4. DOI 10.1002/pssc.201084031.
22. MUKHERJEE, B. Optical WDM Networks. Springer, 2006.
23. POLLOCK, C. R. Fundamentals of Optoelectronics. Richard D Irwin, 1994.
24. RSoft Design Group, User Guide BeamPROP www.rsoftdesign.com.
25. SHI, Y., DAI, D. Design of a compact multimode interference coupler based on deeply-etched SiO2 ridge waveguides. Optics Communications, 2007, vol. 271, no. 2, p. 404–407.
26. IBRAHIM, M. H., SHUH-YING, L., MEE-KOY, C., KASSIM, N. M., MOHAMMAD, A. B. Multimode interference optical splitter based on photodefinable benzocyclobutene, (BCB 4024-40) polymer. Optical Engineering, 2007, vol. 46, no. 1, p. 013401-1- 013401-4.
27. JENKINS, R. M., DEVERAUX, R. W. J., HEATON, J. M. Waveguide beam splitters and recombiners based on multimode propagation phenomena. Optics Letters, 1992, vol. 17, no. 14, p. 991-993.

Keywords: Optical waveguides, optical dividers, three-branch, design, polymer

J. Racko, J. Pechacek, M. Mikolasek, P. Benko, A. Grmanova, L. Harmatha, J. Breza [references] [full-text] [Download Citations]
Trap-Assisted Tunneling in the Schottky Barrier

The paper presents a new way how to calculate the currents in a Schottky barrier. The novel phenomeno-logical model extends the Shockley-Read-Hall recombi-nation-generation theory of trap-assisted tunneling. The proposed approach explains the occurrence of large leakage currents in Schottky structures on wide band semi-conductors with a high Schottky barrier (above 1 eV) and with a high density of traps. Under certain conditions, trap-assisted tunneling (TAT) plays a more important role than direct tunneling.

1. MIMOUNI, A., FERNANDEZ, T., RODRIGUEZ-TELLEZ, J., TAZON, A., BAUDRAND, H., BOUSSUIS, M. Gate leakage current in GaN HEMT’s: A degradation modeling approach. Electrical and Electronic Engineering, 2012, vol. 2, no. 6, p. 397 - 402.
2. YAMADA, T., TSUCHIYA, T., IMADA, K., IWAMI, M., KIKAWA, J., ARAKI, T., SUZUKI, A, NANISHI, Y. Gate leakage currents of AlGaN/GaN HEMT structures grown by metalorganic vapour phase epitaxy. Physica Status Solidi (c), 2007, vol. 4, no. 7, p. 2690 - 2694.
3. HOUSSA, M., TUOMINEN, M., NAILI, M., AFANAS’EV, V., STESMANS, A., HAUKKA, S., HEYNS, M. M. Trap-assisted tunneling in high permittivity gate dielectric stacks. Journal of Applied Physics, 2000, vol. 87, no. 12, p. 8615 - 8620.
4. RACKO, J., MIKOLASEK, M., GRANZNER, R., BREZA, J., DONOVAL, D., GRMANOVA, A., HARMATHA, L., SCHWIERZ, F., FROHLICH, K. Trap-assisted tunneling current in MIM structures. Central European Journal of Physics, 2011, vol. 9, no. 1, p. 230 - 241.
5. RACKO, J., MIKOLASEK, M., HARMATHA, L., BREZA, J., HUDEC, B., FROHLICH, K., AARIK, J., TARRE, A., GRANZNER, R., SCHWIERZ, F. Analysis of leakage current mechanisms in RuO2-TiO2-RuO2 MIM structures. Journal of Vacuum Science and Technology B, 2011, vol. 29, no. 1, p. 01AC08-1 - 01AC08-8.
6. SCHENK, A. A model for the field and temperature dependence of Shockley-Read-Hall lifetimes in silicon. Solid-State Electronics, 1992, vol. 35, no. 11, p. 1585 - 1596.
7. RACKO, J., MIKOLASEK, M., GRMANOVA, A., BREZA, J., BENKO, P., GALLO, O., HARMATHA, L. A new model of multiphonon excitation trap-assisted band-to-band tunneling. Radioengineering, 2012, vol. 21, no. 1, p. 213 - 218.
8. RACKO, J., MIKOLASEK, M., GRANZNER, R., AL MUSTAFA, N., SCHWIERZ, F., BREZA, J. The impact of changed barrier layer parameters upon tunnelling in GaN/AlGaN/GaN Schottky structures. In Proceedings of the 9th International Conference on Advanced Electron Devices and Microsystems ASDAM 2012. Smolenice (Slovakia), 2012, p. 207 - 210.

Keywords: Trap-assisted, direct tunneling, Schottky barrier

J. Formanek, J. Jakovenko [references] [full-text] [Download Citations]
Thermal Characterization and Lifetime Prediction of LED Boards for SSL Lamp

This work presents a detailed 3-D thermo-mechanical modelling of two LED board technologies to compare their performance. LED board are considered to be used in high power 800 lumen retrofit SSL (Solid State Lighting) lamp. Thermal, mechanical and life time properties are evaluated by numerical modelling. Experimental results measured on fabricated LED board samples are compared to calculated data. Main role of LED board in SSL lamp is to transport heat from LED die to a heat sink and keep the thermal stresses in all layers as low as possible. The work focuses on improving of new LED board thermal management. Moreover, reliability and lifetime of LED board has been inspected by numerical calculation and validated by experiment. Thermally induced stress has been studied for wide temperature range that can affect the LED boards (-40 to +125°C). Numerical modelling of thermal performance, thermal stress distribution and lifetime has been carried out with ANSYS structural analysis where temperature dependent stress-strain material properties have been taken into account. The objective of this study is to improve not only the thermal performance of new LED board, but also identification of potential problems from mechanical fatigue point of view. Accelerated lifetime testing (e.g., mechanical) is carried out in order to study the failure behaviour of current and newly developed LED board.

1. YOSHIHIKO, K., YOSHIHARU, K. Evaluation of creep properties for Sn–Ag–Cu micro solder joint. Microelectronics Reliability, 2012, vol. 52, p. 1435 - 1440.
2. PIMPUTKAR, S., et al. Prospects for LED lighting. Nature Photonics, Apr. 2009, vol. 3, p. 179-181.
3. JAKOVENKO, J., FORMANEK, J., JANICEK, V., HUSAK, M., WERKHOVEN, R. High power solid state retrofit lamp thermal characterization and modeling. Radioengineering, 2012, vol. 21, no. 1, p. 231 – 238.
4. ASM International group. Atlas of Stress-Strain Curves. ASM International, 2011, ISBN-13: 978-0871707390.
5. FIEDLER, B., HOBBIEBRUNKEN, T., HOJO, M., SCHULTE, K. Influence of stress state and temperature on the strength of epoxy resins. In Proceedings of ICF2011, 2011.
6. HONG, B.-Y., YUAN, T. Integrated flow-thermo-mechanical and reliability analysis of a low air cooled flip chip PBGA package. In 48th Electronic Components Technical Conf.. Seattle (USA), 1998.
7. DUDEK, R., PUFALL, R., SEILER, B., MICHEL, B. Studies on the reliability of power packages based on strength and fracture criteria. Microelectron. Reliab., 2012, vol. 52, p. 1255 to 1265.
8. IPC-Association. Connecting Electronics Industries, Bannockburn. Performance Tests Methods and Qualification Requirements for Surface Mount Solder Attachments, IPC-9701A. 2006.
9. PASCOE, N. Reliability Technology: Principles and Practice of Failure Prevention in Electronic Systems. John Wiley & Sons 2011. ISBN13: 333-0000360726.
10. CAMPBELL, F. Elements of Metallurgy and Engineering Alloys. ASM International, 2008. ISBN-13: 978-0871708670.
11. STAM, F.-A., DAVITT, E. Effects of thermomechanical cycling on lead and lead-free (SnPb and SnAgCu) surface mount solder joints. Microelectronics Reliability, 2001, p. 1815 - 1822.
12. VANDEVELDE, B., DEGRYSE, D., BEYNE, E., ROOSE, E., CORLATAN, D., SWAELEN, G., et al. Modified micro-macro thermo-mechanical modeling of ceramic ball grid array packages. Microelectronics Reliability, 2003, vol. 43, p. 307 - 318.
13. SCHUBERT, E., et al. Solid-state lighting: a benevolent technology. Reports on Progress in Physics, 2006, vol. 69, p. 3069 -3099.
14. HUMPHREYS, C.-J. Solid-state lighting. Mrs Bulletin, 2008, vol. 33, p. 459 - 470.
15. MARONGIU, M.-J. Thermal management of high-power LED systems. LED Professional Review, 2009, no. 13, p. 47 – 50. ISSN 1993-890X.
16. KIM, H.-H., CHOI, S.-H., SHIN, S.-H., LEE, Y.-K., CHOI, S.-M., YI, S. Thermal transient characteristics of die attach in high power LED packages. Microelectronics Reliability, 2008, vol. 48, p. 445 to 454.
17. YOON, J.-W., CHUN, H.-S., JUNG, S.-B. Reliability analysis of Au–Sn flip-chip solder bump fabricated by co-electroplating. Journal of Materials Research, 2007, vol. 22, no. 5, p. 1219-1229.

Keywords: Solid state lightning, thermo-mechanical modelling, lifetime, reliability, LED board

V. Janicek, M. Husak [references] [full-text] [Download Citations]
3D Energy Harvester Evaluation

This paper discusses the characterization and evaluation of an MEMS based electrostatic generator, a part of the power supply unit of the self-powered microsystem[1,2,3]. The designed generator is based on electrostatic converter and uses the principle of conversion of non-electric energy into electrical energy by periodical modification of gap between electrodes of a capacitor [4]. The structure is designed and modeled as three-dimensional silicon based MEMS. Innovative approach involving the achievement of very low resonant frequency of the structure (about 100Hz) by usage of modified long cantilever spring design, minimum area of the chip, 3D work mode, the ability to be tuned to reach desired parameters, proves promising directions of possible further development.

1. JANICEK, V., HUSAK, M. Self-powered microsystems with PVDF based microgenerator. In IMAPS 2007 Proceedings. Washington (USA), 2007. p. 953 - 957.
2. JANICEK, V., HUSAK, M., JAKOVENKO, J., FORMANEK, J. Design and fabrication of 3D electrostatic energy harvester. Radioengineering, 2012, vol. 21, no. 1, p. 231 - 238.
3. FRY, D. N., HOLCOMB, D. E., MUNRO, J. K., OAKES, L. C., MASTON, M. J. Compact Portable Electric Power Sources (report ORNL/TM-13360). Oak Ridge (USA): Oak Ridge National Laboratory, 1997.
4. BEEBY, S. P., TUDOR, M. J., WHITE, N. M. Energy harvesting vibration sources for microsystems applications. Journal of Measurement Science and Technology, 2006, vol. 17, no. 12, p. 175 - 195.
5. MARZENCKI, M., BASROUR, S., CHARLOT, B., GRASSO, A., COLIN, M., VALBIN, L. Design and fabrication of piezoelectric micro power generators for autonomous microsystems. In Proceedings of Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS DTIP05. Montreux (Switzerland), 2005, p. 299 - 302.
6. STERKEN, T., FIORINI, P., BAERT, K., BORGHS, G., PUERS, R. Novel design and fabrication of a MEMS electrostatic vibration scavenger. In Power MEMS Conference. Kyoto (Japan), 2004, p. 18 - 21.
7. ROUNDY, S., WRIGHT, P., PISTER, K. Microelectrostatic vibration-to-electricity converters. In Proceedings of ASME International Mechanical Engineering Congress & Exposition (IMECE). New Orleans (USA), 2002, p. 1 - 10.
8. ROUNDY, S. Energy Scavenging for Wireless Sensor Nodes with a Focus on Vibration to Electricity Conversion. Ph.D. Dissertation. Berkeley (USA): University of California, 2003.
9. SODANO, H., INMAN, D., PARK, G. A review of power harvesting from vibration using piezoelectric materials. The Shock and Vibration Digest, 2004, vol. 36. p. 197 - 205.

Keywords: MEMS, generator, characterization, energy, evaluation

K. Gupta, N. Pandey, M. Gupta [references] [full-text] [Download Citations]
Low-Voltage MOS Current Mode Logic Multiplexer

In this paper, a new low-voltage MOS current mode logic (MCML) multiplexer based on the triple-tail cell concept is proposed. An analytical model for static parameters is formulated and is applied to develop a design approach for the proposed low-voltage MCML multiplexer. The delay of the proposed low-voltage MCML multiplexer is expressed in terms of the bias current and the voltage swing so that it can be traded off with the power consumption. The proposed low-voltage MCML multiplexer is analyzed for the three design cases namely high-speed, power-efficient, and low-power. Finally, a comparison in performance of the proposed low-voltage MCML multiplexer with the traditional MCML multiplexer is carried out for all the cases.

1. JANTZI, S., MARTIN, K., SEDRA, A. Quadrature bandpass ΣΔ modulator for digital radio. IEEE Journal of Solid-State Circuits, 1997, vol. 32, no. 12, p. 1935 - 1949.
2. LUSCHAS, S., SCHREIER, R., LEE, H. S. Radio frequency digital-to-analog converter. IEEE Journal of Solid-State Circuits, 2004, vol. 39, no. 9, p. 1462 - 1467.
3. KUP, B., DIJKMANS, E., NAUS, P., SNEEP, J. A bit-stream digital-to-analog converter with 18-b resolution. IEEE Journal of Solid-State Circuits, 1991, vol. 26, no. 12, p. 1757 - 1763.
4. TAKAAMOTO, T., HARAJIRI, S., SAWADA, M., KOBAYASHI, O., GOTOH, K. A bonded–SOI-wafer CMOS 16-bit 50- KSPS delta-sigma ADC. In Proceedings of IEEE Custom Integrated Circuit Conference. San Diego (CA, USA), 1991, p. 18.1.1–18.1.4.
5. WESTE, N., ESHRAGHIAN, K., Principles of CMOS VLSI Design: A System Perspective. Boston (USA): Addison-Wesley, 1993.
6. ALLSTOT, D., CHEE, S., KIAEI, S., SHRISTAWA, M. Folded source-coupled logic vs. CMOS static logic for low-noise mixedsignal ICs. IEEE Transactions on Circuits and Systems – I, 1993, vol. 40, no. 9, p. 553 - 563.
7. CHOY, C., CHAN, C., KU, M., POVAZANEC, J. Design procedure of low noise high-speed adaptive output drivers. In Proceedings of the IEEE International Symposium on Circuits and Systems. Hong Kong (China), 1997, p. 1796 - 1799.
8. KIAEI, S., ALLSTOT, D. Low-noise logic for mixed-mode VLSI circuits. Microelectronics Journal, 1992; vol. 23, no. 2, p. 103 - 114.
9. SAEZ, R., KAYAL, M., DECLERQ, M., SCHNEIDER, M. Digital circuit techniques for mixed analog/digital circuits applications. In Proceedings of 3rd International Conference on Electronics, Circuits, and Systems. Rodos (Greece), 1996, p. 956 -959.
10. NG, H., ALLSTOT, D. CMOS current steering logic for lowvoltage mixed-signal integrated circuits. IEEE Transactions on VLSI Systems, 1997, vol. 5, no. 3, p. 301 - 308.
11. KUNDAN, J., HASAN, S. Enhanced folded source-coupled logic technique for low-voltage mixed-signal integrated circuits. IEEE Transactions on Circuits and Systems – II, 2000, vol. 47, no. 8, p. 810 - 817.
12. YAMASHINA, M., YAMADA, H. An MOS current code logic (MCML) circuit for low power sub-GHz processors. IEICE Transactions on Electronics, 1992, vol. E75-C, no. 10, p. 1181 -1187.
13. BRUMA, S. Impact of on-chip process variations on MCML performance. In Proceedings of IEEE Conference on Systems-onChip. Portland (OR, USA), 2003, p. 135 - 140.
14. MUSICER, J. M., RABAEY, J. MOS current mode logic for low power, low noise, CORDIC computation in mixed-signal environments. In Proceedings of the International Symposium of Low Power Electronics and Design. Rapallo (Italy), 2000, p. 102 - 107.
15. MIZUNO, M., YAMASHINA, M., FURUTA, K., IGURA, H., ABIKO, H., OKABE, K., ONO, A., YAMADA, H. A GHz MOS adaptive pipeline technique using MOS current mode logic. IEEE Journal of Solid-State Circuits, 1996, vol. 31, no. 6, p. 784 - 791.
16. GREEN, M. M., SINGH, U. Design of CMOS CML circuits for high speed broadband communications. In Proceedings of the International Symposium on Circuits and Systems. Bangkok (Thailand), 2003, vol. 2, p. 204 - 207.
17. SHIN, J. K.; YOO, T. W., LEE M. Design of half-rate linear phase detector using MOS current mode logic gates for 10-Gb/s clock and data recovery circuit. In Proceedings of IEEE International Conference on Advanced Communication Technology. Phoenix Park (Korea), 2005, p. 205 - 210.
18. YOUNGKYUN, J., SUNGYOUNG, J., JIN, L. A. A CMOS impulse generator for UWB wireless communication systems. In Proceedings of the International Symposium on Circuits and Systems. Vancouver (Canada), 2004, p. 129 - 132.
19. TANABE, A., UMETANI, M., FUJIWARA, I., OGURA, T., KATAOKA, K., OKIARA, M., SAKURABE, H., ENDOH, T., MASUKA, F. 0.18 μm CMOS 10-Gb/s multiplexer/demultiplexer ICs using current mode logic with tolerance to threshold voltage fluctuation. IEEE Journal of Solid-State Circuits, 2001, vol. 36, no. 6, p. 988 - 996.
20. ALIOTO, M., MITA, R., PALUMBO, G. Design of high-speed power efficient MOS current mode logic frequency dividers. IEEE Transactions on Circuits and Systems – II: Express Briefs; 2006, vol. 53, no. 11, p. 1165 - 1169.
21. YAUN, F. CMOS Current-mode Circuits for Data Communication. New York (USA): Springer, 2007.
22. ALIOTO, M., PALUMBO, G. Model and Design of Bipolar and MOS Current-Mode logic: CML, ECL and SCL Digital Circuits. Dordrecht (The Netherlands): Springer, 2005.
23. KIMURA, K. Circuit design techniques for very low-voltage analog functional blocks using triple-tail cells. IEEE Transactions on Circuits and Systems – I: Fundamental Theory and Applications, 1995, vol. 42, p. 873 - 885.
24. MATSUMOTO, F., NOGUCHI, Y. Linear bipolar OTAs based on a triple-tail cell employing exponential circuits. IEEE Transactions on Circuits and Systems – II: Express Briefs, 2004, vol. 51, no. 12, p. 670 - 674.
25. ALIOTO, M., MITA, R., PALUMBO, G. Performance evaluation of the low-voltage CML D-latch topology. Integration, the VLSI Journal, 2003, vol. 36, no. 4, p. 191 - 209.
26. KIMURA, K. Analog Multiplier Using Multi Tail Cell. United States Patent no. 5,986,494, 1999.
27. KIMURA, K., Transconductance-Variable Analog Multiplier using Triple - Tail Cells. United states Patent no. 5,617,052, 1997.
28. ALIOTO, M., PALUMBO, G. Power-delay optimization of Dlatch/MUX source coupled logic gates. International Journal of Circuit Theory and Applications, 2005, vol. 33, n. 1, p. 65 - 85.
29. HASSAN, H., ANIS, M., ELMASRY, M. Analysis and design of low-power multi-threshold MCML. In Proceedings of the IEEE International Conference on System-on-chip. 2004, p. 25 - 29.
30. ALIOTO, M., PALUMBO, G., PENNISI, S. Modeling of sourcecoupled logic gates. International Journal of Circuit Theory and Applications, 2002, vol. 30, no. 4, p. 459 - 477.
31. HASSAN, H., ANIS, M., ELMASRY, M. MOS current mode circuits: analysis, design, and variability. IEEE Transactions on Very Large Scale Integration (VLSI) Systems, 2005, vol. 13, no. 8, p. 885 - 898.
32. RABAEY, J. Digital Integrated Circuits (A Design Perspective), 2nd ed. Englewood Cliffs (NJ, USA): Prentice Hall, 2003.

Keywords: MOS current mode logic, low-voltage, triple-tail cell

Kang-Chun Peng, Chiu-Chin Lin, Ching-Hui Chao [references] [full-text] [Download Citations]
A Novel Three-Point Modulation Technique for Fractional-N Frequency Synthesizer Applications

This paper presents a novel three-point modulation technique for fractional-N frequency synthesizer applications. Convention modulated fractional-N frequency synthesizers suffer from quantization noise, which degrades not only the phase noise performance but also the modulation quality. To solve this problem, this work proposes a three-point modulation technique, which not only cancels the quantization noise, but also markedly boosts the channel switching speed. Measurements reveal that the implemented 2.4 GHz fractional-N frequency synthesizer using three-point modulation can achieve a 2.5 Mbps GFSK data rate with an FSK error rate of only 1.4 %. The phase noise is approximately -98 dBc/Hz at a frequency offset of 100 kHz. The channel switching time is only 1.1 μs with a frequency step of 80 MHz. Comparing with conventional two-point modulation, the proposed three-point modulation greatly improves the FSK error rate, phase noise and channel switching time by about 10 %, 30 dB and 126 μs, respectively.

1. WU, J. M., YEH, C. H., CHUANG, C. J. High dynamic range RF front end with noise cancellation and linearization for WiMAX receivers. Radioengineering, 2012, vol. 21, no. 2, p. 704 – 711.
2. BAUDOIN, G., VILLEGAS, M., SUAREZ, M., DIET, A., ROBERT, F. Performance analysis of multiradio transmitter with polar or cartesian architectures associated with high efficiency switched-mode power amplifiers. Radioengineering, 2010, vol. 19, no. 4, p. 470-478.
3. SU, P. U., HSU, C. M. A 0.25 um CMOS OPLL transmitter IC for GSM and DCS. In Digest of the 2004 IEEE Radio Frequency Integrated Circuits Symposium. 2004, p. 435-438.
4. Silicon Laboratories Inc. Austin. TX. SI4210 Aero II GSM/GPRS Transceiver (datasheet). 2 pages. [Online] Cited 2012-010-29. Available at: http://www.futurel.bg/datasheets/2/AeroII_PB.pdf.
5. CAMINO, L., RAMET, S., BEGUERET, J. B., DEVAL, Y., FOUILLAT, P. Phase error determination in GMSK modulated fractional-N PLL. In Digest of the 8th IEEE International Conference on Electronics, Circuits and Systems, 2001, p. 47-50.
6. WILKINS, B. Polaris total RadioTM, a highly integrated RF solution for GSM /GPRS and EDGE. In Digest of the 2003 IEEE Radio Frequency Integrated Circuits Symposium. 2003, p. 383-386.
7. PENG, K. C., HUANG, C. H., PAN, C. N., HORNG, T. S. High performance frequency hopping transmitters using two-point deltasigma modulation. In Digest of the 2004 IEEE MTT-S International Microwave Symposium, 2004, p. 2011-2014.
8. PENG, K. C., HUANG, C. H., LI, C. J., HORNG, T. S. High performance frequency hopping transmitters using two-point deltasigma modulation. IEEE Transaction on Microwave Theory and Techniques, 2004, vol. 52, no. 11, p. 2529-2535.
9. PENG, K. C., HUANG, C. H., LI, C. J., HORNG, T. S., LEE, S. F. Design of a CMOS VCO with two tuning inputs applied for a wideband GFSK-modulated frequency synthesizer. In Digest of the 2006 IEEE Radio and Wireless Symposium, 2006, p. 443-446.
10. LI, C. J., HUANG, C. H., HO, W. H., HORNG, T. S., PENG, K. C. Incorporating the single-loop delta-sigma modulator in fractional-N frequency synthesizer for phase-noise improvement. In Proceedings of the 1st European Microwave Integrated Circuits Conference, 2006, p. 183-186.
11. PENG, K. C., WU, P. S. High performance fractional–N frequency synthesizer using a two-point channel selection technique. In Digest of the 2009 IEEE Asia-Pacific Microwave Conference, 2009, p. 1275-1278.
12. CHRISTOFFERS, N., KOKOZINSKI, R., KOLNSBERG, S., HOSTICKA, B. J. High loop-filter-order sigma-delta fractional-N frequency synthesizers for use in frequency-hopping-spread-spectrum communication-systems. In Proceeding of the 2003 IEEE International Symposium on Circuits and Systems, 2003, p. 216 to 219.
13. SHU, K., SANCHEZ-SINENCIO, E., MALOBERTI, F., EDURI, U. A comparative study of digital ΣΔ modulators for fractional-N synthesis. In Digest of the 8th IEEE International Conference on Electronics, Circuits and Systems, 2001, p. 1391-1394.
14. VAGNER, P., KUTIN, P. X-band PLL synthesizer. Radioengineering, 2006, vol. 15, no. 1, p. 13 – 16.
15. DENT, P. W. Frequency synthesizer systems and methods for three-point modulation with a DC response. United States Patent No. 5834987, 1998.

Keywords: Fractional-N frequency synthesizer, delta-sigma, three-point modulation, phase-locked loop, GFSK

F. G. Zhu, S. Gao [references] [full-text] [Download Citations]
Compact Elliptically Tapered Slot Antenna with Non-uniform Corrugations for Ultra-wideband Applications

A small size elliptically tapered slot antenna (ETSA) fed by coplanar waveguide (CPW) for ultra-wideband (UWB) applications is proposed. It is printed on an FR4 substrate and occupies a size of 37×34×0.8 mm³. A pair of quarter circular shapes is etched on the radiator to reduce the size. To overcome the limitation of uniform corrugation, non-uniform corrugation is utilized to reduce the cross-polarization level. A parametric study is carried out to investigate the effects of circular cut and corrugations. In order to validate the design, a prototype is fabricated and measured. Both simulated and measured results confirm that the proposed antenna achieves a good performance of a reflection coefficient below -10 dB from 3.1 GHz to 10.6 GHz, including a maximum antenna gain of 8.1dBi, directional patterns in the end-fire direction, low cross-polarization level below -20 dB and linear phase response. The antenna is promising for applications in UWB impulse radar imaging.

1. ALLEN, B., DOHLER, M., OKON, E. E., MALIK, W. Q., BROWN, A. K., EDWARDS, D. J. Ultra-wideband Antennas and Propagation for Communications, Radar and Imaging. New York: Wiley, 2007, ch. 1, p. 1-5.
2. ABBOSH, A. M. Directive antenna for ultra-wideband medical imaging systems. International Journal of Antennas and Propagation, 2008.
3. YANG, Y., FATHY, A. E, Development and implementation of a real-time see-through-wall radar system based on FPGA. IEEE Transactions on Geosciences and Remote Sensing, 2009, vol. 47, no. 5, p. 1270-1280.
4. ZHANG, F., ZHANG, F. S., ZHAO, G., LIN, C., JIAO, Y. C. A loaded wideband linearly tapered slot antenna with broad bandwidth. IEEE Antennas and Wireless Propagation Letters, 2011, vol. 10, p. 79-127.
5. JANASWAMY, R., SCHAUBERT, D. H. Analysis of the tapered slot antenna. IEEE Transactions on Antennas and Propagation, 1987, vol. 35, no. 9, p. 1058-1065.
6. YNGVESSON, K. S., KORZENIOWSKI, T. L., KIM, Y. S., KOLLBERG, E. L., JOHANSSON, J. F. The tapered slot antenna ─ a new integrated element for millimeter-wave applications. IEEE Transactions on Antennas and Propagation, 1989, vol. 37, no. 2, p. 365-374.
7. LANGLEY, J. D. S., HALL, P. S., NEWHAM, P. Balanced antipodal Vivaldi antenna for wide bandwidth phased arrays. IEE proc.-Microwave Antennas and Propagation, 1996, vol. 143, no. 2, p. 97-102.
8. HOOD, A. Z., KARACOLAK, T., TOPSAKAL, E. A small antipodal Vivaldi antenna for ultra-wideband applications. IEEE Antennas and Wireless Propagation Letters, 2008, vol. 7, p. 656 to 660.
9. SUGAWARA, S., MAITA, Y., ADACHI, K., MORI, K., MIZUNO, K. Characteristics of a mm-wave tapered slot antenna with corrugated edges. IEEE MTT-S digest, 1998, p. 533-536.
10. XU, H. Y., ZHANG, H., WANG, J., MA, L. X. A new tapered slot antenna with symmetrical and stable radiation pattern. Progress in Electromagnetics Research Letters, 2008, vol. 5, p. 35-43.
11. ABBOSH, A. M. Miniaturized microstrip-fed tapered slot antenna with ultra-wideband performance. IEEE Antennas and Wireless Propagation Letters, 2009, vol. 8, p. 690-692.
12. KIM, H., JUNG, C. W. Ultra-wideband endfire directional tapered slot antenna using CPW to wide-slot transition. Electronics Letters, 2010, vol. 46, no. 17, p. 1183-1185.
13. ZHU, F. G., GAO, S., HO, A.T.S., BROWN, T.W.C., LI, J. Z., XU, J. D. Low profile directional ultra-wideband antenna for seethrough-wall imaging applications. Progress in Electromagnetics Research, 2011, vol. 121, p. 121-139.

Keywords: UWB impulse radar, UWB imaging, tapered slot antenna, UWB antenna, cross-polarization

M.Khalily, M.K.A.Rahim, A.A.Kishk, S.Danesh [references] [full-text] [Download Citations]
Wideband P-Shaped Dielectric Resonator Antenna

A novel P-shaped dielectric resonator antenna (DRA) is presented and investigated for wideband wireless application. By using P-shaped resonator, a wideband impedance bandwidth of 80% from 3.5 to 8.2 GHz is achieved. The antenna covers all of wireless systems like C-band, 5.2, 5.5 & 5.8 GHz-WLAN & WiMax. The proposed antenna has a low profile and the thickness of the resonator is only 5.12 mm, which is 0.06-0.14 free space wavelength. A parametric study is presented. The proposed DRA is built and the characteristics of the antenna are measured. Very good agreement between numerical and measured results is obtained.

1. CHAIR, R., KISHK, A. A., LEE, K. F., KAJFEZ, D. Performance comparisons between dielectric resonator antennas and printed microstrip patch antennas in the x-band. Microwave Journal, 2006, vol. 49, no. 1.
2. ALMPANIS, G., FUMEAUX, CH., VAHLDIECK, R. Dual-mode bridge-shaped dielectric resonator antennas. IEEE Antennas Wireless Propag. Lett., 2010, vol. 9, p. 103-106.
3. RYU, K. S., KISHK, A. A. Ultra wideband dielectric resonator antenna with broadside patterns mounted on a vertical ground plane edge. IEEE Trans. on Antennas and Propagation, 2010, vol. 58, no. 4, p. 1047-1053.
4. ST. MARTIN, J. T. H., ANTAR, Y. M. M., KISHK, A. A., ITTIPIBOON, A., CUHACI, M. Dielectric resonator antenna using aperture coupling. Electron. Lett., 1990, vol. 26, p. 2015-2016.
5. KRANENBURG, R. A., LONG, S. A., WILLIAMS, J. T. Coplanar waveguide excitation of dielectric resonator antennas. IEEE Trans. Antennas & Propagation, 1991, vol. 39, p. 119-122.
6. SHUM, S. M., LUL, K. M. Stacked annular-ring dielectric resonator antenna excited by axi-symmetric coaxial probe. IEEE Trans. Antennas &Propagation, 1995, vol. 43, p. 889-892.
7. WALSH, A. G., YOUMG, S. D., LONG, S. A. An investigation of stacked and embedded cylindrical dielectric resonator antennas. IEEE Antennas Wireless Propag. Lett., 2006, vol. 5, p. 130-133.
8. KISHK, A. A. Wide-band truncated tetrahedron dielectric resonator antenna excited by a coaxial probe. IEEE Trans. on Antennas and Propagation, 2003, vol. 51, p. 2913-2917.
9. DENIADNI, T. A., RAO, Q. J., SEBAK, A. R. Broadband Lshaped dielectric resonator antenna. IEEE Antennas Wireless Propag. Lett., 2005, vol. 4, p. 453-454.
10. RAO, Q. J., DENIDNI, T. A., SEBAK, A. R. Broadband compact stacked T-shaped DRA with equilateral-triangle cross sections. IEEE Antennas Wireless Propag. Lett., 2006, vol. 5, p. 130-133.
11. CHAIR, R., KISHK, A. A., LEE, K. F. Wideband stair-shaped dielectric resonator antennas. IET Microw. Antennas & Propagation, 2007, vol. 1, no. 2, p. 299-305.
12. ALMPANIS, G., FUMEAUX, CH., VAHLDIECK, R. The trapezoidal dielectric resonator antenna. IEEE Trans. on Antennas and Propagation, 2008, vol. 56, no. 9, p. 2810-2816.
13. LIANG, X. L., DENIDNI, T. A. H-shaped dielectric resonator antenna for wideband applications. IEEE Antennas Wireless Propag. Lett., 2008, vol. 7, p. 163-166.
14. MONGIA, R. K., ITTIPIBOON, A. Theoretical and experimental investigations on rectangular dielectric resonator antennas. IEEE Trans. on Antennas and Propagation, 1997, vol. 45, no. 9, p. 1348-1356.
15. REZAEI, P., HAKKAK, M., FOROORAGHI, K. Design of wideband dielectric resonator antenna with a two segment structure. Progress in Electromagnetics Research, 2006, PIER 66, p. 111-124.
16. MOHSEN KHALILY, MOHAMAD K. A.RAHIM, M. RAMLEE KAMARUDIN A novel P-shape dielectric resonator antenna for wideband application. In IEEE Asia-Pacific Conference on Applied Electromagnetics (APACE,) 2010.
17. CST: Microwave Studio based on the finite integration technique, 2011.

Keywords: Dielectric resonator antenna, wideband, P shape, Q factor

L. Geng, G. M. Wang, C. X. Zhang, X. J. Gao, B. F. Zong [references] [full-text] [Download Citations]
Compact Circularly Polarized Patch Antenna Using a Composite Right/Left-Handed Transmission Line Unit-Cell

A compact circularly polarized (CP) patch antenna using a composite right/left-handed (CRLH) transmission line (TL) unit-cell is proposed. The CRLH TL unit-cell includes a complementary split ring resonator (CSRR) for shunt inductance and a gap loaded with a circular-shaped slot for series capacitance. The CSRR can decrease the TM10 mode resonance frequency, thus reducing the electrical size of the proposed antenna. In addition, the asymmetry of the CSRR brings about the TM01 mode, which can be combined with the TM10 mode by changing the slot radius. The combination of these two orthogonal modes with 90° phase shift makes the proposed antenna provide a CP property. The experimental results show that the proposed antenna has a wider axial ratio bandwidth and a smaller electrical size than the reported CP antennas. Moreover, the proposed antenna is designed without impedance transformer, 90° phase shift, dual feed and ground via.

1. CALOZ, C., ITOH, T. Electromagnetic Metamaterials: Transmission Line Theory and Microwave Applications. HobokenPiscataway: Wiley-IEEE Press, 2005.
2. XU, H.-X., WANG, G.-M., GONG, J.-Q. Compact dual-band zeroth-order resonance antenna. Chinese Physics Letters, 2012, vol. 29, no. 1, p. 014101-1 - 014101-4.
3. NIU, J.-X. Dual-band dual-mode patch antenna based on resonanttype metamaterial tranmission line. Electronics Letters, 2010, vol. 46, no. 4, p. 266 - 267.
4. GIL, M., BONACHE, J., SELGA, J., GARCIA-GARCIA, J., MARTIN, F. Broadband resonant-type metamaterial transmission lines. IEEE Microwave and Wireless Components Letters, 2007, vol. 17, no. 2, p. 97 - 99.
5. LIM, S., CALOZ, C., ITOH, T. Metamaterial-based electronically controlled transmission-line structure as a novel leaky-wave antenna with tunable radiation angle and beamwidth. IEEE Transactions on Microwave Theory and Techniques, 2004, vol. 52, no. 12, p. 2678 - 2690.
6. IKEDA, T., SAKAKIBARA, K., MATSUI, T., KIKUMA, N., HIRAYAMA, H. Beam-scanning performance of leaky-wave slotarray antenna on variable stub-loaded left-handed waveguide. IEEE Transactions on Antennas and Propagation, 2008, vol. 56, no. 12, p. 3611 - 3618.
7. LAI, A., LEONG, K. M. K. H., ITOH, T. Infinite wavelength resonant antennas with monopolar radiation pattern based on periodic structures. IEEE Transactions on Antennas and Propagation, 2007, vol. 55, no. 3, p. 868 - 876.
8. LAI, A., CALOZ, C., ITOH, T. Composite right/left-handed transmission line metamaterials. IEEE Microwave Magazine, 2004, vol. 5, no. 3, p. 34 - 50.
9. NASIMUDDIN, CHEN, Z. N., QING, X. A compact circularly polarized cross-shaped slotted microstrip antenna. IEEE Transactions on Antennas and Propagation, 2012, vol. 60, no. 3, p. 1584 - 1588.
10. NASIMUDDIN, QING, X., CHEN, Z. N. Compact asymmetric-slit microstrip antennas for circular polarization. IEEE Transactions on Antennas and Propagation, 2011, vol. 59, no. 1, p. 285 – 288.
11. WONG, K.-L. Compact and Broadband Microstrip Antennas. New York: Wiley-IEEE Press, 2002.
12. WONG, K.-L., HSU, W.-H., WU, C.-K. Single-feed circularly polarized microstrip antenna with a slit. Microwave and Optical Technology Letters, 1998, vol. 18, no. 4, p. 306 – 308.
13. CHEN, W.-S., WU, C.-K., WONG, K.-L. Novel compact circularly polarized square microstrip antenna. IEEE Transactions on Antennas and Propagation, 2001, vol. 49, no. 3, p. 340 – 342.
14. CHEN, W.-S., WU, C.-K., WONG, K.-L. Single-feed square-ring microstrip antenna with truncated corners for compact circular polarization operation. Electronics Letters, 1998, vol. 34, no. 11, p. 1045 – 1047.
15. CHEN, W.-S., WU, C.-K., WONG, K.-L. Compact circularly polarized microstrip antenna with bent slots. Electronics Letters, 1998, vol. 34, no. 13, p. 1278 – 1279.
16. CHEN, W.-S., WONG, K.-L., WU, C.-K. Inset microstripline-fed circularly polarized microstrip antennas. IEEE Transactions on Antennas and Propagation, 2000, vol. 48, no. 8, p. 1253 – 1254.
17. HA, J., KWON, K., LEE, Y., CHOI, J. Hybrid mode wideband patch antenna loaded with a planar metamaterial unit cell. IEEE Trans. Antennas & Propag., 2012, vol. 60, no. 2, p. 1143 – 1147.

Keywords: Circular polarization, compact patch antenna, composite right/left-handed transmission line, complementary split ring resonator, circular-shaped slot

S. M. Noghabaei, S. K. A. Rahim, P. J. Soh, M. Abedian, G. A. E. Vandenbosch [references] [full-text] [Download Citations]
A Dual-Band Circularly-Polarized Patch Antenna with a Novel Asymmetric Slot for WiMAX Application

A compact design of a circularly-polarized (CP) microstrip antenna to achieve dual-band behavior for WiMAX applications is presented. A single-layered feed is used to excite a single square patch integrated with a novel asymmetrical slot and two different truncated corners to achieve CP polarization in both bands. Besides its structural simplicity, ease of fabrication and low-cost, the proposed antenna features a satisfactory impedance bandwidth of 7.2 % in the lower band (2.53 GHz) and 3.6 % in the upper band (5.73 GHz). The measured radiation pattern of the proposed antenna demonstrates directional patterns in both E- and H-planes with a 3 dB axial ratio of 2 % and 3.2 % in the lower and upper band, respectively.

1. SOLIMAN, E. A., BREBELS, S., BEYNE, E., VANDENBOSCH, G. A. E. Circularly polarized aperture antenna fed by CPW and built in MCM-D technology. Electronics Letters, 1999, vol. 35, p. 250-251.
2. WONG, K. L., WU, J. Y. Single-feed small circularly polarised square microstrip antenna. Electronics Letters, 1997, vol. 33, p. 1833-1834.
3. CHEN, W. S., et al. Novel compact circularly polarized square microstrip antenna. IEEE Transactions on Antennas and Propagation, 2001, vol. 49, p. 340-342.
4. NASIMUDDIN, N., et al. Wideband circularly polarized stacked microstrip antennas. IEEE Antennas and Wireless Propagation Letters, 2007, vol. 6, p. 21-24.
5. ZHAO, G., et al. Design of a broadband dual circularly polarized square slot antenna. Microwave and Optical Technology Letters, 2008, vol. 50, p. 2639-2642.
6. NAYERI, P., et al. Dual-band circularly polarized antennas using stacked patches with asymmetric U-slots. Antennas and Wireless Propagation Letters, IEEE, 2011, vol. 10, p. 285-288.
7. TONG, K. F., WONG, T. P. Circularly polarized U-slot antenna. IEEE Transactions on Antennas and Propagation, 2007, vol. 55, p. 2382-2385.
8. LAM, K. Y., et al. Small circularly polarized U-slot wideband patch antenna. IEEE Antennas and Wireless Propagation Letters, 2011, vol. 10, p. 87-90.
9. YANG, S. S., et al. Design and study of wideband single feed circularly polarized microstrip antennas. Progress in Electromagnetics Research, 2008, vol. 80, p. 45-61.
10. OOI, T.S, RAHIM, S. K. A., KOH, B. P. 2.45 GHz and 5.8 GHz compact dual-band circularly polarized patch antenna. Journal of Electromagnetic Waves and Applications, 2010, vol. 24, p. 1473 to 1482.
11. ZAKARIA, N., RAHIM, S. K. A., OOI, T. S., TAN, K. G., REZA, A. W., RANI, M. S. A. Design of stacked microstrip dual-band circular polarized antenna. Radioengineering, 2012, vol. 21, p. 875-880.
12. LIU, J. C., et al. Single-feed circularly polarized aperture-coupled stack antenna with dual-mode square loop radiator. IEEE Antennas and Wireless Propagation Letters, 2010, vol. 9, p. 887-890.
13. NASIMUDDIN, N., et al. Compact asymmetric-slit microstrip antennas for circular polarization. IEEE Transactions on Antennas and Propagation, 2011, vol. 59, p. 285-288.
14. KUO, J. S., HSIEH, G. B. Gain enhancement of a circularly polarized equilateral-triangular microstrip antenna with a slotted ground plane. IEEE Transactions on Antennas and Propagation, 2003, vol. 51, p. 1652-1656.

Keywords: Microstrip antenna, circularly polarized (CP), dual-band, asymmetrical slot

P. Kadlec, Z. Raida, J. Drinovsky [references] [full-text] [Download Citations]
Multi-Objective Self-Organizing Migrating Algorithm: Sensitivity on Controlling Parameters

In this paper, we investigate the sensitivity of a novel Multi-Objective Self-Organizing Migrating Algorithm (MOSOMA) on setting its control parameters. Usually, efficiency and accuracy of searching for a solution depends on the settings of a used stochastic algorithm, because multi-objective optimization problems are highly non-linear. In the paper, the sensitivity analysis is performed exploiting a large number of benchmark problems having different properties (the number of optimized parameters, the shape of a Pareto front, etc.). The quality of solutions revealed by MOSOMA is evaluated in terms of a generational distance, a spread and a hyper-volume error. Recommendations for proper settings of the algorithm are derived: These recommendations should help a user to set the algorithm for any multi-objective task without prior knowledge about the solved problem.

1. DEB, K., PRATAP, A., AGARWAL, S., MEYARIVAN, T. A fast and elitist multi-objective genetic algorithm: NSGA-II. IEEE Transactions on Evolutionary Computation, 2002, vol. 6, no. 2, p. 182 - 197.
2. COELLO COELLO, C. A., LECHUGA, M. S. MOPSO: A proposal for Multiple Objective Particle Swarm Optimization. In IEEE Congress on Evolutionary Computation. Hawaii (USA), 2002, p. 825 - 830.
3. KUKKONEN, S., LAMPINEN, J. GDE3: The third evolution step of Generalized Differential Evolution. In IEEE Congress on Evolutionary Computation. Edinburgh (Scotland), 2005, p. 443 - 450.
4. DEB, K. Multi-Objective Optimization using Evolutionary Algorithms. Chichester (UK): Wiley, 2001.
5. KUKKONEN, S., LAMPINEN, J. An empirical study of control parameters for the third version of Generalized Differential Evolution (GDE3). In Proceedings of IEEE Congress on Evolutionary Computation, Vancouver (Canada), 2006, p. 2002 – 2009.
6. ZHENG, B., LI, Z., FENG, X. An exploratory study of sorting particle swarm optimizer for multiobjective optimization. In Fourth International Conference on Bio-Inspired Computing BICTA ´09. Hangzhou (China), 2009, p. 112 – 119.
7. KHOA, D. T. Elitist non-dominated sorting GA-II (NSGA-II) as a parameter-less multi-objective genetic algorithm. In Proceedings of IEEE SoutheastCon. Fort Lauderdale (Florida, USA), 2005, p. 359 - 367.
8. KADLEC, P., RAIDA, Z. A novel Multi-Objective Self-Organizing Migrating Algorithm. Radioengineering, 2011, vol. 20, no. 4, p. 804 – 816, 2011.
9. KADLEC, P., RAIDA, Z. Self-Organizing Migrating Algorithm for optimization with general number of objectives. In Proceedings of 22nd International Conference Radioelektronika 2012. Brno (Czech Republic), 2012, p. 111 - 115.
10. ZELINKA, I., LAMPINEN, J. SOMA – Self organizing migrating algorithm. In Proceedings of 6th MENDEL International Conference on Soft Computing. Brno (Czech Republic), 2000, p. 76 – 83.
11. VELDHUIZEN, D. V. Multiobjective evolutionary algorithms: classifications, analyses and new innovations. Ph.D. Thesis, Dayton, OH, Air Force Institute of Technology. Technical report No. AFIT/DS/ENG/99-01, 1999, 270 p.
12. DEB, K., THIELE, L., LAUMANNS, M., ZITZLER, E. Scalable Test Problems for Evolutionary Multi-Objective Optimization. Kanpur (India): Kanpur Genetic Algorithms Lab. (KanGAL), Indian Institute of Technology, 2001. KanGAL Report 2001001.
13. FONSECA, C. M., FLEMING, P. J. An overview of evolutionary algorithms in multi-objective optimization. Evolutionary Computation Journal, 1995, vol. 3, no. 1, p. 416 – 423.
14. MAO, J., HIRASAWA, K., HU, J., MURATA, J. Genetic symbiosis algorithm for multiobjective optimization problem. In Proceedings of the International Workshop on Robot and Human Interactive Communication. Osaka (Japan), 2000, pp. 137 – 142.
15. SCHAFFER, J. D. Some experiments in machine learning using vector evaluated genetic algorithms. Ph.D. Thesis, Nashville, Tennessee, Vanderbilt University.
16. LI, H., ZHANG, Q. Multiobjective optimization problems with complicated Pareto sets, MOEA/D and NSGA-II. IEEE Transactions on Evolutionary Computation, 2009, vol. 13, no. 2, p. 284 – 302.
17. JIN, Y., OKABE, T., SENDHOFF, B. Solving three-objective optimization problems using evolutionary dynamic weighted aggregation: Results and analysis. In Genetic and Evolutionary Computation – GECCO 2003. Berlin: Springer, p. 203 – 214, 2003.
18. ZITZLER, E., DEB, K., THIELE, L. Comparison of multiobjective evolutionary algorithms: Empirical results. Evolutionary Computation Journal, 2000, vol. 8, no. 2, p. 125 – 148.
19. ZITZLER, E., LAUMANNS, M., THIELE, L. SPEA2: Improving the strength Pareto evolutionary algorithm. Technical Report 103, Zurich, Switzerland: Computer Engineering and Networks Laboratory (TIK), Swiss Federal Inst. of Technology (ETH), 2001.
20. NANBO, J., RAHMAT-SAMII, Y. Advances in Particle Swarm Optimization for antenna designs: Real-number, binary, singleobjective and multi-objective implementations. IEEE Transactions on Antennas and Propagation, vol. 6, no. 2, p. 182 – 197, 2002.
21. HARRINGTON, R. F. Time-harmonic Electromagnetic Fields. New York (US): McGraw-Hill, 1961.
22. MARADEI, F. A frequency-dependent WETD formulation for dispersive materials. IEEE Transactions on Magnetics, 2001, vol. 37, no. 5, p. 3303 - 3306.
23. RAIDA, Z. et al. Communication subsystems for emerging wireless technologies. Radioengineering, 2012, vol. 21, no. 4, p. 1036 to 1049.
24. VENKATARAYALU, N. V., RAY, T. Optimum design of YagiUda antennas using computational intelligence. IEEE Transactions on Antennas and Propagation, 2004, vol. 52, no. 7, p. 1811 - 1818.
25. RICHESON, P. D. NEC-2 Manual, Part III: User´s Guide, available at .

Keywords: MOSOMA, sensitivity, control parameters, multi-objective optimization.

V. Sedenka, J. Ciganek, P. Kadlec, Z. Raida, M. Wiktor, M. S. Sarto, S. Greco [references] [full-text] [Download Citations]
Time-Domain Finite Elements for Virtual Testing of Electromagnetic Compatibility

The paper presents a time-domain finite-element solver developed for simulations related to solving electromagnetic compatibility issues. The software is applied as a module integrated into a computational framework developed within a FP7 European project High Intensity Radiated Field – Synthetic Environment (HIRF SE) able to simulate a large class of problems. In the paper, the mathematical formulation is briefly presented, and special emphasis is put on the user point of view on the simulation tool-chain. The functionality is demonstrated on the computation of shielding effectiveness of two composite materials. Results are validated through experimental measurements and agreement is confirmed by automatic feature selective algorithms.

1. HIRF SE High Intensity Radiated Field Synthetic Environment [online]. [cit. 2012-01-23]. Available at WWW: .
2. WEILAND, T. A numerical method for the solution of the eigenvalue problem of longitudinally homogeneous waveguides. Electronics and Communication (AEU), 1977, vol. 31, p. 308.
3. YEE, K. S. Numerical solution of initial boundary value problems involving Maxwell’s equations in isotropic media IEEE Transactions on Antennas and Propagation, 1966, vol. AP-14, no. 5, p. 302 – 307.
4. HARRINGTON, R. F. Field Computation by Moment Method. New York: Macmillan, 1968.
5. JIN, J. M. The Finite Element Method in Electromagnetics. New York: Wiley, 2nd edition, 2002.
6. amelet-hdf - Tool Development for Amelet-HDF Specification. - Google Project Hosting [online]. 2009 [cit. 2012-01-23]. Available at WWW: .
7. BRUNS, H. D., SCHUSTER, C., SINGER, H. Numerical electromagnetic field analysis for EMC problems. IEEE Transactions on Electromagnetic Compatibility, 2007, vol. 49, no. 2, p. 253 – 262.
8. CAORSI, S., CEVINI, G. TDFEM analysis of the scattering properties of shielding structures. In IEEE International Symposium on Electromagnetic Compatibility. Istanbul (Turkey), 2003, p. 288 – 291.
9. LEI, L., XIANG, C., LEI, Q. Simulation of electromagnetic transients of the bus bar in substation by the time-domain finiteelement method. IEEE Transactions on Electromagnetic Compatibility, 2009, vol. 51, no. 4, p. 1017 – 1025.
10. DE MIRANDA, G. C., RIBEIRO, E. J. Lightning electromagnetic fields computation using time domain finite element method. In IEEE International Conference on Wireless Communications and Applied Computational. Honolulu (Hawai), 2005, p. 301 – 304.
11. ZIENKIEWICZ, O.C. A new look at the Newmark, Houbolt and other time stepping formulas. A weighted residual approach. Earthquake Engineering and Structural Dynamics, 1977, vol. 5, p. 413 – 418.
12. JIAO, D., JIN, J. M. A general approach for the stability analysis of the time-domain finite-element method for electromagnetic simulations. IEEE Transactions on Antennas and Propagation, 2002, vol. 50, no. 11, p. 1624 – 1632.
13. TAFLOVE, A., HAGNESS, S .C. Computational Electrodynamics: The Finite-Difference Time-Domain Method. Boston: Artech House, 2nd edition, 2000.
14. TSAI, H. P., WANG, Y., ITOH, T. An unconditionally stable extended (USE) finite-element time-domain solution of active nonlinear microwave circuits using perfectly matched layer. IEEE Transactions on Microwave Theory and Techniques, 2002, vol. 50, no. 10, p. 2226 – 2232.
15. www.gidhome.com [online]. 2011 [cit. 2012-01-23]. What's GiD. Available at WWW: .
16. SSI: Scalable Software Infrastructure for Scientific Computing: Lis: a Library of Iterative Solvers for Linear Systems. [online]. 2011 [cit. 2011-12-31]. Available at WWW: .
17. GRECO, S., TAMBURRANO, A., D’ALOIA, A., MUFFATI, R., SARTO, M. S. Shielding effectiveness properties of carbon-fiber reinforced composite for HIRF applications. In EMC Europe 2012 Int. Symp. on EMC. Rome (Italy), 17-21 Sept., 2012.
18. BOZZETTI, M., PISU, L., GRECO, S., SARTO, M. S. Shielding performance of an expanded copper foil over a wide frequency range. In EMC Europe 2011, Int. Symp. on EMC. York (UK), Sept. 2011.
19. SARTO, M. S., TAMBURRANO, A. An innovative test method for the shielding effectiveness measurement of conductive thin films in a wide frequency range. IEEE Transactions on EMC, 2006, vol. 48, no. 2, p. 331 – 341.
20. ASTM-D-4935, Standard method for measuring the electromagnetic shielding effectiveness of planar materials, Sept. 1989.
21. GCEM Validation Tool [online]. [cit. 2012-10-10]. Available at WWW:
22. DUFFY, A. P., MARTIN, A. J. M., ORLANDI, A., ANTONINI, G., BENSON, T. M., WOOLFSON, M. S. Feature selective validation (FSV) for validation of computational electromagnetics (CEM). Part I – The FSV Method. IEEE Transactions on EMC, 2006, vol. 48, no. 3, p. 449-459.

Keywords: Amelet-HDF, electromagnetic compatibility (EMC), high intensity radiated field synthetic environment (HIRF SE), shielding effectiveness (SE), time domain finite elements (TDFE), composite materials.

P. Kovacs, J. Puskely [references] [full-text] [Download Citations]
Stacked High-Impedance Surface (HIS) for 5 GHz WLAN Applications

In this work we present a stacked high-impedance surface (HIS) for low-profile, high-gain, 5 GHz WLAN antennas. The structure consists of two layers: a lower mushroom layer and an upper planar layer. We demonstrate that the stacked geometry has much better properties than conventional single-layer structures for achieving simultaneously surface-wave suppression and zero reflection phase at a given frequency. We show by measurements that the designed stacked HIS exhibits both a large band gap and in-phase wave reflection over the entire range from 4.6 GHz to 6.4 GHz. The structure is realized on FR4 substrate using standard etching technology to make fabrication easy and cheap.

1. SIEVENPIPER, D. F., ZHANG, L., BROAS, R. F. J., ALEXOPOULOS, N. G., YABLONOVITCH, E. High-impedance electromagnetic surfaces with a forbidden frequency band. IEEE Trans. Microw. Theory Tech., Nov. 1999, vol. 47, p. 2059 – 2074.
2. AMINIAN, A., YANG, F., RAHMAT-SAMII, Y. In-phase reflection and EM wave suppression characteristics of electromagnetic bandgap ground planes. In Proc. IEEE AP-S Int. Symp., June 22 – 27, 2003, vol. 4, p. 430 – 433.
3. CLAVIJO, S., DIAZ, R. E., MCKINZIE, W. E. Design methodology for Sievenpiper high-impedance surfaces: an artificial magnetic conductor for positive gain electrically small antennas. IEEE Trans. Antennas Propag., Oct. 2003, vol. 51, p. 2678 – 2690.
4. LI, L., CHEN, Q., YUAN, Q., LIANG, C., SAWAYA, K. Surfacewave suppression bandgap and plane-wave reflection phase band of mushroomlike photonic bandgap structures. J. Appl. Phys., Jan. 2008, vol. 103, no. 2, ID 023513.
5. KOVACS, P., RAIDA, Z., LUKES, Z. Design and optimization of periodic structures for simultaneous EBG and AMC operation. In Proceedings of the 16th Conference on Microwave Techniques. Brno: Czechoslovakia Section IEEE, April 2010, p. 195-198.
6. ABHARI, R., ELEFTHERIADES, G. V. Metallo-dielectric electromagnetic bandgap structures for suppression and isolation of the parallel-plate noise in high-speed circuits. IEEE Trans. Microw. Theory Tech., June 2003, vol. 51, p. 1629 – 1639.
7. FERESIDIS, A. P., APOSTOLOPOULOS, G., SERFAS, N., VARDOXOGLOU, J. C. Closely coupled metallodielectric electromagnetic band-gap structures formed by double-layer dipole and tripole arrays. IEEE Trans. Antennas Propag., May 2004, vol. 52, p. 1149 – 1158.
8. BROAS, R. F. J., SIEVENPIPER, D. F., YABLONOVITCH, E. High-impedance ground plane applied to a cellphone handset geometry. IEEE Trans. Microw. Theory Tech., July 2001, vol. 49, p. 1262 – 1265.

Keywords: Antenna, high-impedance surface (HIS), in-phase wave reflection, surface-wave

R. Keshavarz, M. Movahhedi [references] [full-text] [Download Citations]
A Compact and Wideband Coupled-Line Coupler with High Coupling Level Using Shunt Periodic Stubs

A wideband microstrip forward-wave coupled-line coupler with high coupling value is presented. Compared with the conventional edge-coupled microstrip forward-wave coupler, this symmetrical structure, consisting periodic shunt stubs between the two coupled-lines, achieves wider operating bandwidth and larger coupling level. To characterize this structure, the equivalent circuit model is established and verified by measurement and full-wave results. The designed and fabricated prototype is a 0-dB forward-wave coupler with 0.6 mm stub length. This coupler exhibits a coupled amplitude balance of ±2 dB, good matching (15dB) and at least 15dB isolation between adjacent ports over a wide bandwidth of 66% from 2 GHz to 4 GHz centered at 3 GHz. The coupled-line length and width of the proposed structure are approximately λ_g/2 and λ_g/13, respectively, which makes it more compact than the conventional forward coupled-line couplers.

1. MONGIA, R., BAHL, I., BHARTIA, P., RF and Microwave Coupled-Line Circuits. Norwood, MA: Artech House, 1999.
2. IKALAINEN, K., MATTHAEI, L. Wide-band, forward-coupling microstrip hybrids with high directivity. IEEE Transactions on Microwave Theory and Techniques, 1987, vol. 35, no. 8, p. 719 to 725.
3. FUJII, T., OHTA, I. Size-reduction of coupled-microstrip 3-dB forward couplers by loading with periodic shunt capacitive stubs. In IEEE MTT-S International Microwave Symposium Digest, 2005, p. 1235–1238.
4. HIROTA, N., TAHARA, Y., YONEDA, N. A compact forward coupler using coupled composite right/left-handed transmission lines. IEEE Trans. on Microwave Theory and Techniques, 2009, vol. 57, no. 12, p. 3127–3133.
5. HSU, S., WU, T. A novel microstrip forward directional coupler based on an artificial substrate. In European Microwave Conference (EuMC). 2010, p. 926-930.
6. KESHAVARZ, R. MOVAHHEDI, M. HAKIMI, A. A compact 0-dB coupled-line forward coupler by loading with shunt periodic stubs. In Asia-Pacific Microwave Conference Proceedings (APMC), 2011, p. 1248-1251.
7. CALOZ, C., ITOH, T. Electromagnetic Metamaterials: Transmission Line Theory and Microwave Applications. Hoboken, NJ: Wiley, 2006.
8. KAWAKAMI, T., INOUE, N., HORIIE, Y., KITAMURA, T. A super-compact 0dB/3dB forward coupler composed of multilayered CRLH transmission lines with double left-handed shuntinductors, European Microwave Conference (EuMC), 2010, p. 1409-1413.
9. LAURO, S. E., TOSCANO, A., VEGNI, L. Symmetrical coupled microstrip lines with epsilon negative metamaterial loading. IEEE Transactions on Magnetics, 2009, vol. 45, no. 7, p. 1182-1189.
10. CHANG, Y., QIAN, M., ITOH, T. Enhanced forward coupling phenomena between microstrip lines on periodically patterned ground plane. In IEEE MTT-S International Microwave Symposium Digest, 2001, p. 2039–2042.
11. BAHL, I. Lumped Elements for RF and Microwave Circuits. Boston: Artech House, 2003.
12. HSU, S.-K., TSAI, C.-H., WU, T.-L. A novel miniaturized forward-wave directional coupler with periodical mushroom-shaped ground plane. IEEE Transaction on Microwave Theory and Techniques, 2010, vol. 58, no. 7, p. 2277-2283.

Keywords: Coupled-line couplers, periodic structures, forward-wave couplers, shunt stubs, wideband microwave devices.

S. V. Makki, A. Ahmadi, S. Majidifar, H. Sariri, Z. Rahmani [references] [full-text] [Download Citations]
Sharp Response Microstrip LPF using Folded Stepped Impedance Open Stubs

A novel microstrip lowpass filter with high selectivity and wide stopband is proposed that comprises two lateral folded open stubs and a central mirrored semi-circle ended suppressing cell. The proposed filter has cut-off frequency of 2.28 GHz and is very compact. The stopband width with attenuation level more than -20 dB is equal to 5.47 f_c and the transition band is only 0.14 GHz. This filter is designed, fabricated and measured and the simulated and measured results are in good agreement

1. FU, S.-H., TONG, C.-M., LI, X.-M., ZHANG, W., SHEN, K. Compact miniaturized stepped impedance lowpass filter with sharp cutoff characteristic. Microwave and Optical Technology Letters, 2009, vol. 51, no. 10, p. 2257-2258.
2. LI, L., LI, Z.-F., MAO, J.-F. Compact lowpass filters with sharp and expanded stopband using stepped impedance hairpin units. IEEE Microwave and Wireless Components Letters, 2010, vol. 20, no. 6, p. 310-312.
3. KARTHIKEYAN, S. S., KSHETRIMAYUM, R. S. Compact, deep, and wide rejection bandwidth low-pass filter using open complementary split ring resonator. Microwave and Optical Technology Letters, 2011, vol. 53, no. 4, p. 845-848.
4. KE, L., WANG, G.-M., YU, Z. W. Wide stopband and sharprejection low-pass filter using uniplanar double spiral resonators. Microwave and Optical Technology Letters, 2011, vol. 53, no. 10, p. 2345-2348.
5. CHEN, W.-L., WANG, G.-M., CHEN, G.-D., YAO, G.-F. Enhancement of microstrip stepped-impedance lowpass filters using fractal shapes. Microwave Journal, 2009, vol. 52, no. 7.
6. CHEN, W.-L., WANG, G. M., QI, Y. N. A compact wide stopband Koch-shaped electromagnetic bandgap microstrip lowpass filter. Microwave Journal, 2007, vol. 50, no. 10.
7. GE, L., WANG, J. P., GUO, Y.-X. Compact microstrip lowpass filter with ultra-wide stopband. Electronics Letters, 2010, vol. 46, no. 10, p. 689-691.
8. MA, K., YEO, K. S. New ultra-wide stopband low-pass filter using transformed radial stubs. IEEE Transactions on Microwave Theory and Techniques, 2011, vol. 59, no. 3, p. 604-611.
9. VELIDI, V. K., SANYAL, S. Sharp roll-off lowpass filter with wide stopband using stub-loaded coupled-line hairpin unit. IEEE Microwave and Wireless Components Letters, 2011, vol. 21, no. 6, p. 301-303.
10. HONG, J.-S., LANCASTER, M. J. Microstrip Filters for RF/Microwave Applications. John Wiley & Sons, Inc., 2001.

Keywords: Low pass filter, microstrip technology, folded open stub, sharp response, wide stopband

C. A. Valagiannopoulos [references] [full-text] [Download Citations]
Electromagnetic Absorption of Gaussian Beams by a Grounded Layered Structure

A layered structure of magnetodielectric slabs, backed with a perfectly conducting plane, is illuminated by a Gaussian beam. The permittivities and permeabilities of each layer are selected so that the incident field penetrates smoothly into the subsequent layers and sustains gradually greater losses when reaching the internal ones. The performance of the device as an absorber is estimated through a newly defined indicator and it has been found that the absorbing capacity of the structure could be very high. This qualitative factor is robust and efficient when identifying which of the considered parameters are critical or insignificant as far as the performance of the layered configuration is concerned.

1. LUUKKONEN, O., COSTA, F., SIMOVSKI, C. R., MONORCHIO, A., TRETYAKOV, S. A. A thin electromagnetic absorber for wide incidence angles and both polarizations. IEEE Transactions on Antennas and Propagation, 2009, vol. 57, no. 10, p. 3119 - 3125.
2. CHENG, Q., CUI, T. J., JIANG, W. X., CAI, B. G. An omnidirectional electromagnetic absorber made of metamaterials.New Journal of Physics, 2010, vol. 12, 063006.
3. BREGAR, V. B. Advantages of ferromagnetic nanoparticle composites in microwave absorbers.IEEE Transactions on Magnetics, 2004, vol. 40, no. 3, p. 1679 - 1684.
4. ZIOLKOWSKI, R. W. The design of Maxwellian absorbers for numerical boundary conditions and for practical applications using engineered artificial materials. IEEE Transactions on Antennas and Propagation, 1997, vol. 45, no. 4, p. 656 - 671.
5. KRIEZIS, E. E., PANDELAKIS, P. K., PAPAGIANNAKIS, A. G. Diffraction of a Gaussian beam from a periodic planar screen. Journal of the Optical Society of America A, 1994, vol. 11, no. 2, p. 630 - 636.
6. LANDRY, G. D., MALDONADO, T. A. Gaussian beam transmission and reflection from a general anisotropic multilayer structure. Applied Optics, 1996, vol. 35, no. 30, p. 5870 - 5879.
7. KHALED, E. E. M., HILL, S. C., BARBER, P. W. Scattered and internal intensity of a sphere illuminated with a Gaussian beam. IEEE Transactions on Antennas and Propagation, 1993, vol. 41, no. 3, p. 295 - 303.
8. KATSAV, M., HEYMAN, E. Gaussian beam summation representation of a two-dimensional Gaussian beam diffraction by a half plane. IEEE Transactions on Antennas and Propagation, 2007, vol. 55, no. 8, p. 2247 - 2257.
9. PAUK, L., SKVOR, Z. FDTD stability: critical time increment, Radioengineering, 2003, vol. 12, no. 2, p. 16 - 22.
10. VALAGIANNOPOULOS, C. A. A novel methodology for estimating the permittivity of a specimen rod at low radio frequencies. Journal of Electromagnetic Waves and Applications, 2010, vol. 24, no. 5- 6, p. 631 - 640.
11. YANG, J., HUANG, M. YANG, C. SHI, J. Arbitrary shape electromagnetic transparent device based on Laplaces equation. Radioengineering, 2011, vol. 20, no. 1, p. 307 - 311.
12. On-line Integrator from Wolfram Research. [Online] Available at: http://integrals.wolfram.com/index.jsp.
13. VALAGIANNOPOULOS, C. A. Effect of cylindrical scatterer with arbitrary curvature on the features of a metamaterial slab antenna. Progress in Electromagnetic Research, 2007, vol. 71, p. 59 - 83.
14. VALAGIANNOPOULOS, C.A., TSITSAS, N. L. Linearization of the T-matrix solution for quasi-homogeneous scatterers. Journal of the Optical Society of America A, 2009, vol. 26, no. 4, p. 870 - 881.
15. VALAGIANNOPOULOS, C. A. Electromagnetic scattering of the field of a metamaterial slab antenna by an arbitrarily positioned cluster of metallic cylinders. Progress in Electromagnetic Research, 2011, vol. 114, p. 51 - 66.
16. VALAGIANNOPOULOS, C. A. On adjusting the characteristics of a low-index slab antenna with a finite set of metallic pins. InProceedings of the 5th European Conference on Antennas and Propagation (EUCAP). Rome (Italy), 2011, p. 913 - 917.
17. VALAGIANNOPOULOS, C. A. Closed-form solution to the scattering of a skew strip field by metallic pin in a slab. Progress in Electromagnetic Research, 2008, vol. 79, p. 1 - 21.
18. VALAGIANNOPOULOS, C. A., UZUNOGLU, N. K. Rigorous analysis of a metallic circular post in a rectangular waveguide with step discontinuity of sidewalls. IEEE Transactions on Microwave Theory and Techniques, 2007, vol. 55, no. 8, p. 1673 - 1684.
19. VALAGIANNOPOULOS, C. A. A novel methodology for estimating the permittivity of a specimen rod at low radio frequencies. Journal of Electromagnetic Waves and Applications, 2010, vol. 24, no. 5- 6, p. 631 - 640.
20. VALAGIANNOPOULOS, C. A., SIHVOLA, A. H. On modeling perfectly conducting sharp corners with magnetically inert dielectrics of extreme complex permittivities. IEEE Transactions on Antennas and Propagation, 2012, vol. 60, no. 10, p. 4777 - 4784.
21. VALAGIANNOPOULOS, C. A., ALITALO, P. Electromagnetic cloaking of cylindrical objects by multilayer or uniform dielectric claddings. Physical Review B, 2012, vol. 85, 115402.

Keywords: Electromagnetic absorber, Gaussian beam, Linear superposition.

P. Barcik, L. Hudcova [references] [full-text] [Download Citations]
Measurement of Spatial Coherence of Light Propagating in a Turbulent Atmosphere

A lot of issues have to be taken into account when designing a reliable free space optical communication link. Among these are e.g.,beam wander, fluctuation of optical intensity and loss of spatial coherence that are caused by atmospheric turbulence. This paper presents experimental measurements of spatial coherence of a laser beam. The experimental setup is based on Young's double pinhole experiment. Fringe patterns under atmospheric turbulence for four different pinhole separations are presented. From these fringe patterns, visibility is determined and the coherence radius is estimated.

1. MUHAMMAD, S. S., PLANK, T., LEITGEB, E., FRIEDL, A., ZETTL, K., JAVORNIK, T., SCHMITT, N. Challenges in establishing free space optical communications between flying vehicles. In 6 th International Symposium on Commmunications Systems, Networks and Digital Signal Processing (CNSDSP). Graz (Austria), 2008, p. 82 - 86.
2. WALTHER, F. G., MOORES, J. D., MURPHY, R. J., MICHAEL, S., NOWAK, G. A. A process for free-space laser communications system design. Free-Space Laser Communications IX; Proceedings of SPIE, 2009, vol. 74640V, doi:10.1117/12.826256.
3. HAMMEL, S., MCBRYDE, K., REINHARDT, C. Measurement and modeling of beam wander. Atmospheric Optics IV: Turbulence and Propagation; Proceedings of SPIE, 2011, vol. 81610F, doi:10.1117/12.896597.
4. CHEN JING, AI YOUNG Laser signal intensity and aperture averaging analysis in 16 km free-space optical links. In Symposium on Photonics and Optoelectronic (SOPO). Chengdu (China), 2010, p. 1 - 4, doi: 10.1109/SOPO.2010.5504015.
5. KHALIGHI, M. A., SCHWARTZ, N., AITAMER, N., BOURENNAME, S. Fading reduction by aperture averaging and spatial diversity in optical wireless systems. Journal of Optical Communications and Networking, 2009, vol. 1, no. 6, p. 580 - 593, doi: 10.1364/JOCN.1.000580.
6. REDDING, B., CHOMA, M. A., CAO, H. Spatial coherence of random laser emission. Optics letters, 2011. vol. 36, no. 17, p. 3404 - 3406.
7. LUNDEBERG, L. D. A., LOUSBERG, G. P., BOIKO, D. L., KAPON, E. Spatial coherence measurements in arrays of coupled vertical cavity surface emitting lasers.Applied Physics Letters, 2007, vol. 90, no. 2, p. 021103 - 021103-3, doi: 10.1063/1.2431474.
8. REDDING, B., CHOMA, M. A., CAO, H. Spatially incoherent random lasers for full field optical coherence tomography. Conference Lasers and Electro-Optics (CLEO). Baltimore (USA), 2011.
9. ANDREWS, L. C., PHILLIPS, R. L. Laser Beam Propagation through Random Media. Washington (USA): SPIE Press, 2005.
10. SHAIK, K. S. Atmospheric propagation effects relevant to optical communication. TDA Progress Report 42-94, 1988, p. 180 - 200.
11. HLUBINA, P. Temporal coherence and mode structure of the He-Ne laser beam spectrum. Optoelectronics Review, 1996, vol. 4, no. 3/4, p. 117 - 122.
12. MANDEL, L., WOLF, E. Optical Coherence and Quantum Optics. Cambridge University Press, 1995.
13. POPOOLA, W. O. Subcarrier Intensity Modulated Free-Space Optical Communication Systems. Ph.D. thesis. Newcastle (UK): University of Northumbria, 2009.
14. ANDREWS, L. C. Field Guide to Atmospheric Optics. Washington (USA): SPIE Press, 2004.
15. WANG, S., YANG, S. H., WU, X., ZHAO, C. M., ZHU, Q. H. Experimental study on influence of atmospheric turbulence on coherence of dual-frequency laser.Chinese Physics Letters, 2010, vol. 27, no. 8.

Keywords: Atmospheric turbulence, spatial coherence, Young's experiment, fringe pattern, coherence radius.

V. Matejec, I. Kasik, O. Podrazky, J. Aubrecht, M. Frank, M. Jelinek, V. Kubecek [references] [full-text] [Download Citations]
Preparation and Characterization of Bragg Fibers for Delivery of Laser Radiation at 1064 nm

Bragg fibers offer new performance for transmission of high laser energies over long distances. In this paper theoretical modeling, preparation and characterization of Bragg fibers for delivery laser radiation at 1064 nm are presented. Investigated Bragg fibers consist of the fiber core with a refractive index equal to that of silica which is surrounded by three pairs of circular layers. Each pair is composed of one layer with a high and one layer with a low refractive index and characterized by a refractive-index difference around 0.03. Propagation constants and radiation losses of the fundamental mode in such a structure were calculated on the basis of waveguide optics. Preforms of the Bragg fibers were prepared by the MCVD method using germanium dioxide, phosphorous pentoxide and fluorine as silica dopants. The fibers with a diameter of 170 m were drawn from the preforms. Refractive-index profiles, angular distributions of the output power and optical losses of the prepared fibers were measured. Results of testing the fibers for delivery radiation of a pulse Nd:YAG laser at 1064 nm are also shown.

1. PIERRE, S. A., ALBALA, D. M. The future of lasers in urology. World J. Urol., 2007, vol. 25, p. 275–283.
2. NAZIF, O. A., TEICHNAN, J. M. H., GLICKMAN, R. D., WELCH, A. J. Review of laser fibers: a practical guide for urologists. J. Endourology, 2004, vol. 18, no. 9, p 818–829.
3. BLACKMON, R. L., IRBY, P. B., FRIED, N. M. Thulium fiber laser lithotripsy using tapered fibers. Lasers in Surgery and Medicine, 2010, vol. 42, p. 45–50.
4. GEORGE, R., WALSH, L. J. Performance assessment of novel side firing flexible optical fibers for dental applications. Lasers in Surgery and Medicine, 2009, vol. 41, p. 214–221.
5. BAUERLE, D. Laser Processing and Chemistry. 3rd ed. BerlinHeidelberg-New York: Springer, 2000.
6. HARRINGTON, J. A. An overview of power delivery and laser damage in fibers. In Proc. SPIE Vol. 2966 – Laser-Induced Damage in Optical Materials, 1966, p. 536-544.
7. POLLETTO, T. J., NGO, A. K., TCHAPYJNIKOV, A., LEVIN, K., TRAN, D., FRIED, N. M. Comparison of germanium oxide fibers with silica and sapphire fiber tips for transmission of erbium: YAG laser radiation. Lasers in Surgery and Medicine, 2006, vol. 38, p. 787–791.
8. MERBERG, G. N. Current status of infrared fiber optics for medical laser power delivery. Lasers in Surgery and Medicine, 1993, vol. 13, no. 5, p. 572–576.
9. KANDILLI, C., TURKOGLU, A. K., ULGEN, K. Transmission performance of fibre-optic bundle for solar lighting. Int. J. Energy Res,. 2009, vol. 33, p. 194–204.
10. BIRYUKOV, A. S., DIANOV, E. M. Energy transfer in optical fibres. Quant. Electr., 2007, vol. 37, no. 4, p. 379-382.
11. ARI, M., TAPLAMACIOGLU, M. C. Electrical power over fiber optics. J. Technical Physical Problems Engineering, 2010, vol. 1, no. 4, p. 84-91.
12. SATO, S., SHI, Y. W., MATSUURA, Y., MIYAGI, M., ASHIDA, H. Hollow-waveguide-based nanosecond, near infrared pulsed laser ablation of tissue. Lasers in Surgery and Medicine, 2005, vol. 37, no. 2, p.149–154.
13. SHI, Y. W., ITO, K., MATSUURA, Y., MIYAGI, M. Multiwavelength laser light transmission of hollow optical fiber from the visible to the mid-infrared. Opt. Letters, 2005, vol. 30, no. 21, p. 2867–2869.
14. MIYAGI, M., AKIHITO, H. Hollow waveguide and method of making same. US Patent number: 5995696. Filing date: Dec 15, 1997, Issue date: Nov 30, 1999.
15. BENDADA, A., COLE, K., LAMONTAGNE, M., SIMARD, Y. Infrared radiometry using a dielectric-silver-coated hollow glass waveguide for polymer processing. Infrared Physics Technology, 2004, vol. 45, p. 59–68.
16. CREGAN, R. F., MANGAN, B. J., KNIGHT, J. C., BIRKS, T. A., RUSSELL, P., ROBERTS, P. J., ALLAN, D. C. Single-mode photonic band gap guidance of light in air. Science, 1999, vol. 285, p. 1537–1539.
17. ROBERTS, P. J., COUNY, F., SABERT, H., MANGAN, B. J., WILLIAMS, D. P., FARR, L., MASON, M. W., TOMLINSON, A., BIRKS, T. A., KNIGHT, J. C., RUSSELL, P. St. J. Ultimate low loss of hollow-core photonic crystal fibres. Opt. Express, 2005, vol. 13, no. 1, p. 236–244.
18. KONOROV, S. O., FEDOTOV, A. B., KOLEVATOVA, O. A., BELOGLAZOV, V. I., SKIBINA, N. B., SCHCERBAKOV, A. V., WINTNER, E., ZHELTIKOV, A. M. Laser breakdown with millijoule trains of picosecond pulses transmitted through a hollow-core photonic-crystal fibre. J. Phys, 2003, vol. D36, p. 1375 to 1381.
19. RADZIEMSKY, L. J., CREMERS, D. A (Eds.). Laser-Induced Plasmas and Applications (Optical Engineering). Marcel Dekker Ltd., 1989.
20. SHEPHARD, J. D. JONES, J. D. C., HAND, D. P., BOUWMANS, G., KNIGHT, J. C., RUSSELL, P.S., MANGAN, B. J. High energy nanosecond laser pulses delivered single-mode through hollow-core PBG fibers. Opt. Express, 2004, vol. 12, 2004, p. 717 to 723.
21. URICH, A., MAIER, R. P. J., MANGAN, B. J., RENSHAW, S., KNIGHT, J. C., HAND, D. P., SHEPHARD, J. D. Delivery of high energy Er:YAG pulsed laser light at 2.94 µm through a silica hollow core photonic crystal fibre. Opt. Express, 2012, vol. 20, p. 6677-6684.
22. TAUER, J., ORBAN, F., KOFLER, H., FEDOTOV, A. B., FEDOTOV, I. V., MITROKHIN, V. P., ZHELTIKOV, A. M. , WINTNER, E. High-throughput of single high-power laser pulses by hollow photonic band gap fibers. Laser Phys. Letters, 2007, vol. 4, no. 6, p. 444–448.
23. LIKCHACHEV, M. E., SEMJONOV, S. L., BUBNOV, M. M., DIANOV, E. M., KHOPIN, V. F., SALGANSKII, M. Y., GURJANOV, M. A., GURJANOV, A. N., JAMIER, R., VIALE, P., FEVRIER, S., BONDY, J.-M. Development and study of Bragg fibres with a large mode field and low optical losses. Quant. Electr., 2006, vol. 36, no. 7, p. 581-586.
24. VIENNE, G., XU, Y., JAKOBSEN, C., DEVERL, H.-J., JENSEN, J., SORENSEN, T., HANSEN, T. P., HUANG, Y., TERREL, M., LEE, R. K., MORTENSEN, N. A., BROENG, J., SIMONSEN, H., BJARKLEV, A., YARIV, A. Ultra-large bandwidth hollow-core guiding in all-silica Bragg fibers with nano-supports. Opt. Express, 2004, vol. 12, no. 15, p. 3500–3508.
25. FEVRIER, S., JAMIER, R., BLONDY, J. M., SEMJONOV, S. L., LIKCHACHEV, M. E., BUBNOV, M. M., DIANOV, E. M., KHOPIN, V. F., SALGANSKII, M. Y., GURYANOV, A. N. Lowloss singlemode large mode area all-silica photonic bandgap fiber. Opt. Express, 2006, vol. 14, no. 2, p. 562–569.
26. JAMIER, R., FEVRIER, S., HUMBERT, G., DEVAUTOUR, M., VIALE, P, BLONDY, J. M, SEMJONOV, S. L., LIKCHACHEV, M. E., BUBNOV, M. M., DIANOV, E. M., KHOPIN, V.F., SALGANSKII, M. Y., GURYANOV, A. N. Reduction of bend loss in large-mode-area Bragg fibres. In Proc. SPIE Vol. 6588- Photonic Crystal Fibres, 2007, p. 58805.
27. JELINEK, M., KUBECEK, V. 15 ps quasi-continuously pumped passively mode-locked highly doped Nd:YAG laser in bounce geometry. Laser Phys. Lett., 2011, vol. 8, p. 657-660.
28. YEH, P., YARIV, A., MAROM, E. Theory of Bragg fiber. J. Am. Opt. Soc., 1978, vol. 68, p. 1196-1201.
29. GUO, S., ALBIN, S. Comparative analysis of Bragg fibers. Opt. Express, 2004, vol. 12, p. 198-207.
30. SCHERER, G. W. Stress-induced index profile distortion in optical waveguides. Appl. Opt., 1980, vol. 19, no. 12, p. 2000-2006.

Keywords: Bragg fibers, high-index contrast, MCVD method, transmission characteristics.

O. Barkman, V.Jerabek, V.Prajzler [references] [full-text] [Download Citations]
Optical Splitters Based on Self-Imaging Effect in Multi-Mode Waveguide Made by Ion Exchange in Glass

Design and modeling of single mode optical multi-mode interference structures with graded refractive index is reported. Several samples of planar optical channel waveguides were obtained by Ag⁺<->Na⁺ and K⁺<->Na⁺ one step thermal ion exchange process in molten salt on GIL49 glass substrate and new special optical glass for ion exchange technology. Waveguide properties were measured by optical mode spectroscopy. Obtained data were used for further design and modeling of single mode channel waveguide and subsequently for the design of 1 to 3 multimode interference power splitter in order to improve simulation accuracy. Designs were developed by utilizing finite difference beam propagation method.

1. BACHMANN, M., BESSE, P. A., MELCHIOR, H. General selfimaging properties in N x N multimode interference couplers including phase relations. Applied Optics, 1994, vol. 33, no. 18, p. 3905-3911.
2. SOLDANO, L. B., PENNINGS, E. C. M. Optical multi-mode interference devices based on self-imaging: Principles and applications. Journal of Lightwave Technology, 1995, vol. 13, no.4, p. 615-627.
3. TAKAHASHI, H. Planar lightwave circuit devices for optical communication. Proc. of SPIE, 2003, vol. 5246, p. 520-531.
4. WEST, B., GUPTA, M. C., BALLATO, J. Handbook of Photonics: Ion-exchanged Glass Waveguides. CRC Press, 2007.
5. PEREIRA, M. B., PELLI, S., RIGHINI, G. C., HOROWITZ, F., K + /Ag+ ion-exchange glass waveguides: Concentration and graded-index profile analysis from EDS, m-line and DNS measurements. In Annals of Optics-XXV ENFMC, 2002, p. 108-111.
6. METRICON, Metricon Model 2010/M Overview. [Online] Cited 2012-12-20. Available at: http//:www.metricon.com
7. RSOFT DESIGN GROUP, RSoft CAD Enviroment 8.1, User Guide, 2008.
8. RSOFT DESIGN GROUP, BeamPROP 8.1 User guide, 2008.
9. DAS, S., GERAGHTY, D., HONKANEN, S., PEYGHAMBARIAN, N. MMI splitters by ion-exchange in glass. Proceedings SPIE 3936, Integrated Optics Devices IV, 2000, p. 239-247.
10. KASPRZAK, D., BLAHUT, M., MACIAK, E. Applications of multimode interference effects in gradient waveguides produced by ion-exchange in glass. European Physical Journal Special Topics, 2008, vol. 154, p. 113-116.

Keywords: Ion exchange, glass substrate, single mode channel waveguide, power splitter, multi-mode interference.

P. Lafata, J. Vodrazka [references] [full-text] [Download Citations]
Application of Fiber Ring for Protection of Passive Optical Infrastructure

Today, passive optical networks (PONs) are mostly used as modern high-speed access networks for various applications. However, there are also several specific applications, such as in business, office, army or science sector, which require a complex protection and backup system against failures and malfunctions. Typically, tree or star topologies are used for passive optical networks PONs. These topologies are vulnerable mainly against the failures of central optical line termination (OLT) unit. This paper presents an innovative method for protecting PONs by using ring topologies, especially the OLT unit. The method is described in the article, and an elementary mathematical model for calculations of asymmetric passive optical splitters together with an example is included as well.

1. ITU-T G.987.1. 10-Gigabit-capable Passive Optical Network (XGPON) Systems: Definitions, Abbreviations, and Acronyms. ITU-T, 2010.
2. IEEE Standard 802.3av-2009. Amendment 1: Physical Layer Specifications and Management Parameters for 10 Gb/s Passive Optical Networks. IEEE 802.3av 10G-EPON Task Force, 2009.
3. LAM, C. F. Passive Optical Networks: Principles and Practice. Burlington (USA): Academic Press of Elsevier Inc., 2007.
4. GIRARD, A. FTTx PON, Technology and Testing. Quebec City (Canada): EXFO Electro-Optical Engineering Inc., 2005.
5. MACHUCA, C. M., CHEN, J., WOSINKA, L. PON protection architectures achieving total cost reduction. In Asia Communications and Photonics Conference and Exhibition (ACP). Shanghai, 2010, p. 707-708.
6. SEOL, D.-M., JUNG, E.-S., KIM, B.-W. A simple passive protection structure in a ring-type hybrid WDM/TDM-PON. In The 11th International Conference on Advanced Communication Technology ICACT 2009. Korea, 2009, p. 447-449.
7. HAN, K.-E., SHIM, S.-H., OH, B.-J., PENG, L.-M., KIM, Y.-Ch. Hybrid protection architecture against multipoint failure in WDMPON. In The 9th International Conference on Advanced Communication Technology ICACT 2007. Korea, 2007, p. 1385-1390.
8. CARVALHO, M. M., De SOUZA, E. A. A novel protection mechanism in TDM-PON. In The 11th International Conference on Transparent Optical Networks, ICTON. Azores (Portugal), 2009.
9. LAFATA, P., VODRAZKA, J. Application of passive optical network with optimized bus topology for local backbone data network. Microwave and Optical Technology Letters, 2011, vol. 53, no. 10, p. 2351-2355.
10. RUFFINI, M., PAYNE, D. B., DOYLE, L. Protection strategies for long-reach PON. In The 36th European Conference and Exhibition on Optical Communication (ECOC). Turin (Italy), 2010, p. 1-3.
11. KIM, Y. M., RYU, M. S., PARK, H. S. Novel redundancy design methodology for an optimal PON protection architecture. In Conference on Optical Fiber Communication and the National Fiber Optic Engineers Conference. Anaheim (USA), 2007. p. 1-3.
12. LAFATA, P. Protection of passive optical network by using ring topology. In The 35th International Conference on Telecommunications and Signal Processing (TSP). Prague (Czech Republic), 2012, p. 152-158.

Keywords: Asymmetric Optical Splitter, Passive Optical Network, Protection, Ring Topology

K. B. Baltzis [references] [full-text] [Download Citations]
Spatial Characterization of the Uplink Inter-Cell Interference in Polygonal-Shaped Wireless Networks

The uplink inter-cell interference is a major impairment in wireless systems. In this paper, we provide a geometrical-based framework for its analysis in networks with convex polygonal coverage area. Algebraic expressions for the Angle-of-Arrival (AoA) statistics of the uplink interfering signals are obtained. Simulation results validate the model. Representative examples show the dependence of the AoA on system geometry and demonstrate the relation between uplink interference and the radiation pattern of the receiver antenna. The proposed model is a generalization of previous studies in simpler geometries. It is a useful tool for the design, simulation and performance evaluation of wireless communication systems. The obtained expressions simplify the analysis of wireless networks and reduce the complexity and computational cost of their modeling and simulation.

1. BALTZIS, K. B. A geometrical-based model for cochannel interference analysis and capacity estimation of CDMA cellular systems. EURASIP Journal on Wireless Communications and Networking, 2008, 7 pages, doi: 10.1155/2008/791374.
2. SINGH, S., MEHTA, N. B., MOLISCH, A. F., MUKHOPADYHAY, A. Moment-matched lognormal modeling of uplink interference with power control and cell selection. IEEE Transactions on Wireless Communications, 2010, vol. 9, no. 3, p. 932 - 938.
3. GLEISSNER, F., HANUS, S. Co-channel and adjacent channel interference measurement of UMTS and GSM/EDGE systems in 900 MHz radio band. Radioengineering, 2008, vol. 17, no. 3, p. 74 to 80.
4. YUN, J.-H., SHIN, K. G. Adaptive interference management of OFDMA femtocells for co-channel deployment. IEEE Journal on Selected Areas in Communications, 2011, vol. 29, no. 6, p. 1225 to 1241.
5. PETRUS, P., ERTEL, R. B., REED, J. H. Capacity enhancement using adaptive arrays in an AMPS system. IEEE Transactions on Vehicular Technology, 1998, vol. 47, no. 3, p. 717 - 727.
6. GRANT, S. J., CAVERS, J. K. System-wide capacity increase for narrowband cellular systems through multiuser detection and base station diversity arrays. IEEE Transactions on Wireless Communications, 2004, vol. 3, no. 6, p. 2072 - 2082.
7. SOMEKH, O., ZAIDEL, B. M., SHAMAI, S. Sum rate characterization of joint multiple cell-site processing. IEEE Transactions on Information Theory, 2007, vol. 53, no. 12, p. 4473 - 4497.
8. BALTZIS, K. B., SAHALOS, J. N. A low–complexity 3-D geometric model for the description of CCI in cellular systems, Electrical Engineering (Archiv fur Elektrotechnik), 2009, vol. 91, no. 4, p. 211 - 219.
9. CHANDRASEKHAR, V., ANDREWS, J. G. Uplink capacity and interference avoidance for two-tier femtocell networks. IEEE Transactions on Wireless Communications, 2009, vol. 8, no. 7, p. 3498 - 3509.
10. BALTZIS, K. B., SAHALOS, J. N. On the statistical description of the AoA of the uplink interfering signals in a cellular communication system. European Transactions on Telecommunications, 2010, vol. 21, no. 2, p. 187 - 194.
11. XU, J., ZHANG, J., ANDREWS J. G. On the accuracy of the Wyner model in cellular networks. IEEE Transactions on Wireless Communications, 2011, vol. 10, no. 9, p. 3098 - 3109.
12. SAGONG, M, CHEUN, K. A statistical inter-cell interference model for uplink cellular OFDMA networks under log-normal shadowing and Rayleigh fading. IEEE Communications Letters, 2012, vol. 16, no. 6, p. 824 - 827.
13. DEMİR, M. A., OZEN, A. A novel variable step size adjustment method based on autocorrelation of error signal for the constant modulus blind equalization algorithm. Radioengineering, 2012, vol. 21, no. 1, p. 37 - 45.
14. NAWAZ, S. J., KHAN, N. M., PATWARY, M. N., MORINI, M. Effect of directional antenna on the Doppler spectrum in 3-D mobile radio propagation environment. IEEE Transactions on Vehicular Technology, 2011, vol. 60, no.7, p. 2895 - 2903.
15. BALTZIS, K. B. A simplified geometric channel model for mobile-to-mobile communications. Radioengineering, 2011, vol. 20, no. 4, p. 961 - 967.
16. OLENKO, A. Y., WONG, K. T., QASMI, S. A. Distribution of the uplink multipaths’ arrival delay and azimuth-elevation arrival angle because of ‘bad urban’ scatterers distributed cylindrically above the mobile. Transactions on Emerging Telecommunications Technologies, 2012, 20 pages, doi: 10.1002/ett.2530.
17. ZHANG, Z., WEI, S., YANG, J., ZHU, L. CIR performance analysis and optimization of a new mobile communication cellular configuration. In Proceedings of the 4th International Conference on Microwave and Millimeter Wave Technology. Beijing (China), 2004, p. 826 - 829.
18. ZHANG, Z., LEI, F., DU, H. More realistic analysis of co-channel interference in sectorization cellular communications systems with Rayleigh fading environments. In Proceedings of the 2nd International Conference on Wireless Communications, Networking and Mobile Computing. Wuhan (China), 2006, 5 pages, doi: 10.1109/WiCOM.2006.184.
19. XIAO, L., GREENSTEIN, L., MANDAYAM, N., PERIYALWAR, S. Distributed measurements for estimating and updating cellular system performance. IEEE Transactions on Communications, 2008, vol. 56, no.6, p. 991 - 998.
20. PIRINEN, P. Outage analysis of ultra-wideband system in lognormal multipath fading and square-shaped cellular configurations. EURASIP Journal on Wireless Communications and Networking, 2006, 10 pages, doi: 10.1155/wcn/2006/19460.
21. ZHUANG, Y., PAN, J., CAI, L. Minimizing energy consumption with probabilistic distance models in wireless sensor networks. In Proceedings of the 29th IEEE International Conference on Computer Communications. San Diego (USA), 2010, 9 pages, doi: 10.1109/INFCOM.2010.5462073.
22. ZHUANG, Y., PAN, J. A geometrical probability approach to location-critical network performance metrics. In Proceedings of the 31st IEEE International Conference on Computer Communications. Orlando (USA), 2012, p. 1817 - 1825.
23. BAI, X., KUMAR, S., XUAN, D., YUN, Z., LAI, T. H. Deploying wireless sensors to achieve both coverage and connectivity. In Proceedings of the 7th ACM International Symposium on Mobile Ad Hoc Networking and Computing. Florence (Italy), 2006, p. 131 to 142.
24. ISLAM, M. R. An issue of boundary value for velocity and training overhead using cooperative MIMO technique in wireless sensor network. Radioengineering, 2011, vol. 20, no. 2, p. 505 - 511.
25. MORAVEK, P., KOMOSNY, D., SIMEK, M., GIRBAU, D., LAZARO, A. Energy analysis of received signal strength localization in wireless sensor networks. Radioengineering, 2011, vol. 20, no. 4, p. 937 - 945.
26. SIMEK, M., MORAVEK, P., KOMOSNY, D., DUSIK, M. Distributed recognition of reference nodes for wireless sensor network localization. Radioengineering, 2012, vol. 21, no. 1, p. 89 to 98.
27. MELODIA, T., POMPILI, D., AKYILDIZ, I. F. Handling mobility in wireless sensor and actor networks. IEEE Transactions on Mobile Computing, 2010, vol. 9, no.2, p. 160 - 173.
28. NOORI, M., ARDAKANI, M. Lifetime analysis of random eventdriven clustered wireless sensor networks. IEEE Transactions on Mobile Computing, 2011, vol. 10, no.10, p. 1448 - 1458.
29. LI, W., MARTINS, P., SHEN, L. Determination method of optimal number of clusters for clustered wireless sensor networks. Wireless Communications and Mobile Computing, 2012, vol. 12, no. 2, p. 158 - 168.
30. MUAMMAR, R., GUPTA, S. Cochannel interference in highcapacity mobile radio channels. IEEE Transactions on Communications, 1982, vol. 30, no. 8, p. 1973 - 1978.
31. PRASAD, R., KEGEL, A. Improved assessment of interference limits in cellular radio performance. IEEE Transactions on Vehicular Technology, 1991, vol. 40, no. 2, p. 412 - 419.
32. AU, W. S., MURCH, R. D., LEA, C. T. Comparison between the spectral efficiency of SDMA systems and sectorized systems. Wireless Personal Communications, 2001, vol. 16, no. 1, p. 51 to 67.
33. PAPOULIS. A., PILLAI, S. U. Probability, Random Variables and Stochastic Processes. 4th ed. New York: McGraw-Hill, 2002.
34. LEE, J. S., MILLER, L. E. CDMA Systems Engineering Handbook. Boston: Artech House, 1998.
35. BALANIS, C. A. Antenna Theory. 3rd ed. Hoboken: Wiley, 2005.
36. NIEMELA, J., ISOTALO, T., LEMPIAINEN, J. Optimum antenna downtilt angles for macrocellular WCDMA network. EURASIP Journal on Wireless Communications and Networking, 2005, vol. 2005, no. 5, p. 816 - 827.
37. 3G TR 23.907 v1.2.0. Quality of Service (QoS) concept. DTS/TSGS-0223101U, 1999.
38. 3GPP TS 23.107 v11.0.0. Quality of Service (QoS) concept and architecture. RTS/TSGS-0223107vb00, rel. 11, 2012.
39. NIE, C., WONG, T. C., CHEW, Y. H. Outage analysis for multiconnection multiclass services in the uplink of wideband CDMA cellular mobile networks. In Proceedings of the 3rd IFIP-TC6 Networking Conference – Networking 2004. Athens (Greece), 2004, p. 1426 - 1432.
40. MALIK, W. Q., EDWARDS, D. J., STEVENS, C. J. Frequency dependence of fading statistics for ultrawideband systems. IEEE Transactions on Wireless Communications, 2007, vol. 6, no. 3, p. 800 - 804.
41. MALIK, W. Q. Spatial correlation in ultrawideband channels. IEEE Transactions on Wireless Communications, 2008, vol. 7, no. 2, p. 604 - 610.
42. PHAKASOUM, C., GHORAISHI, M., TAKADA, J.-I., KITAO, K., IMAI, T. Frequency characteristics of angular spread for radio wave propagation through foliage. In Proceedings of the 5th European Conference on Antennas and Propagation. Rome (Italy), 2011, p. 3289 - 3292.
43. PATZOLD, M., HOGSTAD, B. O. A wideband MIMO channel model derived from the geometric elliptical scattering model. Wireless Communications and Mobile Computing, 2008, vol. 8, no. 5, p. 597 - 605.
44. CHENG, X., WANG, C.-X., LAURENSON, D. I. A geometrybased stochastic model for wideband MIMO mobile-to-mobile channels. In Proceedings of the 2009 IEEE Global Telecommunications Conference. Honolulu (USA), 2009, 6 pages, doi: 10.1109/GLOVOM.2009.5425319.

Keywords: Angle-of-Arrival, polygon, interference, radiation pattern, geometric modeling, wireless networks

L. Xiao, Y. Yin, X.N. Wu, J. W. Wang [references] [full-text] [Download Citations]
A large-scale RF-based Indoor Localization System Using Low-complexity Gaussian filter and improved Bayesian inference

The growing convergence among mobile computing device and smart sensors boosts the development of ubiquitous computing and smart spaces, where localization is an essential part to realize the big vision. The general localization methods based on GPS and cellular techniques are not suitable for tracking numerous small size and limited power objects in the indoor case. In this paper, we propose and demonstrate a new localization method, this method is an easy-setup and cost-effective indoor localization system based on off-the-shelf active RFID technology. Our system is not only compatible with the future smart spaces and ubiquitous computing systems, but also suitable for large-scale indoor localization. The use of low-complexity Gaussian Filter (GF), Wheel Graph Model (WGM) and Probabilistic Localization Algorithm (PLA) make the proposed algorithm robust and suitable for large-scale indoor positioning from uncertainty, self-adjective to varying indoor environment. Using MATLAB simulation, we study the system performances, especially the dependence on a number of system and environment parameters, and their statistical properties. The simulation results prove that our proposed system is an accurate and cost-effective candidate for indoor localization.

1. Garmin Corporation, About GPS. [Online]. Available at: http://www.garmin.com/aboutGPS/.
2. HUI, L., HOUSHANG, D., PAT, B., JING, L. Survey of wireless indoor positioning techniques and systems. IEEE Transactions on Systems, Man, and Cybernetics- Part C, 2007, vol. 37, no. 6, p. 1067-1080.
3. HIGHTOWER, J., BORRIELLO, G. A survey and taxonomy of location sensing systems for ubiquitous computing. CSE 01-08-03, University of Washington, Department of Computer Science and Engineering, Seattle (USA). Technical Report, 2001.
4. GUOQIANG, M., BARIS, F., BRIAN, D. O. A. Wireless sensor network localization techniques. Computer Networks, 2007, vol. 51, no. 10, p. 2529–2553.
5. Radio Frequency Identification (RFID) home page. [Online]. Available at: http://www.aimglobal.org/technologies/rfid/.
6. YE, Y., JUN, Z., JIAN, Y. Design of World Expo tour sites guide system based on RFID technology. In Proceedings of 2010 International Conference on Audio Language and Image Processing (ICALIP 2010). Shanghai (China), 2010, p. 1026-1030.
7. HIGHTOWER, J., WANT, R., BORRIELLO, G. SpotON: An indoor 3d location sensing technology based on RF signal strength. UW-CSE 00-02-02, University of Washington, Department of Computer Science and Engineering, Seattle (USA). Thesis, 2000.
8. NI, L., LIU, Y., LAU, Y. C., PATIL, A. LANDMARC: Indoor location sensing using active RFID. In Proceedings of the 1st IEEE International Conference on Pervasive Computing and Communications(PERCOM’03). Dallas (USA), 2003, p. 407-415.
9. MAJA, S., MLADEN, R., DINKO, B. RF Localization in indoor environment. Radioengineering, 2012, vol. 21, no. 2, p. 557–567.
10. ZEPERNICK, H. J., WYSOCKI, T. A. Multipath channel parameters for the indoor radio at 2.4 GHz ISMband. In Proceedings of Vehicular Technology Conference, 1999 IEEE 49th . Houston (USA), 1999, vol. 1, p. 190-193.
11. ITO, K. Gaussian filter for nonlinear filtering problems. In Proceedings of the 39th IEEE Conference on Decision and Control. 2000, vol. 2, p. 1218-1223.
12. MINGHUI, Z., HUIQING, Z. Research on model of indoor distance measurement based on receiving signal strength. In Proc. of Internat. Conf. on Computer Design and Applications (ICCDA 2010). Qinhuangdao (China), 2010, vol. 5, p. 54-58.
13. RAPPAPORT, T. S. Wireless Communications Principles and Practices. Prentice-Hall Inc, 2002.
14. WOOYONG, L., KYEONG, H., TAEYOUNG, K., DOODEOP, E., JONGOK, K. Large scale indoor localization system based on wireless sensor networks for ubiquitous computing. Wireless Personal Communications, 2012, vol. 63, no. 1, p. 241-260.
15. MADIGAN, D., ELNAHRAWY, E., MARTIN, R. Bayesian indoor positioning systems. In Proceedings of 24th Annual Joint Conference of the IEEE Computer and Communications Societies (INFOCOM 2005). Miami (USA), 2005, vol. 2, p. 1217-1227.
16. CHRISTOPHER, M. B. Pattern Recognition and Machine Learning. New York: Springer-Verlag Inc, 2006.

Keywords: Indoor localization, Gaussian filter, wheel graph, probabilistic localization algorithm

Y. Wang, A. Liu, D. Guo, X. Liu [references] [full-text] [Download Citations]
Low-complexity Noncoherent Iterative CPM Demodulator for FH Communication

In this paper, we investigate the noncoherent iterative demodulation of coded continuous phase modulation (CPM) in frequency hopped (FH) systems. In this field, one important problem is that the complexity of the optimal demodulator is prohibitive unless the number of symbols per hop duration is very small. To solve this problem, we propose a novel demodulator, which reduces the complexity by applying phase quantization and exploiting the phase rotational invariance property of CPM signals. As shown by computational complexity analysis and numerical results, the proposed demodulator approaches the performance of the optimal demodulator, and provides considerable performance improvement over the existing solutions with the same computational complexity.

1. AULIN, T., SUNDBERG, C. E. Continuous phase modulation – parts I and II. IEEE Transactions on Communication, 1981, vol. 29, no. 3, p. 196-225
2. KIM, H., ZHAO, Q., STUBER, G. L., NARAYANAN, K. R. Antijamming performance of slow FH-CPM signals with concatenated coding and jamming estimation. In IEEE Military Communications Conference (MILCOM). Boston (MA, USA), 2003, vol. 2, p. 1120 - 1125.
3. NARAYANAN, K. R., STUBER, G. L. Performance of trellis-coded CPM with iterative demodulation and decoding. IEEE Transactions on Communications, 2001, vol. 49, no. 4, p. 676 - 687.
4. BROWN, C., VIGNERON, P. J. A reduced complexity iterative noncoherent CPM detector for frequency hopped wireless military communication systems. In IEEE Military Communications Conference (MILCOM). Atlantic City (NJ, USA), 2005, vol. 4, p. 2345 - 2349.
5. WANG, G., LI, Q., LI, S. Partial-band jamming suppression with a noncoherent CPM detector. In International Conference on Communications and Mobile Computing. Kunming (China), 2009, p. 204 - 208.
6. FRANZ, V., ANDERSON, J. B. Concatenated decoding with a reduced search BCJR algorithm. IEEE Journal on Selected Areas in Communications, 1998., vol. 16, no. 2, p. 186 - 195.
7. JACOBSEN, N., MADHOW, U. Coded noncoherent communication with amplitude/phase modulation: from Shannon theory to practical architectures.IEEE Transactions on Communications, Dec. 2008, vol. 56, no. 12, p. 2040 - 2049.
8. ZHAO, Q., KIM, H., STUBER, G. L. Innovations-based MAP estimation with application to phase synchronization for serially concatenated CPM. IEEE Transactions on Wireless Communications, 2006, vol. 5, no. 5, p. 1033 - 1043.
9. RIMOLDI, B. A decomposition approach to CPM. IEEE Transactions on Information Theory, 1988, vol. 34, no. 2, p. 260 - 270.
10. BENEDETTO, S., DIVSALAR, D., MONTORSI, G., POLLARA, F. A soft-input soft-output APP module for iterative decoding of concatenated codes. IEEE Communications Letters, 1997, vol. 1, no. 1, p. 22 - 24.
11. BENEDETTO, S., DIVSALAR, D., MONTORSI, G., POLLARA, F. Serial concatenation of interleaved codes: Performance analysis, design and iterative decoding. IEEE Transactions on Information Theory, 1998, vol. 44, no. 3, p. 909 - 926.
12. BAHL, L. R., COCKE, J., JELINEK, F., RAVIV, J. Optimal decoding of linear codes for minimizing symbol error rate. IEEE Transactions on Information Theory, 1974, vol. 20, no. 2, p. 284 - 287.
13. VALENTI, M., CHENG, S., TORRIERI, D. Iterative multisymbol noncoherent reception of coded CPFSK.IEEE Transactions on Communications, 2010, vol. 58, no. 7, p. 2046 - 2054.
14. GERTSMAN, M., LODGE, J. Symbol-by-symbol map demodulation of CPM and PSK signals on Rayleigh flat-fading channels.IEEE Transactions on Communications, 1997, vol. 47, no. 7, p. 788 - 799.
15. CHENG, S., VALENTI, M. C., TORRIERI, D. Coherent continuousphase frequency-shift keying: parameter optimization and code design. IEEE Transactions on Wireless Communications, 2009, vol. 8, no. 4, p. 1792 - 1802.

Keywords: Continuous phase modulation, frequency hopping, noncoherent demodulation, iterative demodulation, low-complexity.

I. Vertat, J. Mraz [references] [full-text] [Download Citations]
Hybrid M-FSK/DQPSK Modulations for CubeSat Picosatellites

Conventional CubeSat radio systems typically use one of several basic modulations, such as AFSK, GMSK, BPSK, QPSK and OOK or switch between them on demand if possible. These modulations represent a bal¬anced trade-off between good energy efficiency of high order M-FSK modulation and good spectral efficiency of high order M-QAM modulation. Utilization of modulations with the best energy efficiency is not possible due to strict limits on occupied frequency bandwidth. In this paper the proposed group of hybrid modulations and proposed hybrid modulator and demodulator are presented. Novel solution offer interesting possibilities of increasing spectral efficiency as well as energy efficiency of basic M-FSK modulation by embedding DQPSK symbols between two M-FSK symbols. Such group of hybrid modulations offers suitable properties for picosatellite, e.g. simple realization onboard the picosatellite, better energy and spectral efficiency, low PAPR, wide range of adaptation by changing the order of M-FSK, suitable for easy non-coherent demodulation, good immunity to Doppler effect with DM-FSK coding.

1. TAO, M. Principles of Communication: Chapter 8 - Digital modulation techniques [online]. Shanghai Jiao Tong University, 2012, p. 1-79.
2. WEI, L., KORN, I. Combined frequency and differential phase shift keying with non-coherent detection in satellite mobile channel. IEEE Trans. Veh. Tech., 1995, vol. 44, p. 603-612.
3. POKORNY, M. S-band conventional radio connection of the PilsenCUBE picosatellite. In 4th European CubeSat Symposium. Brussels (Belgium), 2012.
4. RUDY, L. Diploma Thesis. The performance of conventional and DBD receivers for MFSK/QPSK modulation when operating in the presence of noise and Rayleigh fading. Monterey, Naval Postgraduate School, 1988, p. 1-81.
5. LATIF, A. Doctoral Thesis. Hybrid QAM - FSK (HQFM) OFDM transceiver with low PAPR. Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, 2009, p. 1-144.
6. DIGHAM, F., ALOUINI, M. Spectrally efficient hybrid FSK/QAM with optimum bit and power loading. In Proc. IEEE International Conference on Communications (ICC’06). 2006, vol. 11, p. 5022-5027.
7. Dream DRM Receiver: A software Digital Radio Mondiale (DRM) receiver [online]. Available at: http://sourceforge.net/projects/drm/
8. EGNOR, D., et al. Differential frequency hopping (DFH) modulation for underwater mobile ad-hoc networks. U.S. Navy Journal of Underwater Acoustics, 2011.
9. KOVAR, J., KASAL, M. Automatic compensation of Doppler shift in communication with satellites on non-geostationary Earth orbit. Elektrorevue, 2008, p. 1-8. (In Czech).
10. VERTAT, I. Doctoral Thesis. Effective Communication System for Picosatellites. University of West Bohemia in Pilsen, Faculty of Electrical Engineering, 2011, 128 p. (In Gzech).
11. VERTAT, I., LINHART, R., POKORNY, M., KAVALIR, T. Signal quality evaluation for picosatellite communication system. In International Conference on Applied Electronics 2012. Pilsen (Czech Rep.), 2012. ISBN: 978-80-261-0038-6
12. KAVALIR, T. PilsenCUBE ground station. In 4th European CubeSat Symposium. Brussels (Belgium), 2012.
13. KLOFAS, B., ANDERSON, J. A survey of CubeSat communication subsystem. In 5th Annual CubeSat Workshop. California Polytechnic University, 2008, p. 1-36.

Keywords: CubeSat, picosatellite communication system, adaptable modulation, hybrid modulation.

J. R. O. Fernandez, D. Draskovic, C. Briso–Rodriguez [references] [full-text] [Download Citations]
High–Speed Data Transmission Subsystem of the SEOSAR/PAZ Satellite

This paper analyzes a digital interface and bus system modeling and optimization of the SEOSAR/PAZ Earth Observation satellite. The important part of the satellite is an X–band Synthetic Aperture Radar instrument that integrates 384 Transmit/Receive Modules located in 12 antenna panels 7.5 m away from the central processor and controlled by a synchronous 10 Mbps bidirectional serial protocol. This type of mid–range point–to–multipoint transmission is affected by bit errors due to crosstalk, transmission line attenuation and impedance mismatches. The high–speed data communication network has been designed to optimize the transmission by using a simulation model of the data distribution system which takes into account the worst–case scenario and by developing a lab–scaled prototype which exhibits BER of 10-11 for an interfering signal of 10 Vpp. The result is a point–to–multipoint bidirectional transmission network optimized in both directions with optimal values of loads and equalization resistors. This high–speed data transmission subsystem provides a compact design through a simple solution.

1. ROSTAN, F., et al. CryoSat prelaunch status and performance. In Proceedings of the IEEE Geoscience and Remote Sensing Symposium, 2005, p. 456-459.
2. GIUDICI, D., et al. Roll-steering for improving SAOCOM-SAR performances. In Proceedings of the IEEE Radar Conference, 2010, p. 752-755.
3. CALTAGIRONE, F. Status, results and perspectives of the Italian Earth Observation SAR COSMO – SkyMed. In Proceedings of the IEEE European Radar Conference, 2009, p. 330-334.
4. SANCHEZ PALMA, J., et al. SAR Panel Design and Performance for the PAZ Mission. In Proceedings of the IEEE European Conference on Synthetic Aperture Radar, 2010, p. 1-4.
5. MONJAS, F., et al. X–band SAR Antenna for SEOSAR/PAZ Satellite. In Proceedings of the ESA Antenna Workshop on Antennas for Space Applications. 2010.
6. WILSON, M. R. TIA/EIA–422–B Overview. National Semiconductor, Application Note 1031, 2000.
7. AWR Design Environment. Version 2009.
8. FINK, D. G., BEATY, H. W. Standard Handbook for Electrical Engineers. McGraw-Hill, Eleventh Edition, ISBN 0-07-020974-X, p. 4-18 and table 4-11, 1978.
9. http://www.engineering.mq.edu.au/research/groups/cnerf/resources /MWO_AO_2004Elements.pdf, page 1340-1342.
10. WEI-YU, C., et al. Analytical models for crosstalk excitation and propagation in VLSI circuits. IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, 2002, vol. 21, p. 1117-1131.
11. HEYDARI, P., M. PEDRAM, M. Capacitive coupling noise in high-speed VLSI circuits. IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, 2005, vol. 24, p. 478-488.
12. VO, J. A Comparison of Differential Termination Techniques. National Semiconductor, Application Note 903, 1993.

Keywords: Crosstalk, data buses, high–speed communications, SAR, satellite, SEOSAR/PAZ

S. Phrompichai [references] [full-text] [Download Citations]
SGD Frequency-Domain Space-Frequency Semiblind Multiuser Receiver with an Adaptive Optimal Mixing Parameter

A novel stochastic gradient descent frequency-domain (FD) space-frequency (SF) semiblind multiuser receiver with an adaptive optimal mixing parameter is proposed to improve performance of FD semiblind multiuser receivers with a fixed mixing parameters and reduces computational complexity of suboptimal FD semiblind multiuser receivers in SFBC downlink MIMO MC-CDMA systems where various numbers of users exist. The receiver exploits an adaptive mixing parameter to mix information ratio between the training-based mode and the blind-based mode. Analytical results prove that the optimal mixing parameter value relies on power and number of active loaded users existing in the system. Computer simulation results show that when the mixing parameter is adapted closely to the optimal mixing parameter value, the performance of the receiver outperforms existing FD SF adaptive step-size (AS) LMS semiblind based with a fixed mixing parameter and conventional FD SF AS-LMS training-based multiuser receivers in the MSE, SER and signal to interference plus noise ratio in both static and dynamic environments.

1. OJANPERA, T., PRASAD, R. An overview of air interface multiple access for IMT-2000/UMTS. IEEE Communications Magazine, 1998, vol. 36, no. 9, p. 82-86, 91-95.
2. ADACHI, F., SAWAHASHI, M., SUDA, H. Wideband DSCDMA for next-generation mobile communication systems. IEEE Communication Magazine, 1998, vol. 36, p. 56-69.
3. YEE, N., LINNARTZ, J.-P., FETTWEIS, G. Multicarrier CDMA in indoor wireless radio network. In Proceedings of the Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications PIMRC 1993. Yokohama (Japan), 1993, p. 109-113.
4. PLASS, S., KAISER, S. MC-CMDA versus OFDMA in cellular environments. In Proceeding European Signal Processing Conference (EUSIPCO’2005). Antalya (Turkey), 2005, p. 1-4.
5. CHOULY, A., BRAJAL, A., JOURDAN, S. Orthogonal multicarrier techniques applied to direct sequence spread spectrum CDMA systems. In Proceedings of IEEE GLOBECOM. 1993, vol. 3, p. 1723-1728.
6. YANG-SEOK CHOI, VOLTZ, P. J., CASSARA, F. A. On channel estimation and detection for multicarrier signals in fast and selective Rayleigh fading channels. IEEE Transaction on Signal Communication, 2001, vol. 49, p. 1375-1387.
7. XIAODONG CAI, GIANNKIS, G. B. Low complexity ICI suppression for OFDM over time and frequency-selective Rayleigh fading channels. In Proceeding of Asilomar Conference on Signals, Systems and Computers. 2002, p. 1822-1826.
8. ALAMOUTI, S. M. A simple transmit diversity technique for wireless communications mobile system. Journal on Selected Areas in Communication, 1998, vol. 16, no. 8, p. 1451-1458.
9. ZEXIAN LI, LATVA-AHO, M. Performance of space-time block coded MC-CDMA in Nakagami fading channel. Electronic Letters, 2003, vol. 39, p. 222-224.
10. XIAOYU HU, YONG-HUAT CHEW On the performance and capacity of an asynchronous space-time block-code MC-CDMA system in the present of carrier frequency offset. IEEE Transactions on Vehicular Technology, 2004, vol. 53, no. 5, p. 1327-1340.
11. KAFLE, P. L., SESAY, A. B. Iterative semiblind multiuser receivers for space-time block-coded MC-CDMA uplink system. IEEE Transactions on Vehicular Technology, 2004, vol. 53, no. 5, p. 601-610.
12. LINDSKOG, E., PAULRAJ, A. A transmit diversity scheme for channels with intersymbol interference. In Proceeding of the International Conference on Communication ICC 2000. New Orleans (USA), June 2000, vol. 1, p. 307-311.
13. DEHGHANI, M. J., ARAVIND, R., JAM, S., PRABHU, K. M. Space-frequency block coding in OFDM systems. In Proceeding IEEE TENCON. 2004, vol. 1, p. 543-546.
14. XIAOJUN WU, QINYE YIN, HANGUO ZHANG, KE DENG Time-domain multiuser detection for MC-CDMA systems without cyclic prefix. In Proceedings of IEEE International Conference on Communication ICC 2002. New York (USA), 2002, p. 921-925.
15. WEISS, A. J., FRIEDLANDER, B. Channel estimation for DSCDMA downlink with aperiodic spreading codes. IEEE Transactions on Communication, 1999, vol. 47, no. 10, p. 1561-1569.
16. PUNNOOSE, S., ZHU XU, NANDI, A. K. Blind channel estimation for MIMO uplink single carrier CDMA block transmission systems. In Proceedings of the 18th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications PIMRC’2007. Athens (Greece), 2007, p. 1-5.
17. 3GPP/3GPP2 25.996 v6.1.0 (2003-09). Spatial channel model for multiple input multiple output (MIMO) simulations (Release6). Available at: http://www.quintillion.co.jp/3GPP/Specs; in 3Gpp, Spatial Channel.
18. ZHIGUO DING, WARD, D. B. Semi-blind equalization for space time block codes and its ambiguity analysis. In Proceeding of IEEE International Conference on Communication ICC 2004. Paris (France), 2004, p. 2357-2361.
19. AKTAS, E., MITRA, U. Semiblind channel estimation for CDMA systems with parallel data and pilot signals. IEEE Transaction on Communication, 2004, vol. 52, no. 7, p. 1102-1112.
20. ZHIGUO DING, WARD, D. B. Direct semi-blind MMSE equalization for STBC. IEEE Signal Processing Letters, 2005, vol. 12, no. 5, p. 380-383.
21. MOON, T. K. The expectation-maximization algorithm. IEEE Signal Processing Magazine, 1996, vol. 13, p. 46-60.
22. ZEXIAN LI, LATVA-AHO, M. Nonblind and semiblind spacefrequency multiuser detection for multirate MC-CDMA systems. IEEE Transactions on Signal Processing, 2006, vol. 54, no. 11, p. 4393-4404.
23. MURTHY, CH. R., JAGANNATHAM, A. K., RAO, B. D. Training-base and semiblind channel estimation for MIMO systems with maximum ratio transmission. IEEE Transactions on Signal Processing, 2006, vol. 54, no. 7, p. 2546-2558.
24. SHYNK, J. J. Frequency-domain and multirate adaptive filtering. IEEE Signal Processing Magazine, 1992, vol. 9, no. 1, p. 14-37.
25. ZHENG, Y. R.., CHENGSHAN XIAO Channel estimation for frequency-domain equalization of single-carrier broadband wireless communications. IEEE Transactions on Vehicular Technology, 2009, vol. 58, no. 5, p. 815-823.
26. LAI-U CHOI, MURCH, R. D. A transmit MIMO scheme with frequency domain pre-equalization for wireless frequency selective channels. IEEE Transactions on Wireless Communication, 2004, vol. 3, no. 3, p. 929-938.
27. COON, J., ARMOUR, S., BEACH, M., MCGEEHAN, J. Adaptive frequency-domain equalization for single-carrier multiple-input multiple-output wireless transmissions. IEEE Transactions on Signal Processing, 2005, vol. 53, no. 8, p. 3247-3256.
28. QING ZHAO, ZHONGPEI ZHANG, ZHIPING SHI Research and link simulation of key technologies for LTE. In Proceeding of the 6 th International Conference on Wireless Communications, Networking, and Mobile Computing WiCOM’2010. Chengdu (China), 2010, p. 1-4.
29. PETRE, F., LEUS, G., DENEIRE, L., ENGELS, M., MOONEN, M., DE MAN, H. Space-time block coding for single-carrier block transmission DS-CDMA downlink. IEEE Journal on Selected Areas in Communication, 2003, vol. 21, no. 3, p. 350-361.
30. HUI LU, QIXING WANG, YONGYU CHANG, DACHENG YANG SVD-based frequency domain equalizer for MIMO-CDMA systems using virtual antenna. In Proceeding of the 67th Vehicular Technology Conference IEEE-VTC’2008. Singapore, 2008, p. 1-5.
31. YANG HU, ASTELY, D., BALDEMAIR, R., FALAHATI, S. Semi-blind multiuser detection for LTE PUCCH. In Proceeding of the IEEE Wireless Communication and Networking Conference WCNC 2009. Budapest (Hungary), 2009, p. 1-5.
32. BANGWON SEO, WOO-GEUN AHN, CHEOL JEONG, HYUNG-MYUNG KIM Fast convergent LMS adaptive receiver for MC-CDMA systems with space-time block coding. IEEE Communications Letters, 2010, vol. 14, no. 8, p. 737-739.
33. LIJUN SUN, XIANGLI WANG, SHOUYONG ZHANG. A novel frequency domain equalization algorithm for SC-FDE system. In Proceeding of Pacific-Asia Conference on Knowledge Engineering and Software Engineering KESE’09. Shenzhen (China), 2009, p. 132-135.
34. MASUD RANA, MD., KIM, J., CHO, W. K. LMS based adaptive channel estimation for LTE uplink. Radioengineering, 2010, vol. 19, no. 4, p. 678-688.
35. VAN ACKER, K., LEUS, G., MOONEN, M., VAN DE WIEL, O., POLLET, T. Per tone equalizer for DMT-based systems. IEEE Transactions on Communications, 2001, vol. 49, no. 1, p. 109 to 119.
36. YUVAPOOSITANON, P., PHROMPICHAI, S., CHAMBER, J. A. An adaptive step-size LMS chip equalizer for long-code downlink CDMA. In Proceeding ECTI’ 2003, 2003, p. 210-213.
37. KRISHNAMURTHY, V., YIN, G., SINGH, S. Adaptive step-size algorithms for blind interference suppression in DS/CDMA systems. IEEE Transactions on Signal Processing, 2001, vol. 49, no. 1, p. 190-201.
38. KNUTH, D. E. The Art of Computer Programming. 2nd ed. Addison-Wesley Publish Company, 1981.
39. IEEE802.20 working group on mobile broadband wireless access channel models for IEEE 802.20 MBWA systems. Available at: http://www.ieee802.org/20/Contribs/C802.20-03-70.pdf.
40. KERMOAL, J. P., K., SCHUMACHER, L., PEDERSEN, K. I., MOGENSEN, P. E., FREDERIKSEN, F. A stochastic MIMO radio channel model with experimental validation. IEEE Journal on Selected Areas in Communications, 2002, vol. 20, no. 6, p. 1211-1226.

Keywords: SGD, semiblind, SFBC, MIMO, MC-CDMA, Adaptive Step-size