DOI QR코드

DOI QR Code

다중 스텝 크기 LMS를 이용한 MSAGF-MMA 적응 블라인드 등화의 성능 개선

Performance Improvement of MSAGF-MMA Adaptive Blind Equalization Using Multiple Step-Size LMS

  • 정영화 (남서울대학교 정보통신공학과)
  • 투고 : 2013.06.19
  • 심사 : 2013.08.16
  • 발행 : 2013.08.31

초록

적응 블라인드 등화는 고속 디지털 데이터 전송시 통신 채널에서 발생되는 부호간 간섭을 최소화하는데 사용되고 있는 기법이다. 본 논문에서는 기존의 MSAGF-MMA 적응 블라인드 등화 알고리즘에 다중 스텝 크기 LMS를 적용함으로써 MSAGF-MMA 알고리즘의 성능을 더욱 개선시킨 등화 알고리즘을 제안한다. 이 알고리즘은 결정지향 크기 오차의 범위를 여러 개로 나누어 각각의 범위에 따라 스텝 크기를 달리 적용하는 다중 스텝 크기를 가지는 LMS 알고리즘을 MSAGF-MMA에 적용하였다. 컴퓨터 모의실험을 통하여 제안한 알고리즘이 MMA나 MSAGF-MMA에 비해 수렴 속도 면에서나 정상상태에서의 잔류 심볼간 간섭 및 잔류 오차, 그리고 앙상블 평균 MSE등에서 크게 향상된 성능을 가짐을 확인하였다.

An adaptive blind equalization is a technique using to minimize the Inter-symbol Interference occurred on a communication channel in the transmission of the high speed digital data. In this paper, we propose a blind equalization more improving performance of the conventional MSAGF-MMA adaptive blind equalization algorithm by applying a multiple step size. This algorithm apply a LMS algorithm with a several step size according to each region divided by absolute values of decision-directed error to MSAGF-MMA. By computer simulation, it is confirmed that the proposed algorithm has a performance highly enhanced in terms of a convergence speed, a residual ISI and a residual error and an ensemble averaged MSE in a steady status compared with MMA and MSAGF-MMA.

키워드

참고문헌

  1. Y. Sato, "A Method of Self-Recovering Equalization for Multilevel Amplitude-Modulation System," IEEE Trans, Commun., vol. COM-23, pp. 679-682, Jun. 1975.
  2. D.N.Golard, "Self-Recovering Equalization and Carrier Tracking in Two-Dimensional Data Comm. Systems," IEEE Trans, Commun., vol.COM-28, no. 11, pp. 1867-1875, Nov. 1980.
  3. K.N. Oh and Y.O. Chin, "Modified Constant Modulus Algorithm: Blind Equalization and Carrier Phase Recovery Algorithm," Proc. 1995 EEE Int. Conf. Commun., Seattle, WA, vol. 1, pp. 498-502, June. 1995.
  4. J. Yang, J.-J. Werner and G. A. Dumont, " The Multimodulus Blind Equalization algorithm," in Proc. Int. Conf Digital Signal Processing, vol. 1, pp. 127-130, July 1997. https://doi.org/10.1109/ICDSP.1997.627988
  5. J. Yang, J.-J. Werner, and G.A. Dumont, "The Multimodulus Blind Equalization and its Generalized Algorithms," IEEE J. Selected Areas Commum., vol. 20, no. 5, June 2002, pp. 997-1015. https://doi.org/10.1109/JSAC.2002.1007381
  6. V. Weerackody and S. A. Kassam, ''Dual-mode type algorithm for blind equalization," IEEE Trans. Commun., vol. COM-42, pp.22-28, Jan. 1994.
  7. R. A. Axford Jr., L. B. Milstein, and J.R. Zeidler, "A Dual-Mode Algorithm for Blind Equalization of QAM Signals: CADAMA," Proc. Asilomar-29, vol.1, pp. 172-176. 1996.
  8. L. M Garth, J. Yang, and J.-J. Werner, "Blind Equalizations for Dual-Mode CAP-QAM Reception," IEEE Trans, Commun., vol. 49, no. 3, Mar. 2001, pp.455-466. https://doi.org/10.1109/26.911453
  9. K.C. Hung, D. W. Lin, and C.N. Ke, "Variable-step -size multimodulus blind decision-feedback equalization for high-order QAM based on boundary MSE estimation," in Proc. IEEE int. Conf. Acoust. Speech Signal Processing, vol. 4, pp. 881-884, May 2004.
  10. K.-C Hung, D. W. Lin, "A Hybrid Variable Step-Size Adaptive Blind Equalization Algorithm for QAM Signals," in IEEE GLOBECOM 2005 proceedings., vol. 4, pp. 2140-2144, Dec. 2005.
  11. D. Ashmawy, K. Banovic, E. Abdel-Raheem, M. Youssif, H. Mansour, M. Mohanna,"Joint MCMA and DD blind equalization algorithm with variable-step size," Proceedings of 2009 IEEE I International Conference on Electro/Information Technology, pp. 174-177, June. 2009.
  12. Y.H Jeong, "A New Blind Equalization Algorithm with A Stop-and_Go Flag," The Journal of Information Technology, KIITI, vol.8, No.3, pp.105-115, Sep. 2005.
  13. O. Shalvi and E. Weinstein, "New Criteria for Blind Deconvolution of Nonminimum Phase Systems (Channels)," IEEE Trans. Inform. Theory, pp.313-320, March 1990.
  14. J.R Treichler and B.G.Agee, "A new approach to multipath correction of constant modulus signals," IEEE Trans. Acoust., Speech, Signal Processing, vol. ASSP-31, pp.459-472, Apr.1983.
  15. Z. Ding, et. al., "Ill-Convergence of Godard Blind Equalizers in Data Communication Systems." IEEE Trans. Commun., vol. 39, no.9, pp.1313-1326, Sep, 1991. https://doi.org/10.1109/26.99137
  16. G. Picchi and G. Prati, "Blind Equalization and Carrier Recovery Using a "Stop-and-Go" Decision-Directed Algorithm," IEEE Trans. Commun., vol. COM-35, no.9, pp. 877-887, Sep. 1987.