Minimum intersymbol interference methods for time domain equalizer design

During initialization, discrete multitone receivers train a time domain equalizer (TEQ) to shorten the channel impulse response to a preset length, /spl nu/+1. G. Arslan et al. report a minimum intersymbol interference (Min-ISI) method for TEQ design (see IEEE Trans. Sig. Process., vol.49, no.12, p.3123-35, 2001). Min-ISI TEQs give the highest bit rates among single-FIR TEQs amenable to real-time implementation on programmable fixed-point digital signal processors (DSPs). The Min-ISI method, however, has several disadvantages: (1) sensitivity to transmission delay; (2) inability to design TEQs longer than /spl nu/+1 taps; (3) sensitivity to the fixed-point computation in the Cholesky decomposition. We develop an alternate Min-ISI cost function, from which we derive: (1) a fast search method for the optimal transmission delay; (2) extensions to design arbitrary-length Min-ISI TEQs; (3) an iterative Min-ISI method. The iterative Min-ISI method avoids Cholesky decomposition, designs arbitrary length TEQs, and achieves the bit rate performance of the original Min-ISI method.

[1]  T. Moon,et al.  Mathematical Methods and Algorithms for Signal Processing , 1999 .

[2]  P. P. Vaidyanathan,et al.  Noise optimized eigenfilter design of time-domain equalizers for DMT systems , 2002, 2002 IEEE International Conference on Communications. Conference Proceedings. ICC 2002 (Cat. No.02CH37333).

[3]  John M. Cioffi,et al.  A Discrete Multitone Transceiver System for HDSL Applications , 1991, IEEE J. Sel. Areas Commun..

[4]  Ming Ding,et al.  Infinite length results for channel shortening equalizers , 2003, 2003 4th IEEE Workshop on Signal Processing Advances in Wireless Communications - SPAWC 2003 (IEEE Cat. No.03EX689).

[5]  Charles E. Rohrs,et al.  Impulse response shortening for discrete multitone transceivers , 1996, IEEE Trans. Commun..

[6]  Brian L. Evans,et al.  Equalization for discrete multitone transceivers to maximize bit rate , 2001, IEEE Trans. Signal Process..

[7]  Behrouz Farhang-Boroujeny,et al.  Design methods for time-domain equalizers in DMT transceivers , 2001, IEEE Trans. Commun..

[8]  B.L. Evans,et al.  DMT bit rate maximization with optimal time domain equalizer filter bank architecture , 2002, Conference Record of the Thirty-Sixth Asilomar Conference on Signals, Systems and Computers, 2002..

[9]  Changchuan Yin,et al.  Optimal impulse response shortening for discrete multitone transceivers , 1998 .

[10]  Marc Moonen,et al.  Per tone equalization for DMT-based systems , 2001, IEEE Trans. Commun..

[11]  D. D. Falconer,et al.  Adaptive channel memory truncation for maximum likelihood sequence estimation , 1973 .

[12]  Joachim Speidel,et al.  An efficient equalization method to minimize delay spread in OFDM/DMT systems , 2001, ICC 2001. IEEE International Conference on Communications. Conference Record (Cat. No.01CH37240).

[13]  N. Al-Dhahir,et al.  Efficiently computed reduced-parameter input-aided MMSE equalizers for ML detection: a unified approach , 1996, IEEE Trans. Inf. Theory.

[14]  C. Richard Johnson,et al.  Exploiting symmetry in channel shortening equalizers , 2003, 2003 IEEE International Conference on Acoustics, Speech, and Signal Processing, 2003. Proceedings. (ICASSP '03)..

[15]  William A. Sethares,et al.  A blind adaptive TEQ for multicarrier systems , 2002, IEEE Signal Processing Letters.

[16]  John M. Cioffi,et al.  Equalizer training algorithms for multicarrier modulation systems , 1993, Proceedings of ICC '93 - IEEE International Conference on Communications.

[17]  Ming Ding,et al.  A dual-path TEQ structure for DMT-ADSL systems , 2002, 2002 IEEE International Conference on Acoustics, Speech, and Signal Processing.