Symbol Rate Optimization for the MMSE-DFE on Bandlimited Dispersive Channels

Al-Dhahir, N., and Cioffi, J. M., Symbol Rate Optimization for the MMSE-DFE on Bandlimited Dispersive Channels,Digital Signal Processing6 (1996), 73–95. The problem of optimizing the transmission bandwidth of practical coded-modulation transceivers on linear time-invariant dispersive channels corrupted by additive white Gaussian noise and crosstalk, with particular emphasis on digital subscriber loops, is studied in this paper. Under the assumption of a flat input power distribution over the transmission bandwidth, four criteria for bandwidth optimization are analyzed and compared. Our main focus will be on the ideal infinite-length minimum-mean-square-error decision-feedback equalizer (MMSE-DFE); however, finite-length constraints in addition to zero-forcing and linear equalizers are also considered. Furthermore, comparisons between the optimal bandwidth and performance of the MMSE-DFE and a multichannel modulation transceiver, under a variety of operating conditions, are also presented.