Bandwidth optimization for combined equalization and coding transceivers with emphasis on the MMSE-DFE

The problem of optimizing the transmission bandwidth of practical coded-modulation transceivers on linear time-invariant (LTI) dispersive channels corrupted by additive white Gaussian noise (AWGN) and crosstalk, with particular emphasis on digital subscriber loops, is studied. Under the assumption of a flat input power distribution over the transmission bandwidth, four criteria for bandwidth optimization are analyzed and compared. The main focus is on the ideal infinite-length minimum-mean-square error decision feedback equalizer (MMSE-DFE), however, finite-length constraints are also considered. Furthermore, comparisons between the optimal bandwidth and performance of the MMSE-DFE and a multichannel modulation (MCM) transceiver, under a variety of operating conditions, are presented