Reduced Complexity Combined Soft-Decision MLSE Equalization and Decoding

A maximum likelihood sequence estimation (MLSE) combined equalizer and decoder with soft-decision decoding performance, that has a computational complexity superior to that of conventional MLSE equalization, is proposed. Its performance is compared to a system containing a soft-output Viterbi MLSE equalizer followed by a soft-decision Viterbi MLSE decoder. It is shown via computer simulation that the proposed algorithm's performance matches that of conventional soft-decision decoding, while eliminating the use of a decoder in the receiver, for frequency-selective Rayleigh fading channels.