A Maximum-Likelihood Sequence Estimator with Decision-Feedback Equalization

Abstract

Absfruct-A decision-feedback equalizer (DFE) is proposed as a prefilter which limits the complexity of a maximum-likelihood sequence estimator (MLSE) implemented by the Viterbi algorithm (VA) for channels having a long impulse response. By imbedding a DFE into the structure of the MLSE, the overall impulse response of the system is truncated to a short duration. With this practical receiver, a compro-* F. S. Hill, Jr. (M'67-SM'76), for a photograph and biography, see page 354 of the March 1977 issue of this TRANSACTIONS.