Near-optimal low complexity joint estimation of cochannel ISI signals for mobile receivers

Cochannel interference affects not only the signal quality, but also the capacity of most wireless cellular networks. Unlike in spread spectrum communications, in systems employing nonspread signals, cochannel signal suppression is expensive. Moreover, at the portable station, joint estimation rather than suppression of the cochannel signal(s) may be a cheaper alternative and may often-times also provide a better signal quality. In this work we propose a novel two-stage joint Viterbi algorithm with full feedback. This technique, which is sub-optimal to the ideal joint maximum likelihood sequence estimator, provides an excellent way to trade complexity for performance, and is amenable for single-input mobile and hand-held receiver implementations