Further results on receivers for the nonlinear channel including pre- and post-nonlinearity filtering

The authors extend previous results (Dubey and Taylor, 1986) on an optimum receiver structure for receiving quaternary phase-shift keyed signals over a digital satellite communications channel, to include the effects of filtering following the nonlinear satellite transponder. The error performance of the receiver at low signal-to-noise ratios (SNR) is evaluated by computer simulation. An upper bound on the probability of symbol error at moderate to high SNR is also obtained. Finally, a suboptimum receiver is developed, and its performance evaluated using computer simulation. The degradation in performance of the suboptimum receiver, compared to the optimum receiver, is small