A new decision-feedback/linear-prediction receiver for digital modulation in fading channels

A new decision-feedback/linear-prediction receiver for coherent differentially encoded phase shift keying (DPSK) over Rayleigh flat-fading channel is presented. This receiver uses the previously detected symbols to estimate the previous channel gains and predict the current channel gain continuously, and therefore makes the optimal coherent detection of DPSK symbol-by-symbol. The receiver has a simple structure and can be implemented easily. This is due partly to the fact that the linear predictors used for channel estimation do not depend on the autocorrelation function of the fading process. Simulation results on the bit error performance of QDPSK with the new receiver are given for Rayleigh flat-fading channels. The results show that the proposed receiver can provide a reasonably good BER performance in a fast Rayleigh fading channel