Prediction-based decision-feedback differential detection for MDPSK

In this paper, a decision-feedback differential detection (DF-DD) scheme for M-ary differential phase-shift keying (MDPSK) signals transmitted over Ricean fading channels is proposed. This scheme can improve conventional differential detection (DD) significantly for a multitude of frequency-nonselective channels. Moreover, prediction-based DF-DD is particularly well suited for application in mobile communications since the predictor coefficients may be updated regularly using the recursive least-squares (RLS) algorithm. Here, adaptation can start blind, i.e., no training sequence and no a priori knowledge about the channel statistics are required. A further important characteristic of the proposed detection scheme is that no degradation occurs under frequency offset