LDPC Codes with BDPSK and Differential Detection Over Flat Rayleigh Fading Channels

Abstract

We derive the correct log-likelihood differential detection metric for iterative decoding of LDPC codes transmitted with BDPSK modulation over Rayleigh fading channels. This metric does not require estimation of the amplitudes of the complex channel gains, showing that existing metrics in the literature that require estimation of amplitudes of channel gains are suboptimum. Simulation results confirm that an intentional SNR underestimation further improves BEP.