On the Performance of LDPC Codes with Differential Detection over Rayleigh Fading Channels

In this paper, the performance of low-density parity-check (LDPC) codes with differential detection is studied over additive white Gaussian noise (AWGN) and Rayleigh fading channels with particular emphasis on the sensitivity of signal-to-noise ratio (SNR) parameters required for metric calculation. Two simple metrics are derived and compared. Computer simulation results demonstrate that an SNR mismatch has a considerable effect on the performance of LDPC codes, and optimal SNR mismatches are explored in terms of bit error rate performances. It is shown that in some cases a pessimistic SNR estimation can improve the overall performance