Iterative multiple-symbol differential detection of differential LDPC codes

In this paper, an iterative multiple-symbol differential detection (MSDD) scheme for differential LDPC codes is considered over slow and fast Rayleigh fading channels. The metric computation algorithm and its simplified algorithm used to output soft information for MSDD are derived. Simulation results demonstrate that the bit error rate (BER) performance of the proposed system is close to that of coherent detection by extending the observation interval and iterative decoding. In addition, the simulation results show that the proposed system, which can exploit the time diversity benefit of the fast fading channels, has much better performance over fast fading channels.