Research on Decoding Algorithm for LDPC-COFDM Wireless Communication System

In this paper, the LDPC-COFDM wireless communication system with MQAM and its decoding algorithm are studied. An effective algorithm is proposed, which is based on hard-decision for some specially received symbols far away from normal symbols on the constellation. Then according to the distance between received symbols and decoded symbols, the pseudo Log-Likelihood-Ratio(LLR) is calculated, and taken as the pseudo initialization information for the next iteration. Simulation results indicate that this system is of good performance in the multipath channel model and the algorithm is effective.