In this paper, the performance of the LDPC coded MIMO system scheme is evaluated through numerical simulations, and according to the belief propagation decoding algorithm of LDPC codes, a combined iterative detection/decoding MAP algorithm based on the factor-graph representation is proposed. The system performance is analyzed under two transmitter encoding structures, namely the separate encoding structure and the combined encoding structure respectively. Simulation results show that LDPC codes can increase the effective diversity gain by utilizing both the space and the time diversity effects of the MIMO system, and the combined iterative detection/decoding algorithm results in different performance gain for the two transmitter encoding structures.
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