LDPC-based Distributed Space Time Cooperative Systems with Non-regenerative Relays

The concatenation scheme of Low-density parity- check (LDPC) codes and space-time block coding (LDPC-STBC) has been proved to be effective in the multiple-input multi- ple-output (MIMO) system. In this paper, we extend the LDPC-STBC to the distributed wireless network with one and two non-regenerative relays. LDPC-based distributed space time cooperative (LDPC-DSTC) systems are proposed, and the decod- ing algorithms are discussed. The performance of the proposed systems is examined in different configurations. Simulation re- sults show that the LDPC-DSTC systems can reduce the trans- mission error and offer the diversity gain. The location of the relays has a profound effect on the system performance. � the destination are discussed. We examine the performance of the proposed systems in different configurations. Simulation results show that the LDPC-DSTC systems can reduce the bit error rate and offer the diversity gain. Simulation results also indicate that the location of the relays has profound impact on the performance. The remainder of this paper is organized as follows. In sec- tion II, we give a brief review of LDPC codes and the decod- ing algorithm. We introduce the cooperative system model in section III and propose the LDPC-DSTC systems in section IV. Simulation results are presented in section V. Section VI sum- marizes the results and concludes the paper. II. LOW-DENSITY PARITY-CHECK CODES