LDPC-Coded Cooperative System Based on Joint Iterative Decoding
Shunwai Zhang, Fengfan Yang, Peng Zong · Journal of Southwest Jiaotong University · 2011
In order to improve the performances of a communication system,new coded cooperative communication schemes employing regular LDPC(low-density parity-check code) and irregular systematic LDPC codes respectively were proposed,and the methods of constructing the double LDPC codes used by source and relay nodes were given.The overall parity-check matrix corresponding to the double LDPC codes was deduced,then the bilayer Tanner graph of the deduced parity-check matrix was given.A new joint iterative decoding algorithm based on the bilayer Tanner graph was used for decoding of the destination node.Theoretical analysis and simulation results show that the proposed ideal LDPC-coded cooperative schemes offer a significant performance gain over the coded non-cooperative scheme under the same conditions.Under the conditions of a BER(bit error rate) of 10-5 and 10 decoding iterations,the ideal regular LDPC and irregular systematic LDPC-coded cooperative schemes achieve respectively 1.0 and 0.6 dB gains over the coded non-cooperative scheme.