多进制高斯信道下四进制LDPC码的实现

Implementation of 4-ary LDPC Codes under Non-binary AWGN Channel

四进制低密度校验码(Low-Density Parity-Check Code,LDPC)具有较好的抗突发差错性能。为了进一步改善系统的性能并适当降低其复杂度,在二进制LDPC码的基础上,主要研究短码长四进制LDPC码,并在原有串行译码算法的基础上对其改进,提出一种基于校验点准确度的串行译码算法。仿真结果表明,在多进制高斯信道条件下,对于短码而言,改进的串行译码算法性能要优于串行译码算法,在误码率为10-2时,能获得0.25 d B的编码增益。

4-ary LDPC （ Low-Density Parity-Check） Code has better performance of resistance to burst errors. To improve performance and reduce the complexity of algorithm,this paper mainly about the research of 4-ary LDPC codes with a short code length based on binary LDPC codes.Based on the layer belief propagation,this paper proposes serial decoding algorithm based on the accuracy of check node. Under non-binary AWGN channel, in terms of a short code length, simulation results show that the performance of improved serial decoding algorithm is better than layer belief propagation,it can achieve 0.25dB performance gain at the symbol error rate of 10^-2 .