A new LDPC decoding scheme for PDM-8QAM BICM coherent optical communication system  

作　　者：刘怡 张文博 席丽霞 唐先锋 张晓光 

机构地区：[1]State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications [2]School of Science, Beijing University of Posts and Telecommunications

出　　处：《Optoelectronics Letters》2015年第6期449-452,共4页光电子快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.61205065);the Fund of State Key Laboratory of Information Photonics and Optical Communications;the Fundamental Research Funds for the Central Universities in China(No.2014RC1201)

摘　　要：A new log-likelihood ratio(LLR) message estimation method is proposed for polarization-division multiplexing eight quadrature amplitude modulation(PDM-8QAM) bit-interleaved coded modulation(BICM) optical communication system.The formulation of the posterior probability is theoretically analyzed,and the way to reduce the pre-decoding bit error rate(BER) of the low density parity check(LDPC) decoder for PDM-8QAM constellations is presented.Simulation results show that it outperforms the traditional scheme,i.e.,the new post-decoding BER is decreased down to 50%of that of the traditional post-decoding algorithm.

关 键 词：相干光通信系统 LDPC码 译码 比特交织编码调制 低密度奇偶校验 合作 正交幅度调制 解码方法 

分 类 号：TN929.1[电子电信—通信与信息系统] TN911.22[电子电信—信息与通信工程]