具有低误码平层的准3-对角线结构QC-LDPC码的高效编码方法  

Efficient Encoding Method for QC-LDPC Codes with Quasi Tri-Diagonal Structure and Low Error Floors

作　　者：赵明 刘志鹏[1] ZHAO Ming;LIU Zhi-peng(China Academy of Electronics and Information Technology,Beijing 100041,China)

机构地区：[1]中国电子科学研究院,北京100041

出　　处：《中国电子科学研究院学报》2020年第2期159-165,共7页Journal of China Academy of Electronics and Information Technology

基　　金：中国国家自然科学基金项目(61771047).

摘　　要：具有特殊结构的准循环低密度奇偶校验(Quasi-Cyclic Low Density Parity-Check,QC-LDPC)码可实现快速编码,而校验矩阵列重至少为3的QC-LDPC码可降低误码平层,因此本文提出具有准3-对角线结构的QC-LDPC码及其编码方法。所提出的QC-LDPC码可通过存储提取矩阵的逆矩阵和校验矩阵迭代的方法实现高效编码,于是可降低编码复杂度。并且其校验矩阵列重至少为3,可在低误码率范围内获得较好的译码性能,降低误码平层。同时本文还针对具有准3-对角线结构的QC-LDPC码提出基于增强的近似环外信息度(Approximate Cycle Extrinsic message degree,ACE)优化构造方法。不同结构的LDPC码用于和所提出的QC-LDPC码进行测试和比较。实验结果表明,所提出的码在较高信噪比条件下可获得较好的译码性能,降低误码平层,同时降低编码复杂度。Quasi-Cyclic Low Density Parity-Check(QC-LDPC)codes with special structures can be fast encoded,and QC-LDPC codes,whose column weights of parity-check matrices are at least 3,can lower the error floors.Thus the QC-LDPC codes with quasi tri-diagonal structure and the corresponding encoding method are proposed.The proposed codes fulfill the efficient encoding by the inverse matrices of extracted matrices and iterative calculation with parity-check matrices,thus lowering the encoding complexity.The column weights of proposed parity-check matrices are at least 3,thus the proposed codes can obtain good decoding performance at low Bit Error Ratio(BER)regions,lowering the error floors.The enhanced Approximate Cycle Extrinsic message degree(ACE)optimization is also presented for proposed QC-LDPC codes with quasi tri-diagonal structure.Different QC-LDPC codes with different structures are used to compare with the new designed codes.Experimental results show that the proposed QC-LDPC codes obtain good decoding performance at high Signal to Noise Ratios(SNRs)and lower the error floors,while with low encoding complexity.

关 键 词：QC-LDPC码 高效编码 误码平层 准3-对角线结构 增强的ACE优化方法 度分布 

分 类 号：TN911.22[电子电信—通信与信息系统]