一种高码率低复杂度准循环LDPC码设计研究  

A Class of High-Rate Low-Complexity QC-LDPC Codes

作　　者：敬龙江[1] 林竞力[1] 朱维乐[1] 

机构地区：[1]电子科技大学电子工程学院,成都610054

出　　处：《电子与信息学报》2008年第6期1385-1389,共5页Journal of Electronics & Information Technology

基　　金：韩国三星公司项目基金(HO4010201WO20340)资助课题

摘　　要：该文设计了一种特殊的高码率准循环低密度校验(QC-LDPC)码,其校验矩阵以单位矩阵的循环移位阵为基本单元,与随机构造的LDPC码相比可节省大量存储单元。利用该码校验矩阵的近似下三角特性,一种高效的递推编码方法被提出,它使得该码编码复杂度与码长成线性关系。另外,该文提出一种分析QC-LDPC码二分图中短长度环分布情况的方法,并且给出了相应的不含长为4环QC-LDPC码的构造方法。计算机仿真结果表明,新码不但编码简单,而且具有高纠错能力、低误码平层。This paper proposes a class of Quasi-Cyclic Low-Density Parity-Check （QC-LDPC） codes with high code rates, which is an efficient encoding algorithm due to the almost lower triangular form and simple structure of their parity-check matrices. Since the parity-check matrix of the QC-LDPC code is composed of blocks of circulant matrices, the required memory for storing it can be significantly reduced, compared with randomly constructed LDPC codes. Based on the quasi-cyclic structure of the parity-check matrix, a new approach is proposed to analyze the distribution of the short length cycles of their bipartite graph, and a corresponding construction method of QC-LDPC codes without cycles of length 4 is presented. Simulation results show that the proposed codes not only have low encoding complexity and low error floor but also perform well with iterative decoding.

关 键 词：QC-LDPC码 BP迭代译码 高效编码 二分图 

分 类 号：TN911.22[电子电信—通信与信息系统]