仿射置换矩阵结构下的高性能SC-LDPC码  

High Performance SC-LDPC Code Based on Affine Permutation Matrices

作　　者：朱坤 杨鸿文[1] ZHU Kun;YANG Hongwen(School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China)

机构地区：[1]北京邮电大学信息与通信工程学院,北京100876

出　　处：《北京邮电大学学报》2022年第2期131-136,共6页Journal of Beijing University of Posts and Telecommunications

摘　　要：空间耦合(SC)低密度奇偶校验(LDPC)码的卷积结构在带来卷积增益的同时也引入了记忆结构。对于采用滑动窗译码的SC-LDPC码,前面的译码错误信息会影响后面的译码,尤其是对耦合长度较长的SC-LDPC码,容易引起误码扩散。因此,SC-LDPC码比传统的LDPC块码对结构设计的要求更高。为了提高设计空间和性能,提出用仿射置换矩阵(APM)替代传统的循环位移矩阵构造SC-LDPC码。通过实验发现并证明了APM-LDPC码结构具有全环和非全环现象,且非全环现象仅出现在APM-LDPC码中。应用非全环现象构造的APM-SC-LDPC码能显著降低短环数量和误码平层,在瀑布区有明显优势。Spatially-coupled(SC) low density parity check(LDPC) code is a kind of LDPC code with convolution structure. This structure not only brings convolution gain but also introduces memory structure. For codes using sliding window decoding, the previous error message will affect the subsequent decoding, especially for SC-LDPC codes with long coupling length, which is easy to cause error propagation. Therefore, SC-LDPC codes have stricter requirements for structural design than traditional LDPC block codes. To improve the design space and performance of SC-LDPC codes, an affine permutation matrix(APM) is proposed to replace the traditional cyclic permutation matrix for code construction. The full cycles and non-full cycles phenomena in APM-LDPC code’s structures are discovered and demonstrated, and the non-full cycles phenomenon only occurs in APM-LDPC code is proved. The APM-SC-LDPC code with non-full cycles phenomenon can significantly reduce the number of short cycles, the error-floor and significantly improve in waterfall region.

关 键 词：仿射置换矩阵 空间耦合LDPC码 环分布 瀑布区 错误平层 

分 类 号：TN911.22[电子电信—通信与信息系统]