高斯白噪声信道下SC-LDPC码的结构设计

Structure Design of SC-LDPC Code over Additive White Gaussian Noise Channel

为了优化空间耦合低密度奇偶校验(SC-LDPC)码在加性高斯白噪声信道下的性能,改变了其边缘扩展规则,将规则SC-LDPC码原模图上变量节点的边连接到与其相对应的前一个位置的校验节点上,提出了一种新型的空间耦合结构.对其基矩阵、码率、度分布及译码复杂度进行分析,结果表明,与传统的SC-LDPC码相比,链长相同时,新结构的码率有所提高,校验节点的度分布变大.最后通过BP译码验证了提出的空间耦合新结构译码性能的优越性.

In order to optimize the performance of spatially coupled low density parity check(SC-LDPC)codes over the additive white gaussian noise channel,a novel spatial coupling structure was proposed by changing the edge spreading rules,the edges of the variable nodes were connected to the check nodes of the previous position.Basis matrix,rate,degree distribution and computational complexity were analyzed and the results show that the rate of the novel structure is promoted with the degree distribution of check nodes become larger.Finally,the performance of the proposed novel structure is verified by BP decoding.