基于原模图的欧氏几何准循环LDPC码

Euclidean geometric quasi-cyclic LDPC code based on protograph

在保证欧氏几何准循环LDPC码围长不小于6的同时,为降低其译码门限,优化译码性能,引入原模图对欧氏几何准循环LDPC码构造方法加以改进。构造具有多边的原模图基矩阵,合并原欧氏几何码校验矩阵的部分循环子矩阵,以匹配原模图基矩阵。在加性高斯白噪声信道中进行迭代译码,采用改进方法所得准循环LDPC码在误比特率为10-5时,可获得0.1dB的编码增益。

In order to reduce the decoding threshold and optimize the decoding performance,the construction method of Euclidean geometric quasi-cyclic LDPC code with girth not less than 6 is improved by introducing the structure of protograph.The protograph base matrix with multiple edges is designed firstly,and then some circulant sub-matrices in the parity-check matrix of existing Euclidean geometric quasi-cyclic LDPC code are combined to match this protograph base matrix.When iterative decoding is used in additive white Gaussian noise channel,the quasi-cyclic LDPC code obtained by using the improved method can achieve a coding gain of 0.1 dB at the bit error rate of 10-5.