Construction Based on Conditional-Filling with Cyclic Shift Identity Matrices for LDPC Codes
基于循环转置单位矩阵条件填充的LDPC码构造方法

By analysis and the sufficient utilization of characteristics of the cyclic shift identity matrices in a cycle, the construction based on conditional-filling with shift matrices for LDPC codes is presented, the upper and lower bounds of girth of the check matrix which had been constructed by this scheme is also proposed, and a concrete conditional-filling construction is thus proposed, the simulations prove that the construction can reduce the amount of least cycle of the check matrix remarkably and improve the performance to a larger extent.