Research on Construction Algorithm of Large Circulant LDPC Codes

One approach to improve the performance of Low-Density Parity-Check (LDPC) code was to address the presence of short cycles. In this paper, a variable-degree scoring algorithm was presented, designed for both general LDPC codes and Quasi-Cyclic (QC) LDPC codes, with the goal of eliminating short cycles and evaluating the impact on decoding performance. Scores were assigned to the non-zero elements in the LDPC codes based on their involvement in short cycles by the algorithm, and the elements with the highest scores were subsequently modified. Our algorithm effectively eliminated short cycles and improved decoding performance.