Quasi Cyclic Low Density Parity Check Code for High SNR Data Transfer

Abstract

An improved Quasi Cyclic Low Density Parity Check code (QC-LDPC) is proposed to reduce the complexity of the Low Density Parity Check code (LDPC) while obtaining the similar performance. The proposed QC-LDPC presents an improved construction at high SNR with circulant sub-matrices. The proposed construction yields a performance gain of about 1 dB at a 0.0003 bit error rate (BER) and it is tested on 4 different decoding algorithms. Proposed QC-LDPC is compared with the existing QC-LDPC and the simulation results show that the proposed approach outperforms the existing one at high SNR. Simulations are also performed varying the number of horizontal sub matrices and the results show that the parity check matrix with smaller horizontal concatenation shows better performance.