Bandaoti guangdian

A Construction Method of QC-LDPC Codes Based on Finite Field Cyclic Subgroup for Optical Communications

Yuan Jiangu

Published Jan 1, 2013• 0 citations

Abstract

A construction method of Quasi-Cyclic Low-Density Parity-Check(QC-LDPC) codes based on cyclic subgroups of finite field is proposed.The method owns the advantages such as easier construction,more flexible adjustment on code-length and code-rate and lower encoding/ decoding complexity.Moreover,a regular QC-LDPC(5334,4955)code suitable for optical communication systems is constructed by this construction method.The simulation results show that the code can gain good performance under the condition of additive white Gaussian noise(AWGN)channel with iterative decoding sum-product algorithm(SPA).The error-correction performance of the QC-LDPC(5334,4955)code is better than that of the classic RS(255,239) code which is widely used in optical communication system.Therefore,the constructed QC-LDPC(5334,4955)code can be better suitable for the long-haul and high-speed optical communication systems.

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