Journal of Optoelectronics·laser

A novel construction method of QC-LDPC codes based on Galois field multiplicative group

Yong Wang

Published Jan 1, 2012• 0 citations

Abstract

A novel construction method with the advantages of simple construction and easy implementation encoding for quasi-cyclic low-density parity-check(QC-LDPC) codes based on Galois field(GF(q)) multiplicative group is proposed.This algorithm can flexibly adjust code length and code rate Furthermore,the complexity of the encoding and decoding is low.An irregular QC-LDPC(3843,3603) code suitable for optical communication systems is constructed by applying the proposed construction method.The simulation results show that the error-correction performance of the QC-LDPC(3843,3603) code is better than that of the classic RS(255,239) code,the LDPC code constructed by the SCG construction method,and the regular QC-LDPC(4221,3956) code.So the QC-LDPC(3843,3603) code is suitable for the high-speed long-haul optical communication systems.

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