Journal of Chinese Computer Systems

Designing Linear Encoder for Structured LDPC Codes with Large Girth

Qiongxia Shen

Published Jan 1, 2010• 0 citations

Abstract

A parity-check matrix H with large girth has important significance to improve the performance of LDPC codes.And the key to the encoder implementation is the algebraic code structure.In this paper,a novel method based on Column-Difference Search Algorithm and Progressive Edge Growth Algorithm is proposed to design Quasi-Cyclic LDPC codes with arbitrary girth and code rate.Due to its almost lower triangular form,CP-LDPC code has linear encoding complexity.The experimental results show that CP-LDPC codes perform better than Tanner codes and Array codes,which are another two classical QC-LDPC codes,and random codes.The code in this paper outperforms random code,Tanner code and Array code by 1.35dB-3.95dB.

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