Journal of Communications

Explicit construction of girth-eight QC-LDPC codes and its application in CRT method

Xinmei Wang

Published Jan 1, 2012• 8 citations

Abstract

For arbitrary code lengths of the form PL(P≥3L2/4+L?1),a new family of(4,L)-regular quasi-cyclic(QC) low-density parity-check(LDPC) codes was proposed explicitly with girth eight.Employing the new code as a compo-nent code in the construction method of Chinese remainder theorem(CRT),a novel class of compound QC-LDPC codes was presented with both girth at least eight and very flexible code lengths.Simulation results show that the new compound codes with rate 1/2 and moderate code lengths perform very well over the additive white Gaussian noise(AWGN) channel.

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