International Conference on Wireless Communications and Signal Processing (WCSP)

Constructions of Girth-Eight QC-LDPC Codes with Dual-Diagonal Structure Based on GCD Framework

Guohua Zhang, Haiyang Liu, Mengjuan Lou, Yi Fang

Published Nov 2, 2023• 5 citations

Abstract

A novel class of quasi-cyclic (QC) low-density parity-check (LDPC) codes is explicitly proposed without 4-cycles and 6-cycles via the greatest-common-divisor (GCD) framework. From the new codes, a novel type of girth-eight QC-LDPC codes with a dual-diagonal (DD) structure is presented, in which the single undetermined entry in the associated exponent matrix can be determined by simple formulae. The proposed DD codes have similar or better performance compared with DD codes obtained from computer search. Moreover, a lower bound on circulant sizes which guarantees the existence of qualified undetermined entries is also provided.

DOI: 10.1109/wcsp58612.2023.10405132

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