Girth-12 Quasi-Cyclic LDPC Codes with Consecutive Lengths

Guohua Zhang; Xinmei Wang

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arXiv · 1001.3916

Girth-12 Quasi-Cyclic LDPC Codes with Consecutive Lengths

Guohua Zhang·Xinmei Wang

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Abstract

A method to construct girth-12 (3,L) quasi-cyclic low-density parity-check (QC-LDPC) codes with all lengths larger than a certain given number is proposed, via a given girth-12 code subjected to some constraints. The lengths of these codes can be arbitrary integers of the form LP, provided that P is larger than a tight lower bound determined by the maximal element within the exponent matrix of the given girth-12 code. By applying the method to the case of row-weight six, we obtained a family of girth-12 (3,6) QC-LDPC codes for arbitrary lengths above 2688, which includes 30 member codes with shorter code lengths compared with the shortest girth-12 (3,6) QC-LDPC codes reported by O'Sullivan.

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Guohua Zhang, Xinmei Wang. 2010-01-22. Girth-12 Quasi-Cyclic LDPC Codes with Consecutive Lengths. https://arxiv.org/abs/1001.3916

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