IEEE Communications Letters

Recursive Design of High Girth (2,k) LDPC Codes from (k,k) LDPC Codes

Xiongfei Tao, Lixin Zheng, Weizhong Liu, Dongsheng Liu

Published Dec 10, 2010• 12 citations

Abstract

An approach to construct column-weight-2 LDPC codes with high girth is presented. The approach derives a column-weight-2 LDPC code from the Tanner graph of a (k,k) QC-LDPC code. By the construction, the new LDPC codes double in girth. To construct the (k,k) QC-LDPC codes with desired girth, a search algorithm is proposed in this paper. The approach generates an example of a (2,3) LDPC code with a girth of 36, which is larger than the column-weight-2 LDPC codes constructed by the previously methods.

DOI: 10.1109/lcomm.2010.112310.101867

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