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IFIP International Conference on Wireless and Optical Communications Networks (WOCN)

Analysis of balanced cycles of QC-LDPC codes

Xiao Rong Gao, Nan Zhang

Published May 1, 2011• 2 citations
Publisher

Abstract

In this paper, we analyze balanced cycles of quasi-cyclic low-density parity-check (QC-LDPC) codes. We show the structure of balanced cycles and their necessary and sufficient existence conditions. Furthermore, we determine the minimal matrices of balanced cycle. Meanwhile we propose the property of B-girth in its mother matrix. Finally, we give the proof in theory.

DOI
10.1109/wocn.2011.5872931

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In this paper, we analyze balanced cycles of quasi-cyclic low-density parity-check (QC-LDPC) codes. We show the structure of balanced cycles and their necessary and sufficient existence conditions. Furthermore, we determine the minimal matrices of balanced cycle. Meanwhile we propose the property of B-girth in its mother matrix. Finally, we give the proof in theory.
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In this paper we investigate the cycle properties of regular quasi-cyclic low-density parity-check (QC-LDPC) codes. Using the sequence representation, we analyze the conditions for short cycles to exist in regular QC-LDPC codes and then give necessary conditions for avoiding short cycles in terms of their parameters. Numerical results show that our bounds on the number of rows in the parity-check matrices for regular QC-LDPC codes without cycles of length 4 or 6 are tighter than any other known bounds.