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International Symposium on Information Theory and its Applications

A new construction of irregular LDPC convolutional codes with cycle removal

Chi‐Jen Wu, Chung-Hsuan Wang, Chi-chao Chao

Published Oct 1, 2010• 0 citations
Publisher

Abstract

In this paper, a new construction of irregular low-density parity-check convolutional codes (LDPC-CCs) is presented. Both upper and lower bounds on the free distance are derived as well. Compared with previously constructed irregular LDPC-CCs, our design can not only avoid a girth less than 8 but also provide an enlarged free distance. Since some undesired cycles occur due to the binomial terms in the parity-check matrices of general LDPC-CCs, we provide a specific procedure to remove this kind of length-8 cycles. It can also be applied to our irregular construction. Simulation results show that the codes based on the new construction and the cycle-removal procedure can achieve better bit-error-rate performance and a lower error-floor.

DOI
10.1109/isita.2010.5650164

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