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arXiv · 1501.04394

Band Splitting Permutations for Spatially Coupled LDPC Codes Enhancing Burst Erasure Immunity

Hiroki Mori·Tadashi Wadayama
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Abstract

It is well known that spatially coupled (SC) codes with erasure-BP decoding have powerful error correcting capability over memoryless erasure channels. However, the decoding performance of SC-codes significantly degrades when they are used over burst erasure channels. In this paper, we propose band splitting permutations (BSP) suitable for $(l,r,L)$ SC-codes. The BSP splits a diagonal band in a base matrix into multiple bands in order to enhance the span of the stopping sets in the base matrix. As theoretical performance guarantees, lower and upper bounds on the maximal burst correctable length of the permuted $(l,r,L)$ SC-codes are presented. Those bounds indicate that the maximal correctable burst ratio of the permuted SC-codes converges to 1/k where k=r/l. This implies the asymptotic optimality of the permuted SC-codes in terms of burst erasure correction.

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Hiroki Mori, Tadashi Wadayama. 2015-01-19. Band Splitting Permutations for Spatially Coupled LDPC Codes Enhancing Burst Erasure Immunity. https://arxiv.org/abs/1501.04394

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