Pseudocodeword-Free Criterion for Codes with Cycle-Free Tanner Graph

Wittawat Kositwattanarerk

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arXiv · 1706.06648

Pseudocodeword-Free Criterion for Codes with Cycle-Free Tanner Graph

Wittawat Kositwattanarerk

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Abstract

Iterative decoding and linear programming decoding are guaranteed to converge to the maximum-likelihood codeword when the underlying Tanner graph is cycle-free. Therefore, cycles are usually seen as the culprit of low-density parity-check (LDPC) codes. In this paper, we argue in the context of graph cover pseudocodeword that, for a code that permits a cycle-free Tanner graph, cycles have no effect on error performance as long as they are a part of redundant rows. Specifically, we characterize all parity-check matrices that are pseudocodeword-free for such class of codes.

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Wittawat Kositwattanarerk. 2017-06-20. Pseudocodeword-Free Criterion for Codes with Cycle-Free Tanner Graph. https://arxiv.org/abs/1706.06648

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