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arXiv · 1209.5762

Nonbinary Spatially-Coupled LDPC Codes on the Binary Erasure Channel

Amina Piemontese·Alexandre Graell i Amat·Giulio Colavolpe
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Abstract

We analyze the asymptotic performance of nonbinary spatially-coupled low-density parity-check (SC-LDPC) codes built on the general linear group, when the transmission takes place over the binary erasure channel. We propose an efficient method to derive an upper bound to the maximum a posteriori probability (MAP) threshold for nonbinary LDPC codes, and observe that the MAP performance of regular LDPC codes improves with the alphabet size. We then consider nonbinary SC-LDPC codes. We show that the same threshold saturation effect experienced by binary SC-LDPC codes occurs for the nonbinary codes, hence we conjecture that the BP threshold for large termination length approaches the MAP threshold of the underlying regular ensemble.

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Amina Piemontese, Alexandre Graell i Amat, Giulio Colavolpe. 2012-09-25. Nonbinary Spatially-Coupled LDPC Codes on the Binary Erasure Channel. https://doi.org/10.1109/icc.2013.6655049

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