Rate-Adaptive Spatially Coupled MacKay-Neal Codes with Thresholds Close to Capacity

Ayman Zahr; Gianluigi Liva

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arXiv · 2510.14843

Rate-Adaptive Spatially Coupled MacKay-Neal Codes with Thresholds Close to Capacity

Ayman Zahr·Gianluigi Liva

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Abstract

We analyze by density evolution the asymptotic performance of rate-adaptive MacKay-Neal (MN) code ensembles, where the inner code is a protograph spatially coupled (SC) low-density parity-check code. By resorting to a suitably-defined parallel channel model, we compute belief propagation decoding thresholds, showing that SC MN code ensembles can perform within 0.15 dB from the binary-input additive white Gaussian noise capacity over the full [0,1] rate range.

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Ayman Zahr, Gianluigi Liva. 2025-10-16. Rate-Adaptive Spatially Coupled MacKay-Neal Codes with Thresholds Close to Capacity. https://arxiv.org/abs/2510.14843

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