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arXiv · 2306.17451

Self-Connected Spatially Coupled LDPC Codes with Improved Termination

Yihuan Liao·Min Qiu·Jinhong Yuan
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Abstract

This paper investigates the design of self-connected spatially coupled low-density parity-check (SC-LDPC) codes. First, a termination method is proposed to reduce rate loss. Particularly, a single-side open SC-LDPC ensemble is introduced, which halves the rate loss of a conventional terminated SC-LDPC by reducing the number of check nodes. We further propose a self-connection method that allows reliable information to propagate from several directions to improve the decoding threshold. We demonstrate that the proposed ensembles not only achieve a better trade-off between rate loss and gap to capacity than several existing protograph SC-LDPC codes with short chain lengths but also exhibit threshold saturation behavior. Finite blocklength error performance is provided to exemplify the superiority of the proposed codes over conventional protograph SC-LDPC codes.

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Yihuan Liao, Min Qiu, Jinhong Yuan. 2023-06-30. Self-Connected Spatially Coupled LDPC Codes with Improved Termination. https://arxiv.org/abs/2306.17451

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