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arXiv · 1202.1060

A Non-Disjoint Group Shuffled Decoding for LDPC Codes

Yen-Cheng Hsu·Tofar C. -Y. Chang·Yu T. Su·Jian-Jia Weng
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Abstract

To reduce the implementation complexity of a belief propagation (BP) based low-density parity-check (LDPC) decoder, shuffled BP decoding schedules, which serialize the decoding process by dividing a complete parallel message-passing iteration into a sequence of sub-iterations, have been proposed. The so-called group horizontal shuffled BP algorithm partitions the check nodes of the code graph into groups to perform group-by-group message-passing decoding. This paper proposes a new grouping technique to accelerate the message-passing rate. Performance of the proposed algorithm is analyzed by a Gaussian approximation approach. Both analysis and numerical experiments verify that the new algorithm does yield a convergence rate faster than that of existing conventional or group shuffled BP decoder with the same computing complexity constraint.

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Yen-Cheng Hsu, Tofar C. -Y. Chang, Yu T. Su, Jian-Jia Weng. 2012-02-06. A Non-Disjoint Group Shuffled Decoding for LDPC Codes. https://arxiv.org/abs/1202.1060

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