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arXiv · 1206.3362

An Improved WBF Algorithm for Higher-Speed Decoding of LDPC Codes

Kexiang Ma·Yongzhao Li·Caizhi Zhu·Hailin Zhang·Feng Qi
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Abstract

Due to the speed limitation of the conventional bit-chosen strategy in the existing weighted bit flipping algorithms, a high-speed LDPC decoder cannot be realized. To solve this problem, we propose a fast weighted bit flipping (FWBF) algorithm. Specifically, based on the stochastic error bitmap of the received vector, a partially parallel bit-choose strategy is adopted to lower the delay of choosing the bit flipped. Because of its partially parallel structure, the novel strategy can be well incorporated into the LDPC decoder [1]. The analysis of the decoding delay demonstrates that, the decoding speed can be greatly improved by adopting the proposed FWBF algorithm. Further, simulation results verify the validity of the proposed algorithm.

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Kexiang Ma, Yongzhao Li, Caizhi Zhu, Hailin Zhang, Feng Qi. 2012-06-15. An Improved WBF Algorithm for Higher-Speed Decoding of LDPC Codes. https://arxiv.org/abs/1206.3362

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