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arXiv · 1411.7282

Successive Cancellation List Polar Decoder using Log-likelihood Ratios

Bo Yuan·Keshab K. Parhi
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Abstract

Successive cancellation list (SCL) decoding algorithm is a powerful method that can help polar codes achieve excellent error-correcting performance. However, the current SCL algorithm and decoders are based on likelihood or log-likelihood forms, which render high hardware complexity. In this paper, we propose a log-likelihood-ratio (LLR)-based SCL (LLR-SCL) decoding algorithm, which only needs half the computation and storage complexity than the conventional one. Then, based on the proposed algorithm, we develop low-complexity VLSI architectures for LLR-SCL decoders. Analysis results show that the proposed LLR-SCL decoder achieves 50% reduction in hardware and 98% improvement in hardware efficiency.

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Bo Yuan, Keshab K. Parhi. 2014-11-26. Successive Cancellation List Polar Decoder using Log-likelihood Ratios. https://arxiv.org/abs/1411.7282

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