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arXiv · 2410.15071

Soft-Output Fast Successive-Cancellation List Decoder for Polar Codes

Li Shen·Yongpeng Wu·Yin Xu·Xiaohu You·Xiqi Gao·Wenjun Zhang
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Abstract

The soft-output successive cancellation list (SOSCL) decoder provides a methodology for estimating the a-posteriori probability log-likelihood ratios by only leveraging the conventional SCL decoder for polar codes. However, the sequential nature of SCL decoding leads to a high decoding latency for the SO-SCL decoder. In this paper, we propose a soft-output fast SCL (SO-FSCL) decoder by incorporating node-based fast decoding into the SO-SCL framework. Simulation results demonstrate that the proposed SO-FSCL decoder significantly reduces the decoding latency without loss of performance compared with the SO-SCL decoder.

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Li Shen, Yongpeng Wu, Yin Xu, Xiaohu You, Xiqi Gao, Wenjun Zhang. 2024-10-19. Soft-Output Fast Successive-Cancellation List Decoder for Polar Codes. https://arxiv.org/abs/2410.15071

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