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arXiv · 2001.11283

SCAN List Decoding of Polar Codes

Charles Pillet·Carlo Condo·Valerio Bioglio
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Abstract

In this paper we propose an enhanced soft cancellation (SCAN) decoder for polar codes based on decoding stages permutation. The proposed soft cancellation list (SCANL) decoder runs $L$ independent SCAN decoders, each one relying on a different permuted factor graph. The estimated bits are selected among the $L$ candidates through a dedicated metric provided by the decoders. Furthermore, we introduce an early-termination scheme reducing decoding latency without affecting error correction performance. We investigate the error-correction performance of the proposed scheme under various combinations of number of iterations used, permutation set and early-termination condition. Simulation results show that the proposed SCANL provides similar results when compared with belief propagation list, while having a smaller complexity. Moreover, for large list sizes, SCANL outperforms non-CRC aided successive cancellation list decoding.

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Charles Pillet, Carlo Condo, Valerio Bioglio. 2020-01-30. SCAN List Decoding of Polar Codes. https://arxiv.org/abs/2001.11283

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