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arXiv · 2301.02294

Polar Codes with Local-Global Decoding

Ziyuan Zhu·Wei Wu·Paul H. Siegel
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Abstract

In this paper, we investigate a coupled polar code architecture that supports both local and global decoding. This local-global construction is motivated by practical applications in data storage and transmission where reduced-latency recovery of sub-blocks of the coded information is required. Local decoding allows random access to sub-blocks of the full code block. When local decoding performance is insufficient, global decoding provides improved data reliability. The coupling scheme incorporates a systematic outer polar code and a partitioned mapping of the outer codeword to semipolarized bit-channels of the inner polar codes. Error rate simulation results are presented for 2 and 4 sub-blocks. Design issues affecting the trade-off between local and global decoding performance are also discussed.

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Ziyuan Zhu, Wei Wu, Paul H. Siegel. 2023-01-05. Polar Codes with Local-Global Decoding. https://arxiv.org/abs/2301.02294

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