Polar Codes for Channels with Insertions, Deletions, and Substitutions

Henry D. Pfister; Ido Tal

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arXiv · 2102.02155

Polar Codes for Channels with Insertions, Deletions, and Substitutions

Henry D. Pfister·Ido Tal

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Abstract

This paper presents a coding scheme for an insertion deletion substitution channel. We extend a previous scheme for the deletion channel where polar codes are modified by adding "guard bands" between segments. In the new scheme, each guard band is comprised of a middle segment of '1' symbols, and left and right segments of '0' symbols. Our coding scheme allows for a regular hidden-Markov input distribution, and achieves the information rate between the input and corresponding output of such a distribution. Thus, we prove that our scheme can be used to efficiently achieve the capacity of the channel. The probability of error of our scheme decays exponentially in the cube-root of the block length.

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Henry D. Pfister, Ido Tal. 2021-02-03. Polar Codes for Channels with Insertions, Deletions, and Substitutions. https://arxiv.org/abs/2102.02155

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