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Polar Codes for Channels with Insertions, Deletions, and Substitutions

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 نشر من قبل Ido Tal
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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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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