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arXiv · 1107.4965

Polar codes for q-ary channels, q=2^r

Woomyoung Park·Alexander Barg
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Abstract

We study polarization for nonbinary channels with input alphabet of size q=2^r,r=2,3,... Using Arikan's polarizing kernel H_2, we prove that the virtual channels that arise in the process of polarization converge to q-ary channels with capacity 1,2,...,r bits, and that the total transmission rate approaches the symmetric capacity of the channel. This leads to an explicit transmission scheme for q-ary channels. The error probability of decoding using successive cancellation behaves as exp(-N^α), where N is the code length and α is any constant less than 0.5.

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Woomyoung Park, Alexander Barg. 2012-01-24. Polar codes for q-ary channels, q=2^r. https://arxiv.org/abs/1107.4965

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