Channel Upgradation for Non-Binary Input Alphabets and MACs

Uzi Pereg; Ido Tal

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arXiv · 1308.5793

Channel Upgradation for Non-Binary Input Alphabets and MACs

Uzi Pereg·Ido Tal

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Abstract

Consider a single-user or multiple-access channel with a large output alphabet. A method to approximate the channel by an upgraded version having a smaller output alphabet is presented and analyzed. The original channel is not necessarily symmetric and does not necessarily have a binary input alphabet. Also, the input distribution is not necessarily uniform. The approximation method is instrumental when constructing capacity achieving polar codes for an asymmetric channel with a non-binary input alphabet. Other settings in which the method is instrumental are the wiretap setting as well as the lossy source coding setting.

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Uzi Pereg, Ido Tal. 2013-08-27. Channel Upgradation for Non-Binary Input Alphabets and MACs. https://arxiv.org/abs/1308.5793

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