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arXiv · 1407.0124

Single-Letter Characterization of Epsilon-Capacity for Mixed Memoryless Channels

Hideki Yagi·Ryo Nomura
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Abstract

For the class of mixed channels decomposed into stationary memoryless channels, single-letter characterizations of the $\varepsilon$-capacity have not been known except for restricted classes of channels such as the regular decomposable channel introduced by Winkelbauer. This paper gives single-letter characterizations of $\varepsilon$-capacity for mixed channels decomposed into at most countably many memoryless channels with a finite input alphabet and a general output alphabet with/without cost constraints. It is shown that a given characterization reduces to the one for the channel capacity given by Ahlswede when $\varepsilon$ is zero. In the proof of the coding theorem, the meta converse bound, originally given by Polyanskiy, Poor and Verdú, is particularized for the mixed channel decomposed into general component channels.

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Hideki Yagi, Ryo Nomura. 2014-07-01. Single-Letter Characterization of Epsilon-Capacity for Mixed Memoryless Channels. https://arxiv.org/abs/1407.0124

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