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arXiv · 1303.6167

Second-Order Rate Region of Constant-Composition Codes for the Multiple-Access Channel

Jonathan Scarlett·Alfonso Martinez·Albert Guillén i Fàbregas
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Abstract

This paper studies the second-order asymptotics of coding rates for the discrete memoryless multiple-access channel with a fixed target error probability. Using constant-composition random coding, coded time-sharing, and a variant of Hoeffding's combinatorial central limit theorem, an inner bound on the set of locally achievable second-order coding rates is given for each point on the boundary of the capacity region. It is shown that the inner bound for constant-composition random coding includes that recovered by i.i.d. random coding, and that the inclusion may be strict. The inner bound is extended to the Gaussian multiple-access channel via an increasingly fine quantization of the inputs.

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Jonathan Scarlett, Alfonso Martinez, Albert Guillén i Fàbregas. 2013-03-25. Second-Order Rate Region of Constant-Composition Codes for the Multiple-Access Channel. https://arxiv.org/abs/1303.6167

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