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arXiv · 1102.3235

K-user Interference Channels: General Outer Bound and Sum-capacity for Certain Gaussian Channels

Daniela Tuninetti
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Abstract

This paper derives an outer bound on the capacity region of a general memoryless interference channel with an arbitrary number of users. The derivation follows from a generalization of the techniques developed by Kramer and by Etkin et al for the Gaussian two-user channel. The derived bound is the first known outer bound valid for any memoryless channel. In Gaussian noise, classes of channels for which the proposed bound gives the sum-rate capacity are identified, including degraded channels and a class of Z-channels.

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Daniela Tuninetti. 2011-02-16. K-user Interference Channels: General Outer Bound and Sum-capacity for Certain Gaussian Channels. https://doi.org/10.1109/isit.2011.6033716

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