A General Coding Scheme for Two-User Fading Interference Channels

Lalitha Sankar; Elza Erkip; H. Vincent Poor

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arXiv · 1001.2786

A General Coding Scheme for Two-User Fading Interference Channels

Lalitha Sankar·Elza Erkip·H. Vincent Poor

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Abstract

A Han-Kobayashi based achievable scheme is presented for ergodic fading two-user Gaussian interference channels (IFCs) with perfect channel state information at all nodes and Gaussian codebooks with no time-sharing. Using max-min optimization techniques, it is shown that jointly coding across all states performs at least as well as separable coding for the sub-classes of uniformly weak (every sub-channel is weak) and hybrid (mix of strong and weak sub-channels that do not achieve the interference-free sum-capacity) IFCs. For the uniformly weak IFCs, sufficient conditions are obtained for which the sum-rate is maximized when interference is ignored at both receivers.

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Lalitha Sankar, Elza Erkip, H. Vincent Poor. 2010-01-15. A General Coding Scheme for Two-User Fading Interference Channels. https://arxiv.org/abs/1001.2786

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