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arXiv · 1402.0898

Interference Channels with Half-Duplex Source Cooperation

Rui Wu·Vinod Prabhakaran·Pramod Viswanath·Yi Wang
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Abstract

The performance gain by allowing half-duplex source cooperation is studied for Gaussian interference channels. The source cooperation is {\em in-band}, meaning that each source can listen to the other source's transmission, but there is no independent (or orthogonal) channel between the sources. The half-duplex constraint supposes that at each time instant the sources can either transmit or listen, but not do both. Our main result is a characterization of the sum capacity when the cooperation is bidirectional and the channel gains are symmetric. With unidirectional cooperation, we essentially have a cognitive radio channel. By requiring the primary to achieve a rate close to its link capacity, the best possible rate for the secondary is characterized within a constant. Novel inner and outer bounds are derived as part of these characterizations.

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Rui Wu, Vinod Prabhakaran, Pramod Viswanath, Yi Wang. 2014-02-04. Interference Channels with Half-Duplex Source Cooperation. https://arxiv.org/abs/1402.0898

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