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arXiv · 1207.6540

Achieving Net Feedback Gain in the Butterfly Network with a Full-Duplex Bidirectional Relay

Anas Chaaban·Aydin Sezgin·Daniela Tuninetti
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Abstract

A symmetric butterfly network (BFN) with a full-duplex relay operating in a bi-directional fashion for feedback is considered. This network is relevant for a variety of wireless networks, including cellular systems dealing with cell-edge users. Upper bounds on the capacity region of the general memoryless BFN with feedback are derived based on cut-set and cooperation arguments and then specialized to the linear deterministic BFN with really-source feedback. It is shown that the upper bounds are achievable using combinations of the compute-forward strategy and the classical decode-and-forward strategy, thus fully characterizing the capacity region. It is shown that net rate gains are possible in certain parameter regimes.

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Anas Chaaban, Aydin Sezgin, Daniela Tuninetti. 2012-07-27. Achieving Net Feedback Gain in the Butterfly Network with a Full-Duplex Bidirectional Relay. https://arxiv.org/abs/1207.6540

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