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arXiv · 1310.1732

The Approximate Capacity Region of the Gaussian Y-Channel

Anas Chaaban·Aydin Sezgin
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Abstract

A full-duplex wireless network with three users that want to establish full message-exchange via a relay is considered. Thus, the network known as the Y-channel has a total of 6 messages, 2 outgoing and 2 incoming at each user. The users are not physically connected, and thus the relay is essential for their communication. The linear-shift deterministic Y-channel is considered first, its capacity region is characterized and shown not to be given by the cut-set bounds. The capacity achieving scheme has three different components (strategies): a bi-directional, a cyclic, and a uni-directional strategy. Network coding is used to realize the bi-directional and the cyclic strategies, and thus to prove the achievability of the capacity region. The result is then extended to the Gaussian Y-channel where the capacity region is characterized within a constant gap independent of the channel parameters.

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Anas Chaaban, Aydin Sezgin. 2013-10-07. The Approximate Capacity Region of the Gaussian Y-Channel. https://arxiv.org/abs/1310.1732

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