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arXiv · 1302.0749

Multi-Way Information Exchange Over Completely-Connected Interference Networks with a Multi-Antenna Relay

Namyoon Lee·Robert W. Heath Jr
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Abstract

This paper considers a fully-connected interference network with a relay in which multiple users equipped with a single antenna want to exchange multiple unicast messages with other users in the network by sharing the relay equipped with multiple antennas. For such a network, the degrees of freedom (DoF) are derived by considering various message exchange scenarios: a multi-user fully-connected Y channel, a two-pair two-way interference channel with the relay, and a two-pair two-way X channel with the relay. Further, considering distributed relays employing a single antenna in the two-way interference channel and the three-user fully-connected Y channel, achievable sum-DoF are also derived in the two-way interference channel and the three-user fully-connected Y channel. A major implication of the derived DoF results is that a relay with multiple antennas or multiple relays employing a single antenna increases the capacity scaling law of the multi-user interference network when multiple directional information flows are considered, even if the networks are fully-connected and all nodes operate in half-duplex. These results reveal that the relay is useful in the multi-way interference network with practical considerations.

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Namyoon Lee, Robert W. Heath Jr. 2013-02-04. Multi-Way Information Exchange Over Completely-Connected Interference Networks with a Multi-Antenna Relay. https://arxiv.org/abs/1302.0749

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