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arXiv · 1404.2081

Simultaneous Diagonalization: On the DoF Region of the K-user MIMO Multi-way Relay Channel

Anas Chaaban·Karlheinz Ochs·Aydin Sezgin
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Abstract

The K-user MIMO Y-channel consisting of K users which want to exchange messages among each other via a common relay node is studied in this paper. A transmission strategy based on channel diagonalization using zero-forcing beam-forming is proposed. This strategy is then combined with signal-space alignment for network-coding, and the achievable degrees-of-freedom region is derived. A new degrees-of-freedom outer bound is also derived and it is shown that the proposed strategy achieves this outer bound if the users have more antennas than the relay.

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Anas Chaaban, Karlheinz Ochs, Aydin Sezgin. 2014-04-08. Simultaneous Diagonalization: On the DoF Region of the K-user MIMO Multi-way Relay Channel. https://arxiv.org/abs/1404.2081

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