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arXiv · 1106.1969

The Capacity Region of Multiway Relay Channels Over Finite Fields with Full Data Exchange

Lawrence Ong·Sarah J. Johnson·Christopher M. Kellett
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Abstract

The multi-way relay channel is a multicast network where L users exchange data through a relay. In this paper, the capacity region of a class of multi-way relay channels is derived, where the channel inputs and outputs take values over finite fields. The cut-set upper bound to the capacity region is derived and is shown to be achievable by our proposed functional-decode-forward coding strategy. More specifically, for the general case where the users can transmit at possibly different rates, functional-decode-forward, combined with rate splitting and joint source-channel decoding, is proved to achieve the capacity region; while for the case where all users transmit at a common rate, rate splitting and joint source-channel decoding are not required to achieve the capacity. That the capacity-achieving coding strategies do not utilize the users' received signals in the users' encoding functions implies that feedback does not increase the capacity region of this class of multi-way relay channels.

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Lawrence Ong, Sarah J. Johnson, Christopher M. Kellett. 2011-06-10. The Capacity Region of Multiway Relay Channels Over Finite Fields with Full Data Exchange. https://doi.org/10.1109/tit.2011.2120010

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