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arXiv · 0906.3821

Relaying Simultaneous Multicast Messages

D. Gunduz·O. Simeone·A. Goldsmith·H. V. Poor·S. Shamai
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Abstract

The problem of multicasting multiple messages with the help of a relay, which may also have an independent message of its own to multicast, is considered. As a first step to address this general model, referred to as the compound multiple access channel with a relay (cMACr), the capacity region of the multiple access channel with a "cognitive" relay is characterized, including the cases of partial and rate-limited cognition. Achievable rate regions for the cMACr model are then presented based on decode-and-forward (DF) and compress-and-forward (CF) relaying strategies. Moreover, an outer bound is derived for the special case in which each transmitter has a direct link to one of the receivers while the connection to the other receiver is enabled only through the relay terminal. Numerical results for the Gaussian channel are also provided.

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D. Gunduz, O. Simeone, A. Goldsmith, H. V. Poor, S. Shamai. 2009-06-20. Relaying Simultaneous Multicast Messages. https://doi.org/10.1109/itwnit.2009.5158539

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