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arXiv · 0706.3753

Multiple Access Channels with Generalized Feedback and Confidential Messages

Xiaojun Tang·Ruoheng Liu·Predrag Spasojevic·H. Vincent Poor
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Abstract

This paper considers the problem of secret communication over a multiple access channel with generalized feedback. Two trusted users send independent confidential messages to an intended receiver, in the presence of a passive eavesdropper. In this setting, an active cooperation between two trusted users is enabled through using channel feedback in order to improve the communication efficiency. Based on rate-splitting and decode-and-forward strategies, achievable secrecy rate regions are derived for both discrete memoryless and Gaussian channels. Results show that channel feedback improves the achievable secrecy rates.

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Xiaojun Tang, Ruoheng Liu, Predrag Spasojevic, H. Vincent Poor. 2007-06-26. Multiple Access Channels with Generalized Feedback and Confidential Messages. https://doi.org/10.1109/itw.2007.4313144

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