Covert Capacity of Non-Coherent Rayleigh-Fading Channels

Mehrdad Tahmasbi; Anne Savard; Matthieu R. Bloch

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arXiv · 1810.07687

Covert Capacity of Non-Coherent Rayleigh-Fading Channels

Mehrdad Tahmasbi·Anne Savard·Matthieu R. Bloch

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Abstract

The covert capacity is characterized for a non-coherent fast Rayleigh-fading wireless channel, in which a legitimate user wishes to communicate reliably with a legitimate receiver while escaping detection from a warden. It is shown that the covert capacity is achieved with an amplitude-constrained input distribution that consists of a finite number of mass points including one at zero and numerically tractable bounds are provided. It is also conjectured that distributions with two mass points in fixed locations are optimal.

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Mehrdad Tahmasbi, Anne Savard, Matthieu R. Bloch. 2018-10-17. Covert Capacity of Non-Coherent Rayleigh-Fading Channels. https://arxiv.org/abs/1810.07687

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