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arXiv · 2202.03899

Covert backscatter communication with directional MIMO

Roberto Di Candia·Saneea Malik·Huseyin Yiğitler·Riku Jäntti
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Abstract

We study a backscatter communication protocol over a AWGN channel, where a transmitter illuminates a tag with a directional multi-antenna. The tag performs load modulation on the signal while hiding its physical presence from a warden. We show that, if the transmitter-to-tag channel is inaccessible to the warden, then $\Theta(n)$ reliable and covert bits can be transmitted over $n$ channel usages. This overcomes the square-root law for covert communication. This paper provides the first evidence for practical implementation of covert backscatter communication, with potential applications in IoT security.

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Roberto Di Candia, Saneea Malik, Huseyin Yiğitler, Riku Jäntti. 2022-02-08. Covert backscatter communication with directional MIMO. https://arxiv.org/abs/2202.03899

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