Orthogonal blinding based schemes for wireless physical
layer security aim to achieve secure communication by
injecting noise into channels orthogonal to the main channel and
corrupting the eavesdropper’s signal reception. These methods,
albeit practical, have been proven vulnerable against multiantenna
eavesdroppers who can filter the message from the noise.
The venerability is rooted in the fact that the main channel state
remains stasis in spite of the noise injection, which allows an
eavesdropper to estimate it promptly via known symbols and filter
out the noise. Our proposed scheme leverages a reconfigurable
antenna for Alice to rapidly change the channel state during
transmission and a compressive sensing based algorithm for her
to predict and cancel the changing effects for Bob. As a result,
the communication between Alice and Bob remains clear, whereas
randomized channel state prevents Eve from launching the knownplaintext
attack. We formally analyze the security of the scheme
against both single and multi-antenna eavesdroppers and identify
its unique anti-eavesdropping properties due to the artificially
created fast changing channel. We conduct extensive simulations
and real-world experiments to evaluate its performance. Empirical
results show that our scheme can suppress Eve’s attack success
rate to the level of random guessing, even if she knows all the
symbols transmitted through other antenna modes.
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Covert Millimeter-Wave Communication via a Dual-Beam Transmitter
In this paper, we investigate covert communication over millimeter-wave (mmWave) frequencies. In particular, a dual-beam mmWave transmitter, comprised of two independent antenna arrays, attempts to reliably communicate to a receiver Bob when hiding the existence of transmission from a warden Willie. In this regard, operating over mmWave bands not only increases the covertness thanks to directional beams, but also increases the transmission data rates given much more available bandwidths and enables ultra-low form factor transceivers due to the lower wavelengths used compared to the conventional radio frequency (RF) counterpart. We assume that the transmitter Alice employs one of its antenna arrays to form a directive beam for transmission to Bob. The other antenna array is used by Alice to generate another beam toward Willie as a jamming signal with its transmit power changing independently from a transmission block to another block. We characterize Willie's detection performance with the optimal detector and the closed-form of its expected value from Alice's perspective. We further derive the closed-form expression for the outage probability of the Alice-Bob link, which enables characterizing the optimal covert rate that can be achieved using the proposed setup. Our results demonstrate the superiority of mmWave covert communication, in terms of covertness and rate, compared to the RF counterpart.
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- NSF-PAR ID:
- 10177964
- Date Published:
- Journal Name:
- 2019 IEEE Global Communications Conference (GLOBECOM)
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/GLOBECOM38437.2019.9013359
