We consider the multiple-input multiple-output (MIMO) wiretap channel with intersymbol interference (ISI) in which a transmitter (Alice) wishes to securely communicate with a receiver (Bob) in presence of an eavesdropper (Eve). We focus on the practically relevant setting in which there is no channel state information (CSI) at Alice about either of the channels to Bob or Eve, except statistical information about the ISI channels (i.e., Alice only knows the effective number of ISI taps). The key contribution of this work is to show that even with no CSI at Alice, positive secure degrees of freedom (SDoF) are achievable by carefully exploiting a) the heterogeneity of the ISI links to Bob and Eve, and b) the relative number of antennas at all the three terminals. To this end, we propose a novel achievable scheme that carefully mixes information and artificial noise symbols in order to exploit ISI heterogeneity to achieve positive SDoF. To the best of our knowledge, this is the first work to explore the idea of exploiting ISI channel length heterogeneity to achieve positive SDoF for the MIMO wiretap channel with no CSI at the legitimate transmitter.
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ROBin: Known-Plaintext Attack Resistant Orthogonal Blinding via Channel Randomization
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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- Award ID(s):
- 1662487
- PAR ID:
- 10129180
- Date Published:
- Journal Name:
- IEEE INFOCOM 2020
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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