Towards the Secrecy Capacity of the Gaussian MIMO Wire-tap Channel: The 2-2-1 Channel

Shabnam Shafiee; Nan Liu; Sennur Ulukus

doi:10.1109/tit.2009.2025549

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arXiv · 0709.3541

Towards the Secrecy Capacity of the Gaussian MIMO Wire-tap Channel: The 2-2-1 Channel

Shabnam Shafiee·Nan Liu·Sennur Ulukus

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Abstract

We find the secrecy capacity of the 2-2-1 Gaussian MIMO wire-tap channel, which consists of a transmitter and a receiver with two antennas each, and an eavesdropper with a single antenna. We determine the secrecy capacity of this channel by proposing an achievable scheme and then developing a tight upper bound that meets the proposed achievable secrecy rate. We show that, for this channel, Gaussian signalling in the form of beam-forming is optimal, and no pre-processing of information is necessary.

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Shabnam Shafiee, Nan Liu, Sennur Ulukus. 2007-09-21. Towards the Secrecy Capacity of the Gaussian MIMO Wire-tap Channel: The 2-2-1 Channel. https://doi.org/10.1109/tit.2009.2025549

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