A Note on the Secrecy Capacity of the Multi-antenna Wiretap Channel

Tie Liu; Shlomo Shamai

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arXiv · 0710.4105

A Note on the Secrecy Capacity of the Multi-antenna Wiretap Channel

Tie Liu·Shlomo Shamai

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Abstract

Recently, the secrecy capacity of the multi-antenna wiretap channel was characterized by Khisti and Wornell [1] using a Sato-like argument. This note presents an alternative characterization using a channel enhancement argument. This characterization relies on an extremal entropy inequality recently proved in the context of multi-antenna broadcast channels, and is directly built on the physical intuition regarding to the optimal transmission strategy in this communication scenario.

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Tie Liu, Shlomo Shamai. 2007-10-22. A Note on the Secrecy Capacity of the Multi-antenna Wiretap Channel. https://arxiv.org/abs/0710.4105

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