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

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 نشر من قبل Tie Liu
 تاريخ النشر 2007
  مجال البحث الهندسة المعلوماتية
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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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