IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC)

Space-time transmissions for wireless secret-key agreement with information-theoretic secrecy

Xiaohua Li, Mo Chen, E. Paul Ratazzi

Published Sep 12, 2005• 26 citations

Abstract

An important building block of the cross-layer network security design is the physical-layer security which addresses problems such as whether the physical-layer can have build-in security and whether physical-layer techniques can assist the upper-layer encryption-based security techniques. This paper provides a positive answer by realizing information-theoretic secrecy with space-time transmissions. While most existing results on information-theoretic secrecy rely on some impractical assumptions, we propose a more practical approach that uses the redundancy of space-time transmissions to create intentional ambiguity to the adversary. Secrecy can be guaranteed even if the adversary has extremely high receiving signal-to-noise ratio. This approach is presented as a new way for secret-key agreement. Simulations in terms of receiving error rate and secret channel capacity are presented.

DOI: 10.1109/spawc.2005.1506252

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