IEEE International Conference on Communications workshops

Non-Coherent Capacity of Secret-Key Agreement with Public Discussion

Anurag Agrawal, Zouheir Rezki, Ashish J. Khisti, Mohamed‐Slim Alouini

Published Jun 1, 2011• 2 citations

Abstract

We study the Rayleigh fading non-coherent capacity of secret-key agreement with public discussion, where neither the sender nor the receivers have access to instantaneous channel state information (CSI) of any channel. We present two results. At high Signal-to-Noise Ratio (SNR), the secret-key capacity is bounded in SNR, regardless of the number of antennas at each terminal. Second, for a system with a single antenna at both the legitimate and the eavesdropper terminals and an arbitrary number of transmit antennas, the secret-key capacity-achieving input distribution is discrete, with a finite number of mass points. Numerically we observe that at low-SNR, the capacity achieving distribution has two mass points with one of them at the origin.

DOI: 10.1109/iccw.2011.5963542

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