IEEE Wireless Communications Letters

Optimal Pilot Length for Key Generation in Correlated Wireless Channels

Danqi Li, Shihao Yan, Jia Zhang, Jiande Sun, Feng Shu

Published Aug 16, 2024• 0 citations

Abstract

This letter examines the optimal pilot length for key generation in correlated wireless channels. We first deduce the secret key capacity as a function of the pilot length N and other system parameters. Then, derive two fixed-point equations to identify the optimal N with and without an eavesdropper. Our analysis and numerical results confirm the existence of the optimal N that maximizes the secret key capacity, and both results for optimal N are consistent. Furthermore, the optimal N generally decreases with average signal-to-noise ratio and maximum Doppler shift. Our examination can provide useful guidelines in designing practical key generation systems.

DOI: 10.1109/lwc.2024.3444821

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