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arXiv · 2408.14969

Secrecy Performance Analysis of RIS-Aided Fluid Antenna Systems

Farshad Rostami Ghadi·Kai-Kit Wong·Masoud Kaveh·F. Javier Lopez-Martinez·Wee Kiat New·Hao Xu
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Abstract

This paper examines the impact of emerging fluid antenna systems (FAS) on reconfigurable intelligent surface (RIS)-aided secure communications. Specifically, we consider a classic wiretap channel, where a fixed-antenna transmitter sends confidential information to an FAS-equipped legitimate user with the help of an RIS, while an FAS-equipped eavesdropper attempts to decode the message. To evaluate the proposed wireless scenario, we first introduce the cumulative distribution function (CDF) and probability density function (PDF) of the signal-to-noise ratio (SNR) at each node, using the central limit theorem and the Gaussian copula function. We then derive a compact analytical expression for the secrecy outage probability (SOP). Our numerical results reveal how the incorporation of FAS and RIS can significantly enhance the performance of secure communications.

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Farshad Rostami Ghadi, Kai-Kit Wong, Masoud Kaveh, F. Javier Lopez-Martinez, Wee Kiat New, Hao Xu. 2024-08-27. Secrecy Performance Analysis of RIS-Aided Fluid Antenna Systems. https://arxiv.org/abs/2408.14969

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