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arXiv · 2512.05085

Performance Analysis of Fluid Reconfigurable Intelligent Surface over Covert Communications

Farshad Rostami Ghadi·Masoud Kaveh·Hanjiang Hong·Kai-Kit Wong·Riku Jantti·F. Javier Lopez-Martinez
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Abstract

This paper investigates the impact of the recently proposed concept of fluid reconfigurable intelligent surfaces (FRIS) on covert communications. Specifically, we consider a communication scenario where a legitimate transmitter aims to covertly deliver information to its intended receiver through a planar FRIS, while an adversary attempts to detect whether any transmission is occurring. In this context, we analyze the false alarm (FA) and missed detection (MD) probabilities, and derive a closed-form expression for the covertness outage probability (COP). Furthermore, the success probability is characterized under the optimal detection threshold, providing new insights into the trade-off between covertness and reliable transmission. Numerical results reveal that FRIS provides a clear advantage over fixed-position RIS at low-to-moderate transmit powers by improving reliability and enhancing covertness, while at very high power levels, fixed-position RIS may sustain slightly higher success probability due to reduced leakage toward the adversary.

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Farshad Rostami Ghadi, Masoud Kaveh, Hanjiang Hong, Kai-Kit Wong, Riku Jantti, F. Javier Lopez-Martinez. 2025-12-04. Performance Analysis of Fluid Reconfigurable Intelligent Surface over Covert Communications. https://arxiv.org/abs/2512.05085

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