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arXiv · 2604.12156

Impact of Position Uncertainty on the Secrecy Performance of Pinching Antenna Systems

Saeid Pakravan·Imene Trigui·Wessam Ajib·Wei-Ping Zhu
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Abstract

This paper investigates the secrecy performance of pinching-antenna systems (PAS) under practical pinching-position activation uncertainty. By dynamically selecting the radiation point along a dielectric waveguide, PAS enables low-cost spatial reconfigurability and enhanced secure transmission. Unlike existing studies that assume ideal activation control, we account for spatial inaccuracies caused by hardware limitations and environmental perturbations, which induce statistical dependence between the legitimate and eavesdropping channels. To characterize this uncertainty-induced dependence, PAS-specific marginal signal-to-noise ratio (SNR) distributions are derived, and a Gaussian copula is employed as a tractable representation of the resulting joint SNR distribution, enabling the derivation of approximate expressions for the secrecy outage probability. Simulation results validate the theoretical findings and demonstrate that PAS retains robust secrecy performance compared with conventional fixed-antenna systems, even in the presence of activation uncertainty.

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Saeid Pakravan, Imene Trigui, Wessam Ajib, Wei-Ping Zhu. 2026-04-14. Impact of Position Uncertainty on the Secrecy Performance of Pinching Antenna Systems. https://arxiv.org/abs/2604.12156

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