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arXiv · 2504.13666

Physical Layer Authentication With Colored RIS in Visible Light Communications

Besra Cetindere Vela·Serkan Vela·Stefano Tomasin
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Abstract

We study a visible light communication (VLC) system that employs a colored reconfigurable intelligent surface (CRIS) based on dichroic mirrors that reflect light at tunable frequencies. A verifier can use the CRIS to authenticate transmissions by comparing received multicolor power profiles with expected patterns. Four CRIS configuration strategies are evaluated: a deterministic cyclic pattern, static random reflectance, dynamic random reflectance, and dynamic random permutation of fixed profiles. Randomized configurations, especially dynamic ones, achieve superior authentication, enabling a novel challenge-response physical-layer authentication scheme over CRIS.

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Besra Cetindere Vela, Serkan Vela, Stefano Tomasin. 2025-04-18. Physical Layer Authentication With Colored RIS in Visible Light Communications. https://arxiv.org/abs/2504.13666

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