IRS-VLC physical layer security scheme: a dual-strategy against eavesdropping and attacks

This study introduces a comprehensive physical layer security (PLS) scheme in visible light communication (VLC) systems using non-Lambertian beamforming and intelligent reflecting surfaces (IRSs). It withstands eavesdropping and attacks to secure indoor VLCs, even with imperfect channel state information (CSI). In conventional VLC systems, the required illuminance maintaining normal communication is about 80 lux. The proposed scheme reduces the illuminance in a potential eavesdropping area to 5.2 lux by manipulating the direction and intensity of the optical signals, which leads to eavesdropping failure. Meanwhile, the proposed scheme is jamming-resistant. Simulations demonstrate that the system adopting the proposed security scheme has a SINR of 40.32 dB with jamming attacks, compared to 26.13 dB in typical VLC systems, so the resisting interference ability is improved by 54%. Eavesdropping resistance and attack resilience make VLC security in sensitive contexts more robust.