Physical-Layer Security for RIS-V2V Networks With Different Eavesdropper Locations

Due to the high mobility of vehicles and the Doppler effect, the applications of autonomous driving face a great challenge. Moreover, with the massive number of vehicles connected to networks, existing network resources are experiencing bottlenecks. To overcome these urgent issues, this work aims to study the physical layer security (PLS) for the reconfigurable intelligent surfaces (RIS) assisted Vehicle-to-Vehicle (V2V) communications, considering different eavesdropper locations. We introduce two different eavesdropping models: the one is eavesdropper located near to the source vehicle, who will be wiretapped by the direct downlink; the other one is that eavesdropper is located near the receiving vehicle and in the beamforming region, hence it will wiretap the information from the reflected link of RIS. Specifically, the upper bound for security capacity and the approximate security outage probability (SOP) of such two scenarios are respectively derived, under the double Rayleigh fading channels. By means of the numerical and simulation results, it shows that the security performance of the PLS of RIS-assisted communications is significantly improved with increasing of the transmit power, distance between nodes, number of RIS elements and secrecy capacity threshold. The analysis underscores the potential of optimizing RIS’s location and size to significantly bolster the wireless communication quality in Internet-of-Vehicles (IoV) environments. This integration not only mitigates the challenges posed by high mobility and Doppler effects but also effectively counters eavesdropping attempts, ensuring robust security in IoV networks.