IRS-Enabled Secure Backscatter Communication Design for V2I MIMO Networks

This paper presents a framework for vehicle-to-infrastructure (V2I) multiple-input multiple-output (MIMO) communication networks enabled by Intelligent Reflecting Surfaces (IRS). The proposed network integrates IRS to exploit transmitting and reflectivity properties for secure transmission in a full-duplex setting. The IRS utilizes random signals from a legitimate vehicle to send roadside information back to the vehicle through backscatter, while a latent eavesdropper with multiple antennas attempts to intercept the backscattered message. To maximize the secrecy rate, we propose an optimization scheme combining block coordinate descent (BCD) and weighted minimum mean-square error (WMMSE) techniques to fine-tune the IRS reflection coefficient and the vehicle’s beamformer. Simulation results highlight the effectiveness of our approach, showing significant improvements in secrecy performance.