Artificial Noise-Assisted Beamforming and Power Allocation for Secure D2D-Enabled V2V Communications

In this article, we propose a physical layer security (PLS) scheme to secure vehicle-to-vehicle (V2V) communications, where vehicles share spectrum resources with cellular users via underlaying device-to-device (D2D) technologies. Existing PLS-assisted V2V communication schemes neglect the issue of the unknown eavesdropper's instantaneous channel state information (CSI), and the management of spectrum resource reuse-incurred interference should be enhanced. Here, we design an artificial noise (AN)-assisted beamforming scheme to protect the V2V communications that does not require the eavesdropper's instantaneous CSI. Especially, the spectrum resource reuse-incurred interference can be eliminated by detection methods. Also, we deduce the expression of secrecy outage probability as the security metric, and minimize the secrecy outage probability via power allocation. The simulations demonstrate that the proposed scheme can reduce the secrecy outage probability compared to conventional methods.