Physical Layer Security for Cooperative Vehicular Amplify-and-Forward Relay Networks

This paper investigates the secrecy performance of a cooperative vehicular relaying network consisting of a fixed source node, a fixed destination node, an amplify-and-forward (AF) relay vehicle, and a passive eavesdropper vehicle, with the constraints of physical-layer security. We assume that the source-to-relay and relay-to-destination channels are modeled as Rayleigh fading, whereas the relay vehicle-to-eavesdropper vehicle channel is modeled as double-Rayleigh fading. In particular, we derive the tight closed-form expressions for the secrecy outage probability (SOP) and ergodic secrecy capacity (ESC) of the considered system. We also provide an analysis of achievable effective secrecy diversity order. The numerical and simulation results corroborate our analytical findings. Our results demonstrate the impact of channel conditions, and relay and eavesdropper locations on the SOP and ESC performances.