PHYSICAL LAYER SECURITY GAME WITH FULL-DUPLEX PROACTIVE EAVESDROPPER

Self-interference cancellation technologies enable full-duplex operation at the eavesdropper. In addition to wiretapping, the eavesdropper simultaneously tries to reduce the secrecy rate of the illegitimate transmitter-receiver pair by jamming its receiver. On the other hand, the transmitter-receiver pair aims to increase its secrecy rate. To examine the power decision processes between the transmitter and the eavesdropper, we propose a novel physical layer security game in the wiretap channel, where the eavesdropper operates in a full-duplex mode. To analyse the game outcome, a distributed learning algorithm is adopted to achieve the mixed-strategy Nash equilibrium. Based on the equilibrium, we provide a switch strategy for the eavesdropper to determine the optimal operation mode between the full-duplex and half-duplex, depending on its location and self-interference. Numerical results show that the switch strategy improves the eavesdropper's performance in the sense of decreasing the secrecy rate.