Detecting active eavesdropper in large-scale antenna systems over Rician fading channels

摘要

Physical layer security is efficient in improving the security of transmission in wireless communications. It is effective in relaxing the complexity of the required cryptographic technologies. In this paper, we propose two detection schemes of an active eavesdropper in the physical layer of wireless communications. The system consists of a multi-antenna base station, a single-antenna legitimate user, and a single-antenna active eavesdropper. The large number of antennas at the base station is arranged as a planar array. It is assumed that the system is time division duplex (TDD) and the channels are of Rician distribution. The proposed two detection schemes are used to detect the eavesdropper by the base station and legitimate user, respectively. In both methods, the statistical characteristics of the received signals are analyzed and two test-statistics are constructed to detect the eavesdropper. The performances of the two methods are also analyzed. Simulation results show that both approaches are effective in detecting the active eavesdropper.