Analysis of Pilot Contamination on the Security Performance of Artificial Noise in MIMO Systems

This paper considers a MIMO communication system that includes a transmitter, a legitimate receiver and an eavesdropper. In such a scenario, the eavesdropper has the knowledge of the pilot and utilizes pilot contamination to reduce the secrecy rate. Firstly, we analyze the effects of malicious pilot contamination on channel estimation. The more the pilot contamination power is, the more the eavesdropping performance enhances, by deducing the secrecy rate and its asymptotic expression in the data transmission phase. Besides, the optimal power allocation scheme for a full-duplex eavesdropper to simultaneously transmit pilot contamination and noise jamming is further studied. Simulation results show that the average secrecy rate with pilot contamination is 0.899bits/s/Hz less than that with noise jamming when the jamming power is 10 mW.