Secrecy Performance Analysis On Relay-Assisted Millimeter Wave Networks

The use of relay can expand the coverage of millimeter wave (mmWave) signals, whereas it can be vulnerable to eavesdropping attacks due to the additional transmission from source to relay. In this paper, we consider the transmission of a confidential message from source to destination in the relay-assisted mmWave networks in the presence of randomly distributed eavesdroppers, and we derive the expressions of secure connectivity probability for both non-colluding and colluding eavesdroppers scenarios. The simulation results verify our derivations and show that the secrecy performance of relay transmission is better than direct transmission when the relay locates in an oval-like area, and the optimal location will move towards destination node when the antenna gain of source node increases.