Secure Communication for Millimeter-Wave Systems with Randomly Located Non-Colluding Eavesdroppers

Communication over millimeter wave (mmWave) regimes has been emerged as a new approach to provide the data traffic requirement in 5G communication network. In this contribution, we proceed physical layer security (PLS) in mmWave systems, where an untrusted amplify-and-forward (AF) relay and passive eavesdroppers (Eves) are in the system model. The untrusted relay cooperates for the source-to-destination communication, while it may intercept the secrecy message. For this network, cooperative jamming by both the source and destination is suggested for network protection. By the goal of maximizing the instantaneous secrecy rate, a new solution is proposed for the optimal power allocation (OPA) under the scenario of non-colluding Eves (NCE). Then a new formula is achieved for the ergodic secrecy rate (ESR) as a secrecy metric over mmWave fading channels by considering the effect of blockage with a model that includes the line-of-sight (LoS) and non-line-of-sight (NLoS) paths. Our simulation results illustrate that the ESR of the proposed OPA strategy is increased with respect to the other schemes.