Secure Energy-Efficient Wireless Communication with Lens Antenna Array

In this paper, we propose a secure energy-efficient (SEE) transmission scheme with the aid of lens antenna array in millimeter-wave (mmWave) massive multiple-input-multiple-output (massive MIMO) system. In more detail, the lens antenna array is adapted at the transmitter side to reduce energy and information leakage. Based on which, we formulate the considered scenario as an optimization problem to maximize SEE by designing the beamforming at the transmitter. Besides, we also obtain the expression of the maximum transmission distance between the transmitter and the desired user. The simulation results show that the proposed scheme can achieve secure transmission with a high value of SEE. Additionally, the maximum secrecy distance and the value of SEE increase when the number of transmit antenna increases.