Average Secrecy Capacity Performance Analysis for SWIPT-Based SIMO Underlay Cognitive Radio

We address the physical layer security (PHY-security) for an underlay single-input multiple-output (SIMO) cognitive radio network using simultaneous wireless information and power transfer (SWIPT). The considered system model is composed of one primary receiver, one secondary transceiver, and one energy harvesting receiver that may potentially be an eavesdropper. First, the closed-form analytic expression of the average secrecy capacity (ASC) of the considered network is derived. Second, we analyze the network's achievable ASC under Rayleigh fading assumption for all underlying channels. Our results indicate that ASC performance is improved by reducing the number of deployed antennas at the energy receiver or by increasing the number of antennas deployed at the information receiver.