Physical Layer Security in SWIPT Systems with Nonlinear Energy Harvesting Circuits

The discrepancy between the properties of practical nonlinear harvesting circuits and the linear harvesting model conventionally assumed in the literature may cause a severe mismatch for resource allocation, leading to insecure simultaneous wireless information and power transfer (SWIPT) systems. This chapter presents novel beamforming designs enabling secure SWIPT based on a practical nonlinear energy harvesting model. It introduces the adopted channel model and a practical nonlinear RF‐based energy harvesting model. The chapter studies the beamforming design for secure communication in SWIPT systems taking into account the impact of imperfect channel state information (CSI). Simulation results are presented to illustrate the performance of proposed resource allocation algorithm. The chapter aims to maximize the system achievable secrecy rate while guaranteeing a required minimum harvested power at the energy harvesting receivers (ERs).