Physical layer security for SWIPT-NOMA system in presence of randomly located eavesdroppers

Abstract

The combination of non-orthogonal multiple access (NOMA) and simultaneous wireless information and power transfer (SWIPT) technologies can improve spectrum efficiency of wireless system and solve the power supply problem of user nodes.However, when energy-harvesting receivers want to maliciously eavesdrop on confidential information sent by the base station, the information security transmission of SWIPT-NOMA system will be threatened.To enhance its physical layer security (PLS) performance, the PLS model of SWIPT-NOMA system with transmit antenna selection and power split strategies was proposed.When the spatial location randomly distributed energy-harvesting receivers obey the Poisson point process, the approximate expressions for the secrecy outage probability and non-zero secrecy capacity probability of SWIPT-NOMA system were derived by using the spatial Poisson probability generation function.Numerical and simulation results verify the accuracy of the expressions.The above expressions can also be used to study the influence of eavesdropper density, the distance between the base station and the far and near information receivers, the number of transmitting antennas and the power split factor on PLS performance of SWIPT-NOMA system.

Keywords

• non-orthogonal multiple access;simultaneous wireless information and power transfer;physical layer security;Poisson point process;secrecy outage probability