非理想干扰删除下全双工中继NOMA系统的物理层安全性能研究

The imperfect self-interference cancellation in full-duplex cooperative relay networks can make the system performance reduced when the relay forwards signals. We considered the downlink non-ideal full duplex cooperative relay in non-orthogonal multiple access system with eavesdropper (NFCR-E-NOMA), based on which, the impact of self-interference to the NFCR-E-NOMA system was analyzed by outage probabilities and intercept probabilities respectively, and whose exact closed-form expressions were derived. Simulation results show that the self-interference have great influence on the system performance. We also find that there exists optimal relay retransmitting power in the NFCR-E-NOMA system. Moreover, the power allocation ratio also has different influence on the system performance under various transmitting power in base station and relay. In addition, the intercept probability of eavesdropper can be reduced by setting higher data rate under the permission of main link.