Power Adaptation for Improving the Performance of Time Switching SWIPT-Based Full-Duplex Cooperative NOMA Network

This letter investigates an adaptive power allocation (APA) scheme for the simultaneous wireless information and power transfer (SWIPT) enabled full duplex (FD) cooperative non-orthogonal multiple access (NOMA) network under time switching (TS) protocol. The proposed APA involves the joint design of power allocation coefficient at the base station and the TS factor at the relay. We derive expressions for the outage probabilities (OP) experienced by the downlink users under APA as well as fixed power allocation (FPA) strategies, considering imperfect successive interference cancellation. By providing the asymptotic OP analysis, we establish that the proposed APA scheme: (i) resolves the zero diversity order problem inherent in FD-NOMA systems under FPA and (ii) significantly improves outage and throughput performance of SWIPT enabled FD-NOMA systems.