Tongxin xuebao (May 2021)
Optimal relay selection for full duplex SWIPT-NOMA systems with maximal throughput
Abstract
To improve the performance of 5G communication system, a full duplex Internet of things (IoT) relay system model was built by introducing the non-orthogonal multi-access (NOMA) technology.For the relay system of simultaneous wireless information and power transfer (SWIPT), it was considered that the relay node can harvest the energy of the source node, the self-interference signal of the loop channel and the free energy access point (EAP), and NOMA technology was used to forward the source node signal and its own signal to different destination nodes.Based on the model, a power distribution collaboration SWIPT relay selection strategy was proposed to optimize system throughput.Firstly, the problem model was established based on the constraints of communication quality of service and transmission power of source nodes.And then, the original nonlinear 0-1 programming problem was converted into a pair of coupling optimization problem by mathematical transformation, and the optimal relay selection of outer optimization problem was solved based on the optimal solution of the internal optimization problem.Finally, an optimal relay selection algorithm was used to maximize system throughput.Simulation results show that the proposed model and strategy are superior to the traditional maximum-minimum relay selection schemes in terms of throughput gain, and the consideration of EAP can significantly improve the interrupt performance.
