基于SWIPT的吞吐量最优化NOMA全双工中继选择策略

Optimal relay selection for full duplex SWIPT-NOMAsystems with maximal throughput

为了提高5G无线通信系统性能,引入非正交多址接入(NOMA)技术构建了全双工物联网(IoT)中继系统模型。针对无线携能通信(SWIPT)中继系统,该模型考虑中继节点能够捕获源节点、环路自干扰、空闲能量接入点(EAP)的信号能量,使用NOMA技术转发源节点信号与自身信号至不同的目的节点。在该模型基础上,提出了一种基于功率分配协作的SWIPT中继选择策略。该策略基于通信服务质量与源节点发射功率等约束建立问题模型,通过数学变换将原非线性0-1规划问题转换为一对耦合优化问题,基于内部优化问题的最优解解决最优中继选择的外部优化问题,利用最优中继选择算法最大化系统吞吐量。仿真结果表明,所提模型和策略在吞吐量增益方面优于传统的最大最小中继选择方案,并且EAP的考虑能够显著提高系统中断性能。

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.