This paper proposes a system EE (energy efficiency) optimization algorithm based on OPS (On-off Power Splitting) strategy for SWIPT (Simultaneous Wireless Information and Power Transfer) two-way relay assisted CR-NOMA (Cognitive Radio Non-Orthogonal Multiple Access) network. The system capacity expression of the secondary users with the OPS strategy is derived. Under the constraints of harvested energy and quality of service (QoS) of the users, the optimization problem with the goal of maximizing energy efficiency is constructed. In this paper, the NP-Hard problem is transformed into three subproblems about relay power, NOMA coefficient, and segmentation coefficient, which are solved by golden section algorithm, monotonicity decision function, and genetic algorithm. The simulation results show that compared with the PS (Power Splitting) and TS (Time Switching) strategies, the OPS strategy can significantly improve the transmission energy efficiency of the system.

中文翻译：

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基于SWIPT的CR-NOMA系统能效优化算法

本文提出了一种基于OPS（开-关功率分配）策略的系统EE（能源效率）优化算法，用于SWIPT（同时无线信息和功率传输）双向中继辅助CR-NOMA（认知无线电非正交多路访问）网络。推导了采用OPS策略的二级用户的系统容量表达式。在能量采集和用户服务质量（QoS）的约束下，构建了以能量效率最大化为目标的优化问题。本文将NP-Hard问题转化为关于继电功率，NOMA系数和分割系数的三个子问题，分别用黄金分割算法，单调性决策函数和遗传算法解决。