This letter investigates user fairness in wireless powered communication networks (WPCNs) with non-orthogonal multiple access (NOMA) with the aim of maximizing the equal individual data rates. Initially, it is proposed the bisection method to obtain the optimal power allocation coefficients. Then, Lagrange dual-decomposition is considered for evaluating the optimal time-splitting ratio. Next, Newton’s method combined with the sub-gradient method are employed to achieve the optimal solution. In addition, two sub-optimal solutions that provide a good balance between performance and complexity are proposed. Lastly, simulation results are presented to evaluate the performance of the proposed solutions.

中文翻译：

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具有非正交多址接入的无线供电通信网络中的用户公平性

这封信调查了具有非正交多址 (NOMA) 的无线供电通信网络 (WPCN) 中的用户公平性，目的是最大化相等的个人数据速率。最初，提出了二分法来获得最优功率分配系数。然后，考虑拉格朗日对偶分解来评估最佳时间分割比。接下来，采用牛顿法与次梯度法相结合，得到最优解。此外，还提出了两个在性能和复杂性之间提供良好平衡的次优解决方案。最后，仿真结果用于评估所提出的解决方案的性能。