In this paper, we analyze the performance of cooperative power-domain non-orthogonal multiple access systems (PD-NOMA) for multiple users in a multiple energy-harvesting (EH) relay network with unreliable backhaul links over Nakagami-m fading channels. In the proposed system, multi-destination users are allocated various powers and communicate with the best transmitter (Tx) via the best relay. EH relay employs a power-splitting relaying (PSR) architecture and an amplify-and-forward (AF) protocol. To evaluate the performance of each user and the overall system, closed-form analytical expressions for the outage probability (OP) and throughput over Nakagami-m fading channels are derived. Moreover, Monte Carlo simulations are used to verify the accuracy of the analytical results. In addition, the effects of key parameters of the system, such as the shape factor of the Nakagami-m channel model, power allocation, EH efficiency, power splitting ratio, and the number of relay nodes, on both the outage probability and throughput for multiple NOMA users are analyzed. These results show that the proposed PD-NOMA system offers better user-fairness in comparison with the conventional orthogonal multiple-access (OMA) system.

在本文中，我们分析了多用户合作功率域非正交多接入系统（PD-NOMA）在多能量采集（EH）中继网络拥有超过Nakagami-可靠回程链路的性能米衰落信道。在提出的系统中，为多目标用户分配了各种功率，并通过最佳中继与最佳发射器（Tx）进行通信。EH中继采用功率分配中继（PSR）架构和放大转发（AF）协议。为了评估每个用户的性能和整个系统，用于中断概率的闭合形式的解析表达式（OP）和吞吐量较Nakagami-米推导衰落信道。此外，使用蒙特卡洛模拟来验证分析结果的准确性。此外，该系统的关键参数，如Nakagami-的形状因子的影响米信道模型，功率分配，EH效率，功率分光比，以及中继节点的数目，在中断概率都和吞吐量分析了多个NOMA用户。这些结果表明，与传统的正交多址（OMA）系统相比，所提出的PD-NOMA系统具有更好的用户公平性。