The combination of device-to-device (D2D) communication with non-orthogonal multiple access (NOMA) is an efficient solution to enhance the spectral efficiency and connection density of beyond fifth-generation cellular networks. In the paper, we optimize the power allocation of NOMA-enabled D2D communication. In particular, we formulate sum data rate maximization problem subject to the quality of services of cellular user and transmit power of D2D communication. To obtain the efficient solution, we exploit dual theory by using sub-gradient method to solve the dual variables. To gauge the performance of the proposed optimal power allocation scheme, the results are also compared with average power allocation schemes and orthogonal multiple access schemes. The simulation results unveil that the proposed optimization scheme significantly improve the data rate of D2D communication compared to the benchmark schemes.

设备到设备（D2D）通信与非正交多址访问（NOMA）的结合是一种有效的解决方案，可以增强第五代蜂窝网络以外的频谱效率和连接密度。在本文中，我们优化了启用NOMA的D2D通信的功率分配。特别是，我们根据蜂窝用户的服务质量和D2D通信的发送功率来制定总数据速率最大化问题。为了获得有效的解决方案，我们通过使用次梯度法来利用对偶理论来求解对偶变量。为了评估所提出的最佳功率分配方案的性能，还将结果与平均功率分配方案和正交多址方案进行了比较。