This letter investigates the joint uplink and downlink resource allocation problem, where the non-orthogonal multiple access (NOMA) technology is applied to enhance device-to-device (D2D) communications. In order to maximize the sum data rate of NOMA-enabled D2D groups while guaranteeing the minimum data rate requirements of both cellular users (CUs) and D2D groups, we first design a subcarrier assignment algorithm to assign the downlink and uplink subcarriers for D2D groups, and then transform the problem into a convex optimization to obtain the optimal power allocation. Simulation results demonstrate the remarkable improvement in terms of data rate of D2D groups by using our algorithms.

中文翻译：

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支持 NOMA 的 D2D 通信的联合上行链路和下行链路资源分配

这封信研究了联合上行链路和下行链路资源分配问题，其中应用非正交多址 (NOMA) 技术来增强设备到设备 (D2D) 通信。为了最大化启用 NOMA 的 D2D 组的总数据速率，同时保证蜂窝用户 (CU) 和 D2D 组的最低数据速率要求，我们首先设计了子载波分配算法，为 D2D 组分配下行链路和上行链路子载波，然后将问题转化为凸优化以获得最优功率分配。仿真结果表明，使用我们的算法在 D2D 组的数据速率方面有显着提高。