In recent years, with the explosive growth of data traffic, communication base stations (BSs) need to serve more and more users. Offloading traffic from BSs has become an efficient way to reduce the burden on BSs. Device-to-Device (D2D) communications have emerged to improve spectrum utilization by reusing the frequency spectrum of the cellular frequency band. In the general environment, Heterogeneous Cellular Networks (HCNs) including millimeter wave (mm-wave) have appeared. Since the D2D link allows to share of spectrum resources with the cellular user, it will bring potential interference to the cellular user. Fortunately, an emerging technology called Reconfigurable Intelligent Surface (RIS) can mitigate the severe interference caused by D2D links by shaping the incident beam and improving the multipath phase shift. In this paper, we study the resource allocation scheme to maximize the system sum rate, in the RISassisted single-cell heterogeneous D2D communication scenario. To solve the Block Coordinate Descent (BCD) problem, the problem of maximizing the sum rate is decomposed into three sub-problems. The resource allocation sub-problem is solved by a coalitional game method based on the game theory. The power allocation problem of the coalition converts the concave function into a convex optimization by mathematical transformation. The problem is solved by the gradient descent method. The local search method is adopted to find the optimum for the phase conversion problem. Then iterate until the difference of sum rate is less than the threshold. The simulation results show that the designed algorithm is superior to other benchmark schemes in the literature.

翻译：近年来，随着数据流量的爆炸性增长，通信基站需服务的用户数量持续攀升。将流量从基站分流已成为减轻其负载的有效途径。设备到设备通信通过复用蜂窝频段的频谱资源，有效提升了频谱利用率。在通用环境中，包含毫米波的异构蜂窝网络已逐步出现。由于D2D链路允许与蜂窝用户共享频谱资源，这将给蜂窝用户带来潜在干扰。幸运的是，一种名为可重构智能表面的新兴技术可通过调控入射波束并优化多径相位偏移，有效抑制D2D链路引发的严重干扰。本文研究了RIS辅助单小区异构D2D通信场景下最大化系统和速率的资源分配方案。为求解块坐标下降问题，将和速率最大化问题分解为三个子问题：通过基于博弈论的联盟博弈方法解决资源分配子问题；将联盟内的功率分配问题通过数学变换转化为凸优化问题，并采用梯度下降法求解；针对相位转换问题采用局部搜索方法寻求最优解。迭代过程持续进行直至和速率差值低于阈值。仿真结果表明，所设计算法优于文献中的其他基准方案。