A novel resource allocation scheme for D2D communication underlaying small cell networks

Small cell deployment and device-to-device (D2D) communications can significantly enhance the system performance by offloading core network traffic and reducing the overall energy consumption, especially in the dense network. However, the interference emerging in it is severe and complicate. In this paper, we develop a model aiming to achieve the maximal system throughput and simultaneously ensuring the quality of service (QoS) of each user accessed into the heterogeneous network (HetNet). Further, we solve the optimization formulation in three steps. First, we find a feasible radio resource allocation profile of small cell networks without D2D communications. Then we optimize the D2D resources based on convex optimization theory. Finally, we get the maximal HetNet capacity according to the theoretical analysis by comparing different resource allocation profiles of small cell networks. Simulation results demonstrate that our approach is feasible and effective to achieve the maximal HetNet throughput simultaneously ensuring each user´s QoS.