A QoS-based resource allocation algorithm for D2D communication underlaying cellular networks

D2D (Device-to-Device) communication, which can decrease the power and enhance spectrum efficiency when sharing the resources of cellular networks, has caused a lot of attention. However, the performance of cellular networks decreases for the interference between cellular users and D2D users. In this paper, we put forward a channel allocation and power control algorithm, which can maximize the capacity of total D2D users under the conditions of guaranteeing QoS of users and limited transmission power of users. First, we allocate channels to D2D users according to the minimum SINR demand of D2D users. And then, the transmission power of each D2D pair and each cellular user are optimized with Lagrange multiplier method. Meanwhile we calculate the capacity of D2D users by optimal transmission power. Simulation results show that the capacity of D2D users improves with the proposed algorithm in a certain extent.