Energy-Efficient Resource Allocation in D2D Underlaid Cellular Uplinks

In this letter, we study the joint channel allocation and power control problem to maximize the energy efficiency (EE) of device-to-device (D2D) links in a D2D underlaid cellular network. Due to the location dispersion of D2D pairs and short-distance D2D transmission, it should be preferred that multiple D2D pairs can simultaneously share the resource with cellular users (CUs). To address the nonconvexity of the EE maximization problem, we divide the original problem into two subproblems and propose an iterative algorithm with low complexity to solve it. Simulation results show that the proposed algorithm converges rapidly and the EE of D2D links can be significantly improved compared with existing methods especially for an increasing number of CUs.