Soft Frequency Reuse-Based Resource Allocation for D2D Communications Using Both Licensed and Unlicensed Bands

To realize D2D communications, several challenging issues such as the device discovery, spectrum resource allocation, interference management, power control, and communication security remain to be studied. In this paper, we intend to design a resource allocation algorithm which is based on the soft frequency reuse (SFR) scheme, adopts power control, alleviates interference, and uses both the licensed and unlicensed bands for D2D communications. Simulation results demonstrate that the proposed resource allocation algorithm achieves much better performance in terms of system capacity and blocking rate, compared with the conventional allocation scheme that purely uses the licensed band and does not support D2D.