Position-based mode selection and resource allocation for D2D communications underlaying cellular networks

The Device-to-Device (D2D) communication underlaying cellular networks has advantages of improving the spectral utilization, data rate, and energy efficiency. This paper studies a position-based mode selection and resource allocation scheme for D2D communications underlaying cellular networks. With position information available, first an offline channel state information (CSI) retrieval model is introduced. Divide a cell into multiple geographical grids with equal size. Within each grid, each mobile station feedbacks the received strength of signals from eNBs or D2D transmitters in other girds to the connected eNB with location information. The eNB will average the collected signal strengths and further retrieve CSI which will be used to estimate SINR in that grid. Based on this model, an optimization problem is formulated to maximize the sum rate of all users. We propose to employ the differential evolution algorithm to solve this problem to find the optimum mode and resource allocation. Simulations are conducted to verify the advantages of the proposed scheme.