Joint Fair Resource Allocation of D2D Communication Underlaying Downlink Cellular System With Imperfect CSI

Device-to-device (D2D) communication as a feasible technique can improve the system efficiency without fixed infrastructures. In this paper, we focus on the fair resource allocation of D2D communication underlaying cellular system with channel uncertainty and propose a joint resource allocation policy about the resource block assignment and power allocation among the D2D and cellular users (CUs). We formulate a nominal optimization problem to improve the sum rate of the D2D system and guarantee the quality of service of the CUs. Moreover, taking the uncertainty of the channel state information into consideration, we employ the robust optimization theory to define the uncertainty and construct a robust optimization problem with uncertain parameters in both objective function and constraints. To facilitate the solution, we segment the robust optimization problem into two subproblems. Furthermore, we utilize the chance constraint approach to cut down the cost of the robustness and achieve a tradeoff between the robustness and the optimality. An insight into the influence of the protection function to the achievable D2D sum rate is obtained by sensitivity analysis. In addition, the effect of the robustness on the D2D sum rate with different channel uncertainty is presented in the simulation, and a rate tradeoff between the D2D users and CUs is achieved by the proposed policy.