Discrete location-aware resource allocation for underlay device-to-device communications in cellular networks

Device-to-device (D2D) communications underlaying a cellular network is an efficient way to enhance spectral efficiency via resource sharing between D2D and cellular users (CUs). In this study, a discrete location-aware (DLA) interference model for D2D users is presented to allocate cellular resources. The vicinity of a CU is discretised into multiple regions, and the number of active D2D users in each region is constrained to satisfy the CU QoS requirements. Considering the locations of D2D users affecting the interference to CUs and thus the achievable rate, the formulated non-linear 0-1 knapsack resource allocation (RA) problem is divided into two subproblems: (i) the optimal amount of shared resources between the two types of users; (ii) the optimum subset of D2D users which transmit. The conditions of D2D users spatial deployment and resources reuse portion to achieve the solutions of the two subproblems are theoretically derived and proven. Then a DLA-RA algorithm is proposed to solve the corresponding subproblems in both single CU and multiple CUs cases. Extensive simulations results are presented which verify the effectiveness of the proposed DLA interference model and the RA scheme.