Downlink resource reuse for Device-to-Device communication underlaying cellular networks using a generalized Knapsack framework

In this paper, we investigate the resource allocation problem to improve the performance of Device-to-Device (D2D) communications underlaying downlink cellular networks. We aim to optimize the sum-rate of D2D communications while fulfilling Quality of Service (QoS) requirements of prioritized cellular network. To achieve this, we formulate the problem as a Knapsack utility maximization problem for each cellular resource and generalize a recursive algorithm based on dynamic programming as a solution. In order to improve the spectrum utilization we exploit multiuser diversity in which, a cellular frequency resource is allowed to be shared by multiple D2D users (DUs) and a DU is allowed to reuse more than one frequency resource. The simulation results demonstrate that the proposed scheme leads to near-optimal performance on D2D sum-rate.