MILP-Based Radio Resource Assignment for Device to Device Communications

In this paper we consider an LTE macrocell where cellular users can be selected to act in Device-to-Device (D2D) mode to optimise spectrum efficiency and resource utilisation. We propose a D2D mode selection method based on a Mixed Integer Linear Program, accounting for the signal-to-noise ratio among nodes and the user sociality. This work analyses the benefit of D2D considering also interference and evaluating whether it is better to assign uplink or downlink radio resources for the D2D communication. Simulations show improvements in terms of network throughput, with respect to a case where D2D links are not used, even accounting for interference and considering half-duplex communication. It is also shown how the choice of a well designed radio resource assignment strategy has a strong impact on the interference created in the network by the activation of D2D links.