Performance analysis of a distributed resource allocation scheme for D2D communications

TLDR

Device‑to‑device communications underlaying cellular networks enhance capacity, user throughput, and battery life by reusing spectrum, and the network can assist in power, scheduling, and mode selection between direct and cellular links. The authors formulate joint mode selection, scheduling, and power control as an optimization problem solved by a central entity. They further propose a distributed suboptimal scheme for joint mode selection and resource allocation, benchmarking its performance against the centralized optimum. The distributed scheme achieves resource efficiency and user fairness close to the optimal solution.

Abstract

Device-to-device (D2D) communications underlaying a cellular infrastructure has recently been proposed as a means of increasing the cellular capacity, improving the user throughput and extending the battery lifetime of user equipments by facilitating the reuse of spectrum resources between D2D and cellular links. In network assisted D2D communications, when two devices are in the proximity of each other, the network can not only help the devices to set the appropriate transmit power and schedule time and frequency resources but also to determine whether communication should take place via the direct D2D link (D2D mode) or via the cellular base station (cellular mode). In this paper we formulate the joint mode selection, scheduling and power control task as an optimization problem that we first solve assuming the availability of a central entity. We also propose a distributed suboptimal joint mode selection and resource allocation scheme that we benchmark with respect to the centralized optimal solution. We find that the distributed scheme performs close to the optimal scheme both in terms of resource efficiency and user fairness.