A Social-Aware Virtual MAC Protocol for Energy-Efficient D2D Communications Underlying Heterogeneous Cellular Networks

In this paper, a social-aware virtual medium access control (SV-MAC) is devised to integrate virtualization and social awareness to D2D communications underlying heterogeneous cellular networks. SV-MAC is a converged network layer. Through SV-MAC, heterogeneous networks can be unified in a single protocol stack, providing a common abstraction for users and mobile network operators (MNOs) to share their network resources. Leveraging users' social information, SV-MAC can realize social-aware D2D discovery, association, and resource allocation for improved D2D communication efficiency. In order to validate the advantages of the proposed SV-MAC protocol, we study the cellular and D2D resource allocation problems under the SV-MAC protocol. The problems are formulated as maximizing the cellular and D2D energy efficiency (EE). The cellular resource allocation problem is first solved considering its priority to D2D users. The resource allocation problem for D2D users is solved after cellular users to control the D2D-to-cellular interference within a tolerable threshold. In the simulation, we introduce real mobile user traces to simulate the user social information. Simulation results show that the proposed SV-MAC resource allocation schemes obtain a beneficial EE improvement comparing with conventional schemes.