Joint Routing and Wireless Resource Allocation in Multihop LTE-D2D Communications

摘要

5G aims to maximize the data rate and to handle the billions of video, voice, data and IoT flows. For this reason, the macro-cells will be very congested and may fail to satisfy the end-users. In this context, data off loading scheme is conceived to route intra-cell traffic among the D2D-enabled user equipments reusing wireless uplink resources and thus increasing the overall spectral efficiency. In this paper, we address the joint routing and OFDMA resource allocation problem in D2D network. To do so, first we formulate the problem as Mixed Integer Linear Programming. The model takes into account factors that limit spectrum reuse as well as other LTE-D2D technology constraints such as: half-duplex operation and contiguity in resource block allocations. Then, we propose a novel scheme named Joint Routing and Wireless allocation in D2D communications (JRN-D2D) which is based on the branch-and-cut algorithm. In order to gauge the effectiveness of our proposal, we implement the standard LTE- D2D protocol stack, including our scheme JRN-D2D, in the NS-3 network simulator. The results obtained are very promising in terms of reliability, ratio of admitted D2D flows and latency in comparison to other basic one-sided optimal strategies including an interference-aware heuristic scheme.