IRS-aided network scheme supports unmanned aerial vehicle communication

Abstract

Intelligent reflecting surface (IRS) and unmanned aerial vehicle (UAV) are forecasted to be extensively used in the forthcoming wireless system. In order to enhance the operational efficiency of UAVs in the urban areas, this paper proposes employing IRS equipped on the rooftop of buildings to create ground-to-air data links between the terrestrial base stations (BSs) and UAVs without any change in the terrestrial infrastructure. An optimization problem aiming to maximize the cumulative achievable data rate (CADR) and minimize the UAV's operational duration via altering the configuration of the IRS network, i.e., the phase profiles and reflecting angles, and the UAV's trajectory has been investigated. To deal with this optimization problem, firstly, we analyze the far-filed radiation pattern of all IRSs to construct the received signal strength (RSS) map over the considered region for a given setup of the activated BS and IRS networks. Then, this map is used to construct the designated BS-IRS-UAV paths (DBIUPs) that are the best paths between neighboring BSs obtained through optimizing the IRS network. Secondly, we develop heuristic algorithms (HAs) to select appropriate DBIUPs to build the optimize UAV's trajectory for any departing and landing positions. The simulation results show that the proposed scheme significantly improves the CADR and reduces the disconnected distance/duration (DD) of considered UAV communication, and the proposed algorithm has a good convergence.