A Combined Cable-Connected RSU and UAV-Assisted RSU Deployment Strategy in V2I Communication

Vehicle-to-infrastructure (V2I) communication enables vehicles to acquire surrounding traffic information in real time, which significantly improves the driving safety and comfort. The cable-connected roadside unit (c-RSU) with high communication capability and large communication range plays an indispensable role in V2I communication. Meanwhile, unmanned aerial vehicle (UAV) technology has developed rapidly. In terms of its unique mobility and flexibility, the UAV-assisted RSU (u-RSU) can dynamically adjust its position according to the traffic density and emergencies. So the u-RSU can be a reliable supplement to the ground RSU in V2I communication. In this paper, a combined c-RSU and u-RSU deployment strategy is proposed to achieve the maximal effective traffic coverage ratio (ETCR) under a given tough budget bound. To solve this problem, we introduce a two layer improved greedy algorithm (TLIGA). Within TLIGA, the first layer greedy algorithm embedded with the improved Kruskal algorithm is used to deploy c-RSUs and cable, while the second layer improved greedy algorithm is used to determine the optimal number of u-RSUs and their flight strategy. Simulation results show that compared with the existing methods the proposed algorithm TLIGA can significantly increase ETCR.