On-Demand Deployment of Aerial Base Stations for Coverage Enhancement in Reconfigurable Intelligent Surface-Assisted Cellular Networks on Uneven Terrains

This letter considers the problem of placing aerial base stations (BSs), also known as Unmanned Aerial Vehicle-based BSs (UAV-BSs), to communicate with ground users in cellular networks on uneven terrains. Reconfigurable Intelligent Surfaces (RISs) are deployed on the uneven terrains to assist with the UAV-BSs in eliminating coverage blind spots and extending coverage. Signals are transmitted by the UAV-BSs either directly or via RISs. We develop a new UAV-BS deployment algorithm to maximize coverage. The convergence of the algorithm is analyzed. Simulation results demonstrate the effectiveness of our algorithm.