Multiple UAV deployment optimization for maximising communication coverage over wide areas

This paper presents an efficient approach for finding the optimal 3D deployment locations of multiple UAV base stations, to maximize the probability of connection for users uniformly distributed over a wide area. We consider covering a two-dimensional built urban environment with UAVs arranged in a regular equilateral triangle structure. We propose to provide a degree of overlapping coverage between the UAVs to provide diversity to UEs to overcome blockage from buildings. We optimize the distance between UAV flying locations as well as their flying height. Our analysis approach is based on an accurate two-tier connectivity model. We demonstrate that our deployment approach outperforms existing approaches that adopt average path loss models. We achieve a 10-20% improvement in connectivity performance.