Optimal UAV Positioning for Terrestrial Users

Unmanned Aerial Vehicles (UAVs) or drones have found a tremendous range of civilian and commercial applications such as precise agriculture, environmental conservation, and search and rescue missions. In this paper, we re-visit the positioning of a low altitude UAV functioning as a relay node to provide connectivity and communication services to ground users who are out of coverage. A new altitude dependant Rician distribution for the air-to-ground channel - derived from propagation physics - is used and its impact on the optimum altitude for network coverage explored via numerical results.