Analytical Description of Access Probability and RRA strategy for UAV-Aided Vehicular Applications

In this paper we investigate a scenario where vehicles implement an augmented sensing application and exchange data through Unmanned Aerial Vehicles (UAVs) (a.k.a. drones). The UAVs carry Base Stations (BSs) using multiple antenna beams to cover the ground; they receive data from the cars in the uplink and forward them in the downlink. The objective of this work is to build an analytical framework that provides an expression of the Access Probability, i.e., the probability that the ground user is both covered by one UAV's beam and is assigned enough radio resources to successfully transmit in uplink its traffic demand. We also provide an optimization of the Radio Resources Assignment (RRA) process by comparing two different RRA techniques. Our approach allows to determine the optimal UAV's height and antenna aperture angle as a function of many parameters, including the available bandwidth.