Abstract

To meet the growing mobility needs in intra-city transportation, urban air mobility (UAM) has been proposed in which vertical takeoff and landing (VTOL) aircraft are used to provide on-demand service. In UAM, an aircraft can operate in the corridors, i.e., the designated airspace, that link the aerodromes, thus avoiding the use of complex routing strategies such as those of modern-day helicopters. For safety, a UAM aircraft will use air-to-ground communications to report flight plan, off-nominal events, and real-time movements to ground base stations (GBSs). A reliable communication network between GBSs and aircraft enables UAM to adequately utilize the airspace and create a fast, efficient, and safe transportation system. In this paper, to characterize the wireless connectivity performance in UAM, a stochastic geometry-based spatial model is developed. In particular, the distribution of GBSs is modeled as a Poisson point process (PPP), and the aircraft are distributed according to a combination of PPP, Poisson cluster process (PCP), and Poisson line process (PLP). For this setup, assuming that any given aircraft communicates with the closest GBS, the distribution of distance between an arbitrarily selected GBS and its associated aircraft and the Laplace transform of the interference experienced by the GBS are derived. Using these results, the signal-to-interference ra-tio (SIR)-based connectivity probability is determined to capture the connectivity performance of the aircraft-to-ground communication network in UAM. Simulation results validate the theoretical derivations for the UAM wireless connectivity and provide useful UAM design guidelines by showing the connectivity performance under different parameter settings.