UAV Air-Ground Channel Ray Tracing Simulation Validation

This paper provides a brief overview of air-ground (AG) channel models for low altitude Unmanned Aerial Vehicles (UAV) and a useful comparison between the results offered by ray-tracing (RT) simulations and measurements for an open environment surrounded by suburban clutter. The results show that there is a strong dependence of root-mean-square delay spread on the height of flight, and delay dispersion parameters remain constant above a certain height above the building average. Agreement between measurements and simulations is generally good, but less so at low heights. This implies that the propagation mechanisms at low heights are more complicated, and therefore, more efforts on precise modeling of the three-dimensional (3D) environment and propagation mechanism should be made in order to provide realistic UAV AG channels.