Uplink Performance Analysis of a Drone Cell in a Random Field of Ground Interferers

Aerial base stations are a promising technology to increase the capabilities of the existing communication networks. However, the existing analytical frameworks do not sufficiently characterize the impact of ground interferers on the aerial base stations. In order to address this issue, we model the effect of interference coming from the coexisting ground networks on the aerial link, which could be the uplink of an aerial cell served by a drone base station. By considering a Poisson field of ground interferers, we characterize the aggregate interference experienced by the drone. This result includes the effect of the drone antenna pattern, the height-dependent shadowing, and various types of environment. We show that the benefits that a drone obtains from a better line-of-sight (LoS) at high altitudes is counteracted by a high vulnerability to the interference coming from the ground. However, by deriving the link coverage probability and transmission rate we show that a drone base station is still a promising technology if the overall system is properly dimensioned according to the given density and transmission power of the interferers. Particularly, our results illustrate how the benefits of such network is maximized by defining the optimal drone altitude and signalto-interference (SIR) requirement.