Radio Channel Modeling for UAV Communication Over Cellular Networks

The main goal of this letter is to obtain models for path loss exponents and shadowing for the radio channel between airborne unmanned aerial vehicles (UAVs) and cellular networks. In this pursuit, field measurements were conducted in live LTE networks at the 800 MHz frequency band, using a commercial UAV. Our results show that path loss exponent decreases as the UAV moves up, approximating freespace propagation for horizontal ranges up to tens of kilometers at UAV heights around 100 m. Our findings support the need of height-dependent parameters for describing the propagation channel for UAVs at different heights.