Radar-based altitude over ground estimation of UAVs

Abstract

A 26 GHz low-cost, low power, and low complexity pulse correlation radar (PCR) for online altitude over ground estimation of an unmanned aerial vehicle (UAV) is presented. In the experimental part of this paper, measurement results of the customized lightweight radar are shown. Therefore, this radar, a commercially available lidar sensor, and a real time kinematic global navigation satellite system (RTK GNSS) are mounted on a UAV. It is shown that in sparse vegetation, the radar in combination with a particle filter outperforms the lidar sensor. Besides, it is explained, why strong radar reflections can lead to a time offset of the particle filtered altitude. As an application, a radar-based terrain map is presented.