Capabilities of a Real-Time EKF Vector Tracking Algorithm for Dynamic Flight Maneuvers With Small UAVs

Abstract

To strengthen tracking in dynamic flight maneuvers the miniaturized real-time Global Navigation Satellite System (GNSS) receiver GALileo ANTenna (GALANT), developed by the German Aerospace Center (DLR), has been equipped with a robust vector tracking algorithm. To harden the receiver the algorithm used on the platform excludes Non-Line-Of-Sight signals by exploiting spatial information gained by the 2×2 antenna array and its processing. This contribution focuses on the planning, execution and evaluation of the experimental validation of the receiver and its tracking algorithm by conduction of open field flight test in the rural area near Munich. The developed system was fitted as payload to a compact hexacopter and the potential benefits in signal tracking are investigated, while the algorithm relies on GNSS information only and uses no other sensor data input such as Inertial Measurement Unit (IMU) or compass. The receiver has been developed to be resilient to intentional and unintentional interference from diverse origins based on spatial suppression of jamming sources, which has been proven in previous tests. Performing these techniques also suppresses satellite signals impinging from the direction of the interference source, which need to be recovered. To test the performance of the implemented vector tracking algorithm with respect to the signal recovery, the receiver is exposed to a jamming source on ground while changing the constellation.