Numerical investigation of an UWB localization technique for unmanned aerial vehicles in outdoor scenarios

In this paper, the numerical investigation of an ultra wideband (UWB) localization technique suitable for the tracking and control of an unmanned aerial vehicle (UAV) in a specific outdoor scenario is presented. A set of UWB nodes are located on a moving/still ground station (GS) and interrogate an UWB node placed on the UAV that is flying in front of the GS. The distances between the GS-nodes and the UAV-node are estimated through a conventional two-way time-of-flight ranging method, one at a time, and then used in a multilateration algorithm. Due to the unavoidable relative motion between the UAV and the GS, the above distances are actually measured for different UAV-GS relative positions, and then, the UAV localization performance deteriorates as a function of the UAV-GS relative speed and the ranging-method processing time. An approach is here proposed to mitigate the above adverse effect, by exploiting an estimate of the UAV-GS relative speed along the GS forward direction. A preliminary numerical analysis is used to show that a decimeter order localization accuracy can be obtained for a tridimensional localization process.