Fast location survey of DGNSS reference station to support UAV navigation

Mobile Differential Global Navigation Satellite Systems (Mobile DGNSS) formed with multiple UAVs can support missions on a battlefield by providing navigation with high accuracy and integrity. For time efficiency and maneuverability of the system, the reference stations that are deployed and sited on the battlefield should be able to determine their precise position rapidly before generating the differential corrections. This paper presents a methodology for fast location surveying of the reference stations, which improves the GNSS-based position estimates of reference stations using precise measurements of relative distances between the stations. Simulation results showed that the proposed method enables users to achieve the desired accuracy in less time than the simple method which averages stand-alone GNSS solutions only. A theoretical model of DGNSS position uncertainty induced by inaccurate surveyed locations of the reference stations was also defined in this paper. The model was validated by comparing it to the results from experiments conducted with a DGNSS test-bed equipped with three GNSS receivers and a pseudo-user.