Impact of Galileo Observations on the Position and Ambiguities Estimation of GNSS Reference Stations

Development of Galileo navigation system has caused that it is increasingly used in various areas. One of the most important of them is precise positioning of the reference networks. In this paper we present the impact of Galileo observations on the differential precise positioning as well as ambiguities resolution of selected GNSS stations. We tested five different solutions: GPS-only, Galileo-only, GPS/Galileo, GPS/GLONASS and GPS/GLONASS/Galileo. Calculations were performed using Bernese 5.2 software. Results indicate that the best positioning results are possible when the GPS and Galileo observations are used together, excluding GLONASS. We obtained standard deviation below 2 mm for North and East coordinates and below 6 mm in Up direction. Moreover, when GPS/Galileo observation were performed, we reached widelane and narrowlane mean ambiguities resolution more than 90 % and 85 % for Galileo and 80 % and 75 % for GPS. Furthermore, we discussed impact of the IGS14 antenna calibrations on Galileo positioning results.