Polish active geodetic network as a multi-functional nationwide navigation and positioning system

The aim. The aim of the work is the research of the possibilities of using the real time in geodetic satellite measurements, the support system of Ground-Based Augmentation System (GBAS) type [Prasad and Ruggieri 2005, Rife and Phelts 2009, Dawidowicz and Krzan 2014]. The paper analyzes the results and evaluates the actual accuracy of the real field measurements, depending on the selected solution. Applied solutions included using real-time in the measurements, two types of corrections, for the network and of a single reference station, and one or two positioning systems integrated with each other. The method. The research measurements were performed using the multifunction precise satellite positioning ASG-EUPOS system operating in Poland since 2008. This system is based on a network of ground reference stations GNSS, which are distributed approximately evenly throughout the country. The testing area consisted of points, which have previously been measured by the static method, and their coordinates have been determined in postprocessing. In the test measurements, four different services that provide differential corrections via the Internet were used. In the final result 3D coordinates of the test area points were obtained, and were subject to detailed analysis, in terms of obtained accuracy and precision of the coordinates determination, on the basis of a single measurement using selected services. Results. The results of measurements and performed analyzes of real-time measurements firstly showed advantages of network corrections over corrections from a single reference station. And secondly they helped to demonstrate empirically the advantage of measurements made on the basis of the two positioning systems with respect to the measurement using only one system. The new aspect of this work is the simultaneous use of the real-time measurements corrections for GPS and GLONASS satellites. Practical significance. The current state of advancement of the technology of satellite measurements performed in real time, allows the determination of coordinates with different accuracy, from the centimeter level accuracy to the decimeter accuracy. The type of measuring equipment used in this case plays an important role. On the basis of the performed experiment it is recommended to use two system receivers to ensure high measurements accuracy and certainty of the results.