# Theoretical Investigations and Practical Studies Using High Rate Satellite Orbit & Clocks Estimation by Bernese Software for Realtime PPP Applications

### Status: Abgeschlossen, August 2016

Bearbeitung: M.Sc. Nicolas Garcia Fernandez

The OPPP techniques used in the navigation field require the use of precise orbit files in SP3 format in order to perform the coordinate computation. As a result, the Internet connection becomes a restriction, since the software is downloading real-time precise orbit data to compute the coordinates. The accuracy of the computation depends on the positioning mode (PPP-Static or PPP-Kinematic) and in the IGS SP3 product used for the computation. In this thesis, the influence of the SP3 interval (precise orbit recomputation) has been evaluated.

As a second step, in order to avoid the necessity of being permanently online, the orbit prediction (Clock parameters and ERP parameters) becomes another matter to analyze in this thesis (PPP). Therefore, it was also necessary to evaluate the accuracy of the different predicted orbits in order to find the best configuration for every navigation situation.

To perform the orbit & clock parameter estimation, Bernese GNSS Software v.5.2 was used.

### Orbit & Clock parameter comparison

Comparing the results obtained with a reference (Final product used as “true” position of the satellites) is very important in order to know which orbit to use in each situation (e.g. the predicted orbit coordinates differ an average of

around 7 cm while Real-time orbits only differ an average of 1,8 cm, and regarding Clock parameters, the predicted orbits differ from the Final orbits around 10µm while Real-time around 15µm).

Figure: Differences of obtained Orbit coordinates with respect to Final