Abstract
An increasing number of satellites of global navigation satellite systems (GNSS) and their constant modernization allow improving positioning accuracy and enable performing the GNSS measurements in challenging environments. Since 2016, the Centre National d’Études Spatiales (CNES) has been providing real-time corrections for all GNSS and thus allows for the actual multi-GNSS precise point positioning in real time without any issues associated with the latency of orbit and clock products as in the case of the IGS final products. We provide a comprehensive evaluation of the availability and the quality of multi-GNSS real-time orbit and clock products through the comparison to the final Center for Orbit Determination in Europe (CODE) orbits, fitting long continuous orbital arcs, analyzing the orbit position differences with respect to satellite laser ranging observations, as well as the assessment of clock stability using modified Allan deviation diagrams. The 3D orbit RMS over a 1-month test period, when compared to CODE products, is 5, 10, 18, 18 and 36 cm for GPS, GLONASS, Galileo, BeiDou MEO and BeiDou IGSO, respectively. The error of BeiDou geostationary orbits is above the 1-m level. Finally, we found that the quality of orbits and clocks is a function of the satellite system, orbital plane and the elevation of the Sun above the orbital plane, the satellite altitude, as well as the satellite block and generation.
Highlights
Precise point positioning (PPP) is an undifferenced technique that employs a single global navigation satellite systems (GNSS) receiver (Zumberge et al 1997)
We evaluate the quality of RT orbits using three complementary methods: (1) comparison with the post-processing Multi-GNSS experiment (MGEX) products, (2) analysis of orbit discontinuities through fitting long and continuous arcs and (3) comparison through the independent satellite laser ranging (SLR) technique
We assessed the availability and the accuracy of RT multiGNSS products provided by Centre National d’Études Spatiales (CNES)
Summary
Precise point positioning (PPP) is an undifferenced technique that employs a single GNSS receiver (Zumberge et al 1997). PPP takes advantage of precise satellite clocks and orbits that are considered fixed parameters in the normal equation system. As PPP has been dynamically developed over the years (Choy et al 2017), it is necessary to use as accurate products as possible in order to avoid error propagation and to fully exploit the PPP potential. The user must fully rely on the quality of the orbits and clocks provided. The primary application of PPP is coordinate determination. Another application field is space weather monitoring (Lu et al 2015), the estimation of the zenith total delay to support numerical weather prediction models (Dousa and Vaclavovic 2014) or detecting earthquakes or tsunamis (Collins et al 2009, Li et al 2013)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
