Investigations into the quality of final-product dual-frequency kinematic PPP in open sky using CSRS-PPP free online service: GPS Vs. GPS + GLONASS

The Global Positioning System (GPS) provides accurate, continuous, and global positioning and timing information through satellite-based observations. However, single-system configurations are limited by satellite geometry and signal availability, which can affect positioning reliability in dynamic environments. This study evaluates the performance of Kinematic Precise Point Positioning (PPP) using the Canadian Spatial Reference System Precise Point Positioning (CSRS-PPP) service under two configurations: GPS-only and GPS combined with GLONASS in open sky where the effect of multipath is non-existent. Dual-frequency observations were collected on 10 well-distributed fixed points for 24 hours each and processed in both static and kinematic modes. The static PPP results were used as the reference to assess the accuracy of kinematic solutions. The results show that integrating GLONASS with GPS improves in average the consistency and reliability of GPS alone kinematic PPP solutions by nearly 13% in Easting, 15% in Northing, and 21% in Height. Also, the integrated solutions help to reduce the percentage of gross errors in GPS alone kinematic PPP solutions and enhancing positional precision by nearly 15% in Easting, 21% in Northing, and 18% in Height. Although the improvement in overall average accuracy is marginal, the overall stability of the solution demonstrates the advantage of multi-constellation PPP processing.