Contribution of Using Multiple GNSS Constellations in Precise Point Positioning Applied to Monitoring

Abstract

With the evolution of GNSS constellations and positioning algorithms, Precise Point Positioning (PPP) has established itself as a viable alternative for the geodetic monitoring of structures in urban environments. This study investigates the performance of the PPP method using different combinations of GNSS constellations – GPS, GLONASS, Galileo, and BeiDou – in a controlled setting, with simulated horizontal displacements and statistical analysis of the results. The methodology involved GNSS data collection at points with predefined displacements, followed by processing with RTKLIB software and application of the Student’s t-test to assess significant differences. The results showed that although the use of MULTI-GNSS increased the robustness of the solutions, the GPS + Galileo combination delivered statistically comparable performance, especially under more stable tracking conditions. However, it was found that both configurations still present limitations in the precise detection of millimetric displacements when less rigid supports were used. The altitude data also showed significant variability, indicating the need for refinement in vertical correction models. This demonstrates that PPP using multiple constellations or GPS + Galileo can be effective for urban monitoring, provided that the operational and structural constraints of the application environment are respected.