The implementation of multi-GNSS real-time precise point positioning service system: GPS/GLONASS

With the development of precise point positioning (PPP) techniques, the real-time PPP service is also progressing. The realization of this real-time system can develop the market of PPP and it can also do some real-time researches, such as earthquake, etc. In addition, multi-GNSS can increase the number of satellites and also good constellation geometries. Therefore, it is beneficial to the positioning performance in terms of availability and reliability. This paper mainly introduces the structure of multi-GNSS real-time precise point positioning service system and the measures about how to build the platform. And it also discusses the differences between real-time PPP and post-processing PPP, and the differences between single-system and dual-system PPP. Certainly, it also briefly introduces the theories and methods of real-time satellite clock error and PPP computations. The experiments are carried out and the positioning achievement is analyzed. Based on the experimental results, the positioning precision and the convergence efficiency of dual-system are better than the GPS-only system. All 3D components of positions can reach centimeter-level accuracy.