Multi-constellation GNSS precise point positioning using GPS, GLONASS and BeiDou in Australia

GNSS Precise Point Positioning (PPP) is a promising approach to high accuracy (centimetre to decimetre-level) positioning with a single receiver ,which does not need a nearby reference station like traditional precise positioning technique such as differential positioning. The advent of multi-constellation satellite systems, such as China's BeiDou and European Union's Galileo, offers additional satellites and observables, which can strengthen the positioning model thereby improving the accuracy and convergence time of PPP. This paper describes the prospects and challenges in combining multiple GNSS systems such as GPS+GLONASS+BeiDou in a PPP model. In particular, it aims to assess the performance of the combined system in terms of positional accuracy, reliability and time of convergence in static and kinematic PPP modes. The result indicates that the combined GPS+GLONASS+BeiDou kinematic PPP solution significantly improve the positioning accuracy by approximately 20% and 30% in the horizontal and vertical components, respectively; and also shorten the convergence time by more than 20% compared to GPS-only kinematic PPP solution. However, for the static PPP solution, the positioning accuracy and convergence time of the combined system is marginally improved compared to the GPS-only static PPP solution.