GNSS real-time precise point positioning with BDS-3 global short message communication devices

Abstract

Global short-message communication (GSMC) service is a new function of BeiDou-3 global navigation satellite system (BDS-3). Broadcasting precise orbit and clock corrections via GSMC provides an opportunity for real-time precise point positioning (PPP), especially in the areas where internet-based communication is not available, such as deserts and oceans. This research achieves a real-time multi-GNSS PPP based on the precise orbit and clock corrections broadcast via BDS-3 GSMC. To reduce the data size, the precise corrections of only visible GNSS satellites are broadcast, and three messages are used to broadcast the corrections of GPS, Galileo and BDS satellites. The encoding strategy of corrections is designed and a procedure for real-time PPP with BDS-3 GSMC is described. To evaluate the positioning performance of the proposed real-time PPP scheme, the simulated kinematic real-time PPP experiments with BDS-3 GSMC corrections and Centre National d’Etudes Spatiales (CNES) real-time precise orbit and clock products are carried out by using observations of 7 days from 12 globally distributed IGS stations. The positioning accuracy in E, N and U components reach up to 3.3, 3.8 and 5.9 cm with GSMC corrections, which is comparable to that with CNES real-time products. Furthermore, a vehicle real-time PPP experiment is conducted using the devices with the function of BDS-3 GSMC and the positioning accuracy reach up to 4.1, 2.2 and 7.1 cm in E, N and U components after convergence.