A Global Navigation Augmentation System Based on LEO Communication Constellation

In the background of booming development of low earth orbit (LEO) communication systems, a global navigation augmentation system based on LEO communication constellation is proposed in this paper. The LEO satellites can serve both as space-based monitoring stations and as navigation information broadcasting sources. The system can be developed together with the LEO communication system, and do not need to build a new system. The Hongyan LEO communication system under construction by China Aerospace and Technology Corporation (CASC) is adopted for the analysis in the paper. When served as space-based monitoring stations, the LEO satellites can jointly determine the precise orbits and clock errors of GNSS satellites and LEO satellites with the data from the mounted high precision GNSS monitoring receiver and the ground based monitoring stations. When served as navigation information broadcasting sources, the Assistant GNSS (AGNSS) architecture is used to broadcast assistant navigation information, and the general-purpose GNSS receiver can realize fast signal acquisition in the extremely complicate environment and achieve better antijamming capability for the navigation availability augmentation. For the navigation precision augmentation, besides the precise orbit, precise clock error, and integrity augmentation information, an additional navigation augmentation signal is broadcasted to realize global precise point positioning (GPPP) with sub-meter positioning precision level in dynamic mode and sub-decimeter precision level in static mode. The convergence time of precise point positioning is shorten from 30 minutes using a GNSS system alone to less than 5 minutes using a GNSS system together with the LEO global navigation augmentation system.