New progress of PPP/PPP-RTK and positioning performance comparison of BDS/GNSS PPP
张小红, 胡家欢, 任晓东
Abstract
This paper begins with a brief review of the current state of development of precise point positioning (PPP) in recent years, with a focus on summarizing the latest research progress of several hotspots such as real-time rapid estimation of high-rate satellite clocks, multi-GNSS PPP ambiguity resolution, multi-frequency GNSS PPP models and ambiguity resolution, rapid initialization of PPP and PPP-RTK. Then, the evaluation of positioning performance of single/multi-GNSS PPP with latest observation of GPS, GLONASS, Galileo and BDS, especially the positioning accuracy, convergence time and time to first fix of BDS-2+3, is given. The results show that:PPP performance of BeiDou Navigation Satellite System is comparable with other GNSS. The convergence time and time to first fix of BDS-2 and BDS-3 combined PPP are about 20~30 minutes, positioning accuracy of static PPP in east, north and up directions is at millimeter to centimeter level, while that of kinematic PPP reach 5 cm in horizontal and 7 cm in elevation direction. Multi-GNSS combination can improve positioning accuracy and shorten the convergence time and time to first fix significantly, the positioning accuracy of ambiguity-fixed solutions can be improved by 14.8, 12.0 and 12.8% in the east, north and up directions compared to float solutions, respectively. The convergence time and time to first fix of multi-GNSS PPP can be reduced by 36.5 and 40.4% compared to that of GPS PPP.