Abstract:This paper analyzes the precise point positioning method of GPS, GLONASS and BDS three-system combination, including function model, estimation methods for tropospheric delay and differential code bias (DCB) parameters. The precise point positioning program based on three-system combination is developed using C++ language, and the measurements of 12 consecutive tracking stations of MEGX network are analyzed. The results show that the convergence rate and positioning accuracy of the ionospheric combination model and the non-combined model are similar and the convergence rate at the same station on different days is not significantly different. However, the non-combined model uses a priori ionospheric constraints can improve the convergence rate. Multi-system combination can reduce the PDOP value, thus improving the convergence rate and positioning accuracy. By using three-system precise point positioning, the horizontal accuracy is about 3 cm, elevation accuracy is about 5 cm. These results are better than those of three systems alone positioning or two systems combined positioning. When the cut-off elevation angle is large, the multi-system precise point positioning has higher stability than the single system.
MIAO Weikai,CHEN Xusheng,LIU Yangyang. Processing Method and Result Analysis of GNSS Multi-System Combined Precise Point Positioning[J]. jgg, 2019, 39(5): 521-527.