title: Modeling and Assessment of GPS/BDS Combined Precise Point Positioning.
abstract: Precise Point Positioning (PPP) technique enables stand-alone receivers to obtain cm-level positioning accuracy. Observations from multi-GNSS systems can augment users with improved positioning accuracy, reliability and availability. In this paper, we present and evaluate the GPS/BDS combined PPP models, including the traditional model and a simplified model, where the inter-system bias (ISB) is treated in different way. To evaluate the performance of combined GPS/BDS PPP, kinematic and static PPP positions are compared to the IGS daily estimates, where 1 month GPS/BDS data of 11 IGS Multi-GNSS Experiment (MGEX) stations are used. The results indicate apparent improvement of GPS/BDS combined PPP solutions in both static and kinematic cases, where much smaller standard deviations are presented in the magnitude distribution of coordinates RMS statistics. Comparisons between the traditional and simplified combined PPP models show no difference in coordinate estimations, and the inter system biases between the GPS/BDS system are assimilated into receiver clock, ambiguities and pseudo-range residuals accordingly.
authors.affiliation: Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China. junping@shao.ac.cn.|Shanghai Key Laboratory of Space Navigation and Positioning Techniques, Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China. junping@shao.ac.cn.
authors.forename: Junping
authors.initials: J
authors.lastname: Chen
authors.affiliation: Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China. 1335465@tongji.edu.cn.|College of Surveying and Geo-informatics Engineering, Tongji University, Shanghai 200092, China. 1335465@tongji.edu.cn.
authors.forename: Jungang
authors.initials: J
authors.lastname: Wang
authors.affiliation: Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China. 1130797@tongji.edu.cn.|College of Surveying and Geo-informatics Engineering, Tongji University, Shanghai 200092, China. 1130797@tongji.edu.cn.
authors.forename: Yize
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China. snyang@shao.ac.cn.
authors.forename: Sainan
authors.initials: S
authors.lastname: Yang
authors.affiliation: Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China. qianchen@shao.ac.cn.
authors.forename: Qian
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China. xqgong@shao.ac.cn.
authors.forename: Xiuqiang
authors.initials: X
authors.lastname: Gong
keywords: BDS; ISB; MGEX; multi-GNSS; precise point positioning