• 同济大学测绘学科创建90周年 •

### GBM快速轨道产品及非差模糊度固定对其精度的改进

1. 1. 德国地学中心大地测量, 德国 波茨坦 14473;
2. 中国科学院上海天文台, 上海 200030;
3. 柏林工业大学, 德国 柏林 10553
• 收稿日期:2021-09-11 修回日期:2022-03-24 发布日期:2022-04-24
• 通讯作者: 王君刚 E-mail:jgwang@gfz-potsdam.de
• 作者简介:邓志国(1978-),男,博士,研究员,研究方向为GNSS卫星定轨,GNSS高精度数据处理及GNSS大气。.E-mail:deng@gfz-potsdam.de
• 基金资助:
中德博士后交流项目（ZD202121）

### The GBM rapid product and the improvement from undifferenced ambiguity resolution

DENG Zhiguo1, WANG Jungang1,2, GE Maorong1,3

1. 1. GFZ German Research Centre for Geosciences, Geodesy, Potsdam 14473, Germany;
2. Shanghai Astronomical Observatory, Chinese Academy of Science, Shanghai 200030, China;
3. Technical University of Berlin, Berlin 10553, Germany
• Received:2021-09-11 Revised:2022-03-24 Published:2022-04-24
• Supported by:
Helmholtz-OCPC Post Program (ZD202121)

Abstract: Global navigation satellite systems (GNSS) plays a critical role for providing real-time position-ing and navigation services, and the precise satellite orbit and clock products are essential for the high-precision GNSS applications. The international GNSS service (IGS) and its analysis centers (ACs) have been working on the study on precise GNSS data processing and provision of the precise products. The German research center for geosciences (GFZ), as one of the ACs, also provides the multi-GNSS rapid product: the GBM product. We introduce the GBM data processing strategy, analyze the precision of GBM multi-GNSS orbits from 2015 to 2021, and present the impact of applying the undifferenced ambiguity resolution on satellite orbits. The GPS orbits of GBM products agree with the IGS final orbits at the level of 11~13 mm in the three directions, and the GPS orbit 6 hour prediction precision is around 6 cm. The 6 hour prediction precision of GLONASS is around 12 cm, slightly worse than that of Galileo, which holds an average value of 10 cm in the same period but shows a significant improvement to around 5 cm after the end of 2016. The prediction precision of BDS medium earth orbit (MEO) satellites are around 10 cm, and that of the BDS geostationary earth orbit, (GEO) satellites and QZSS satellites are at the level of 1 to 3 meter. The satellite laser ranging (SLR) residuals show that the orbit precision of Galileo, GLONASS, and BDS3-MEO are 23, 41, and 47 mm, respectively. Moreover, comparing the double-differenced ambiguity resolution, adopting the undifferenced ambiguity resolution improves the 6 hour orbit prediction precision by 9%~15%,15%~18%,11%~13%,6%~17% and 14%~25% for the GPS, GLONASS, Galileo, BDS-2 and BDS-3 MEO satellites, respectively.