摘要
GNSS是实时定位导航最重要的方法,精密卫星轨道钟差产品是GNSS高精度服务的前提。国际GNSS服务中心(IGS)及其分析中心长期致力于GNSS数据处理的研究及高精度轨道和钟差产品的提供。GFZ作为分析中心之一,提供GBM多系统快速产品。本文基于2015—2021年GBM提供的精密轨道产品,阐述了数据处理策略,分析了轨道的精度,介绍了非差模糊度固定的原理和对精密定轨的影响。结果表明:GBM快速产品中的GPS轨道精度与IGS后处理精密轨道相比的精度约为11~13 mm,轨道6 h预报精度约为6 cm;GLONASS预报精度约为12 cm,Galileo在该时期的精度均值为10 cm,但是在2016年底以后精度提升到5 cm左右;北斗系统的中轨卫星(medium earth orbit,MEO)在2020年以后预报精度约为10 cm;北斗的静止轨道卫星(geostationary earth orbit,GEO)卫星和QZSS卫星的预报精度在米级;卫星激光测距检核表明,Galileo、GLONASS、BDS-3 MEO卫星轨道精度分别为23、41、47 mm;此外,采用150 d观测值的试验结果表明,采用非差模糊度固定能显著改善MEO卫星轨道精度,对GPS、GLONASS、Galileo、BDS-2和BDS-3的MEO卫星的6 h时预报精度改善率分别为9%~15%、15%~18%、11%~13%、6%~17%和14%~25%。
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.
作者
邓志国
王君刚
葛茂荣
DENG Zhiguo;WANG Jungang;GE Maorong(GFZ German Research Centre for Geosciences, Geodesy, Potsdam 14473, Germany;Shanghai Astronomical Observatory, Chinese Academy of Science, Shanghai 200030, China;Technical University of Berlin, Berlin 10553, Germany)
出处
《测绘学报》
EI
CSCD
北大核心
2022年第4期544-555,共12页
Acta Geodaetica et Cartographica Sinica
基金
中德博士后交流项目(ZD202121)。
关键词
GNSS
精密定轨
模糊度固定
GNSS
precise orbit determination
ambiguity fixing
