• 大地测量学与导航 •

### 北斗三频数据的两个无电离层组合轨道钟差估计及其应用

1. 1. 宇航动力学国家重点实验室, 陕西 西安 710043;
2. 西安卫星测控中心, 陕西 西安 710043
• 收稿日期:2019-07-24 修回日期:2020-06-22 发布日期:2020-11-25
• 作者简介:李杰(1984-),男,博士,助理研究员,研究方向为高精度GNSS数据处理。E-mail:992092681@qq.com
• 基金资助:
国家自然科学基金（11503096）

### Orbit determination and clock estimation via two ionosphere-free combinations of observation from BDS triple-frequency data and its application

LI Jie1,2, ZHANG Rongzhi1,2, ZENG Guang1,2, GONG Bing2, WANG Chong1,2, FANG Yanan1,2, ZHU Jun1,2, LI Junfeng1,2, QIANG Wen1,2

1. 1. State Key Lab of Astrodynamics, Xi'an 710043, China;
2. Xi'an Satellite Control Centre, Xi'an 710043, China
• Received:2019-07-24 Revised:2020-06-22 Published:2020-11-25
• Supported by:
The National Natural Science Foundation of China (No. 11503096)

Abstract: The international GNSS monitoring and assessment system (iGMAS) and the multi-GNSS experiments (MGEX) receive BeiDou navigation signals on different frequencies. In this paper, orbit determination and clock estimation based on two ionosphere-free combinations of observation (B1/B3 and B1/B2) from BDS triple-frequency data is proposed. In this method, data of both networks from BeiDou 2nd generation (BDS-2), BeiDou 3rd generation test system (BDS-3e) and BeiDou 3rd generation global system (BDS-3g) can be processed uniformly in one program run, which can effectively improve data usage at one run, thereby improving parameter estimation accuracy. The GPS and BDS data of iGMAS and MGEX were collected for several days for testing. The results show that for the BDS-3e+BDS-2+GPS joint orbit determination, the orbit overlap RMS of the BDS MEO is 9.5 cm after using the triple-frequency two-combination method, which is 29% higher than the accuracy of traditional dual-frequency processing. The new method introduces a code bias parameter related to three frequencies of each involving BDS-2 satellite. The result shows values of the parameter are quite stable for continuous one-day solutions, which proves that the model is reliable. The new method is used for BDS-3g+BDS-3e+BDS-2+GPS joint orbit determination. The 6 BDS-3g MEO satellite orbit overlap RMS is 14.5 cm, and the clock error overlap RMS is 0.43 ns, which is equivalent to 15.1 cm and 0.49 ns of BDS-3e. The BDS precise point positioning (PPP) test was carried out. The results show that after adding the precise orbit and clock difference of the six MEOs of BDS-3g, the horizontal positioning accuracy of the station is 39.6 mm, and the zenith accuracy is 37.8 mm, which increases positioning accuracy by 11.1% than BDS-2 and BDS-3e satellites only.