Geometry-free TDRTK: a new time-difference RTK model considering multi-frequency observations

Abstract

The time difference RTK (TDRTK) of GNSS can obtain high-precision baseline constraints to control the cumulative error of dead reckoning technology. However, the availability of traditional TDRTK decreases sharply with the increase of time interval. A geometry-free TDRTK method with quality control using multi-frequency observations is proposed to solve this problem. Experimental shows that in the dynamic condition of a stand-alone GNSS receiver, the average and maximum relative position accuracy (10 min and 10 kilometres tests) of the proposed method are improved by 42.2% and 44.2% compared with the existing methods.

Keywords:

• Global Navigation Satellite System (GNSS)
• Factor graph optimization
• Baseline constraint
• Protection level
• Geometry-free time difference RTK

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by National Natural Science Foundation of China: [grant number 42074014].

Notes on contributors

Chunhe Liu

Chunhe Liu, a doctor of geography, dedicated to research on GNSS/INS/LiDAR integrated navigation. His recent research achievements include A time difference RTK model considering ephemeris errors (Beijing, 2022), etc.

Hongzhou Chai

Hongzhou Chai has been a professor since 2008 and a Ph.D. supervisor since 2011 at the Zhengzhou Institute of Surveying and Mapping, China, where he received his doctorate in 2006. His research interests include surveying data processing and GNSS positioning and navigation.

Minzhi Xiang

Minzhi Xiang is currently a Ph.D. candidate at the Zhengzhou Institute of Surveying and Mapping, China. He has obtained his B.Sc. in Engineering from the University of Central South in 2011. His research interests include multi-sensor fusion, robot navigation and control theory.

Zhenqiang Du

Zhenqiang Du is currently a Ph.D. candidate at Zhengzhou Institute of Surveying and Mapping, China, where he received his B.Sc. degree in 2018. His research interests include GNSS precise point positioning and its integration with inertial navigation system.