Performance of BDS triple-frequency positioning based on the modified TCAR method

Abstract

A modified TCAR method to improve the NL ambiguity resolution over medium-long baseline is presented. The estimated DD ionospheric delay derived from the Kalman-filter floating solution is adopted to modify the floating NL ambiguities. Modified by the smooth DD ionospheric delay, the NL ambiguity residuals are mostly within 0.5 cycles over medium-long baselines, showing a significant improvement in contrast to the classical TCAR method. The positioning performances of the modified method are even better than the LAMBDA method over 72 and 634 km baselines. As the ambiguity can be correctly fixed just after several epochs, high-precision positioning can be achieved in a very short time.

Keywords:

• real BDS data
• three-carrier ambiguity resolution (TCAR)
• NL ambiguity resolution
• positioning evaluation

Notes on contributors

Yijun Tian is a Ph.D. candidate at Zhengzhou Institute of Surveying and Mapping. His main research activities comprise high-precision GNSS positioning and precision attitude determination. Email address: [email protected].

Lifen Sui is a professor at Zhengzhou Institute of Surveying and Mapping. Her main research activities comprise high-precision GNSS positioning and attitude determination. Email address: [email protected].

Dongqing Zhao is an associate professor at Zhengzhou Institute of Surveying and Mapping. His main research activities are navigation and location-based services. Email address: [email protected].

Yuan Tian is a master student at Zhengzhou Institute of Surveying and Mapping. He obtained his B.Sc. degree in 2015. His research focuses on GNSS attitude determination. Email address: [email protected].

Xu Feng is a master student at Zhengzhou Institute of Surveying and Mapping. He obtained his B.Sc. degree in 2015. His research focuses on modelling method of ionosphere based on GNSS. Email address: [email protected].

Qu Mengya is a chart carto-graphers at China Navigation Publications Press in Tianjin. She obtained the MS degree in remote sensing in 2017. Email address: [email protected].

Additional information

Funding

This work is funded by the National Natural Science Funds of China [grant numbers 41674016, 41274016, and 41774037].