1. College of Geomatics, Xi’an University of Science and Technology, Xi’an, China
2. State Key Laboratory of Geodesy and Earth’s Dynamics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, China
3. School of Geodesy and Geomatics, Wuhan University, Wuhan, China
4. Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, Wuhan University, Wuhan, China