Funding for this research was provided by:
National Key Research and Development Program (2016YFA0600302)
the National Natural Science Foundation of China (41201357)
Technology Cooperation Project of Sanya (2015YD18)
Key Laboratory of Satellite Mapping Technology and Application, National Administration of Surveying (KLMSTA-201605)
Article History
Received: 19 July 2018
Accepted: 15 November 2018
First Online: 7 December 2018