1. Institute of Space Sciences Shandong University Weihai China
2. State Key Laboratory of Geo‐information Engineering Xi'an China
3. Research Group of Astronomy and Geomatics (gAGE) Universitat Politecnica de Catalunya (UPC) Barcelona Spain
4. National‐Local Joint Engineering Laboratory of Geo‐Spatial Information Technology Hunan University of Science and Technology Xiangtan China