Dr. Ruijie Xi mainly engaged in the research of Beidou/GNSS high precision navigation and positioning, intelligent construction and monitoring based on Beidou/INS/Vision/LiDAR fusion technology, and indoor and outdoor integrated positioning applications. He has been selected for the "International Exchange Program for Postdoctoral Researchers" of the China Postdoctoral Science Foundation in 2019. In recent years, he has led over four national and provincial projects, including the National Natural Science Foundation of China, the China Postdoctoral Science Foundation, etc. He has also participated in more than 10 projects including the National Key Research and Development Program and the National Natural Science Foundation of China for Distinguished Young Scholars, etc. More than 30 papers have been published in top journals such as Journal of Geodesy, GPS Solutions, IEEE TRGS, etc., more than 10 national invention patents have been applied for, and 3 software copyrights have been authorized.