1. School of Computer & Communication Engineering, University of Science and Technology Beijing, Beijing 100083, China
2. Satellite Frequency and Orbit Resource Agency, State Radio Monitoring Center, Beijing 100041, China
3. School of Automation and Electrical Engineering, University of Science and Technology Beijing, Beijing 100083, China
4. School of Computer & Communication Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, Institute of Artificial Intelligence, University of Science and Technology Beijing, Beijing 100083, China