1. College of Civil Aviation, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China
2. National Key Laboratory of Air Traffic Control Flight Flow Management Technology, Nanjing 211106, China
3. The 28th Research Institute of China Electronics Technology Group Corporation, Nanjing 210007, China
4. National Key Laboratory of Air Traffic Management Technology, Nanjing 210007, China