1. School of Electronic and Information Engineering, Beijing Jiaotong University, Beijing, China
2. State Key Laboratory of Advanced Rail Autonomous Operation and School of Electronic and Information Engineering, Beijing Jiaotong University, Beijing, China
3. Department of Informatics and Telecommunications, National and Kapodistrian University of Athens, Athens, Greece
4. Graduate School of Science and Engineering, Hosei University, Tokyo, Japan
5. Mohamed Bin Zayed University of Artificial Intelligence, Abu Dhabi, United Arab Emirates