1. China Academy of Information and Telecommunications Technology (CAICT), Beijing, China
2. Key Laboratory of Universal Wireless Communications, Ministry of Education, Beijing University of Posts and Telecommunications, Beijing, China
3. Global Big Data Technologies Centre, University of Technology Sydney, Sydney, NSW, Australia
4. University of Technology Sydney, Ultimo, NSW, Australia
5. State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing, China
6. Artificial Intelligence Research Center, National Innovation Institute of Defense Technology, Beijing, China