1. School of Information and Communications Engineering, Xi’an Jiaotong University, Xi’an, China
2. Guangzhou Institute of Technology, Xidian University, Guangzhou, China
3. Department of Electrical and Computer Engineering, University of Windsor, Windsor, Canada
4. Department of Sciences and Informatics, Muroran Institute of Technology, Muroran, Japan
5. Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, Canada
6. Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, USA