1. School of Computer Science and Educational Software, Guangzhou University, Guangzhou, China
2. School of Physics and Electronic Engineering, Guangzhou University, Guangzhou, China
3. Guangdong University of Technology, Guangdong, China
4. Key Laboratory of Cognitive Radio and Information Processing, Guilin University of Electronic Technology, Guilin, China
5. State Key Laboratory on ISN, School of Telecommunications Engineering, Xidian University, Xi’an 710071, China
6. School of Information and Communication Engineering, Dalian University of Technology, Dalian, China
7. School of Information Engineering, East China Jiaotong University, Nanchang, China