1. Department of Engineering, The University of Sydney, Sydney, NSW, Australia
2. R&D Center, Guangxi Huanan Communication Company Ltd., Nanning, China
3. School of Electronic and Information Engineering, South China University of Technology, Guangzhou, China
4. Instituto de Telecomunicações, Aveiro, Portugal
5. Department of Computer Science and Engineering, SCMS School of Engineering and Technology, Ernakulam, India