1. Hubei Province Engineering Technology Research Center for Construction Quality Testing Equipments and College of Computer and the Information Technology, China Three Gorges University, Yichang, China
2. College of Telecommunications and Information Engineering, Nanjing University of Posts and Telecommunications, Nanjing, China
3. Department of Engineering, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, U.K
4. Research Organization of Electrical Communication, Tohoku University, Sendai, Japan