1. State Key Laboratory of Internet of Things for Smart City, University of Macau, Macau, China; Department of Computer and Information Science, University of Macau, Macau, China
2. State Key Laboratory of Internet of Things for Smart City, University of Macau, Macau, China; Department of Computer and Information Science, University of Macau, Macau, China; Zhuhai-UM Science and Technology Research Institute, Zhuhai 519031, China
3. College of Electronics and Information Engineering, Shenzhen University, Shenzhen 518060, China
4. College of Information Engineering, Zhejiang University of Technology, Hangzhou 310014, China
5. Department of Communication Engineering, Dalian Maritime University, Dalian 116026, China