1. Nantong Ocean and Coastal Engineering Research Institute, Hohai University, Nantong 226000, China
2. Changzhou Key Laboratory of Photovoltaic System Integration and Production Equipment Technology, Changzhou 213022, China
3. Department of Information and Communication Systems, Hohai University, Changzhou 213022, China
4. School of Computer & Communication Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
5. Instituto de Telecomunicações, University of Beira Interior, 6201-001 Covilhã, Portugal