1. College of Electrical and Information Engineering, Hunan University, Changsha, 410082 Hunan Province, China
2. Zhejiang Zheda Mingquan Technology Co., Ltd., Hangzhou, 310030 Zhejiang Province, China
3. Hunan Institute of Metrology and Testing, Changsha, 410205 Hunan Province, China
4. Gdansk University of Technology, ul. G. Narutowicza 11/12, 80-233 Gdańsk, Poland