1. School of Electrical and Electronics Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
2. Key Laboratory of Optical Fiber Sensing and Communications, University of Electronic Science and Technology of China, 611731, Chengdu, Sichuan, China
3. Department of Mechanical Engineering, and Advanced Institute of Manufacturing with High-Tech Innovations, National Chung Cheng University, Chiayi 62102, Taiwan
4. Department of Electrical Engineering, National Cheng Kung University, Tainan City, 70101, Taiwan