1. Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China
2. School of Microelectronics, Southern University of Science and Technology, Shenzhen 518055, China
3. Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
4. Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong, China
5. Engineering Research Center of Integrated Circuits for Next-Generation Communications, Ministry of Education, Southern University of Science and Technology, Shenzhen 518055, China
6. Department of Electrical and Electronic Engineering, Joint Appointment with School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China