1. School of Electronics and Telecommunications, Hanoi University of Science and Technology, 01 Dai Co Viet, Hanoi, Vietnam
2. Biomedical Engineering Department, Amirkabir University of Technology, Tehran 15875–4413, Iran
3. Physics Department, Aristotle University of Thessaloniki, Thessaloniki, GR–54124, Greece
4. Department of Electronic Engineering, City University of Hong Kong, Hong Kong SAR, P. R. China