1. a Department of Electrical Engineering, Institute of Microelectronics, National Cheng-Kung University, No. 1, University Road, Tainan City 701, Taiwan, R.O.C.
2. b Department of Electrical Engineering, Institute of Microelectronics, National Cheng-Kung University, No. 1, University Road, Tainan City 701, Taiwan, R.O.C.
3. c Institute of Computer and Communication Engineering, National Taipei University of Technology, 1, Sec. 3, Chung-Hsiao E. Road, Taipei 10608, Taiwan, R.O.C.
4. d Department of Electronic Engineering, I-Shou University, No. 1, Sec. 1, Syuecheng Road., Dashu, Kaohsiung 840, Taiwan, R.O.C.
5. e Department of Electrical Engineering, Institute of Microelectronics, National Cheng-Kung University, No. 1, University Road, Tainan City 701, Taiwan, R.O.C.;, Email: mphoung@eembox.ncku.edu.tw