Chih-Yang Hsu, Wen-Tsan Hsieh, Chien-Nan Jimmy Liu and Jing-Yang Jou
Department of Electronics Engineering
National Chiao Tung University
Hsinchu, 300 Taiwan
E-mail: {hsucy; jyjou}@eda.ee.nctu.edu.tw
+Department of Electrical Engineering
National Central University
Taoyuan, 320 Taiwan
E-mail: {wthsieh; jimmy}@ee.ncu.edu.tw