1. Department of Electronics Engineering, Daegu Catholic University, Hayang, Kyeongsan, Kyeongbuk 38430, South Korea
2. Department of Electrical and Computer Engineering, University of Seoul, 90 Jeonnong, Tongdaimoon-Gu, Seoul 02504, South Korea
3. WOORIRO Co., Ltd., 102-22 Pyeongdongsandan 6beon-ro, Gwangsan-gu, Gwangju 62453, South Korea