1. Division of Electronic Communication, Korea Rail Network Authority, 242 Jungang-ro, Dong-gu, Daejeon, 34618, Korea
2. Industrial-Academic Convergence Research, 1362 Wolpyeong-dong, Seo-gu, Daejeon, 35226, Korea
3. Department of Information and Communication Engineering, Hanbat National University, 125 Dongseo-daero, Yuseong-gu, Daejeon, 34158, Korea