1. Department of Electrical Engineering and Information Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia, Department of Information Media Technology, School of Information and Telecommunication Engineering, Tokai University (Takanawa Campus), Tokyo, Japan
2. Department of Electrical Engineering and Information Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia
3. Department of Information Media Technology, School of Information and Telecommunication Engineering, Tokai University (Takanawa Campus), Tokyo, Japan