Sergii Panasenko¹、*Yuichi Otsuka²、Max van de Kamp³、Takuya Tsugawa⁴、Michi Nishioka⁴ (1.Institute of Ionosphere, Kharkiv, Ukraine、2.Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan、3.Finnish Meteorological Institute, Helsinki, Finland、4.National Institute of Information and Communications Technology, Tokyo, Japan)