Measurement of Power Line Radiation over Eastern Asia and Northern Europe by the EXOS-A "OHZORA" Satellite

The global measurement of the magnetic field strength at the fundamental frequencies of 50 and 60 Hz and their harmonics of power line radiation in the topside ionosphere region has been observed by the instrument on board the satellite "OHZORA" over the global area. The observation has started on June 1, 1984 and continued until today. The receiving unit of this observation consists of three narrow bandwidth filters as 50, 55 and 60 Hz. The background noise strength at 50 and 60 Hz can be determined in comparizon with the strength at 55 Hz. In this paper, the satellite observation were obtained many reasonable and agreeable data of power line radiations over Japan Islands, Eastern Asia and over northern Europe included the Auroral Oval area.