Dual-frequency receiving antennas for the Nobeyama radioheliograph using frequency selective subreflectors

It is quite important in radio astronomy to observe at several frequency bands for investigation on characteristics of radio emission. Especially in observing solar radio flares, which suddenly occur and rapidly change in intensity and structure, simultaneous observations are necessary at multiple frequencies to determine spectra of the sources. In order to observe solar flares at short centimeter wavelengths, the authors have developed a dual-frequency receiving antennas for the Nobeyama radioheliograph using frequency selective subreflectors