抄録
A phased-array antenna with mini-TWTs to realize a 21-GHz-band-broadcasting satellite system with a function efficiently compensating for rain attenuation is introduced in this article. Rain attenuation of RF signals in the 21-GHz-band is 3 times larger (in dB unit) than that in the 12-GHz-band, in which the current satellite broadcasting is served. Rain attenuation compensation technique is indispensable to keep sufficient service availability in the 21-GHz-band-broadcasting satellite system. However because it is known that heavy rain usually falls only in limited areas, it will be effective to boost beam strength only for such rainfall areas by application of the phased-array antenna.
