Summary
International Symposium on Antennas and Propagation
2012
Session Number:3B1
Session:
Number:3B1-1
12/21GHz Dual-band Feed Antenna for Satellite Broadcasting Receiving Reflector Antenna
Masafumi Nagasaka, Susumu Nakazawa, Shoji Tanaka,
pp.-
Publication Date:2012/10/29
Online ISSN:2188-5079
Summary:
The International Telecommunication Union (ITU) has allocated 21.4 to 22.0GHz (21-GHz band) to the broadcasting satellite service (BSS) for Regions 1 and 3. Because of its wide bandwidth, satellite broadcasting in this band is expected to transmit large-capacity signals such as those for ultra high definition TV. We assume a 21-GHz-band broadcasting satellite whose orbital position is 110 degrees east, which is the same position as that of the satellite for the 12-GHz-band BSS currently used in Japan. We have been developing the 12/21-GHz dual-band parabolic reflector antenna that enables reception of broadcast services provided over these two different frequency bands with a single reflector antenna. This paper describes the configuration and the characteristics of the designed 12/21-GHz dual-band feed antenna. To achieve high gain in both bands, the edge illumination level (EIL) of the feed antenna in the 21-GHz band must be the same power level to that in the 12-GHz band. We evaluated the designed feed antenna with a particular focus on the voltage standing wave ratio (VSWR) and the EIL. The VSWR was less than or equal to 1.5 throughout the target range in both bands, and the EIL of the 21-GHz band was almost the same power level to that in the 12-GHz band. As a result of computing the radiation pattern for the parabolic reflector antenna fed by the designed feed antenna, the aperture efficiencies were 68 % and 70 % for the 12- and 21-GHz band, respectively.