Development of Large Earth-Station Reflector Antennas in Japan

This paper reports an overview of the development of large Earth-station reflector antennas for satellite communication systems in Japan. KDD (now, KDDI) developed a Cassegrain reflector antenna 20 m in diameter at KDD Ibaraki Space Communication Laboratory for Japan´s first Earth station in 1963. This antenna was the first Earth station using a Cassegrain antenna in the world. It was awarded an IEEE Milestone as the “First Transpacific Reception of a Television (TV) Signal via Satellite, 1963” on November 23, 2009. The authors describe design technologies for large Earth-station reflector antennas, including beam-waveguide feed systems and reflector-shaping techniques. These design technologies have contributed tremendously to the popularization and advancement of satellite communication systems. The shaped Cassegrain antenna, fed by a four-reflector beam-waveguide feed, is symbolic of the standard Earth-station antenna all over the world.