History
The Cassegrain antenna design was adapted from the Cassegrain telescope, a type of reflecting telescope developed around 1672 and attributed to French priest Laurent Cassegrain. The first Cassegrain antenna was invented and built in Japan in 1963 by NTT, KDDI and Mitsubishi Electric. The 20 meter I-1 antenna operated at 6.4, 4.2, and 1.7 GHz, and was used in October 1963 in the first trans-Pacific satellite television relay experiments.
Closeup of the convex secondary reflector in a large satellite communications antenna in Pleumeur-Bodou, France Cassegrain spacecraft communication antenna in Canberra, Australia, part of NASA's Deep Space Network. The advantage of the Cassegrain design is that the heavy complicated feed structure (bottom) doesn't have to be suspended over the dish. Cassegrain antenna on the Voyager spacecraftRead more about this topic: Cassegrain Antenna
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