Design and implementation of an error-compensating subreflector for the NRAO 12-m radio telescope

Author

Mayer, Charles E. ; Emerson, Darrel T. ; Davis, John H.

Author_Institution

Dept. of Electr. Eng., Alaska Univ., Fairbanks, AK, USA

Volume

82

Issue

5

fYear

1994

fDate

5/1/1994 12:00:00 AM

Firstpage

756

Lastpage

762

Abstract

Describes the measurement of the surface shape of the primary reflector of the NRAO 12-m radio telescope and the use of the measurements to machine the shape of a secondary mirror to compensate for the primary reflector errors. The method known as holography was used with the 38.04-GHz transmitter on the geosynchronous Lincoln Experimental Satellite to map the main reflector. The machining of the secondary compensated for the errors in the primary shape, and as a result, at 345 GHz, the axial gain of the instrument was increased by about 50% and the antenna pattern correspondingly improved

Keywords

antenna radiation patterns; antenna testing; error compensation; microwave antennas; microwave holography; radiotelescopes; reflector antennas; submillimetre wave devices; surface topography measurement; 12 m; 200 to 360 GHz; EHF; NRAO 12-m radio telescope; THF; antenna pattern; axial gain; design; error-compensating subreflector; geosynchronous Lincoln Experimental Satellite; holography; implementation; machining; primary reflector; secondary mirror; surface shape; Extraterrestrial measurements; Frequency; Holography; Millimeter wave technology; Observatories; Optical design; Radio astronomy; Satellite broadcasting; Shape measurement; Telescopes;

fLanguage

English

Journal_Title

Proceedings of the IEEE

Publisher

ieee

ISSN

0018-9219

Type

jour

DOI

10.1109/5.284742

Filename

284742