DocumentCode :
781361
Title :
Minimization of the plane-wave scattering contribution of inverted-Y strut tripods to the noise temperature of reflector antennas
Author :
Moreira, Fernando J S ; Prata, Aluizio, Jr. ; Thorburn, Michael A.
Author_Institution :
Dept. of Electr. Eng.-Electrophys., Univ. of Southern California, Los Angeles, CA, USA
Volume :
44
Issue :
4
fYear :
1996
fDate :
4/1/1996 12:00:00 AM
Firstpage :
492
Lastpage :
499
Abstract :
The article is concerned with determining the metallic strut cross section of inverted-Y tripods used to minimize the plane-wave scattering contribution to the noise temperature of ground-station reflector antennas and radio telescopes. This is accomplished by numerically optimizing the cross section for minimum ground-noise pickup over the antenna elevation-angle operation range. Advantage is taken of the fact that although the struts´ cross-section perimeter can be comparable to the operation wavelength, their electrical lengths are usually long. This allows the struts´ scattering characteristics to be determined by solving standard two-dimensional field integral equations. The article concentrates on the top strut of an inverted-Y configuration since it is responsible for the dominant ground noise pickup associated with the plane-wave scattering. Numerical simulations are presented to substantiate this fact and a simple and convenient broadband closed-form representation for the minimum-noise top-strut cross section is derived and tested
Keywords :
electromagnetic fields; electromagnetic wave scattering; integral equations; noise; radiotelescopes; reflector antennas; satellite antennas; satellite ground stations; 2D field integral equations; antenna elevation-angle; broadband closed-form representation; cross-section perimeter; ground-station reflector antennas; inverted-Y strut tripods; long electrical lengths; metallic strut cross section; minimum ground-noise pickup; minimum-noise top-strut cross section; noise temperature; numerical simulations; operation wavelength; plane wave scattering minimisation; radio telescopes; reflector antennas; scattering characteristics; two-dimensional field integral equations; Antenna accessories; Antenna radiation patterns; Feeds; Land surface temperature; Propulsion; Radar scattering; Receiving antennas; Reflector antennas; Transmitting antennas; Working environment noise;
fLanguage :
English
Journal_Title :
Antennas and Propagation, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-926X
Type :
jour
DOI :
10.1109/8.489300
Filename :
489300
Link To Document :
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