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Subreflector extension for improved efficiencies in Cassegrain antennas - GTD/PO analysisBoth offset and symmetric Cassegrain reflector antennas are used in satellite and ground communication systems. It is known that the subreflector diffraction can degrade the performance of these reflectors. A geometrical theory of diffraction/physical optics analysis technique is used to investigate the effects of the extended subreflector, beyond its optical rim, on the reflector efficiency and far-field patterns. Representative numerical results are shown for an offset Cassegrain reflector antenna with different feed illumination tapers and subreflector extensions. It is observed that for subreflector extensions as small as one wavelength, noticeable improvements in the overall efficiencies can be expected. Useful design data are generated for the efficiency curves and far-field patterns.
Document ID
19870033549
Document Type
Reprint (Version printed in journal)
Authors
Rahmat-Samii, Yahya (California Institute of Technology Jet Propulsion Laboratory, Pasadena, United States)
Date Acquired
August 13, 2013
Publication Date
October 1, 1986
Publication Information
Publication: IEEE Transactions on Antennas and Propagation
Volume: AP-34
ISSN: 0018-926X
Subject Category
COMMUNICATIONS AND RADAR
Distribution Limits
Public
Copyright
Other