Method of moments analysis of symmetric dual reflector antennas with feeds

Small symmetric dual reflector antennas have low efficiencies because of conflicting requirements for the subreflector and feed. Low efficiency is more pronounced for antenna configurations with main reflector diameters less than 50 times its operating wavelength. the subreflector and feed geometry must be small to reduce blockage but yet large enough to be an efficient scatterer. It may be possible to compensate for this by tuning the feed and subreflector. that is, by proper choice of the antenna geometry and dimensions and by using low-blockage feeds, the efficiency may be enhanced. Existing computer codes have been modified in this thesis to reflect these changes in antenna feeds in order to optimize the antenna efficiency. A feed system consisting of a fed dipole in the presence of parasitic elements has resulted in an efficiency of 55%. Other untested feed configurations may produce even higher efficiencies.http://archive.org/details/methodofmomentsa00ordoLieutenant, United States NavyApproved for public release; distribution is unlimited