Comparative analysis of cylindrical reflectors of ideal and approximately parabolic shape

Abstract

The performance of a cylindrical reflector antenna of approximately parabolic profile is investigated. The theoretical simulations implement both rigorous method of regularization and physical optics approaches. The complex-point source concept is used to simulate the tapered illumination. The ideal parabolic profile is approximated by a set of 27V straight line segments. A long electric dipole may be moveable from focal line to allow us to examine the impact of focal shifts on the overall performance of the reflector antennas. The methods may be applied to various geometrical and electrical parameters for reflector antennas (D//spl lambda/ /spl les/500, p = F/D /spl ges/ 0.1) but they have been mainly used to perform analysis of the giant cylindrical reflector antenna (Molonglo Observatory Synthesis Telescope, MOST) of the University of Sydney, which is located in Australia near Canberra. It was shown that the design of this antenna is potentially capable of increasing its operating frequency from the present 843 MHz to 2 GHz, without significant loss in forward gain or distortion of the radiation pattern.