Principles and conclusions on synthesis of offset dual-reflector antennas and dual-reflector feeds for fixed reflectors

A method for synthesizing offset dual-reflector antennas by using geometrical optics (GO) has been introduced by P.-S. Kildal (1988, 1989), in which the synthesis can be performed by solving linear nondifferential equations. The method has been extended to synthesize a dual-reflector feed for the Arecibo telescope and to elliptical apertures. The author gives an overview of the synthesis method and explains how it differs from other approaches based on differential equations. The overview focuses on principles and conclusions.<>