An Approach of Shaping Offset Dual Reflector Antennas by Controlling Location of Caustic for Local Dual Reflector System

Abstract

This paper presents a shaping method for offset dual reflector antennas. The shaping method solves nonlinear equations to obtain an electrically small local dual reflector surface section. A shaped offset dual reflector antenna surface is created by combining them and the desired aperture distribution that is controlled by the location of caustic for each local dual reflector system. In shaping dual reflectors, the principles of geometrical optics (GO), such as conservation of power and Snell's law, have been widely used. In addition, geometrical properties of parabolic main reflector and either elliptic or hyperbolic subreflector surface are used to formulate the shaped surface equations