theoretical analysis of polarization rotation angle in dual reflector antenna

Because of special structure, a dual reflector antenna has beam rotation capability in azimuth and elevation directions. in this structure, the antenna beam can be placed in any point in the space by mechanical movement of twist reflector which it is the most important ability of the antenna. due to the antenna structure, if the polarization of incident wave is linear, it is expected that the polarization of propagated wave is linear and in the direction of desired design. in this paper, for the first time, a nonlinear relation is extracted that it shows the propagated beam polarization has a polarization rotation. this formula is a mathematic closed form relation. these structures are very useful in airborne radar systems.