Diagnostics of a Ka-band discrete spherical lens antenna design

The concept of a discrete spherical lens antenna applied to multi-beam technologies is based on the capability of such a structure to translate different positions on its phase plane to different outcoming directions of the corresponding beams. Usually, these lenses are quite big structures and the feeder must be separated enough from the lens making the simulation of the whole system not an easy task. In fact, the tri-dimensional numerical methods as finite differences or element methods are almost impossible to use since the volume is really enormous. For this kind of problems the moment method or integral equations are preferable. In many cases, the far field pattern is the only result available. In this paper, the calculated far field is used to retrieve the fields on a horn antenna lens aperture plane, allowing antenna design verification. For this purpose, the Sources Reconstruction Method for antenna diagnostics is introduced.