Abstract: A re-polarization means for generating circular polarized electro-magnetic waves using single or multi-layer lattice structure mounted in front of a radiation aperture with the lattice structure comprising a plurality of conductors which extend parallel to each other and/or meander shaped and wherein the lattice structure has one or more additional layers which are closer to the radiation aperture and which has a plurality of parallel conductors but that are inclined by an angle of 45.degree. relative to the direction of the conductors mounted on the other layers which meander. Additionally, orthogonal polarization suppression is achieved with the apparatus of the invention. The invention can be applied to a radom of a target tracking radar antenna, for example.

Abstract: Means for re-polarizing and generating circularly polarized waves using a single or multi-layer lattice structure which is placed in front of a radiation aperture with the lattice structure consisting of a plurality of conductors extending in the form of lines which meander and might be rectangular combinations or the like. With a lattice, a polarization conversion into circular polarization and the suppression of orthogonal polarization components is simultaneously achieved by providing that the meandering lines 4 extend in a direction such that the meander lines have an angle of 45.degree. at every location with respect to the respective E vectors of the linearly polarized E-vector fields at such locations. The re-polarization means can be used as a Radome of a target tracking radar antenna.