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.