Performance is equalized in horizontal and vertical polarizations.

The figure shows a dual-beam, dual- polarization Ku-band antenna, the reflector of which comprises an assembly of small reflectarrays arranged in a piecewise-planar approximation of a parabolic reflector surface. The specific antenna design is intended to satisfy requirements for a wide-swath spaceborne radar altimeter, but the general principle of piecewise-planar reflectarray approximation of a parabolic reflector also offers advantages for other applications in which there are requirements for wide-swath antennas that can be stowed compactly and that perform equally in both horizontal and vertical polarizations.