Wideband flat short foci lens antenna

Abstract

A wideband lens antenna lens of reduced thickness includes a lens antenna constructed of a flat inhomogeneous dielectric plate. A radiation source is located on one side of the dielectric plate and a reflector is located on another side of the dielectric plate opposite the radiation source. In operation, signals generated by the radiation source of arbitrary polarization pass through the dielectric plate, are reflected by the reflector, and pass back through the dielectric plate a second time before being emitted from the lens antenna. In such a case, the provision of the reflector allows the thickness of the dielectric plate to be cut in half as compared with conventional lens antennas. If the signals supplied by the radiation source are linearly polarized, a polarization transformer is provided on the same surface of the dielectric plate as the radiation source. In operation, the signals are reflected by the reflector back to the polarization transformer, which changes the polarization of the signals while reflecting them back through the dielectric plate. The change in polarization allows the signals to pass through the reflector and be emitted from the antenna structure. In such a case, the thickness of the dielectric plate can be reduced to one-fourth the thickness required in conventional lens antennas.

Dependencies are inferred from the claim text.