A Parallel Plate Ultrawideband Multibeam Microwave Lens Antenna

An ultrawideband multibeam microwave lens antenna operating from 8 to 18 GHz is proposed. The antenna consists of four excitation ports connected to a parallel plate waveguide filled with a cylindrical dielectric slab, which serves as a lens in order to modify the cylindrical wavefront launched by the excitation ports. The output of the lens is a plane wave guided to a radiation aperture with a linear tapered flare. Four distinct fan-beams covering 40° in the azimuth plane with an elevation beamwidth of 30° and a minimum gain of 15 dBi have been achieved. The main advantages of our design include its relative simplicity, ease of fabrication, having a low profile, not requiring an antenna feed, and high-power handling capability. The design procedure is presented together with the optimization procedures. The proposed structure has been simulated with the CST software and fabricated. There is an excellent agreement between the simulation and measurement results.