A Pattern Reconfigurable Antenna for Ka-band Application

In this paper, we present an easy and systematic design approach to realize a dual beam reflector antenna at Ka-band which produces a narrow beam and a wide beam in the boresight. These two beams can be independently selected mechanically or by means of an electronic switching circuit. An exclusive systematic design approach has been presented. Simple mathematical expressions have been used for the design of the reflector and feed horns. The complete antenna has been realized with aluminum and its performances were experimentally validated. It yields approximate to 11.44% impedance bandwidth. It produces approximate to 35.4 dBi gain in the narrow beam mode with a half power beamwidth of approximate to 4.4 degrees x 3.7 degrees and about approximate to 11.3 dBi gain in the wide beam mode with a 3 dB beamwidth of approximate to 46.5 degrees x 46 degrees at 28 GHz. In this present work, the patterns are swapped between a narrow-beam and a wide-beam in the broadside. The ratio of the wide-beamwidth to the narrow-beamwidth is about 11:1, which is substantially different from all earlier investigations.