Beam Scanning Comb-Line Antenna Loading Movable Dielectric Plate

This paper describes a beam scanning antenna loading a movable dielectric plate on a microstrip comb-line antenna. This antenna uses the mechanical system that has the characteristic of an easy structure as well as low costs. The comb, a radiation element, is connected to a microstrip line. The beam direction of the proposed antenna changes according to phase shifts of the microstrip line moving the loaded dielectric plate. First, a guide wavelength change at quasi-millimeter wave band (20GHz) was measured when moving the dielectric plate loaded on the microstrip line. The possibility of the beam scan of the antenna is shown. Next, the comb-line antenna was fabricated and the antenna characteristics were measured. A possible beam scanning angle of 20 degrees was confirmed by moving the plate.