Feasibility of mechanical beam scan by movable dielectric blocks in the feeder of a single-layer waveguide array antenna

Abstract

The authors investigate the feasibility of mechanical beam scan by moving dielectric blocks in the feed waveguide of single-layer slotted waveguide arrays. A model using two phase shifters of polycarbonate (er =2.8) is designed and fabricated with three radiating apertures at 12GHz band. 90-degree phase difference is obtained between the adjacent windows to give 11-degree shift of the main beam. Another phase shifter of alumina (er =9.8) gives larger phase shift of 133 degrees corresponding to 15-degree beam tilt.