Rotationally Reconfigurable Single-Element Prism for Enhancing Scanning Flexibility of Risley Prism Antenna System

In this letter, we propose a rotationally reconfigurable single-element prism that is compatible with the typical Risley prism antenna system. It consists of a pair of rotating decentered phase plates operating at 30 GHz. The equivalent prism angle can be continuously changed between 0° and 14° by simply rotating these two phase plates. An all-dielectric low-cost prototype has been designed, fabricated, and measured, which demonstrates the peak realized gain of 21 dBi can be achieved with a gain variation less than 0.9 dB within the reconfigurable angle range of 0°-14°. Besides, the combination of phase distribution of two rotating phase plates can be used as a new mechanism avoiding using first-order paraxial approximation to realize two-dimensional beam scanning.