A Flexible Measurement Setup for Far-Field Characterization of Reflectarrays Above 200 GHz

Experimental verification of the far-field radiation characteristic of reflectarrays (RAs) in the upper millimeter-wave range is challenging due to the required alignment precision given the small array dimensions. In this work, a measurement setup allowing flexible adjustment of incidence angle and distance between feed antenna and RA is presented. By means of an RA demonstrator operating at 245 GHz, the influence of alignment errors and parasitic effects, such as undesired reflections and clutter, is investigated. The resulting measured radiation pattern recorded in both principal planes exhibits excellent agreement with full-wave simulations of the corresponding RA design.