Phase synthesis of reflectarray subreflector in dual-reflector configuration for beam scanning applications

A phase synthesis technique for a reflectarray as subreflector in a dual-reflector configuration is proposed for beam scanning applications. The technique applies the analysis of the antenna in receive mode to determine the phase-shift distribution on the reflectarray that produces a beam with the required deflecting angle. The synthesis technique has been applied to a dual reflector antenna comprising a 1-metre main parabolic reflector and a 22-cm sub-reflectarray, to produce a beam scanning at 12 GHz in a range from −6 to +6 degrees. The phase distributions and radiation patterns are obtained for several scanning angles.