Experimental validation of a compact 3D-printed subreflector subsystem for Cassegrain antenna in X-band

Abstract

In this work, a dual-reflector antenna based on a Cassegrain optics with a compact self-supported subreflector is presented to operate at X-band. The feeding subsystem is composed of a subreflector surface, the primary feed and a supporting structure in a single dielectric piece, providing a smart solution. The antenna is fed by a metallic rectangular waveguide with a H-plane transition to a Dielectric Rectangular Waveguide (DRW) finished on a hyperboloid. The designing process presented is based on optical geometrics and it is validated through the manufacture of the Cassegrain antenna. The prototype is fabricated using a 3-D printed technique and the subreflector and main parabolic reflector are metalized by a coating technique. The antenna is simulated and measured obtaining a high agreement on both. The prototype shows good performances in the whole band, validating both the designing technique and the proposed subreflector.