Ultra-thin broadband OMT with turnstile junction

This paper presents an ultra-thin broadband waveguide orthomode transducer (OMT) for low profile reflector antenna feed systems. The presented OMT is composed of a turnstile junction with a metallic pyramid, a circular-to-square waveguide step, and thin combiners/dividers. A broadband design of the OMT is performed by applying a circular-to-square waveguide step to obtain good match. An ultra-thin Ku-band OMT fabricated with the aid of the design techniques has realized wideband excellent performance with very low height, that is, VSWR less than 1.18 over 30% bandwidth and reducing the height to 20.2 mm.