Wideband Inline Coaxial to Ridge Waveguide Transition With Tuning Capability for Ridge Gap Waveguide

An ultra-wideband inline coaxial-to-single ridge waveguide transition is designed to feed the ridge gap waveguide (RGW). The transition covers the frequency band of 11.5 to 33 GHz. This bandwidth cannot be covered by a single RGW. Therefore, two RGWs are manufactured covering two different bands to be used as devices under test. Simulations and measurements of back-to-back transitions have achieved better than 15 dB return loss. In addition, a tuning capability in the transition is simulated using two different commercial simulators showing that the transition may cover up to 40 GHz with over 90% bandwidth to cover the entire Ku, K , and Ka-bands.