A broadband perpendicular E‐plane waveguide‐to‐suspended stripline transition Microwave and Optical Technology Letters

A perpendicular E-plane transition between rectangular waveguide (WG) and suspended stripline (SSL) in the Ku-band is presented. The topology of coupling network is studied and design guidelines are provided. A 10-dB return loss bandwidth (BW) of 12% was obtained using a patch resonator on a double-sided single-layer dielectric substrate combined with a cavity behind the resonator of a very shallow depth as low as 1 mm for a compact design. An insertion loss of 0.18 dB at 13.8 GHz was achieved in the measurement of a back-to-back SSL–WG–SSL transition. Comparison of the measured performances with the state-of-the-art WG transitions to SSL shows a 1.5 times improvement in frequency bandwidth and a three times reduction in electrical dimensions.