Dual-band stepped-impedance transformer to full-height substrate-integrated waveguide

A dual-band transition from conventional to full-height substrate-integrated waveguide (SIW) is introduced. The transition makes use of multiple stepped-impedance sections to achieve dual-band behavior with a high return loss. An equivalent circuit model of the transition is developed, that enables fast optimization. A transition is designed that features two frequency bands at 20GHz and 30 GHz. For verification a back-to-back coplanar-waveguide to full-height SIW transition is fabricated and measured.