Waveguide-to-microstrip transition at G-band using elevated E-plane probe

A rectangular waveguide-to-microstrip transition operating at G-band is presented. The E-plane probe, used in the transition, is fabricated on semi-insulating gallium arsenide (SI-GaAs) and it is elevated on the substrate. This configuration reduces interaction with semiconductor material. The elevated probe is suitable for direct integration with monolithic microwave integrated circuits. Measured results show S₁₁ better than -10dB between 150 and 200GHz and S₂₁==4dB at centre band (180GHz) for two transitions in back-to-back configuration.