A 200 GHz planar diode subharmonically pumped waveguide mixer with state-of-the-art performance

The authors present recent performance data for a 200-GHz subharmonically pumped waveguide mixer using an antiparallel pair of planar air bridge type GaAs Schottky barrier diodes. The measured mixer noise and conversion loss were below those of the best reported whisker contacted or planar diode mixers using the subharmonic pump configuration. In addition, the required local oscillator power was as low as 3 mW for the unbiased diode pair, and significant local oscillator noise suppression was observed. The waveguide design was a prototype for 640 GHz and used a split-block rectangular waveguide with a 2:1 width to height ratio throughout.<>