Improvements in Schottky harmonic and sub-harmonic mixers for use up to 900GHz

Harmonic mixers for high frequencies have been available for many years but conversion loss has always been relatively high and usually with many dips in the frequency response. There are many devices covering the lower waveguide bands, but relatively little above 110GHz. As part of Rohde & Schwarz´s new line of VNA extenders, RPG Radiometer Physics has designed a new range of waveguide harmonic mixers, covering from 24.5 to 900GHz with unsurpassed performance. Part of this work includes complete redesign and fabrication of extremely low parasitic anti-parallel mixer diodes by two independent, competing groups: RAL and ACST together with RPG.