Design of a 118-GHz sub-harmonic mixer using foundry diodes

The paper presents the design and fabrication of a low-loss fixed-tuned 118 GHz subharmonically pumped mixer, using commercially available GaAs Schottky barrier diodes flip-chipped onto a suspended microstrip circuit. The simulation performance of the mixer exhibits a double side band (DSB) conversion loss below 10 dB over the range of 113-123-GHz, with 6 mW of local oscillator (LO) power. At 118 GHz, a DSB conversion loss of 12.6 dB is measured with 8 mW of LO power.