Abstract
Several SIS quasiparticle mixers have been designed and tested for the frequency range from 80 to 115 GHz. The sliding backshort is the only adjustable RF tuning element. The RF filter reactance is used as a fixed RF matching element. A mixer which uses a single 2×2 μm2 Pb-alloy junction in a quarter-height waveguide mount has a coupled conversion gain of GM(DSB)=2.6±0.5 dB with an associated noise temperature of TM(DSB)=16.4±1.8 K at the best DSB operation point. The receiver noise temperature TR(DSB) is 27.5±0.8 K for the mixer test apparatus. This mixer provides a SSB receiver noise temperature below 50 K over the frequency range from 91 to 96 GHz, the minimum being TR(SSB)=44±4 K. Another mixer with an array of five 5×5 μm2 junctions in series in a full-height wave-guide mount has much lower noise temperature TM(DSB)=6.6±1.6 K, but less gain GM(DSB)=−5.1±0.5 dB.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have