| Autor: |
A. H. Worsham, P. F. Goldsmith, N. R. Erickson, Daniel E. Prober, Dag Winkler, N. G. Ugras |
| Rok vydání: |
1991 |
| Předmět: |
|
| Zdroj: |
Nonlinear Superconductive Electronics and Josephson Devices ISBN: 9781461367192 |
| DOI: |
10.1007/978-1-4615-3852-3_6 |
| Popis: |
A broadband waveguide SIS (superconductor-insulator-superconductor) mixer with no adjustable mechanical tuning elements for the 75–110 GHz band was constructed and tested. The design is a demonstration of a prototype receiver element in a focal plane array receiver. The large instantaneous bandwidth was accomplished with a broadband waveguide-to-microstrip transition and a scale-modeled microstripline circuitry. The transition to microstripline consisted of a waveguide single ridge 4-step Chebychev transformer. The last step of the ridge connected the waveguide to the microstripline circuit, which contained the SIS element in parallel with a thin film tuning inductor. The operation was double-sideband (DSB). The typical DSB mixer noise temperature, as measured between 79.5 and 110 GHz, was about 35 to 50 K at band center increasing to about 50–60 K at the band edges. The lowest mixer noise we obtained was 20 K at 80 GHz for a single untuned junction. For some junction geometries, gain was also observed between 80 to 110 GHz, with a maximum of +3 dB (DSB) at 100 GHz. No impedance transformers were used on the intermediate frequency (if) side. For several devices, negative dynamic resistance was observed on the first photon induced step below the gap. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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