Title :
Spectral-domain analysis of harmonic effects in superconducting quasiparticle mixers
Author :
Withington, Stafford ; Kollberg, Erik L.
Author_Institution :
Dept. of Radio & Space Sci., Chalmers Univ., of Technol., Goteborg, Sweden
fDate :
1/1/1989 12:00:00 AM
Abstract :
An algorithm was developed for calculating the harmonic performance of superconducting quasiparticle millimeter-wave mixers. The scheme uses harmonic balance to determine the steady-state waveform of the large-amplitude voltage which is induced across the tunnel junction by the local oscillator source. A key feature of the algorithm is that the large-signal tunneling-current calculations are done in the frequency domain rather than in the time domain, and this approach leads to numerically efficient computer simulations. The superiority of the spectral-domain method is particularly pronounced when modeling mixers that incorporate high-quality tunnel junctions with very sharp DC nonlinearities. A simplified mixer simulation was performed to determine the range of ωCR products for which harmonic effects are likely to be important
Keywords :
equivalent circuits; frequency-domain analysis; harmonics; mixers (circuits); solid-state microwave circuits; superconducting junction devices; DC nonlinearities; MM-wave devices; frequency domain; harmonic balance; harmonic effects; large-amplitude voltage; large-signal tunneling-current calculations; local oscillator source; microwave type; millimeter-wave mixers; numerically efficient computer simulations; small signal analysis; spectral-domain method; steady-state waveform; superconducting quasiparticle mixers; tunnel junction; Chromium; Computational modeling; Computer simulation; Frequency domain analysis; Harmonic analysis; Josephson junctions; Local oscillators; Millimeter wave technology; Steady-state; Voltage-controlled oscillators;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on