Journal of Applied Physics

Small−signal analysis of the gain and noise performance of the Josephson mixer

Serag E.−D. E.−S. Habib, S. Dmitrevsky

Published Feb 1, 1975• 3 citations

Abstract

The behavior of the voltage−biased Josephosn junction coupled to a general external circuit is studied in the small−signal limit. The Josephson relations are formulated in the frequency domain in the form of an infinite set of difference equations relating the current and voltage amplitudes of different frequency components. The results are subsequently utilized to develop a general theory of the self−oscillating Josephson mixer, including noise. The noise temperature and conversion gain of the mixer are derived taking into consideration the image frequency response. A comparison is made between the operation of the negative−resistance converter in the SC regime and its operation in the OC regime.

DOI: 10.1063/1.321612

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