Oscillating circuit with a ring shaped resonator of superconducting material coupled thereto

Abstract

An improved oscillating circuit for use in microwave frequency bands has reduced power loss and is made smaller in vertical size. The local oscillating circuit includes an MMIC oscillator which comprises a FET, and a resonator connected thereto so as to stabilize the oscillating frequency of the oscillator. The resonator is ring-shaped and arranged as close as several .mu.m to several tens of .mu.m to a predetermined position of a micro strip line forming a feedback loop connected to the FET forming the oscillator. Moreover, the resonator is a thin film formed by depositing a high-temperature superconducting material. As exemplary embodiments, YBCO, niobium and the like, can be used as high-temperature superconducting materials. Furthermore, a portion of the micro strip line, closest to the resonator, is concentrically disposed therewith to form a circular arc portion whose central angle is set at 90 degrees.

Dependencies are inferred from the claim text.