Experimental results on a 9.2-GHz superconducting cavity stabilized oscillator
Abstract
The experimental results of the frequency stabilization of a Gunn diode oscillator by a 9.2-GHz TM(010) niobium superconducting cavity (unloaded Q = 4 x 10 to the 8th) are described. The frequency shift of the superconducting cavity stabilized oscillator (SCSO) induced by the mismatch of a square-law detector in the discriminator is studied, and, by improving this problem, the fractional frequency fluctuation due to room-temperature changes is reduced to less than 1 x 10 to the -13th/C. The frequency stability of the SCSO is measured by comparing it with the auto-tuned hydrogen maser. The frequency stability of sigma y(tau) reached 1.4 x 10 to the -14th at tau = 500 s, after subtraction of the linear frequency drift. The measured S/N of the discriminator shows that even with the comparatively low Q cavity, short-term frequency stability of 1.4 x 10 to the -14th/sq rt tau is achieved in the SCSO. The measured acceleration sensitivity of the SCSO was 6.5 x 10 to the -8th/g for the vibration frequency less than 80 Hz.
- Publication:
-
IEEE Transactions on Instrumentation Measurement
- Pub Date:
- March 1987
- DOI:
- 10.1109/TIM.1987.6312620
- Bibcode:
- 1987ITIM...36....2K
- Keywords:
-
- Cavity Resonators;
- Frequency Stability;
- Gunn Diodes;
- Microwave Oscillators;
- Resonant Frequencies;
- Superconductivity;
- Frequency Shift;
- Noise Spectra;
- Phase Modulation;
- Power Spectra;
- Standing Wave Ratios;
- Electronics and Electrical Engineering