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arXiv · 2403.18419

Frequency Stable Microwave Sapphire Oscillators

Eugene N. Ivanov·Michael E. Tobar
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Abstract

We show that state-of-the-art phase noise and high frequency stability could be simultaneously achieved in a microwave oscillator based on the sapphire-loaded cavity resonator. The 9 GHz sapphire oscillator was constructed with the SSB phase noise close to -170 dBc/Hz at an offset frequency of 10 kHz and fractional frequency instability less than 2 10$^{-13}$ for integration times from 5 to 50 s. In this work, we focus on the technique for phase-referencing the microwave sapphire oscillator to a stable radio-frequency source. We also discuss the suppression of the fast phase fluctuations of the microwave signal due to its transmission through the high-Q resonator.

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Eugene N. Ivanov, Michael E. Tobar. 2024-03-27. Frequency Stable Microwave Sapphire Oscillators. https://doi.org/10.1109/lmwt.2023.3318530

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