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arXiv · 1004.0775

Stability measurements of microwave frequency synthesis with liquid helium cooled cryogenic sapphire oscillators

J. G. Hartnett·D. L. Creedon·D. Chambon·G. Santarelli
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Abstract

We report on the evaluation of microwave frequency synthesis using two cryogenic sapphire oscillators developed at the University of Western Australia. A down converter is used to make comparisons between microwave clocks at different frequencies, where the synthesized signal has a stability not significantly different from the reference oscillator. By combining the CSO with a H-maser, a reference source of arbitrary frequency at X-band can be synthesized with a fractional frequency stability of sub-$4 \times 10^{-15}$ for integration times between 1 s and 10,000 s.

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J. G. Hartnett, D. L. Creedon, D. Chambon, G. Santarelli. 2010-04-06. Stability measurements of microwave frequency synthesis with liquid helium cooled cryogenic sapphire oscillators. https://arxiv.org/abs/1004.0775

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