Self-comparison evaluation method of frequency offset uncertainty of fountain clock

Abstract

Provided is a self-comparison assessment method of the frequency deviation uncertainty of a fountain lock. The physical quantity leading to frequency deviation of the fountain lock is changed, the fountain clock is enabled to work in two working states before a parameter is changed and after the parameter is changed in a crossing mode, frequency discrimination signals are respectively collected, and self-comparison uncertainty assessment of the fountain lock is achieved through data processing. According to the self-comparison assessment method of the frequency deviation uncertainty of the fountain lock, an outside reference lock and a phase comparator are of no need, the risk of influencing assessment work caused by breakdowns of the reference lock is avoided, the influence on the fountain lock caused by the frequency variation of the outside reference lock self in a traditional comparison method is removed, and the assessment precision of the frequency deviation uncertainty is improved.

Description

technical field [0001] The invention relates to a fountain atomic clock, in particular to a self-comparison evaluation method for the frequency uncertainty of a fountain atomic clock (hereinafter referred to as a fountain clock). Background technique [0002] Atomic clocks are instruments for measuring time. Its working principle is that the microwave signal output by the local oscillator 1a is multiplied all the way and then input to the microwave cavity 4b of the atomic clock to interact with the atoms. The atomic system acts as a frequency discriminator. After changing into a voltage signal, the local oscillator 1a is locked by the servo control 5a, and the other frequency signal output by the local oscillator 1a is used as an atomic frequency standard signal, and an accurate time signal is obtained through correction and processing. [0003] The instantaneous output frequency of an atomic clock can be written as: v(t)=v 0 (1+ε+y(t)), where v 0 Corresponding to the tra...

AI Technical Summary

Problems solved by technology

[0005] The traditional atomic clock frequency shift and frequency shift uncertainty evaluation process requires an external reference clock 2c and a phase comparator 5c, which increases the difficulty of the evaluation work. If there is a problem with the reference clock 2c during the actual experiment, it will seriously affect the follow-up evaluation work. conduct

On the other hand, the accuracy of the frequency shift uncertainty evaluation results obtained by the traditional evaluation method is affected by the performance of the reference clock. The Alan variance is the overall result of the reference clock and the atomic clock. There is frequency drift during the long-term operation of the hydrogen clock, which limits the frequency shift uncertainty. Degree of Assessment Accuracy

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