A Least Squares Extrapolation Model for UT1-UTC Prediction Method with Consideration of the Edge-effect

Lei Yu; Zhao Danning; Cai Hongbing

Astronomical Research and Technology > 2018 > 15(3): 302-307.

Lei Yu, Zhao Danning, Cai Hongbing. A Least Squares Extrapolation Model for UT1-UTC Prediction Method with Consideration of the Edge-effect[J]. Astronomical Research and Technology, 2018, 15(3): 302-307.

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A Least Squares Extrapolation Model for UT1-UTC Prediction Method with Consideration of the Edge-effect

Lei Yu^1,2,
Zhao Danning^1,2,3,
Cai Hongbing^1,2

1. National Time Service Center, Chinese Academy of Sceinces, Xi'an 710600, China;
2. Key Laboratory of Time and Frequency Primary Standards, Chinese Academy of Sciences, Xi'an 710600, China;
3. University of Chinese Academy of Sciences, Beijing 100049, China

More Information

Received Date: December 13, 2017
Revised Date: December 24, 2017
Available Online: November 20, 2023

Graphical Abstract

Abstract

Abstract

The prediction accuracy of UT1-UTC can be easily affected by the edge distortion of least squares (LS) fitting time-series, referred to as edge-effect in the data-processing domain, when periodic oscillations and residuals are separated by LS fitting. In order to alleviate the edge-effect, the original UT1-UTC time-series is first extended on both boundaries by using a time-series analysis model in this paper. A LS extrapolation model is then set up using the extended time-series. Finally UT1-UTC predictions are obtained by employing the combination of the edge-effect correlated least squares (ECLS) model and a stochastic predication technology such as neural network (NN). The numerical experiments demonstrate that the edge-effect can be noticeably alleviated with the developed method. In addition, the accuracy of the UT1-UTC short-term predictions is comparable with that by the conventional LS extrapolation-based prediction algorithm. However, the medium- and long-term predictions are significantly more accurate than those obtained by the proposed ECLS extrapolation-based prediction solution.
- UT1-UTC prediction,
- Prediction model,
- Least squares (LS),
- Edge-effect,
- Edge extension

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References (10)

References

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