Characterizing Periodic Variations of Atomic Frequency Standards via Their Frequency Stability Estimates
The onboard atomic frequency standard (AFS) is a crucial element of Global Navigation Satellite System (GNSS) satellites. However, it is widely accepted that periodic variations can influence the onboard AFS. The presence of non-stationary random processes in AFS signals can lead to inaccurate separ...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-06-01
|
| Series: | Sensors |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1424-8220/23/11/5356 |
| _version_ | 1827739169656406016 |
|---|---|
| author | Weiwei Cheng Guigen Nie Jian Zhu |
| author_facet | Weiwei Cheng Guigen Nie Jian Zhu |
| author_sort | Weiwei Cheng |
| collection | DOAJ |
| description | The onboard atomic frequency standard (AFS) is a crucial element of Global Navigation Satellite System (GNSS) satellites. However, it is widely accepted that periodic variations can influence the onboard AFS. The presence of non-stationary random processes in AFS signals can lead to inaccurate separation of the periodic and stochastic components of satellite AFS clock data when using least squares and Fourier transform methods. In this paper, we characterize the periodic variations of AFS using Allan and Hadamard variances and demonstrate that the Allan and Hadamard variances of the periodics are independent of the variances of the stochastic component. The proposed model is tested against simulated and real clock data, revealing that our approach provides more precise characterization of periodic variations compared to the least squares method. Additionally, we observe that overfitting periodic variations can improve the precision of GPS clock bias prediction, as indicated by a comparison of fitting and prediction errors of satellite clock bias. |
| first_indexed | 2024-03-11T02:57:04Z |
| format | Article |
| id | doaj.art-ca899a4503084897b08ecc351309d691 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-11T02:57:04Z |
| publishDate | 2023-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-ca899a4503084897b08ecc351309d6912023-11-18T08:36:03ZengMDPI AGSensors1424-82202023-06-012311535610.3390/s23115356Characterizing Periodic Variations of Atomic Frequency Standards via Their Frequency Stability EstimatesWeiwei Cheng0Guigen Nie1Jian Zhu2School of Transportation, Civil Engineering and Architecture, Foshan University, Foshan 528000, ChinaGNSS Center, Wuhan University, Wuhan 430079, ChinaSchool of Transportation, Civil Engineering and Architecture, Foshan University, Foshan 528000, ChinaThe onboard atomic frequency standard (AFS) is a crucial element of Global Navigation Satellite System (GNSS) satellites. However, it is widely accepted that periodic variations can influence the onboard AFS. The presence of non-stationary random processes in AFS signals can lead to inaccurate separation of the periodic and stochastic components of satellite AFS clock data when using least squares and Fourier transform methods. In this paper, we characterize the periodic variations of AFS using Allan and Hadamard variances and demonstrate that the Allan and Hadamard variances of the periodics are independent of the variances of the stochastic component. The proposed model is tested against simulated and real clock data, revealing that our approach provides more precise characterization of periodic variations compared to the least squares method. Additionally, we observe that overfitting periodic variations can improve the precision of GPS clock bias prediction, as indicated by a comparison of fitting and prediction errors of satellite clock bias.https://www.mdpi.com/1424-8220/23/11/5356GPS satellite clocksperiodic variationsfrequency stabilityAllan varianceHadamard variance |
| spellingShingle | Weiwei Cheng Guigen Nie Jian Zhu Characterizing Periodic Variations of Atomic Frequency Standards via Their Frequency Stability Estimates Sensors GPS satellite clocks periodic variations frequency stability Allan variance Hadamard variance |
| title | Characterizing Periodic Variations of Atomic Frequency Standards via Their Frequency Stability Estimates |
| title_full | Characterizing Periodic Variations of Atomic Frequency Standards via Their Frequency Stability Estimates |
| title_fullStr | Characterizing Periodic Variations of Atomic Frequency Standards via Their Frequency Stability Estimates |
| title_full_unstemmed | Characterizing Periodic Variations of Atomic Frequency Standards via Their Frequency Stability Estimates |
| title_short | Characterizing Periodic Variations of Atomic Frequency Standards via Their Frequency Stability Estimates |
| title_sort | characterizing periodic variations of atomic frequency standards via their frequency stability estimates |
| topic | GPS satellite clocks periodic variations frequency stability Allan variance Hadamard variance |
| url | https://www.mdpi.com/1424-8220/23/11/5356 |
| work_keys_str_mv | AT weiweicheng characterizingperiodicvariationsofatomicfrequencystandardsviatheirfrequencystabilityestimates AT guigennie characterizingperiodicvariationsofatomicfrequencystandardsviatheirfrequencystabilityestimates AT jianzhu characterizingperiodicvariationsofatomicfrequencystandardsviatheirfrequencystabilityestimates |