Joint Timekeeping of Navigation Satellite Constellation with Inter-Satellite Links
Abstract
:1. Introduction
2. Joint Timekeeping Framework
2.1. Traceability by Prediction
2.2. Establishment of ISLT
3. ISLT Timescale Algorithm
3.1. Basic ISLT Timescale Equation
3.2. Inter-Satellite Time Comparison
3.3. Short-Term Prediction of Clock Deviation
3.4. Optimal Weights
4. Performance Evaluation of ISLT
4.1. Clock Noise Identification
4.2. Inter-Satellite Clock Deviations
4.3. Frequency Stability Analysis
4.4. Predictability Improvement
5. Summary and Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Serial Number | Satellite PRN | Nominal Clock |
---|---|---|
1 | C19 | Rb |
2 | C20 | Rb |
3 | C21 | Rb |
4 | C22 | Rb |
5 | C26 | PHM |
6 | C27 | PHM |
7 | C29 | PHM |
8 | C30 | PHM |
9 | C37 | Rb |
PRN | Noise Diffusion Coefficients | ||
---|---|---|---|
C19 | 2.38 × 10−12 | 5.66 × 10−16 | / 1 |
C20 | 3.42 × 10−12 | 1.82 × 10−15 | / |
C21 | 3.02 ×10−12 | 1.41 × 10−15 | / |
C22 | 2.68 ×10−12 | 1.67 × 10−15 | / |
C26 | 2.50 × 10−12 | / | / |
C27 | 1.78 × 10−12 | / | / |
C29 | 1.70 × 10−12 | / | / |
C30 | 1.86 × 10−12 | / | / |
C37 | 5.05 × 10−12 | 2.05 × 10−15 | / |
ISLT Symbol | Clock Ensemble |
---|---|
ISLT | All the nine satellite clocks |
ISLT1 | All the five Rb clocks |
ISLT2 | All the four PHMs |
ISLT3 | C19 C20 C21 C22 C26 C27 C29 C30 |
ISLT4 | C19 C20 C21 C22 C26 C29 C30 C37 |
PRN | Predicting RMS (ns) | PRN | Predicting RMS (ns) |
---|---|---|---|
C19 | 0.25 | C27 | 0.27 |
C20 | 0.37 | C29 | 0.33 |
C21 | 0.36 | C30 | 0.35 |
C22 | 0.40 | C37 | 0.80 |
C26 | 0.46 | ISLT | 0.18 |
PRN | Predicting RMS (ns) | PRN | Predicting RMS (ns) |
---|---|---|---|
C19 | 1.45 | C27 | 1.16 |
C20 | 2.73 | C29 | 1.29 |
C21 | 2.78 | C30 | 1.30 |
C22 | 2.61 | C37 | 4.67 |
C26 | 2.28 | ISLT | 1.05 |
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Sun, L.; Huang, W.; Gao, S.; Li, W.; Guo, X.; Yang, J. Joint Timekeeping of Navigation Satellite Constellation with Inter-Satellite Links. Sensors 2020, 20, 670. https://doi.org/10.3390/s20030670
Sun L, Huang W, Gao S, Li W, Guo X, Yang J. Joint Timekeeping of Navigation Satellite Constellation with Inter-Satellite Links. Sensors. 2020; 20(3):670. https://doi.org/10.3390/s20030670
Chicago/Turabian StyleSun, Leyuan, Wende Huang, Shuaihe Gao, Wei Li, Xiye Guo, and Jun Yang. 2020. "Joint Timekeeping of Navigation Satellite Constellation with Inter-Satellite Links" Sensors 20, no. 3: 670. https://doi.org/10.3390/s20030670
APA StyleSun, L., Huang, W., Gao, S., Li, W., Guo, X., & Yang, J. (2020). Joint Timekeeping of Navigation Satellite Constellation with Inter-Satellite Links. Sensors, 20(3), 670. https://doi.org/10.3390/s20030670