A Two-Step Regional Ionospheric Modeling Approach for PPP-RTK
Abstract
:1. Introduction
2. Regional Ionospheric Modeling Approach
2.1. Slant Ionospheric Delay Extraction
2.2. Two-Step Regional Ionospheric Modeling
3. PPP Processing Strategy
4. Results and Analysis
4.1. Data Description
4.2. Ionospheric Model Accuracy
4.3. PPP-RTK Performance Assessment
4.4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Item | Server | User |
---|---|---|
Frequency | L1, L2, L5 | L1, L2 |
Variance of observations | , where is elevation | Same as server |
Elevation cutoff angle | 7.5° | Same as server |
Satellite orbit and clock | Products from Center for Orbit Determination | Same as server |
Antenna phase center offsets and variations | igs14_2035.atx | Same as server |
Differential code bias | Products from Chinese Academy of Sciences | Same as server |
Receiver coordinates | Estimated as constants | Estimated as white noise |
Tropospheric delay | Dry component corrected by Saastamoinen model with atmospheric pressure , where is the altitude of the station; zenith wet delay estimated as a random walk | Same as server |
Ionospheric delay | Estimated as a random walk | Pseudo-observable variances: |
Receiver clock Ambiguities | Estimated as white noise Estimated as constants | Same as server Same as server |
Ionospheric Model | Convergence Time (min) | RMS (cm) | ||
---|---|---|---|---|
Horizontal | Vertical | Horizontal | Vertical | |
PFM | 2.2 | 4.4 | 1.4 | 2.6 |
PFM/IDWI | 2.1 | 4.2 | 1.4 | 2.5 |
PFM/KI | 1.8 | 4.0 | 1.3 | 2.5 |
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© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
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Xu, Z.; Cai, C.; Pan, L.; Dai, W.; He, B. A Two-Step Regional Ionospheric Modeling Approach for PPP-RTK. Sensors 2024, 24, 2307. https://doi.org/10.3390/s24072307
Xu Z, Cai C, Pan L, Dai W, He B. A Two-Step Regional Ionospheric Modeling Approach for PPP-RTK. Sensors. 2024; 24(7):2307. https://doi.org/10.3390/s24072307
Chicago/Turabian StyleXu, Zhenyu, Changsheng Cai, Lin Pan, Wujiao Dai, and Bei He. 2024. "A Two-Step Regional Ionospheric Modeling Approach for PPP-RTK" Sensors 24, no. 7: 2307. https://doi.org/10.3390/s24072307
APA StyleXu, Z., Cai, C., Pan, L., Dai, W., & He, B. (2024). A Two-Step Regional Ionospheric Modeling Approach for PPP-RTK. Sensors, 24(7), 2307. https://doi.org/10.3390/s24072307