Characterization of BDS Multipath Effect Based on AT-Conv-LSTM Network
Abstract
:1. Introduction
2. Multipath Analysis Method
2.1. Multipath Extraction
2.2. Multipath Analysis Method Based on Different Indicators
3. Multipath Characterization with the AT-Conv-LSTM Network
3.1. AT-Conv-LSTM Network
3.2. Attention Mechanism Considering Multiple Indicators
3.3. Model Training and Evaluation
4. Results
4.1. Data Description
4.2. Code Multipath Analysis
4.3. Correlation Analysis of Nadir Angles and Code Multipath
4.4. Comparison of AT-Conv-LSTM with Other Methods
5. Discussion
6. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Items | Strategies |
---|---|
Observations | BDS: B1/B3 |
Sampling rate | 30 s |
Elevation cutoff | 7° |
Parameter estimator | Kalman filter |
Satellite orbits and clocks | WHU MGEX precise orbit (5 min interval) and clock (30 s interval) products |
Carrier phase windup | Corrected using the external model |
Tidal load | Corrected using the IERS convention model |
Relativity effects, Earth rotation | Corrected using the external model |
Satellite and receiver antenna Phase center | Corrected with igs14.atx |
Slant ionospheric delays | Estimated as random-walk noise parameters () |
Tropospheric delays | The mapping function utilized for line of sight direction is global mapping function, zenith hydrostatic delays are corrected using the Saastamoinen model, zenith wet delays are estimated as random-walk noises () |
Receiver clocks | Estimated as white noises |
Phase ambiguities | Estimated as float constants |
Station coordinates | Estimated as day constants |
Stochastic model | Elevation-dependent weighting (prior variance as 0.003 and 0.3 m for code and phase observations) |
BDS-3 System | B1I | B1C | B2a | B2b | B3I |
---|---|---|---|---|---|
Frequency (MHz) | 1561.098 | 1575.420 | 1176.450 | 1207.140 | 1268.520 |
Chip Rate (Mcps) | 2.046 | 1.023 | 10.23 | 10.23 | 10.23 |
Wavelength (cm) | 19.20 | 19.03 | 25.48 | 24.83 | 23.63 |
Items | Strategies |
---|---|
Station Name | JFNG |
Localization | China |
Latitude | 30.51557° |
Longitude | 114.49102° |
Receiver | TRIMBLE ALLOY—6.20 |
Antenna Type | TRM59800.00 |
Constellations | GPS + GLO + GAL + BDS + QZSS + IRNSS + SBAS |
PRN | Uncorrected | MHM-Corrected | T-MHM-Corrected | SF-Corrected | AT-Conv-LSTM-Corrected | |||||
---|---|---|---|---|---|---|---|---|---|---|
MAE (m) | RMSE (m) | MAE (m) | RMSE (m) | MAE (m) | RMSE (m) | MAE (m) | RMSE (m) | MAE (m) | RMSE (m) | |
C22 | 0.3322 | 0.5596 | 0.1581 | 0.6154 | 0.0143 | 0.5731 | 0.0050 | 0.6608 | 0.0681 | 0.4447 |
C23 | 0.3322 | 0.5596 | 0.1797 | 0.6175 | 0.0143 | 0.5731 | 0.0050 | 0.6608 | 0.0681 | 0.4747 |
C36 | 0.3620 | 0.3809 | 0.1827 | 0.4225 | 0.0529 | 0.2952 | 0.0587 | 0.5641 | 0.0812 | 0.3615 |
C38 | 0.0340 | 0.3364 | 0.1106 | 0.3932 | 0.0020 | 0.3588 | 0.0340 | 0.3364 | 0.0480 | 0.4118 |
C39 | 0.0614 | 0.2766 | 0.0505 | 0.3501 | 0.0191 | 0.2686 | 0.0447 | 0.3514 | 0.0241 | 0.2386 |
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Sun, J.; Tang, Z.; Zhou, C.; Wei, J. Characterization of BDS Multipath Effect Based on AT-Conv-LSTM Network. Remote Sens. 2024, 16, 73. https://doi.org/10.3390/rs16010073
Sun J, Tang Z, Zhou C, Wei J. Characterization of BDS Multipath Effect Based on AT-Conv-LSTM Network. Remote Sensing. 2024; 16(1):73. https://doi.org/10.3390/rs16010073
Chicago/Turabian StyleSun, Jie, Zuping Tang, Chuang Zhou, and Jiaolong Wei. 2024. "Characterization of BDS Multipath Effect Based on AT-Conv-LSTM Network" Remote Sensing 16, no. 1: 73. https://doi.org/10.3390/rs16010073