Impact of SAR Azimuth Ambiguities on Doppler Velocity Estimation Performance: Modeling and Analysis
Abstract
:1. Introduction
- (1)
- A model for ocean surface Doppler velocity estimation affected by azimuth ambiguities is developed to investigate how the azimuth ambiguities impact the ocean surface Doppler velocity estimation performance.
- (2)
- Based on the developed model, the estimated bias and standard deviation are derived, and how significant the azimuth ambiguities affect the Doppler velocity estimation performance is quantitatively analyzed.
2. Model for Ocean Surface Doppler Velocity Estimation Affected by Azimuth Ambiguities
3. Statistic of Doppler Velocity Estimation Affected by Azimuth Ambiguities
3.1. Doppler Velocity Estimation Bias Affected by Azimuth Ambiguities
3.2. Standard Deviation of Doppler Velocity Estimates Affected by Azimuth Ambiguities
4. Validation
4.1. Validation with Simulation
4.2. Validation with Chinese GF-3 SAR Data
4.2.1. GF-3 SAR Data Affected by the Right Azimuth Ambiguity
4.2.2. GF-3 SAR Data Affected by the Left and Right Azimuth Ambiguities
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Parameter | Symbol | Value |
---|---|---|
Pulse Repetition Frequency | 1000 Hz | |
Electromagnetic Wavenumber | 118 rad/m | |
Incidence Angle | 45 | |
Power of Main Signal | 1 J | |
Azimuth Ambiguity-to-Signal Ratio | −5 dB, 0 dB, 5 dB |
MAE | RMSE | PCC | ||
---|---|---|---|---|
= −5 dB | BIAS | 0.05 m/s | 0.06 m/s | 0.99 |
STD | 0.01 m/s | 0.01 m/s | 0.99 | |
= 0 dB | BIAS | 0.13 m/s | 0.22 m/s | 0.99 |
STD | 0.04 m/s | 0.19 m/s | 0.81 | |
= 5 dB | BIAS | 0.12 m/s | 0.18 m/s | 0.99 |
STD | 0.01 m/s | 0.01 m/s | 0.99 |
AASR | Method | Bias | Standard Deviation | |||
---|---|---|---|---|---|---|
Theoretical Value | Measured Value | Theoretical Value | Measured Value | |||
ROI1 | −3.03 | OE | −0.56 m/s | −0.55 m/s | 0.23 m/s | 0.20 m/s |
CDE | −0.56 m/s | −0.54 m/s | 0.23 m/s | 0.18 m/s | ||
ROI2 | −1.22 | OE | −0.88 m/s | −0.87 m/s | 0.22 m/s | 0.18 m/s |
CDE | −0.88 m/s | −0.84 m/s | 0.22 m/s | 0.16 m/s | ||
ROI3 | 0.60 | OE | −1.80 m/s | −1.85 m/s | 0.25 m/s | 0.29 m/s |
CDE | −1.80 m/s | −1.83 m/s | 0.25 m/s | 0.27 m/s | ||
ROI4 | −2.53 | OE | −0.50 m/s | −0.52 m/s | 0.22 m/s | 0.24 m/s |
CDE | −0.50 m/s | −0.51 m/s | 0.22 m/s | 0.23 m/s |
AASR | Method | Bias | Standard Deviation | |||
---|---|---|---|---|---|---|
Theoretical Value | Measured Value | Theoretical Value | Measured Value | |||
ROI5 | −5.60 | OE | −3.00 m/s | −3.05 m/s | 0.77 m/s | 0.79 m/s |
CDE | −3.00 m/s | −3.07 m/s | 0.77 m/s | 0.78 m/s | ||
ROI6 | −5.66 | OE | 2.74 m/s | 2.73 m/s | 0.73 m/s | 0.78 m/s |
CDE | 2.74 m/s | 2.75 m/s | 0.73 m/s | 0.78 m/s |
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Sun, K.; Diao, L.; Zhao, Y.; Zhao, W.; Xu, Y.; Chong, J. Impact of SAR Azimuth Ambiguities on Doppler Velocity Estimation Performance: Modeling and Analysis. Remote Sens. 2023, 15, 1198. https://doi.org/10.3390/rs15051198
Sun K, Diao L, Zhao Y, Zhao W, Xu Y, Chong J. Impact of SAR Azimuth Ambiguities on Doppler Velocity Estimation Performance: Modeling and Analysis. Remote Sensing. 2023; 15(5):1198. https://doi.org/10.3390/rs15051198
Chicago/Turabian StyleSun, Kai, Lijie Diao, Yawei Zhao, Wenjia Zhao, Yongsheng Xu, and Jinsong Chong. 2023. "Impact of SAR Azimuth Ambiguities on Doppler Velocity Estimation Performance: Modeling and Analysis" Remote Sensing 15, no. 5: 1198. https://doi.org/10.3390/rs15051198