Estimating Significant Wave Height from SAR with Long Integration Times
Abstract
:1. Introduction
2. Estimating Significant Wave Height from SAR with Long Integration Times
2.1. Pre-Processing
2.2. Azimuth Cutoff Calculation
2.3. Ocean Wave Refocusing
2.4. Scanning Distortion Calibration
2.5. Wavelength and Propagation Direction Calculation of nth Ocean Waves
2.5.1. Wavelength Calculation of nth Ocean Wave
2.5.2. Propagation Direction Calculation of nth Ocean Wave
2.5.3. 180° Ambiguity Removal of Wave Propagation Direction
2.6. Significant Wave Height Estimation
3. Experiments of Estimating Significant Wave Height from SAR with Long Integration Times
3.1. Case 1-Invisible Ocean Waves from SAR with Long Integration Times
3.2. Case 2-Multiple Ocean Waves from SAR with Long Integration Times
3.2.1. Experiment of Significant Wave Height Estimation of the First Ocean Waves
3.2.2. Experiment of Significant Wave Height Estimation of the Second Ocean Wave
4. Validation of the Experimental Results with ECMWF and Sensitivity Analysis
4.1. Validation of the Experimental Results with ECMWF
4.2. Sensitivity Analysis of Significant Wave Height Estimation
4.2.1. Sensitivity Analysis of Significant Wave Height to Azimuth Cutoff
4.2.2. Sensitivity Analysis of Significant Wave Height to Wavelength of Ocean Waves
4.2.3. Sensitivity Analysis of Significant Wave Height to Propagation Direction of Ocean Waves
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Parametric Name | Parametric Symbol | Parametric Value |
---|---|---|
Radar wavelength (m) | 0.5 | |
Platform height (m) | H | 8600 |
Slant range of scene center (m) | 18,000 | |
Platform speed (m/s) | V | 122 |
Integration Times (s) | 23 |
Parametric Name | Parametric Symbol | Parametric Value |
---|---|---|
Radar wavelength (m) | 0.23 | |
Platform height (m) | H | 8100 |
Slant range of scene center (m) | 13,000 | |
Platform speed (m/s) | V | 117 |
Integration Times (s) | 6 |
Case 1-Invisible Waves | Case 2-Two Wave Systems | ||
---|---|---|---|
SAR acquisition time (UTC) | 2014.10.11 01:22 | 2014.9.14 01:29 | |
SAR image central location | |||
Corresponding time of ECMWF (UTC) | 2014.10.11 01:00 | 2014.9.14 01:00 | |
SWH from SAR image (m) | 1.51 | 0.45 | 0.40 |
Corresponding SWH from ECMWF (m) | 1.52 | 0.51 | 0.30 |
Parametric Name | Parametric Symbol | Parametric Value |
---|---|---|
Azimuth cutoff (m) | 90 | |
Wavelength of ocean waves (m) | 240 | |
Propagation direction of ocean waves (°) | 300 |
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Zhao, Y.; Chong, J.; Li, Z.; Wei, X.; Diao, L. Estimating Significant Wave Height from SAR with Long Integration Times. Appl. Sci. 2022, 12, 2341. https://doi.org/10.3390/app12052341
Zhao Y, Chong J, Li Z, Wei X, Diao L. Estimating Significant Wave Height from SAR with Long Integration Times. Applied Sciences. 2022; 12(5):2341. https://doi.org/10.3390/app12052341
Chicago/Turabian StyleZhao, Yawei, Jinsong Chong, Zongze Li, Xianen Wei, and Lijie Diao. 2022. "Estimating Significant Wave Height from SAR with Long Integration Times" Applied Sciences 12, no. 5: 2341. https://doi.org/10.3390/app12052341
APA StyleZhao, Y., Chong, J., Li, Z., Wei, X., & Diao, L. (2022). Estimating Significant Wave Height from SAR with Long Integration Times. Applied Sciences, 12(5), 2341. https://doi.org/10.3390/app12052341