Sea Surface Imaging Simulation for 3D Interferometric Imaging Radar Altimeter

Wang, Zhaoxia; Liu, Yongxin; Zhang, Jie; Fan, Chenqing

doi:10.1109/jstars.2020.3033164

Cited by 5 publications

(2 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the spaceborne InSAR applied to ocean remote sensing, the preset single look resolution is not high, so the synthetic aperture integration time is relatively short [38,46]. In such a short SAR illumination time, the change of the sea surface NRCS with time can be neglected.…”

Section: Analytical Flowchartmentioning

confidence: 99%

An Analytical Method for Dynamic Wave-Related Errors of Interferometric SAR Ocean Altimetry under Multiple Sea States

et al. 2021

View full text Add to dashboard Cite

The spaceborne interferometric synthetic aperture radar (InSAR) is expected to measure the sea surface height (SSH) with high accuracy over a wide swath. Since centimeter-level accuracy is required to monitor the ocean sub-mesoscale dynamics, the high accuracy implies that the altimetric errors should be totally understood and strictly controlled. However, for the dynamic waves, they move randomly all the time, and this will lead to significant altimetric errors. This study proposes an analytical method for the dynamic wave-related errors of InSAR SSH measurement based on the wave spectrum and electromagnetic scattering model. Additionally, the mechanisms of the dynamic wave-related errors of InSAR altimetry are analyzed, and the detailed numerical model is derived. The proposed analytical method is validated with NASA’s Surface Water and Ocean Topography (SWOT) project error budget, and the Root-Mean-Square Errors (RMSEs) are in good agreement (0.2486 and 0.2470 cm on a 0.5 km2 grid, respectively). Instead of analysis for a typical project, the proposed method can be applied to different radar parameters under multiple sea states. The RMSEs of Ka-band under low sea state, moderate sea state, and high sea state are 0.2670, 1.3154, and 6.6361 cm, respectively. Moreover, the RMSEs of X-band and Ku-band are also simulated and presented. The experimental results demonstrate that the dynamic wave-related errors of InSAR altimetry are not sensitive to the frequencies but are sensitive to the sea states. The error compensation method is necessary for moderate and higher sea states for centimetric accuracy requirements. This can provide feasible suggestions on system design and error budget for the future interferometric wide-swath altimeter.

show abstract

Section: Analytical Flowchartmentioning

confidence: 99%

An Analytical Method for Dynamic Wave-Related Errors of Interferometric SAR Ocean Altimetry under Multiple Sea States

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Therefore, the application area of these three methods is limited and cannot be applied to the entire observation data. In addition, there are some other methods tending to reduce the errors through an image de-noising method (Gomez-Navarro et al, 2020;Wang et al, 2021) or data assimilation method (Metref et al, 2019;Metref et al, 2020). Nevertheless, these methods are either limited by prior statistical knowledge of SSH or cannot be adopted in all coverage.…”

Section: Introductionmentioning

confidence: 99%

Overlapping-calibration of wide-swath altimeter baseline errors using two satellites formation flying design

Wang

Gao

et al. 2022

Front. Mar. Sci.

View full text Add to dashboard Cite

The sea surface height (SSH) measured by future wide-swath altimetry satellites contains observation error due to baseline measurement, which is called SSH_Error_Baseline. It is a huge challenge for satellite engineering to maintain such high accuracies of the baseline roll and length in orbit to ensure that the SSH_Error_Baseline can be maintained below 1 cm. Therefore, how to effectively reduce the SSH_Error_Baseline is extremely important. In order to solve the existing problem, an innovative overlapping-calibration method is proposed based on two-satellite formation flight design with overlapping swath. In this study, the differences of SSH data observed by these two satellites in the overlapping area is so small that it can be ignored, and the SSH_Error_Baseline dominates the difference. Then, the baseline parameters of the two satellites can be well estimated by adopting an optimal inverse method. A total of 9 groups of observing system simulation experiments (OSSEs) have been carried out, and they respectively indicate different pessimistic theoretical scenarios of baseline measurement systems. According to the results, this design can effectively reduce the SSH_Error_Baseline in most scenarios. Regarding the advantage of this method, it can be applied to all along-track observation data without requiring the application of additional auxiliary data (i.e. model data, SSH derived from nadir altimetry). Therefore, when two wide-swath altimetry satellites are simultaneously designed, the formation flight scheme proposed in this paper is recommended, especially when the measurements of the baseline cannot meet the expected accuracies.

show abstract

Error analysis and correction of atmospheric disturbance for interferometric imaging radar altimeter

Wang,

Liu,

Zhang

et al. 2024

Advances in Space Research

View full text Add to dashboard Cite

Sea Surface Imaging Simulation for 3D Interferometric Imaging Radar Altimeter

Cited by 5 publications

References 45 publications

An Analytical Method for Dynamic Wave-Related Errors of Interferometric SAR Ocean Altimetry under Multiple Sea States

An Analytical Method for Dynamic Wave-Related Errors of Interferometric SAR Ocean Altimetry under Multiple Sea States

Overlapping-calibration of wide-swath altimeter baseline errors using two satellites formation flying design

Error analysis and correction of atmospheric disturbance for interferometric imaging radar altimeter

Contact Info

Product

Resources

About