Simulation and Analysis of SAR Images of Oceanic Shear-Wave-Generated Eddies.

Sensors (Basel)

National Key Lab of Microwave Imaging Technology, Beijing 100190, China.

Published: March 2019

AI Article Synopsis

  • Synthetic Aperture Radar (SAR) is crucial for studying oceanic eddies, but its imaging can be complicated due to various factors, making direct analysis challenging.
  • A simulation method is proposed to better understand shear-wave-generated eddies, using the Burgers-Rott vortex model to create surface current fields for the simulated eddies.
  • The simulated SAR images align well with real SAR imagery, revealing how different radar parameters and wind conditions affect the imaging of ocean eddies.

Article Abstract

Synthetic Aperture Radar (SAR) is widely used in oceanic eddies research. High-resolution SAR images should be useful in revealing eddy features and investigating the eddy imaging mechanism. However, SAR imaging is affected by various radar parameters and environmental factors, which makes it quite difficult to learn directly from SAR eddy images. In order to interpret and evaluate eddy images, developing a proper simulation method is necessary. However, seldom has a SAR simulation method for oceanic eddies, especially for shear-wave-generated eddies, been established. As a step forward, we propose a simulation method for oceanic shear-wave-generated eddies. The Burgers-Rott vortex model is used to specify the surface current field of the simulated eddies. Images are then simulated for a range of different radar frequencies, radar look directions, wind speeds, and wind directions. The results show that the simulated images are consistent with actual SAR images. The effects of different radar parameters and wind fields on SAR eddy imaging are analyzed by qualitative and quantitative methods. Overall, the simulated images produce a surface pattern and brightness variations with characteristics resembling actual SAR images of oceanic eddies.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6479603PMC
http://dx.doi.org/10.3390/s19071529DOI Listing

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