Ocean wave parameter extraction method based on shape-from-shading (SFS) technology

Abstract

The invention discloses an ocean wave parameter extraction method based on an SFS technology. According to the Lambertian scattering law, relations between the relative echo intensity and the incident angle, the direction slope and the distance slope are derived, the SFS technology and transformation formulas of polarization direction angles caused by the direction slope and the distance slope of the ocean surface are combined to solve slope values of pixels of the ocean surface, and a direction slope spectrum and a distance slope spectrum are obtained respectively by using fast Fourier transform. Spectral peak positions are searched, wave number vector information is acquired, 180-degree ocean wave direction blur is eliminated, ocean wave propagation directions are determined, the wavelength is calculated according to relations between the wave number and the wavelength, the ocean wave period is solved through ocean wave dispersion relations, and the significant wave height is calculated by the average slope and the wavelength. According to the ocean wave parameter extraction method, ocean wave spectrum inversion can be performed without a modulation transfer function, parameters such as the ocean wavelength, the period, the significant wave height and the ocean wave direction can be extracted, and the method is applicable to images acquired by high-frequency radars.

Description

technical field [0001] The invention discloses a method for extracting sea wave parameters based on shadow recovery shape technology, in particular to a method for extracting sea surface effective wave height, cycle, wavelength and wave direction parameters, and belongs to the technical field of marine survey and marine environment monitoring. Background technique [0002] Wave parameter inversion technology is the core of marine environment monitoring and marine meteorological forecast data assimilation, and it is also the focus of current ocean remote sensing monitoring. The marine community obtains wave parameters mainly through on-site measurements and remote sensing measurements. Among them, on-site measurement can only obtain sporadic and a small number of wave parameters. For the vast ocean, only airborne and satellite remote sensing observations can meet human needs for monitoring and forecasting ocean waves. At present, the most practical and relatively more mature...

AI Technical Summary

Problems solved by technology

However, the current methods of parameter extraction using full-polarization SAR have different limitations. One is that it is not suitable for images obtained by high-frequency radar, and the other is that it needs to rely on the modulation transfer function.

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