A method for estimating incident angle of sar image

Abstract

The invention discloses an SAR image incident angle estimation method. The method comprises the following steps: firstly preprocessing an SAR image, acquiring an image section containing a building target from an SAR slang-range image, selecting two bright lines and intersection thereof of the building target in the image, determining a straight line passing through the intersection and parallel to an azimuth, wherein the two included angles between the straight line and the two bright lines are azimuth angles; estimating the azimuth angle value; and estimating the image incident angle value according to the quantitative relation between the image incident angel and the azimuth angle. The SAR image incident reference value is estimated by utilizing two bright lines of the building target in the SAR slant-range image and the quantitative relation between the included angle formed by two bright lines and the azimuth and the image incident angle, the SAR image incident angle parameter is precisely estimated under the condition that information such as flying height of the sensor is in absent, the SAR image analysis, parameter inversion and information extraction process can be satisfied, the application level of the SAR image is improved, and the method is especially suitable for the emergency relief with high timeliness demand.

Description

technical field [0001] The invention relates to the technical field of SAR image incident angle estimation, in particular to a SAR image incident angle estimation method based on building target image features. Background technique [0002] Synthetic Aperture Radar (SAR) is oblique-range side-view imaging, which transmits and receives backscattered echo energy from ground objects, and ground objects in different distances correspond to different incident angles. When the same type of surface object is under different incident angles, its backscattering characteristics are different, that is, the SAR image features are related to the radar incident angle. In the process of SAR image analysis, parameter inversion and information extraction, the incident angle is an indispensable radar imaging parameter. Therefore, estimation of incident angle of SAR image is an important link in SAR data processing. The existing radar image incidence angle estimation method mainly estimates ...

AI Technical Summary

Problems solved by technology

[0005] However, when the acquired SAR image lacks information such as the altitude of the sensor, especially in emergency relief with extremely high timeliness requirements, the existing methods cannot estimate the incident angle of the radar image, thus limiting the application of the SAR image.

[0006] It can be seen that the above-mentioned existing SAR image incidence angle estimation method obviously still has deficiencies in use, and further improvement is urgently needed

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