An interferometric calibration method for airborne polarization interferometric synthetic aperture radar images

Abstract

The invention relates to an interferometric calibration method for airborne polarization interferometric synthetic aperture radar image. The method is designed for obtaining the polarization interference airborne synthetic aperture radar images, and comprises: 1) obtaining an interferometric synthetic aperture radar image and collecting ground control point 3d coordinate; 2) generating four interferograms of polarization modes; selecting one interferogram of polarization mode and realizing the polarization interference relative calibration of the interference graph of the other three polarization modes; 3) carrying out the interference graph of the polarization mode of the benchmark and the other polarization modes of the relative calibration in phase; 4) based on airborne SAR strict geometric model, constructing the absolute calibration error equation; making use of the ground control points to solve the polarization interference airborne synthetic aperture radar image geometric parameters and benchmark solution bound interference figure wrapped phase correction vector composed of the corresponding solution; 5) the polarization interference of the airborne polarization interference synthetic aperture radar image including geometric parameter correction and absolute phase correction is absolutely definite. Described method can improve the existing airborne synthetic aperture radar polarization interference measurement accuracy, provide solutions in the application of airborne double / full polarization interferometric synthetic aperture radar system for surface 3 d reconstruction and extract object height play an important role, has a better technical effect.

Description

Technical field [0001] The invention belongs to the field of digital photogrammetry for remote sensing images, and particularly relates to an interference calibration method for airborne polarization interference synthetic aperture radar images. Background technique [0002] Polarimetric Interferometric Synthetic Aperture Radar (PolInSAR) as an active microwave remote sensing technology has shown more and more advantages in terrain mapping. The phase information of synthetic aperture radar (Synthetic Aperture Radar, SAR) images is a key step in extracting high-precision terrain and altitude information. Polarization Interferometric Synthetic Aperture Radar further improves the measurement accuracy of terrain and altitude by combining SAR images with multiple polarization methods. . For airborne polarized interferometric synthetic aperture radar sensors, the acquired images are extremely susceptible to error sources such as asynchronous transmission or reception of the polarizati...

AI Technical Summary

Problems solved by technology

This method does not correct the geometric parameters, so the prerequisite for the realization of this method is that the airborne platform is stable and there is no error in the geometric parameters.

(2) Another type of method selects the electromagnetic wave front as a plane and constructs a simplified geometric model by assuming that the ground is flat. The accuracy of estimating geometric parameters such as the baseline is low, which directly affects the subsequent measurement accuracy of terrain and height.

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