A ps-insar exact search method based on maximum periodogram

Abstract

The invention discloses a PS-InSAR accurate search method based on the maximum periodogram, relates to the field of signal processing, and proposes a PS-InSAR accurate search method based on the maximum periodogram for the index of the measurement accuracy of the scene elevation and deformation rate by the spaceborne SAR. search method. The method mainly includes three steps. Step 1: Perform phase filtering on the space-borne long-term differential interferometric images, and use the deviation amplitude criterion to screen out the permanent scatterer pixels; Step 2: Roughly estimate the permanent scatterer pixels based on the maximum periodogram criterion Elevation and deformation rate values; Step 3: Using the rough estimate of the maximum periodogram as the initial value, use the unconstrained and precise search for the elevation and deformation rate values ​​based on the maximum time series correlation coefficient criterion.

Description

Technical field [0001] The present invention belongs to the field of signal processing, and more particularly to a PS-INSAR precise search method based on the maximum periodic graph. Background technique [0002] Synthetic aperture radar interference measurement technology (INSAR) is a very developing surface-shaped variable detection technology, and has the advantages of synthetic aperture radar technology and interference measurement technology. It can achieve all-day work, with strong penetration capacity and 3D information and deformation information of the ground target can be measured in large, high precision. However, InSAR technology is very sensitive to factors such as atmospheric error, remote sensing satellite orbital, surface conditions, and time and space. Therefore, 1999 Italian Scholars Ferrettit and Rocca proposed permanent scattering body, which exerts both spatial loss and time loss correlation, because there is a lot of SAR data available, and atmospheric error...

AI Technical Summary

Problems solved by technology

The unconstrained search method based on the maximum time series correlation coefficient is to use the principle of the quasi-Newton method to find the optimal value of the objective function. This method has a small amount of calculation and a fast convergence speed, but it is not stable enough and is greatly affected by the setting of the initial value. Large; the maximum periodogram method is to perform spectral transformation on complex signals, transform from t-b space to h-v space, and find the corresponding value at the peak of the spectrum as the optimal value. It does not need to set the initial value, and the estimation accuracy is high and robust better performance, but the phase noise has a greater impact on the estimation results

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