A ground-based SAR atmospheric interference phase correction method and device

Abstract

The invention provides a correction method and apparatus for an atmospheric interference phase in a ground-based SAR. The method comprises S1, a ground-based SAR differential interferometer phase model is established; S2, filtering processing is carried out on the ground-based SAR differential interferometer phase model to filter a noise phase; S3, a high and permanent scattering body is screened from the ground-based SAR differential interferometer phase model with the filtered noise phase, wherein the high and permanent scattering body is a stable control point with a deformation phase being zero; S4, bidirectional curve fitting operation is carried out on the screened high and permanent scattering body to obtain a complete atmospheric interference phase, wherein the bidirectional curve fitting includes distance-to-curve fitting and direction-to-curve fitting; and S5, a deformation phase is obtained according to the ground-based SAR differential interferometer phase model obtained by the S1 and the atmospheric interference phase obtained by the S4. According to the invention, space-variant atmospheric interference phase correction is carried out by relying on the interferometer phase without the need to introduce any external auxiliary data; and the correction precision is high.

Description

technical field [0001] The invention relates to the field of ground-based SAR interferometry, in particular to a ground-based SAR atmospheric interference phase correction method and device. Background technique [0002] Atmospheric interference is caused by the different phase delays caused by the atmospheric pressure, temperature, and humidity changing in time and space due to the radar electromagnetic wave signal passing through the atmosphere during propagation. Atmospheric interference seriously affects the accuracy and reliability of radar interferometry deformation inversion, and has always been one of the important factors hindering the development of InSAR interferometry applications. The existing InSAR atmospheric interference phase correction methods are mainly divided into two categories: (1) based on external auxiliary data and (2) based on the interferometric phase itself. Methods based on external auxiliary data mainly include modeling based on surface meteor...

AI Technical Summary

Problems solved by technology

[0006] The existing ground-based SAR atmospheric interference phase correction algorithms mainly include interferometric phase filtering method, correction method based on time series SAR images, correction method based on external auxiliary data and atmospheric interference phase correction method based on stable control points, in which the interferometric phase filtering method , The correction method based on time series SAR images faces the problem of separating the atmospheric interference phase and nonlinear deformation. The phase correction method based on external auxiliary data is mainly affected by the low spatial resolution of auxiliary data, and the correction effect is often not very ideal

However, the existing atmospheric disturbance phase correction algorithm based on stable control points is proposed under the assumption that the atmospheric phase delay is consistent in azimuth, and there is a problem of under-correction of the atmospheric disturbance phase azimuth.

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