40 results about "Permanent scatterer" patented technology

The invention discloses a time sequence processing method and device for a distributed target InSAR with enhanced space-time coherence. The method comprises the steps of carrying out threshold separation on a permanent scatterer (PS) and a distributed scatterer (DS) on the basis of an obtained single complex image data stack; performing phase stability analysis on separated PS candidate points bymeans of a StaMPS approach to obtain PS points; carrying out covariance matrix estimation on DS candidate points one by one through a maximum likelihood estimator and refining a covariance matrix through a bootstrapped coherence estimator; performing time sequence phase optimization on each DS candidate point; selecting DS points; constructing a two-layer network for the selected PS and DS points;carrying out phase error separation on an unwrapping phase after three-dimensional phase unwrapping is performed on the PS points and the DS points; utilizing the maximum likelihood estimator and a phase model to estimate geophysical parameters. The method can reduce the uncertainty of InSAR time sequence analysis caused by coherence loss and an ill-conditioned matrix, improve the quality controlof time sequence data processing and thus improve the estimation precision and reliability of products.

The invention relates to a deformation monitoring method of a foundation SAR in a time decorrelation serious area. The method comprises the specific steps of S1 permanent scatterer point selection, S2 triangular mesh generation, S3 space-time three-dimensional phase position untwisting, S4 atmosphere phase compensation, S5 deformation inversion and S6 isolated PS point corresponding deformation quantity removal. The step S1 comprises the specific step that amplitude deviation screening, amplitude threshold screening and phase information screening are conducted respectively. By the adoption of the method, based on a traditional PS point selection amplitude deviation method, amplitude threshold screening and phase information screening are added so that PS points with higher quality can be extracted, and therefore deformation monitoring has higher accuracy.

The invention discloses an atmospheric phase screen extraction method based on ground-based SAR (synthetic aperture radar) interference. Atmospheric phase is extracted according to a ground-based radar differential interferometric phase model on basis of a least squares fitting linear deformation and time-space filtering method. The ground-based radar differential interferometric phase model has a full consideration of the ground-based radar imaging mechanism and the differential interference theory so as to extract an atmospheric phase screen. A PS (permanent scatterer) point selection method of three levels, amplitude dispersion index, correlation index and phase stability, is provided, the atmospheric phase screen of radar data of each scene is finally obtained by means of Kriging interpolation, and accurate extraction of the phase generated under atmospheric interference has an important role on improving radar interferometric precision. Correctness of the method is verified by measured dam data, and the method is of certain actual application value and universality.

The invention relates to a multi-source remote sensing image-based urban area elevation dimension change information extraction method. The method comprises the following steps of 1, based on a PS-InSAR (permanent scatterer radar interferometry) technology, extracting earth's surface deformation information by a COSMO-SkyMed high-resolution ratio radar image, and acquiring surface elevation dimension whole-deformation quantity as elevation dimension change base quantity, 2, based on a stereo-image high-precision matching technology, by a source 3 stereo-image, extracting digital surface model (DSM) and acquiring different-time phase DSM data showing elevation changes of various ground objects distributed on the earth's surface, and 3, calculating the difference of the different-time phase DSM data, and subtracting a surface settlement value obtained by radar image processing to obtain real elevation change information of the various ground objects. The method provided by the invention can eliminate the influence produced by surface whole-deformation quantity on an elevation dimension change information detection result, and improves a detection precision.

The invention provides a transformer substation geological deformation monitoring method based on an SAR satellite and a Beidou satellite, and the method comprises the steps: selecting a main image in SAR satellite images, and carrying out the registration of the SAR satellite images based on the main image; performing differential interference processing on the registered SAR satellite image based on a time sequence to obtain a phase coherence graph; selecting permanent scatterer points based on pixels in the phase coherence graph, and generating an interference phase sequence according to the selected permanent scatterer points; analyzing the deformation condition of the permanent scatterer points according to the interferometric phase sequence to obtain a periodic monitoring result of the geological deformation of the transformer substation; and according to a periodic monitoring result, selecting an area which needs to be monitored emphatically, and carrying out real-time geological deformation monitoring on the area which needs to be monitored emphatically through a Beidou satellite settlement monitoring station. The SAR satellite and the Beidou satellite are combined to maximize the monitoring effect, and the geological deformation monitoring level and quality of the transformer substation in China are improved.

The invention discloses a high-speed railway settlement monitoring technology. A satellite time sequence differential radar interference technology is used for monitoring the settlement change of a high-speed railway. Natural permanent scatterers (PS) are matched with artificial corner reflectors (CR) to construct a mixed scatterer network; the satellite time sequence differential radar interference technology adopts satellite SAR images with multiple time phases, high resolution and short wavelength; and the mixed scatterer network is constructed by adopting a free connection method. The method of the invention can solve the problem of settlement monitoring in vegetation-covered areas or farmland areas where effective natural PS can not be easily obtained generally. The time sequence differential radar interference technology based on the mixed scatterer network can ensure the reliability and the accuracy of settlement monitoring of the high-speed railway. Fixed and split artificial corner reflectors are arranged simultaneously, thereby ensuring the success rate of settlement monitoring in vegetation-covered areas and farmland areas, saving the land area and reducing the monitoring cost of the artificial corner reflectors.

The invention discloses a bistatic/multistatic radar image PS (permanent scatterer) point associating method based on a sliding scattering center, which accurately registers multiple SAR images viewed from different angles, and belongs to the field of bistatic/multistatic synthetic aperture radars. The method comprises: obtaining an approximate target outline scattering function by performing parabolic fitting on a PS point target outline function in a bistatic image; obtaining a homonymy point in a monostatic radar image by performing moving window search on the monostatic radar image; and finally, registering the monostatic radar image according to the homonymy point obtained through the search. The method fully utilizes the characteristics of the sliding scattering PS point target, solves a puzzle that a conventional PS point registering method is just capable of accurately registering images observed from a single angle, and has significant meaning to multi-angle radar image fusion and interference processing.

The invention relates to a ground-based radar self-adaptive threshold permanent scatterer recognition method and device and a storage medium. The method comprises the following steps: performing grouping operation on acquired time sequence SAR (Synthetic Aperture Radar) images; obtaining a candidate permanent scatterer point set of each group of SAR images by using an amplitude threshold method; generating a coherence coefficient sequence based on the coherence coefficient of each pixel in the candidate permanent scatterer point set so as to obtain a high-coherence permanent scatterer class through a clustering algorithm; based on the amplitude deviation information and the phase stability information of each pixel in the high-coherence permanent scatterer class, respectively obtaining a corresponding low-amplitude deviation permanent scatterer class and a high-phase stability permanent scatterer class through a clustering algorithm; and identifying target permanent scatterer points based on the low-amplitude-deviation permanent scatterer class and the high-phase-stability permanent scatterer class. According to the embodiments of the invention, the stability of the number of the PS points can be greatly improved, the self-adaptive threshold PS point selection of the ground-based radar is realized, and a good foundation is laid for high-precision deformation inversion.

The invention discloses a method for expressing the evolution trend of a ground settlement space, comprising the following steps: a data set obtained through permanent scatterer interferometry and a data set obtained through small baseline interferometry are fused to acquire surface deformation information; a weighted standard deviation ellipse method is used to analyze the directionality of PS point distribution in the surface deformation information; and the weighted standard deviation ellipse of PS point spatial distribution is calculated by respectively taking the average settlement rate and the settlement of each year as the weight, wherein the standard deviations of geographical elements in the X direction and in the Y direction are respectively calculated by taking the average position of spatial distribution of the geographical elements in the surface deformation information as the ellipse center, the ellipse axes containing geographical element distribution are thus defined, the direction of the long axis of the ellipse reflects the main trend direction of distribution in a two-dimension space, and the direction of the short axis represents the degree of deviation from the center of gravity in the secondary direction.

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.

The invention discloses a high-frequency earthquake area converter station slope settlement monitoring method based on an InSAR technology. The method comprises the following steps: (1) a manual corner reflector is arranged on the slope or an anti-slide pile of the converter station, wherein the manual corner reflector is used as a permanent scatterer; (2) a synthetic aperture radar is used to transmit radar waves to the manual corner reflector; (3) a complex image pair of the same manual corner reflector is acquired; and (4) by using the phase difference of the complex image pair of the manual corner reflector, a microwave path difference in twice imaging is obtained, and small changes and settlement of the topography, the geomorphology and the surface of the manual corner reflector are then calculated. The manual corner reflector is used to avoid dense vegetation interference, the problem that a high slope area converter station permanent scatterer point is severely disturbed can be solved, and the small changes and the settlement of the slope and the anti-slide pile are obtained accurately.

The invention discloses a long sequence automatic interferometry system and method, including a storage, an instruction acquisition module, a data preparation module and an automatic processing module. The data preparation module includes a raw data acquisition module, a crawler module, a data format conversion module and a target area digital elevation model generation module. The automatic processing module includes a main image selection module, a registration resampling module, a permanent scatterer point extraction module, an optimal interference network generation module, an interferencefringe pattern generation module, a target interference fringes generation module and an analysis module. The long sequence automatic interferometry system and method can integrate differential interferometry and permanent scatterer processing, achieve the automatic processing of SAR data through standardized customization for a processing procedure, do not require manual intervention, do not require a complicated learning process when users use, are simple and convenient to operate and reduce threshold of the users. Meanwhile, the long sequence automatic interferometry system and method canachieve parallel computing of various phase analysis and achieve high efficiency in data processing.

The invention relates to a deformation rate estimation method and system, and the method comprises the steps: recognizing homogeneous pixels, and constructing a coherence matrix; performing eigenvalue decomposition and principal component analysis on the coherence matrix to obtain an optimized phase; calculating time coherence according to the interferometric phase with low noise and clear fringes; selecting a distributed scatterer according to a homogeneous pixel preset threshold value and a time coherence preset threshold value; and performing combined processing on the distributed scatterer and the permanent scatterer, and estimating the deformation rate of each measurement point. According to the embodiment of the invention, the coherence matrix is constructed according to the homogeneous pixels, so that the problem of deviation caused by the participation of heterogeneous pixels in matrix estimation can be avoided; compared with a covariance matrix, the coherence matrix can avoid the influence of back scattering power imbalance possibly existing in the image; the time coherence is calculated by adopting an interference phase with low noise and clear fringes, so that the influence of the low-quality interference phase can be avoided; and principal component analysis is performed after eigenvalue decomposition of the coherence matrix, so that the operation efficiency of phase optimization can be improved.

The invention discloses a PS-InSAR precise search method based on a maximum periodogram, and relates to the field of signal processing. Aiming at the indexes: the elevation of a satellite-borne SAR toa scene and deformation speed measurement precision, the invention proposes the PS-InSAR precise search method based on the maximum periodogram. The method mainly comprises three steps: 1, carrying out the phase filtering of a satellite-borne long-term sequence differential interference image, and screening out permanent scatterer pixels through the deviation amplitude criterion; 2, roughly estimating the elevations and deformation rate values of permanent scatterers based on the maximum periodogram criterion; 3, taking the result of the maximum periodogram rough estimation as an initial value, and performing the no-constraint precise searching of the elevation and deformation rate value based on the maximum time sequence correlation coefficient criterion.

The invention discloses a building elevation measurement method based on a PSInSAR technology. The method specifically comprises the steps of S1 based on data of multiple high-resolution SAR images ofa target city, generating an InSAR big database through a permanent scatterer synthetic aperture radar interferometry technology, and obtaining PS point three-dimensional space position information of the target city; S2 introducing a statistical theory and a signal estimation method, and performing spatial grading twice estimation based on three-dimensional spatial positions of all PS point datain a target range to obtain urban ground elevation; S3 introducing a building vector box, selecting PS points in each building, clustering the PS point elevations in the building, removing wrong points, and calculating the roof elevation ; and S4 obtaining the height of the building by subtracting the ground PS point elevation from the roof PS point elevation. Data acquisition is not limited by the airspace; related data can be obtained in a large range; the automation degree is high; and the elevation of the urban house building can be quickly estimated.

The invention provides a radiation calibration method based on a communication signal tower. The method comprises the steps of establishing a simplified model of the communication signal tower, namelymodeling the communication signal tower for obtaining a dihedral angle reflector and a cylindrical scatter; calculating the RCS of the communication signal tower of the dihedral angle reflector model; calculating the RCS of the communication signal tower of the cylindrical scatter model; calculating the RCS of a permanent scatter of the communication signal tower; calculating the target pulse response energy of each communication signal power by means of an integration method; and solving a radiation scaling constant K. According to the method of the invention, the communication signal toweris researched; the communication signal tower is used as one permanent scatter; model simplification is performed on the communication signal tower for calculating a signal tower model RCS; and furthermore the signal tower is used for performing radiation calibration. Correctness, feasibility and validity of the radiation calibration method are verified through simulation. A new effective approachis supplied for quantitative remote sensing in a global range.

The invention discloses a PS-InSAR phase unwrapping method based on time domain difference and a system and application thereof, and the method comprises the steps: obtaining an arc segment differential interferometric phase of a differential interferogram of a synthetic aperture radar image through the setting of a permanent scatterer point; dividing the winding number of the phase into phase winding caused by terrain residual difference and winding caused by deformation difference, solving the phase winding and the winding respectively so as to unwind the segmental arc phase, then obtaining estimated values of deformation rate difference and terrain residual difference through a least square method, and calculating the phase winding number of the segmental arc phase through a net adjustment method. And direct calculation of the deformation rate, the terrain residual error and the deformation time sequence of the permanent scatterer point is realized. According to the method, the problems of low unwrapping efficiency, serious resolving time consumption, insufficient nonlinear deformation recovery and low precision when PS-InSAR is used for large-range deformation monitoring under mass data can be effectively solved, and high-precision rapid resolving of parameters and direct recovery of a deformation sequence are realized.