CN112197691A - InSAR (interferometric synthetic Aperture Radar) measuring method and device based on temporary coherent scatterer and storage medium - Google Patents

Abstract

An InSAR measuring method and device based on a temporary coherent scatterer and a storage medium are provided, wherein a coherent phase matrix is obtained by performing interference processing on every two SAR images in an SAR image sequence, temporary coherent pixel points in the SAR images are identified based on the coherent phase matrix, and phase unwrapping is performed on the identified temporary coherent pixel points to obtain a deformation sequence of the temporary coherent pixel points, so that the deformation of the temporary coherent pixel points is monitored, and an InSAR measuring result of the temporary coherent scatterer is obtained.

Description

InSAR measurement method and device and storage medium based on temporary coherent scatterers

technical field

The invention relates to the technical field of InSAR, in particular to an InSAR measurement method and device based on a temporary coherent scatterer, and a storage medium.

Background technique

China's mountainous and hilly areas account for about 65% of the country's land area, with complex geological conditions, frequent tectonic activities, and sudden geological disasters such as collapses, landslides, and debris flows. one of the most numerous countries. At present, nearly 300,000 hidden geological disasters have been found nationwide, threatening the lives of about 20 million people and the safety of property worth 450 billion yuan. How to discover and effectively identify the potential hidden dangers of major geological disasters in advance and actively prevent and control them has become the focus and difficulty of the recent geological disaster prevention and control field. The settlement of the reclamation area also threatens the safety and stability of buildings, public facilities and other buildings.

Among them, the measurement of deformation in geological regions is the core technology for early discovery and effective identification of major geological disasters. Commonly used deformation measurement methods include total station observation method, leveling subsidence observation method, etc. These measurement methods usually require on-site measurement marks. , Regular manual on-site operation requires a lot of manpower and material resources, including the currently mature BeiDou/GNSS observation technology that also requires on-site deployment, and the price is relatively expensive.

Due to its advantages of large-scale, high-precision, and all-weather measurement, InSAR technology has gradually matured and been used in urban land subsidence observation, landslide deformation monitoring and other fields. However, the vegetation growth or deformation gradient on the landslide surface is too large, and the construction on the surface of the reclamation area can cause the InSAR interferogram to appear decoherent in a certain period of time. Existing interferometry techniques for permanent scatterers and identically distributed scatterers mainly use pixel points whose coherence remains high during the entire observation period or whose coherence remains high and remains continuous during a short observation period. Scatterers that maintain coherence over a period of time cannot obtain valid monitoring results.

SUMMARY OF THE INVENTION

The technical problem mainly solved by the present invention is how to obtain the InSAR measurement result of the temporary coherent scatterer.

According to a first aspect, an embodiment provides an InSAR measurement method based on a temporary coherent scatterer, including:

acquiring a SAR image sequence of the area to be monitored, the SAR image sequence including multi-scene SAR images of continuous monitoring time;

Interferometric processing is performed on every two SAR images in the SAR image sequence to obtain multiple interferograms;

determining temporary coherent pixels and permanent coherent pixels in the SAR image according to the plurality of said interferograms;

performing phase unwrapping on the determined temporary coherent pixel points to obtain a phase unwrapping sequence of the temporary coherent pixel points;

converting the phase unwrapped sequence into a deformed sequence of the temporary coherent pixels;

Based on the deformation sequence of the temporary coherent pixel points, the cumulative deformation sequence of the temporary coherent pixel points is obtained by fitting, and the cumulative deformation sequence of the temporary coherent pixel points is used to monitor the cumulative deformation amount of the temporary coherent pixel points.

According to a second aspect, an embodiment provides an InSAR measurement device based on a temporary coherent scatterer, including:

an acquisition module, configured to acquire a SAR image sequence of the area to be monitored, where the SAR image sequence includes multi-scene SAR images of continuous monitoring time;

The interferometric processing module is used for interferometric processing of every two SAR images in the SAR image sequence to obtain multiple interferograms;

a temporary coherent pixel point extraction module, used for determining temporary coherent pixel points and permanent coherent pixel points in the SAR image according to a plurality of the interferograms;

a phase unwrapping module, configured to perform phase unwrapping on the determined temporary coherent pixels to obtain a phase unwrapping sequence of the temporary coherent pixels;

a deformation sequence determination module, configured to convert the phase unwrapping sequence into a deformation sequence of the temporary coherent pixel points;

A cumulative deformation sequence determination module, configured to obtain the cumulative deformation sequence of the temporary coherent pixel points by fitting based on the deformation sequence of the temporary coherent pixel points, and the cumulative deformation sequence of the temporary coherent pixel points is used to monitor the temporary coherent pixel points The cumulative deformation of the point.

According to a third aspect, an embodiment provides a computer-readable storage medium, comprising a program that can be executed by a processor to implement the method described in the above embodiment.

According to the InSAR measurement method and device based on temporary coherent scatterers in the above embodiments, by performing interference processing on every two SAR images in the SAR image sequence, a coherent phase matrix is obtained, and the temporary coherent pixel points in the SAR image are determined based on the coherent phase matrix. Perform identification and phase unwrapping of the identified temporary coherent pixels to obtain the deformation sequence of the temporary coherent pixels, so as to monitor the deformation of the temporary coherent pixels to obtain the InSAR measurement results of the temporary coherent scatterers.

Description of drawings

1 is a flowchart of an InSAR measurement method based on a temporary coherent scatterer according to an embodiment;

2 is a schematic structural diagram of an InSAR measurement device based on a temporary coherent scatterer according to an embodiment;

Fig. 3 is the InSAR measurement result figure that adopts the existing method;

FIG. 4 is an InSAR measurement result diagram using an embodiment of the present invention.

Detailed ways

The present invention will be further described in detail below through specific embodiments in conjunction with the accompanying drawings. Wherein similar elements in different embodiments have used associated similar element numbers. In the following embodiments, many details are described so that the present application can be better understood. However, those skilled in the art will readily recognize that some of the features may be omitted under different circumstances, or may be replaced by other elements, materials, and methods. In some cases, some operations related to the present application are not shown or described in the specification, in order to avoid the core part of the present application from being overwhelmed by excessive description, and for those skilled in the art, these are described in detail. The relevant operations are not necessary, and they can fully understand the relevant operations according to the descriptions in the specification and general technical knowledge in the field.

Additionally, the features, acts, or characteristics described in the specification may be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can also be exchanged or adjusted in order in a manner obvious to those skilled in the art. Therefore, the various sequences in the specification and drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a required order unless otherwise stated, a certain order must be followed.

The serial numbers themselves, such as "first", "second", etc., for the components herein are only used to distinguish the described objects, and do not have any order or technical meaning. The "connection" and "connection" mentioned in this application, unless otherwise specified, include both direct and indirect connections (connections).

Please refer to FIG. 1 . FIG. 1 is a flowchart of an InSAR measurement method based on a temporary coherent scatterer according to an embodiment, which includes steps S10 to S50 , which will be described in detail below.

In step S10, a SAR image sequence of the area to be monitored is acquired, wherein the SAR image sequence includes multi-scene SAR images of continuous monitoring time.

Step S20: Interferometric processing is performed on every two SAR images in the SAR image sequence to obtain a plurality of interferograms.

Step S30: Determine temporary coherent pixels and permanent coherent pixels in the SAR image according to the plurality of interferograms.

Step S40, performing phase unwrapping on the determined temporary coherent pixel points to obtain a phase unwrapping sequence of the temporary coherent pixel points.

Step S50 , converting the phase unwrapping sequence into the deformation sequence of the temporary coherent pixel points, wherein the deformation sequence of the temporary coherent pixel points is used to represent the deformation of the temporary coherent pixel points in the SAR image.

Step S60 , based on the deformation sequence of the temporary coherent pixel points, obtain the cumulative deformation sequence of the temporary coherent pixel point by fitting, wherein the cumulative deformation sequence of the temporary coherent pixel point is used to monitor the cumulative deformation amount of the temporary coherent pixel point.

In this embodiment, it is assumed that the SAR image sequence of the area to be monitored includes SAR images with continuous monitoring time of N scenes, and the InSAR interferogram sequence is obtained by performing interferometric processing on every two SAR images in the N scene SAR images, that is, the N*(N-1)/2 interferograms. Moreover, all the SAR images in the SAR image sequence are captured images of the same area and have the same pixel points.

According to the N*(N-1)/2 interferogram obtained above, determine the temporary coherent pixels and permanent coherent pixels in the SAR image, including:

Determine the interference phase and coherence coefficient for each coherent pixel in the interferogram.

According to the interference phase and coherence coefficient of each coherent pixel point, a coherent phase matrix C corresponding to each coherent pixel point is formed, wherein the coherent phase matrix C

表示SAR影像p和SAR影像q的相干系数，φ_pq为SAR影像p和SAR影像q的干涉相位。Among them, p and q are the serial numbers of SAR images, and p and q are 1, 2...N,

represents the coherence coefficient of SAR image p and SAR image q, and φ _pq is the interference phase of SAR image p and SAR image q.

In other words, all pixels in the SAR image sequence can obtain a coherent phase matrix after interference processing, that is, each pixel corresponds to a coherent phase matrix.

Do the following traversal over all coherent pixels in the interferogram:

If the coherent phase matrix C corresponding to the current coherent pixel point has an invalid interference phase within a part of the monitoring time, the current coherent pixel point is a temporary coherent pixel point;

Wherein, if there is a coherence coefficient smaller than the set threshold, the interference phase is an invalid interference phase; otherwise, the interference phase is an effective interference phase. Remove the invalid interference phase and coherence coefficient from the coherence phase matrix C, and then realize the judgment of the effective monitoring period after removing the invalid interference phase through connectivity judgment. The connectivity judgment can use DFS, BFS, Tarian and other undirected connected graph judgment methods . In this embodiment, in order to increase the reliability of the effective monitoring time period identification, it is required that the number of valid observation values in the effective monitoring time period is greater than the number of SAR images in the time period, and the number of SAR images is greater than or equal to 3, that is, the corresponding sub-coherence phase matrix is obtained. Cs; otherwise, the interference phase within the monitoring period is an invalid interference phase.

Among them, s is the serial number of the sub-monitoring time period, and the value is [1, S]. Assuming that the m-th to n-th scene images are the acquired sub-monitoring time period, the coherent phase matrix of the sub-monitoring time period

If the coherent phase matrix corresponding to the current coherent pixel point has an effective interference phase in any monitoring time period, the current coherent pixel point is a permanent coherent pixel point.

In one embodiment, phase unwrapping is performed on the determined temporary coherent pixels to obtain a phase unwrapping sequence of the temporary coherent pixels, including:

The following traversal is performed on the temporary coherent pixels:

The phase sequence difference between the current temporary coherent pixel point and the pre-acquired reference pixel point is calculated to obtain the arc segment phase sequence.

Specifically, it includes: selecting permanent scatterer pixels or coherent coherent pixels around the current temporary coherent pixel as pre-acquired reference pixels. In this embodiment, the reference pixels are selected based on a double threshold of spatial distance and the quality of the reference pixels, and the quality of the reference pixels is mainly the amplitude dispersion value of the permanent scatterer pixels or the coherence coefficient of the identically distributed target points.

Calculate the phase sequence difference between the current temporary coherent pixel point and the pre-acquired reference pixel point by the following formula:

表示当前临时相干像素点i与参考像素点j在第k个监测时间之间的相位序列差值，

表示参考像素点j在第k个观测时间对应的干涉相位，

表示当前临时相干像素点i在第k个观测时间对应的干涉相位；其中，第k个观测时间表示SAR影像序列中第k景SAR影像。in,

represents the phase sequence difference between the current temporary coherent pixel point i and the reference pixel point j at the kth monitoring time,

represents the interference phase corresponding to the reference pixel j at the kth observation time,

represents the interference phase corresponding to the current temporary coherent pixel point i at the kth observation time; where the kth observation time represents the kth scene SAR image in the SAR image sequence.

The phase unwrapping in the time domain is performed on the arc phase sequence, and the unwrapped arc timing phase is obtained.

Specifically, it includes: estimating the elevation error difference ΔE _j and the linear deformation rate difference Δv _j corresponding to the arc phase sequence.

和线性变形速率差值的估计值

如果系数γ超过了设定的阈值，则认为该弧段有效。时间相干系数可表示为:In this embodiment, the temporal coherence coefficient is used as the quality standard for selecting effective arc segments, and the estimated value of the corresponding elevation error difference can be calculated by maximizing the temporal and temporal coherence coefficient γ

and an estimate of the difference between the linear deformation rates

If the coefficient γ exceeds the set threshold, the arc is considered valid. The time coherence coefficient can be expressed as:

为地形误差相位，

为线性变形速率差值对应的相位值，λ为雷达卫星电磁波波长，R为雷达卫星到目标点的距离，θ为电磁波入射角，

为干涉图垂直基线长度，T^sk为干涉图的时间间隔。in,

is the terrain error phase,

is the phase value corresponding to the linear deformation rate difference, λ is the wavelength of the radar satellite electromagnetic wave, R is the distance from the radar satellite to the target point, θ is the incident angle of the electromagnetic wave,

is the vertical baseline length of the interferogram, and T ^sk is the time interval of the interferogram.

和线性变形速率

其中，参考像素点的高程误差和变形速率等参数通过现有方法计算获得。Add the estimated elevation error difference and linear deformation rate difference corresponding to the arc phase sequence with the pre-acquired elevation error and deformation rate of the reference pixel point to obtain the elevation error of the current temporary coherent pixel point

and linear deformation rate

Among them, parameters such as the elevation error and deformation rate of the reference pixel are calculated and obtained by existing methods.

If the number of valid arc segments is multiple, multiple elevation errors and linear deformation rates corresponding to the current temporary coherent pixels can be obtained. In this embodiment, the median method is used to obtain the elevation error and the linear deformation rate corresponding to the current temporary coherent pixel point.

和线性变形速率

可表示为：Assuming that the number of valid arcs corresponding to the current temporary coherent pixels is H, the elevation error of the current temporary coherent pixels

and linear deformation rate

can be expressed as:

和弧段线性变形速率

The elevation error and linear deformation rate of the current temporary coherent pixel point are subtracted from the elevation error and deformation rate of the pre-acquired reference pixel point to obtain the arc elevation error

and arc segment linear deformation rate

The phase corresponding to the arc elevation error and the arc linear deformation rate is removed from the arc phase sequence to obtain the residual arc timing phase.

主要为相位噪声、大气相位残余项等，可认为其小于π。最终可获得解缠后的弧段时序相位可表示为：In this embodiment, the phase corresponding to the arc segment elevation error and the arc segment linear deformation rate is removed from the arc segment phase sequence, and the obtained residual arc segment timing phase

It is mainly the phase noise, atmospheric phase residual term, etc., which can be considered to be less than π. Finally, the unwrapped arc segment timing phase can be expressed as:

表示弧段高程误差

对应的相位，

表示弧段线性变形速率

对应的相位。in,

Indicates the arc elevation error

corresponding phase,

Indicates the linear deformation rate of the arc segment

corresponding phase.

In one embodiment, the phase unwrapping in the space domain is performed on the unwrapped arc segment timing phase to obtain the phase unwrapping sequence of the current temporary coherent pixels, further comprising:

If the number of pre-acquired reference pixels is multiple, then multiple phase unwrapping sequences corresponding to the current temporary coherent pixels can be obtained; in this embodiment, based on the pre-acquired multiple reference pixels, H temporary coherent pixels can be obtained The phase unwrapping sequence corresponding to the point.

If the H phase unwrapping sequences are all equal, the current temporary coherent pixel point is a credible monitoring point;

If the H phase unwrapping sequences are partially equal, and the number of equal phase unwrapping sequences is greater than the number of unequal phase unwrapping sequences, the current temporary coherent pixel point is a credible monitoring point;

Otherwise, the current temporary coherent pixel is an unreliable monitoring point.

In this embodiment, the unwrapped phase sequence of the credible monitoring point can be converted into a deformation sequence d according to the wavelength of the incident wave of the radar satellite.

Due to the discontinuity of the deformation sequence corresponding to the temporary coherent pixels, the deformation amount cannot be transferred between the temporary coherent time periods, resulting in the inability to obtain the accumulated deformation amount.

In this embodiment, the deformation sequence difference Δd (arc segment deformation sequence) between the temporary coherent pixel point and the nearest surrounding reference pixel point is calculated first, and then linear or exponential function fitting is performed on the arc segment deformation sequence in the first effective monitoring period. , which computes the function polynomial coefficients. For landslide body monitoring, the present invention adopts a linear function fitting method. For the settlement monitoring of the reclamation area, according to the consolidation characteristics of the soft soil, the present invention adopts an exponential function fitting method. According to the above fitting polynomial, the deformation amount at the start time of the second effective monitoring period is predicted. Then, fit and predict sequentially. Finally, the cumulative deformation sequence of arc segments is obtained. The cumulative deformation sequence corresponding to the temporary coherent pixels can be obtained by adding the cumulative deformation sequence of the arc segment to the deformation sequence of the nearest reference point around it. According to its cumulative deformation sequence, the cumulative variables of temporary coherent pixels can be observed.

Please refer to FIG. 2 , which is a schematic structural diagram of an InSAR measurement device based on a temporary coherent scatterer according to an embodiment, including: an acquisition module 10 , an interference processing module 20 , a temporary coherent pixel point extraction module 30 , and a phase unwrapping module 40 , a deformation sequence determination module 50 and a cumulative deformation sequence determination module 60 .

Wherein, the acquisition module 10 is used to acquire a SAR image sequence of the area to be monitored, and the SAR image sequence includes multi-scene SAR images of continuous monitoring time.

The interferometric processing module 20 is used for interferometric processing on every two scene SAR images in the SAR image sequence to obtain multiple interferograms.

The temporary coherent pixel point extraction module 30 is configured to determine temporary coherent pixel points and permanent coherent pixel points in the SAR image according to the plurality of said interferograms.

The phase unwrapping module 40 is configured to perform phase unwrapping on the determined temporary coherent pixels to obtain a phase unwrapping sequence of the temporary coherent pixels.

The deformation sequence determination module 50 is configured to convert the phase unwrapping sequence into the deformation sequence of the temporary coherent pixel points, and the deformation sequence of the temporary coherent pixel points is used to represent the deformation of the temporary coherent pixel points in the SAR image.

The cumulative deformation sequence determination module 60 is configured to obtain the cumulative deformation sequence of the temporary coherent pixel points by fitting based on the deformation sequence of the temporary coherent pixel points, wherein the cumulative deformation sequence of the temporary coherent pixel points is used to monitor the temporary coherent pixel points. cumulative deformation.

It should be noted that the device modules in this embodiment correspond to the method steps of the foregoing embodiments, and the specific implementations thereof have been specifically described in the foregoing embodiments, and will not be repeated here.

In this example, a landslide is used as an example to conduct experiments. After data analysis and investigation, it is found that the deformation of the slope continues to develop after the reservoir is impounded, and it shows an increasing trend with time. The Sentinel-1 image data is used as the test data, the spatial resolution of the image is 20m in azimuth direction × 5m in distance direction, the operating band is C-band, and the image shooting time range is from March 8, 2018 to July 1, 2019. Image collection The frequency is 1 scene every 12 days.

First, the traditional time-series InSAR analysis method was used to obtain the deformation monitoring results of the Guobu slope surface, as shown in Figure 3. The types of monitoring points extracted include permanent scatterers and identically distributed target scatterers. Analysis of the monitoring results shows that based on the Sentinel-1 satellite image, a certain number of deformation monitoring points can be obtained on the surface of the Guobu slope, and the deformation rate of the surrounding monitoring points is relatively large, the maximum deformation rate is -282.2mm/yr, which is located at the top of the slope. Location. The analysis shows that the interferogram is decoherent due to the excessive deformation rate in the middle part of the Guobu slope, and it is impossible to obtain effective deformation monitoring points.

In this embodiment, the temporary coherent scatterer interferometry technique is used to process the data of the Sentinel-1 satellite image to obtain the deformation monitoring result of the landslide body. As shown in Fig. 4, Fig. 4 shows the deformation rate of monitoring points obtained by the InSAR measurement method of temporary coherent pixel points. Compared with the traditional data processing result in FIG. 3 , in the embodiment of the present invention, more monitoring points can be obtained in the middle part with a large slope deformation rate, and the number of monitoring points on the slope body surface can be increased by 323%. The deformation rate of the monitoring point on the slope surface is relatively large, and the maximum deformation rate is -372.2 mm/yr, which is located in the middle of the slope. It can be seen from the analysis that, for the areas where the deformation rate is too large and decoherence occurs, the embodiment of the present invention can obtain more effective monitoring points, which is helpful for the identification of hidden danger points of rapidly deforming slopes.

Those skilled in the art can understand that all or part of the functions of the various methods in the foregoing embodiments may be implemented by means of hardware or by means of computer programs. When all or part of the functions in the above-mentioned embodiments are implemented by means of a computer program, the program may be stored in a computer-readable storage medium, and the storage medium may include: read-only memory, random access memory, magnetic disk, optical disk, hard disk, etc. The computer executes the program to realize the above-mentioned functions. For example, the program is stored in the memory of the device, and when the program in the memory is executed by the processor, all or part of the above functions can be realized. In addition, when all or part of the functions in the above-mentioned embodiments are implemented by a computer program, the program can also be stored in a server, another computer, a magnetic disk, an optical disk, a flash disk or a mobile hard disk and other storage media, and saved by downloading or copying All or part of the functions in the above embodiments can be implemented when the program in the memory is executed by the processor.

The above specific examples are used to illustrate the present invention, which are only used to help understand the present invention, and are not intended to limit the present invention. For those skilled in the art to which the present invention pertains, according to the idea of the present invention, several simple deductions, modifications or substitutions can also be made.

Claims (10)

1. An InSAR measurement method based on a temporary coherent scatterer is characterized by comprising the following steps:

acquiring an SAR image sequence of a region to be monitored, wherein the SAR image sequence comprises a multi-scene SAR image of continuous monitoring time;

performing interference processing on every two SAR images in the SAR image sequence to obtain a plurality of interferograms;

determining temporary coherent pixel points and permanent coherent pixel points in the SAR image according to the interferograms;

performing phase unwrapping on the determined temporary coherent pixel points to obtain a phase unwrapping sequence of the temporary coherent pixel points;

converting the phase unwrapping sequence into a deformed sequence of the temporary coherent pixel points;

and fitting to obtain an accumulated deformation sequence of the temporary coherent pixel points based on the deformation sequence of the temporary coherent pixel points, wherein the accumulated deformation sequence of the temporary coherent pixel points is used for monitoring the accumulated deformation of the temporary coherent pixel points.

2. The InSAR measurement method based on a temporary coherent scatterer according to claim 1, wherein after the phase unwrapping is performed on the determined temporary coherent pixel points, before the phase unwrapped sequence is converted into a deformed sequence of the temporary coherent pixel points, further comprising:

judging whether the temporary coherent pixel points are credible monitoring points or not based on the phase unwrapping sequence of the temporary coherent pixel points, and outputting a judgment result;

and if the judgment result is a credible monitoring point, converting the phase unwrapping sequence of the temporary coherent pixel point into a deformed sequence of the temporary coherent pixel point.

3. The InSAR measurement method based on a temporary coherent scatterer according to claim 1, wherein the determining temporary coherent pixel points and permanent coherent pixel points in an SAR image according to the plurality of interferograms comprises:

determining an interference phase and a coherence coefficient of each coherent pixel point in the interference pattern;

forming a coherent phase matrix corresponding to each coherent pixel point according to the interference phase and the coherent coefficient of each coherent pixel point;

and traversing all coherent pixel points in the interferogram as follows:

if the interference phase of a part of monitoring time period in the coherent phase matrix corresponding to the current coherent pixel point is invalid, the current coherent pixel point is a temporary coherent pixel point;

otherwise, the current coherent pixel point is a permanent coherent pixel point.

4. The InSAR measurement method based on a temporary coherent scatterer according to claim 3, wherein if the interference phase of a part of the monitoring time period in the coherent phase matrix corresponding to the current coherent pixel point is invalid, the method comprises:

determining the interference phase invalidity of the partial monitoring period by:

and if the coherence coefficient is smaller than a set threshold value, the interference phase corresponding to the monitoring time period is an invalid interference phase.

5. The InSAR measurement method based on a temporary coherent scatterer according to claim 2, wherein the phase unwrapping is performed on the determined temporary coherent pixel points to obtain a phase unwrapped sequence of the temporary coherent pixel points, and the method comprises:

and traversing the temporary coherent pixel points as follows:

calculating a phase sequence difference value of the current temporary coherent pixel point and a pre-acquired reference pixel point to obtain an arc segment phase sequence;

performing phase unwrapping of a time domain on the arc segment phase sequence to obtain an unwrapped arc segment time sequence phase;

and carrying out phase unwrapping of a spatial domain on the unwrapped arc segment time sequence phase to obtain a phase unwrapping sequence of the current temporary coherent pixel point.

6. The InSAR measurement method based on the temporary coherent scatterer as claimed in claim 5, wherein the calculating the phase sequence difference between the current temporary coherent pixel and the peripheral permanent coherent pixel comprises:

selecting permanent scatterer pixel points or identically distributed coherent pixel points around the current temporary coherent pixel point as pre-acquired reference pixel points;

calculating the phase sequence difference value of the current temporary coherent pixel point and the pre-acquired reference pixel point by the following formula:

wherein,

representing the phase sequence difference value between the current temporary coherent pixel point i and the reference pixel point j at the k observation time,

representing the interference phase corresponding to the reference pixel point j at the k-th observation time,

representing the interference phase corresponding to the current temporary coherent pixel point i at the k observation time; and the kth observation time represents the kth SAR image in the SAR image sequence.

7. The InSAR measurement method based on a temporary coherent scatterer according to claim 5, wherein the phase unwrapping of the arc phase sequence in the time domain to obtain the unwrapped arc time sequence phase comprises:

estimating an elevation error difference value and a linear deformation rate difference value corresponding to the arc phase sequence;

adding the estimated corresponding elevation error difference and linear deformation rate difference of the arc phase sequence with the previously acquired elevation error and deformation rate of the reference pixel point to obtain the elevation error and linear deformation rate of the current temporary coherent pixel point;

if the number of the effective arc sections is multiple, obtaining multiple elevation errors and linear deformation rates corresponding to the current temporary coherent pixel point;

subtracting the elevation error and the linear deformation rate of the current temporary coherent pixel point from the elevation error and the deformation rate of a pre-acquired reference pixel point to obtain an arc section elevation error and an arc section linear deformation rate;

removing phases corresponding to the arc section elevation error and the arc section linear deformation rate from the arc section phase sequence to obtain a residual arc section time sequence phase;

adding the phase corresponding to the arc section elevation error and the arc section linear deformation rate with the residual arc section time sequence phase to obtain the arc section time sequence phase after unwrapping;

and adding the phase of the arc segment time sequence after the unwrapping with the phase unwrapping sequence of the reference pixel point obtained in advance to obtain the phase unwrapping sequence of the temporary coherent pixel point.

8. The InSAR measurement method based on a temporary coherent scatterer according to claim 5, wherein the phase unwrapping of the spatial domain is performed on the unwrapped arc segment time sequence phase to obtain the phase unwrapped sequence of the current temporary coherent pixel point, further comprising:

if the number of the pre-acquired reference pixel points is multiple, multiple phase unwrapping sequences corresponding to the current temporary coherent pixel point can be obtained;

if the phase unwrapping sequences are all equal, the current temporary coherent pixel point is a credible monitoring point;

if the plurality of phase unwrapping sequences are partially equal and the number of the equal phase unwrapping sequences is greater than the number of the unequal phase unwrapping sequences, the current temporary coherent pixel point is a trusted monitoring point;

otherwise, the current temporary coherent pixel point is an untrusted monitoring point.

9. An InSAR measurement device based on a temporary coherent scatterer, comprising:

the SAR image sequence comprises a multi-scene SAR image of continuous monitoring time;

the interference processing module is used for carrying out interference processing on every two SAR images in the SAR image sequence to obtain a plurality of interference patterns;

the temporary coherent pixel extraction module is used for determining temporary coherent pixels and permanent coherent pixels in the SAR image according to the interferograms;

the phase unwrapping module is used for unwrapping the phase of the determined temporary coherent pixel points to obtain a phase unwrapping sequence of the temporary coherent pixel points;

a deformed sequence determining module, configured to convert the phase unwrapping sequence into a deformed sequence of the temporal coherent pixel;

and the accumulative deformation sequence determining module is used for fitting and obtaining the accumulative deformation sequence of the temporary coherent pixel points based on the deformation sequence of the temporary coherent pixel points, and the accumulative deformation sequence of the temporary coherent pixel points is used for monitoring the accumulative deformation of the temporary coherent pixel points.

10. A computer-readable storage medium, characterized by comprising a program executable by a processor to implement the method of any one of claims 1-8.

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