Mining area large-gradient deformation three-dimensional calculation method based on monorail InSAR

Abstract

The invention relates to a single-rail InSAR-based mining area large-gradient deformation three-dimensional calculation method, which comprises the following steps of: performing interference processing on InSAR data to obtain an interference pattern, acquiring mining area earth surface deformation by a prediction or actual measurement method, and converting the mining area earth surface deformation into a deformation phase as a reference phase; removing a reference phase from an InSAR interferometric phase to obtain an interferogram residual wrapping phase with reduced fringe density and reduced unwrapping difficulty; unwrapping the residual winding phase to obtain a residual phase, and superposing the residual phase with the reference phase to realize the repair of the InSAR deformation phase; deducing a surface movement vector depression angle function; based on the earth surface point movement vector depression angle function, the earth surface point horizontal movement vector direction and the radar beam LOS direction space parameters, the expression of the included angle between the LOS direction and the earth surface movement vector is solved, and earth surface three-dimensional deformation is solved through monorail InSAR deformation.

Description

Technical Field

[0001] The invention relates to the technical field of surface deformation calculation, and in particular to a three-dimensional calculation method for large gradient deformation in a mining area based on a single-track InSAR. Background Art

[0002] The large-scale mining of coal resources has brought huge social and economic benefits and promoted rapid economic development. However, it has also caused many geological disasters and ecological damage, such as building damage, road deformation and subsidence, groundwater level reduction, surface damage, etc. Therefore, monitoring and studying the surface deformation caused by mining subsidence plays a vital role in the prevention and control of geological environmental disasters in mining areas.

[0003] As a rapidly developing satellite-based earth observation technology with broad application prospects, InSAR has been widely used in surface deformation monitoring. The surface deformation caused by underground coal mining has the characteristics of fast speed and large gradient, which has always been an important research field of InSAR technology. Although InSAR technology has achieved many effective engineering applications and research results in monitoring surface deformation in mining areas, it is still facing many problems due to the characteristics of the technology itself and the deformation characteristics of mining areas.

[0004] First, the surface deformation caused by underground coal mining has the characteristics of fast change speed, large deformation gradient and nonlinear deformation. These characteristics easily cause the deformation gradient in the central area of ​​the sinking basin to exceed the deformation monitoring capability of InSAR technology. The phase of the interference pattern in the central area is discontinuous, and phase unwrapping is difficult to perform effectively, so that the deformation phase information cannot be accurately restored. Therefore, relying on the traditional phase unwrapping method can only effectively obtain small-scale deformations in the edge area of ​​the mining area, and cannot effectively extract large-scale and large-gradient deformations.

[0005] In addition, InSAR monitors one-dimensional deformation in the LOS direction, which is the projection of the actual surface deformation in the direction of the radar beam. The actual surface deformation in the mining area is three-dimensional, and the one-dimensional deformation in the LOS direction cannot accurately describe the actual deformation of the mining area. The existing technology uses InSAR technology to study the method of obtaining three-dimensional surface deformation in mining areas. The data requirements of multi-orbit InSAR observation methods are difficult to meet, and the single-orbit InSAR observation method also has some problems. Chinese patent CN116719028A discloses a large gradient phase optimization method for mining areas based on a probability integral model, a priori model + single-orbit InSAR observation, by adding constraints to the equations between LOS deformation and subsidence, east-west and north-south deformation, to achieve the acquisition of three-dimensional information. The probability integral model of this method requires precise prediction parameters and mining area advancement data to more accurately obtain the prior phase. Chinese patent CN116719028A discloses a large gradient phase optimization method for mining areas based on a probability integral model, a priori model + single-orbit InSAR observation, by adding constraints to the equations between LOS deformation and subsidence, east-west and north-south deformation, to achieve the acquisition of three-dimensional information. The probability integral model of this method requires precise prediction parameters and mining area advancement data to more accurately obtain the prior phase. CN114089335B discloses a method for extracting three-dimensional deformation of mining subsidence in mountainous areas based on single-track InSAR. According to the spatial geometric relationship between the three-dimensional surface deformation caused by mining and the LOS deformation obtained by InSAR technology, a functional relationship between the two is established for any point (i, j) on the surface; the function calculates the vertical, north-south and east-west deformation components from the LOS deformation variable, and solves the three equations by adding the horizontal surface movement caused by horizontal or near-horizontal coal seam mining that is proportional to the vertical deformation gradient as an additional constraint condition. For areas where the surface rises in the LOS direction, it cannot be restored to normal subsidence.

[0006] To address the above issues, this research team proposed a three-dimensional calculation method for large gradient deformation in mining areas based on single-track InSAR. Summary of the invention

[0007] The purpose of the present invention is to provide a three-dimensional calculation method for large gradient deformation in mining areas based on single-track InSAR, which makes up for the problem that traditional phase unwrapping methods are difficult to effectively unwrap in large gradient deformation mining areas and single-track InSAR is difficult to solve the three-dimensional deformation of the mining area surface.

[0008] A three-dimensional calculation method for large gradient deformation in a mining area based on a single-track InSAR comprises the following steps:

[0009] S100, performing interference processing on the InSAR data to obtain an interference pattern; obtaining the surface deformation of the mining area by a prediction method or actual measurement and converting it into a deformation phase as a reference phase;

[0010] S200, removing the reference phase from the InSAR interferometric phase to obtain the interferogram residual entanglement phase with reduced fringe density and reduced unwrapping difficulty;

[0011] S300, unwrapping the remaining wrapped phase to obtain a remaining phase, and superimposing the remaining phase with the reference phase to achieve repair of the InSAR deformation phase;

[0012] S400, deriving a depression angle function of a surface movement vector;

[0013] S500, based on the depression angle function of the surface point movement vector, the direction of the surface point horizontal movement vector and the LOS direction spatial parameter of the radar beam, solve the expression of the angle between the LOS direction and the surface movement vector, so as to realize the calculation of the three-dimensional deformation of the surface from the single-track InSAR deformation.

[0014] Furthermore, the S100 performs interference processing on the InSAR data to obtain an interference pattern, specifically,

[0015] DInSAR: The interferometric phase is related to the reference ellipsoid, the position of the ground point, the surface deformation, the atmospheric delay and various system noises. The interferometric phase is expressed as follows:

[0016]

[0017] Track error Can be eliminated using precise orbital data; and φ noise are atmospheric delay and noise phase, respectively, which can be weakened by phase filtering; therefore, the main factors of interference phase are: the flat earth phase of the reference ellipsoid Terrain Phase and deformation phase

[0018] DInSAR technology is based on the InSAR interferometric phase, and is differentiated from the DEM simulation phase to eliminate the terrain phase and obtain the surface deformation phase information. When the surface is deformed, assuming that Δρ is the deformation in the LOS direction, the deformation phase can be obtained according to the interferometric theory:

[0019]

[0020] in,

[0021]

[0022] The first term on the right side of the equation is the distance corresponding to the interference phase, the second term corresponds to the flat ground effect, and the third term corresponds to the terrain, which can be removed using external DEM data.

[0023] For the reference phase, it is obtained by converting the predicted or measured surface deformation into the deformation phase;

[0024] Assume that the mining subsidence area prediction method or the measured ground subsidence w and horizontal movement u are obtained, then the LOS deformation phase φ represented by them is w and φ u Respectively expressed as:

[0025]

[0026] Where θ is the radar incident angle, γ is the difference between the LOS azimuth and the azimuth of the horizontal movement direction of the surface, that is, the angle between the horizontal movement direction of the surface and the projection line of the LOS on the horizontal plane;

[0027] The estimated or measured method may be UAV oblique photogrammetry, Airborne LIDAR, OT technology, ground-based 3DLaser Scanning, GNSS or PIM method. The estimated or measured deformation accuracy is generally low. Based on the reference phase and InSAR interferometric phase, this method can be used to repair the InSAR deformation phase of a mining area with a large gradient deformation.

[0028] Furthermore, the S200 removes the reference phase from the InSAR interference phase to obtain the interference pattern residual entanglement phase with reduced fringe density and reduced unwrapping difficulty, specifically,

[0029] InSAR phase can be expressed by the wrapping phase and the number of phase integer cycles:

[0030]

[0031] In the formula, φ defo is the LOS-to-InSAR deformation phase, which is φ u With φ w sum; is the InSAR interferometric twisting phase, with a value range of (-π, π); n defo It is an integer multiple of the actual deformation phase.

[0032] The reference phase obtained in S100 is converted into a winding phase, which is expressed as:

[0033]

[0034] In the formula, φ ref is the LOS phase φ corresponding to the measured or expected sinking w LOS phase φ corresponding to horizontal shift u sum; n ref is an integer multiple of the deformation phase; is the winding phase, and its value range is (-π, π).

[0035] By removing the reference deformation phase from the real InSAR deformation phase, the interferogram residual phase and the winding phase of the residual phase can be obtained, which can be expressed as:

[0036]

[0037] In the formula, φ diffis the residual phase of the interference phase; Yes diff The winding phase is expressed as Its value is also between (-π, π); n defo -n ref +m is the integer multiple of the residual phase. The difference is lower than the difference between the corresponding adjacent pixels in the real phase, which reduces the density of fringes and the difficulty of phase unwrapping, making it possible to restore the real deformation phase.

[0038] Furthermore, the S300 unwraps the remaining wrapped phase to obtain a remaining phase, and the remaining phase is superimposed on the reference phase to repair the InSAR deformation phase, specifically,

[0039] The goal of minimum cost flow untangling is to make the total cost J MCF Minimum:

[0040]

[0041] In the formula, is the flow cost in the x direction, is the flow cost in the y direction; Represents the flow from point (i,j) to point (i+1,j), represents the flow from point (i,j) to point (i,j+1). To reduce the number of operations, extract the original residual point and search for the path with the minimum cost. The above formula is converted to:

[0042] J MCF =min∑ ω c ω |f ω |;

[0043] Convert it to a linear problem, that is

[0044]

[0045] In solving J MCF When the minimum value is reached, starting from the point where the flow is zero, one flow with the minimum cost is added in sequence until all residual points reach a break-even point.

[0046] The residual winding phase of the InSAR interferometric phase After phase unwrapping, the residual phase φ is obtained diff , then the real InSAR deformation phase of the surface is restored.

[0047] φ defo =φ ref +φ diff ;

[0048] Furthermore, the S400 derives the ground surface movement vector depression angle function, specifically,

[0049] The probability integral method is used to simulate the surface deformation caused by underground mining. The probability integral method is a method for predicting surface movement and deformation based on the probability density function of the normal distribution. It is the most mature and widely used mining subsidence prediction method in my country. For horizontally mined coal seams, assuming that the prediction parameters of the strike and dip directions are the same, the subsidence expression of the probability integral method is as follows:

[0050]

[0051] in:

[0052]

[0053] Wherein, m is the mining thickness, q is the subsidence coefficient, α is the coal seam inclination; H is the average mining depth, H1 and H2 are the mining depths in the downhill and uphill directions, tanβ is the tangent of the main influencing angle, s is the inflection point offset, and s includes the inflection point offsets s1 and s2 of the strike main section and the inflection point offsets s3 and s4 of the dip main section, and θ is the mining influence propagation angle.

[0054] The horizontal shift expression is:

[0055]

[0056] Where U°(x) and U°(y) are:

[0057]

[0058] Where b is the horizontal movement coefficient of the strike main section, b1 and b2 are the horizontal movement coefficients of the uphill and downhill directions of the dip main section.

[0059] In order to obtain the depression angle of the moving vector of any point on the surface of the subsidence basin, it is also necessary to know the maximum horizontal movement of the surface point. The direction of the maximum surface inclination is the actual horizontal movement direction of the surface point, which is the true horizontal movement. Tilt of direction is the maximum surface subsidence w(x,y) at The first derivative of the direction, that is

[0060]

[0061] In the formula, i°(x) is the inclination value of the point with abscissa x on the main section of the strike when the dip is fully mined; i°(y) is the inclination value of the point with abscissa y on the main section of the dip when the dip is fully mined. Assume that the maximum inclination direction is According to the extreme value principle:

[0062]

[0063] The above two equations can be used to obtain the horizontal movement direction of any point on the surface of the moving basin:

[0064]

[0065] Then the moving vector depression angle of any point on the surface can be expressed as:

[0066]

[0067] Furthermore, the S500 solves the expression of the angle between the LOS direction and the surface movement vector based on the depression angle function of the surface point movement vector, the direction of the surface point horizontal movement vector and the LOS direction spatial parameter of the radar beam, so as to calculate the three-dimensional surface deformation from the repaired single-track InSAR deformation, specifically,

[0068] The angle ω between the LOS deformation vector and the ground movement vector changes with the pitch angle β s changes with the change, so we can establish the independent variable β s The functional relationship between and the dependent variable ω. According to the spatial geometric relationship, the following relationship can be deduced:

[0069] cosω=[cosθ sinθ]·[sinβ s cosβ s ·cosγ] T ;

[0070] Where, γ is the azimuth angle to LOS and d horizontal The difference in azimuth angle χ is the angle between the projection line of the LOS direction on the horizontal plane and the horizontal movement vector of the surface point; θ is the angle of incidence, which is the angle between the radar beam and the vertical line.

[0071] The calculation formulas for the three-dimensional deformation of sinking, east-west, and north-south directions are obtained from the spatial relationship:

[0072]

[0073] The beneficial effects of the present invention are:

[0074] 1. The present invention establishes an InSAR deformation phase repair calculation method by superimposing the reference phase with the residual phase. The reference phase is obtained by the prediction or measurement method, so as to achieve effective unwrapping in the large gradient deformation mining area.

[0075] 2. The present invention proposes a computational model for calculating the three-dimensional deformation of the surface of a moving basin by the repaired single-track InSAR LOS deformation based on the depression angle function of the surface movement vector, the horizontal movement direction of the surface point and the LOS spatial parameters of the radar beam, thereby realizing the single-track InSAR solution of the three-dimensional deformation of the surface of the mining area. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Figure 1 It is a schematic diagram of the process of the present invention;

[0077] Figure 2 A schematic diagram of a reference phase repair method of the present invention;

[0078] Figure 3 This is a schematic diagram of the calculation process of three-dimensional deformation of the mining area surface by single-track InSAR in Example 1 of the present invention;

[0079] Figure 4 This is a schematic diagram of the implementation mode of large gradient three-dimensional deformation monitoring in Example 1 of the present invention. DETAILED DESCRIPTION

[0080] The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. The exemplary embodiments and descriptions of the present invention are used to explain the present invention but are not intended to limit the present invention.

[0081] Example 1

[0082] This embodiment is implemented based on horizontal mining of coal seams.

[0083] refer to Figure 1-Figure 3 A three-dimensional calculation method for large gradient deformation in mining areas based on single-track InSAR includes the following steps:

[0084] S100 performs interference processing on InSAR data and obtains the interference diagram as follows:

[0085] DInSAR: The interferometric phase is related to the reference ellipsoid, the position of the ground point, the surface deformation, the atmospheric delay and various system noises. The interferometric phase is expressed as follows:

[0086]

[0087] Track error Can be eliminated using precise orbital data; and φ noise are atmospheric delay and noise phase, respectively, which can be weakened by phase filtering; therefore, the main factors of interference phase are: the flat earth phase of the reference ellipsoid Terrain Phase and deformation phase

[0088] Based on the InSAR interferometric phase, the terrain phase is eliminated by difference with the DEM simulation phase to obtain the surface deformation phase information; the surface is deformed, assuming that Δρ is the deformation in the LOS direction, then according to the interferometric theory, the deformation phase can be obtained as:

[0089]

[0090] in,

[0091]

[0092] The first term on the right side of the equation is the distance corresponding to the interference phase, the second term corresponds to the flat ground effect, and the third term corresponds to the terrain, which can be removed by external DEM data;

[0093] The surface deformation of the mining area is obtained by the prediction method or the measured value and converted into a deformation phase as a reference phase;

[0094] The estimated or measured method may be UAV oblique photogrammetry, Airborne LIDAR, OT technology, ground-based 3DLaser Scanning, GNSS or PIM method. The estimated or measured deformation accuracy is generally low. Based on the reference phase and InSAR interferometric phase, this method can be used to repair the InSAR deformation phase of a mining area with a large gradient deformation.

[0095] Assume that the mining subsidence area prediction method or the measured ground subsidence w and horizontal movement u are obtained, then the LOS deformation phase φ represented by them is w and φ u Respectively expressed as:

[0096]

[0097] Where θ is the radar incident angle, γ is the difference between the LOS azimuth and the azimuth of the horizontal movement direction of the surface, that is, the angle between the horizontal movement direction of the surface and the projection line of the LOS on the horizontal plane;

[0098] S200 removes the reference phase from the InSAR interferometric phase to obtain the residual entanglement phase of the interferogram with reduced fringe density and less difficulty in unwrapping. Specifically,

[0099] InSAR deformation phase can be expressed by the wrapping phase and the number of phase integers:

[0100]

[0101] In the formula, φ defo is the LOS-to-InSAR deformation phase, which is φ u With φ w sum; is the InSAR interferometric twisting phase, with a value range of (-π, π); n defo It is an integer multiple of the actual deformation phase.

[0102] The reference phase obtained in S100 is converted into a winding phase, which is expressed as:

[0103]

[0104] In the formula, φ ref is the LOS phase φ corresponding to the measured or expected sinking w LOS phase φ corresponding to horizontal shift u sum; n ref is an integer multiple of the deformation phase; is the winding phase, and its value range is (-π, π).

[0105] The reference deformation phase is removed from the real InSAR deformation phase to obtain the residual phase and the winding phase of the residual phase, which can be expressed as:

[0106]

[0107] In the formula, φ diff is the residual phase of the interference phase; Yes diff The winding phase is expressed as Its value is also between (-π, π); n defo -n ref +m is the integer multiple of the residual phase. At this time, the winding phase between adjacent pixels The difference is lower than the difference between the corresponding adjacent pixels in the real phase, which reduces the density of fringes and the difficulty of phase unwrapping, making it possible to restore the real deformation phase.

[0108] S300 unwraps the remaining wrapped phase to obtain the remaining phase, and the remaining phase is superimposed on the reference phase to repair the InSAR deformation phase. Specifically,

[0109] The goal of minimum cost flow untangling is to make the total cost J MCF Minimum:

[0110]

[0111] In the formula, is the flow cost in the x direction, is the flow cost in the y direction; Represents the flow from point (i,j) to point (i+1,j), represents the flow from point (i,j) to point (i,j+1). To reduce the number of operations, extract the original residual point and search for the path with the minimum cost. The above formula is converted to:

[0112] J MCF =min∑ ω c ω |f ω |;

[0113] Convert it to a linear problem, that is

[0114]

[0115] In solving J MCF When the minimum value is reached, starting from the point where the flow is zero, one flow with the minimum cost is added in sequence until all residual points reach a break-even point.

[0116] The residual winding phase of the InSAR interferometric phase After phase unwrapping, the residual phase φ is obtained diff , then the real deformation phase of the surface InSAR is restored;

[0117] φ defo =φ ref +φ diff ;

[0118] S400 derives the ground motion vector pitch function, specifically,

[0119] The probability integral method is used to simulate the surface deformation caused by underground mining. The probability integral method is a method for predicting surface movement and deformation based on the probability density function of the normal distribution. It is the most mature and widely used mining subsidence prediction method in my country. For horizontally mined coal seams, assuming that the prediction parameters of the strike and dip directions are the same, the subsidence expression of the probability integral method is as follows:

[0120]

[0121] in:

[0122]

[0123] Wherein, m is the mining thickness, q is the subsidence coefficient, α is the coal seam inclination; H is the average mining depth, H1 and H2 are the mining depths in the downhill and uphill directions, tanβ is the tangent of the main influencing angle, s is the inflection point offset, and s includes the inflection point offsets s1 and s2 of the strike main section and the inflection point offsets s3 and s4 of the dip main section, and θ is the mining influence propagation angle.

[0124] The horizontal shift expression is:

[0125]

[0126] Where U°(x) and U°(y) are:

[0127]

[0128] Where b is the horizontal movement coefficient of the strike main section, b1 and b2 are the horizontal movement coefficients of the uphill and downhill directions of the dip main section.

[0129] In order to obtain the depression angle of the moving vector of any point on the surface of the subsidence basin, it is also necessary to know the maximum horizontal movement of the surface point. The direction of the maximum surface inclination is the actual horizontal movement direction of the surface point, which is the true horizontal movement. Tilt of direction is the maximum surface subsidence w(x,y) at The first derivative of the direction, that is,

[0130]

[0131] In the formula, i°(x) is the inclination value of the point with abscissa x on the main section of the strike when the dip is fully mined; i°(y) is the inclination value of the point with abscissa y on the main section of the dip when the dip is fully mined. Assume that the maximum inclination direction is According to the extreme value principle:

[0132]

[0133] The above two equations can be used to obtain the horizontal movement direction of any point on the surface of the moving basin:

[0134]

[0135] Then the moving vector depression angle of any point on the surface can be expressed as:

[0136]

[0137] S500 solves the expression of the angle between the LOS direction and the surface movement vector based on the depression angle function of the surface point movement vector, the direction of the surface point horizontal movement vector and the LOS direction spatial parameters of the radar beam, and realizes the calculation of the three-dimensional surface deformation from the repaired single-track InSAR deformation. Specifically,

[0138] The angle ω between the LOS deformation vector and the ground movement vector changes with the pitch angle β s changes with the change, so we can establish the independent variable β s The functional relationship between and the dependent variable ω. According to the spatial geometric relationship, the following relationship can be deduced:

[0139] cosω=[cosθ sinθ]·[sinβ s cosβ s ·cosγ] T ;

[0140] Where, γ is the azimuth angle to LOS and d horizontal The difference in azimuth angle χ is the angle between the projection line of the LOS direction on the horizontal plane and the horizontal movement vector of the surface point; θ is the angle of incidence, which is the angle between the radar beam and the vertical line.

[0141] The calculation formulas for the three-dimensional deformation of sinking, east-west, and north-south directions are obtained from the spatial relationship:

[0142]

[0143] Although the present invention has been described in detail above by general explanation and specific implementation methods, it is obvious to those skilled in the art that some modifications or improvements can be made on the basis of the present invention. Therefore, these modifications or improvements made on the basis of not departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A three-dimensional calculation method for large gradient deformation in mining areas based on single-track InSAR, characterized in that: The following steps are involved: S100, performing interference processing on the InSAR data to obtain an interference pattern; obtaining the surface deformation of the mining area by a prediction or measurement method and converting it into a deformation phase as a reference phase; S200, removing the reference phase from the InSAR interferometric deformation phase to obtain the interferogram residual entanglement phase with reduced fringe density and reduced untangling difficulty; S300, unwrapping the remaining wrapped phase to obtain a remaining phase, and superimposing the remaining phase with the reference phase to achieve repair of the InSAR deformation phase; S400, deriving a depression angle function of a surface movement vector; S500, based on the depression angle function of the surface point movement vector, the direction of the surface point horizontal movement vector and the LOS direction spatial parameter of the radar beam, solve the expression of the angle between the LOS direction and the surface movement vector, so as to realize the calculation of the three-dimensional deformation of the surface from the single-track InSAR deformation.

2. The three-dimensional calculation method of large gradient deformation in mining areas based on single-track InSAR according to claim 1 is characterized in that: The S100 specifically includes the following steps: The interference phase is expressed as follows: in, is the orbit error phase, is the atmospheric delay phase, is the noise phase; the main factors of the interference phase are: the flat earth phase of the reference ellipsoid Terrain Phase and deformation phase Based on the InSAR interferometric phase, the terrain phase is eliminated by difference with the DEM simulation phase to obtain the surface deformation phase information; the surface is deformed, assuming that Δρ is the deformation amount in the LOS direction, then the deformation phase is: in, The first term on the right side of the equation is the distance corresponding to the interference phase, the second term corresponds to the flat ground effect, and the third term corresponds to the terrain, which is removed by external DEM data. For the reference phase, it is obtained by converting the predicted or measured surface deformation into the deformation phase; The mining subsidence area prediction method or measured values ​​can obtain the surface subsidence w and horizontal movement u, and the LOS deformation phase φ represented by them is w and φ u Respectively expressed as: Where θ is the radar incident angle, and γ is the difference between the LOS azimuth and the azimuth of the horizontal movement direction of the surface, that is, the angle between the horizontal movement direction of the surface and the projection line of the LOS direction on the horizontal plane.

3. The three-dimensional calculation method of large gradient deformation in mining areas based on single-track InSAR according to claim 1 is characterized in that: The S200 specifically includes the following steps: InSAR deformation phase is represented by the winding phase and the number of phase integers: In the formula, φ defo is the LOS-toward InSAR deformation phase; is the interference winding phase, and its value range is (-π, π); n defo is an integer multiple of the deformation phase; The reference phase obtained in S100 is converted into a winding phase, which is expressed as: In the formula, φ ref is the LOS phase φ corresponding to the measured or expected sinking w LOS phase φ corresponding to horizontal shift u sum; n ref is an integer multiple of the deformation phase; is the winding phase, and its value range is (-π, π).

4. The three-dimensional calculation method of large gradient deformation in mining areas based on single-track InSAR according to claim 4 is characterized in that: The S200 further includes the following steps: The reference deformation phase is removed from the InSAR real deformation phase to obtain the residual phase and the winding phase of the residual phase, which is expressed as: In the formula, φ diff is the residual phase of the InSAR interferometric phase; Yes diff The winding phase is expressed as Its value is between (-π, π); n defo -n ref +m is the integer multiple of the residual phase.

5. The three-dimensional calculation method of large gradient deformation in mining areas based on single-track InSAR according to claim 1 is characterized in that: The S300 specifically includes the following steps: Make the total cost J MCF Minimum: In the formula, is the flow cost in the x direction, is the flow cost in the y direction; Represents the flow from point (i,j) to point (i+1,j), Represents the flow from point (i,j) to point (i,j+1); Extract the original residual point and search for the path with the minimum cost. The above formula is converted to: J MCF =min∑ ω c ω |f ω |; Convert it to a linear problem, that is In solving J MCF Minimum value, starting from the point where the flow is zero, add a flow with the minimum cost one by one until all residual points reach break-even; The residual winding phase of the InSAR interferometric phase After phase unwrapping, the residual phase φ is obtained diff , then the real deformation phase of the surface InSAR is restored; f defo =φ ref +φ diff 。 6. The three-dimensional calculation method of large gradient deformation in mining areas based on single-track InSAR according to claim 1 is characterized in that: The S400 specifically includes the following steps: Underground mining causes surface deformation. Assuming that the predicted parameters in the strike and dip directions are the same, the subsidence expression is as follows: in, Where m is the mining thickness, q is the sinking coefficient, α is the coal seam inclination; H is the average mining depth, H1 and H2 are the mining depths in the downhill and uphill directions, tanβ is the main influencing angle tangent, s1 and s2 are the inflection point offsets of the main section in the direction of the strike, s3 and s4 are the inflection point offsets of the main section in the direction of the dip, and θ is the mining influence propagation angle; The horizontal shift expression is: Where U°(x) and U°(y) are: Where b is the horizontal movement coefficient of the strike main section, b1 and b2 are the horizontal movement coefficients of the uphill and downhill directions of the dip main section.

7. The three-dimensional calculation method of large gradient deformation in mining areas based on single-track InSAR according to claim 1 is characterized in that: The S400 further includes the following steps: The maximum surface inclination direction is the actual horizontal movement direction of the surface point. This direction is the true horizontal movement amount. Tilt of direction is the maximum surface subsidence w(x,y) at The first derivative of the direction, that is, Where i°(x) is the inclination value of the point with abscissa x on the main section of the strike when the strike is fully mined, i°(y) is the inclination value of the point with abscissa y on the main section of the strike when the strike is fully mined, and the maximum inclination direction is but, The horizontal movement direction of any point on the surface of the moving basin can be obtained from the above two equations: The moving vector depression angle of any point on the surface is expressed as:

8. The three-dimensional calculation method of large gradient deformation in mining areas based on single-track InSAR according to claim 1 is characterized in that: The S500 specifically includes the following steps: The angle between the LOS deformation vector and the ground movement vector is ω, and the depression angle is β s , according to the spatial geometric relationship, there is the following relationship: cosω=[cosθsinθ]·[sinβ s cosβ s ·cosγ] T ; Where, γ is the azimuth angle to LOS and d horizontal The difference in azimuth angle χ is the angle between the projection line of the LOS direction on the horizontal plane and the horizontal moving vector of the surface point; θ is the angle of incidence, that is, the angle between the radar beam and the vertical line; The calculation formulas for the three-dimensional deformation of sinking, east-west, and north-south directions are obtained from the spatial relationship:

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