Gravity field reconstruction method, system, electronic device and storage medium

Abstract

The present invention relates to a gravity field reconstruction method, system, electronic device, and storage medium, and relates to the field of gravity potential field data processing. The method comprises determining point mass coordinates based on observation point coordinates; equally dividing the point mass coordinates and observation point coordinates to obtain observation point data blocks and point mass data blocks; inverting physical property values ​​of a point mass data block corresponding to the observation point data block using the observation point data block; determining a residual gravity anomaly of the observation point data block based on the physical property values; determining whether the root mean square of the residual gravity anomaly is less than a set threshold; if not, using the residual gravity anomaly as observation data of the observation point data block to re-invert the physical property values ​​of the point mass data block corresponding to the observation point data block; if so, determining a global point mass model based on the physical property values ​​of the point mass data block and the position of the point mass in the point mass data block; and calculating the gravitational vector of the disturbance in the Earth's external space based on the global point mass model. The present invention can improve the reconstruction speed of the gravity field.

Description

Technical Field

[0001] The present invention relates to the field of gravity potential field data processing, and in particular to a gravity field reconstruction method, system, electronic equipment and storage medium. Background Art

[0002] A point mass model refers to a system of virtual particles distributed underground with a defined spatial distribution and physical property values. The spatial distribution refers to the location of the particles, which can be determined using longitude, latitude, and burial depth in a spherical coordinate system. The longitude and latitude coordinates are typically consistent with the observation point, while the burial depth can be determined empirically. The physical property value refers to the mass of the particles, which is determined by establishing and solving a set of observation equations. In gravity potential field data processing, the point mass model is widely used to reconstruct the Earth's gravity field due to its high computational speed and accuracy.

[0003] Typically, point mass models of the local gravity field are constructed. However, with the increasing demand for high-precision global gravity field data for various aircraft, research is needed to rapidly model and reconstruct high-resolution global point mass data. When constructing point mass models of the local gravity field, the mass points are typically placed on a sphere located within the Earth (the Bjerhammar sphere). However, for global point mass models, the grid distortion of the gravity data increases as the data resolution increases. When the mass points are distributed on the Bjerhammar sphere, the condition number of the observation equations increases rapidly, resulting in poor solution stability and even unsolvable solutions. To address this issue, new spatial distribution methods for global point mass models are needed. When constructing global point mass models, a block-by-block iterative method can be used to solve for physical property parameters. However, this iteration requires repeated calculation and storage of the coefficient matrix of the observation equations, which slows down the construction of the point mass model. When reconstructing the gravity field, a spherical harmonic coefficient model is often used, but this is extremely inefficient for reconstructing high-resolution global gravity fields. While using a global point mass model can significantly improve computational efficiency, the coefficient matrix for the Earth's gravity field requires repeated calculation and storage at every altitude, severely limiting the efficiency of gravity field support for various aircraft. Therefore, research is needed to optimize the coefficient matrix. Summary of the Invention

[0004] The purpose of the present invention is to provide a gravity field reconstruction method, system, electronic equipment and storage medium to improve the reconstruction speed of the gravity field.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A gravity field reconstruction method, comprising:

[0007] Get the coordinates of the observation point on the earth's surface;

[0008] determining point mass coordinates based on the observed point coordinates;

[0009] Dividing the point quality coordinates and the observation point coordinates equally to obtain observation point data blocks and point quality data blocks;

[0010] Inverting the physical property value of the point mass data block corresponding to the observation point data block using the observation point data block;

[0011] determining a residual gravity anomaly of the observation point data block based on the physical property values ​​of the point mass data block;

[0012] Determining whether the root mean square of the residual gravity anomaly is less than a set threshold, and obtaining a determination result;

[0013] If the judgment result is no, the residual gravity anomaly is used as the observation data of the observation point data block, and the process returns to the step of "using the observation point data block to invert the physical property value of the point mass data block corresponding to the observation point data block";

[0014] If the judgment result is yes, determining a global point mass model according to the physical property values ​​of the point mass data block and the positions of the point masses in the point mass data block;

[0015] The gravitational vector of the disturbance in the Earth's external space is calculated according to the global point mass model; the gravitational vector of the disturbance in the Earth's external space is used to reconstruct the gravity field.

[0016] Optionally, the step of equally dividing the point quality coordinates and the observation point coordinates to obtain an observation point data block and a point quality data block specifically includes:

[0017] Dividing the point quality coordinates equally along the longitude and latitude directions to obtain point quality data blocks;

[0018] The observation point coordinates are equally divided along the longitude and latitude directions to obtain observation point data blocks.

[0019] Optionally, determining the residual gravity anomaly of the observation point data block according to the physical property value of the point mass data block specifically includes:

[0020] Determining an observation equation based on the physical property values ​​of the point mass data block and the gravity anomaly observation value of the observation point data block;

[0021] The residual gravity anomaly of the measuring point data block is determined according to the physical property values ​​of the point mass data block and the gravity anomaly observation value of the measuring point data block using the observation equation.

[0022] Optionally, the global point mass model includes the position of the point mass data block and the physical property value of the point mass data block.

[0023] Optionally, the expression of the gravitational force vector of the external space disturbance of the Earth is:

[0024]

[0025] in, To calculate the radial component of the point perturbation gravity, To calculate the latitude component of the gravity of the point disturbance, To calculate the longitudinal component of the point disturbance gravity, s p Point quality data block Q pq The starting point number in the latitude direction of the midpoint mass, s p+1 Point quality data block Q pq The end point number in the latitude direction of the midpoint mass, t q Point quality data block Q pq The starting point number in the longitude direction of the midpoint mass, t q+1 Point quality data block Q pq The endpoint number in the longitude direction of the midpoint mass, G is the gravitational constant, m st is the physical property value of the mass of the point in the sth row and tth column, is the first coefficient of the equation, is the second coefficient of the equation, is the third coefficient of the equation, R st is the distance from the point mass to the center of the Earth; Point mass To calculation point distance; Point mass and calculation points The angular distance between the sphere centers, is the azimuth, is the latitude coordinate of the point mass, λ t is the longitude coordinate of the point mass, r pq is the geocentric radius of the calculation point, is the latitude coordinate of the calculation point, λ q The longitude coordinate of the calculation point.

[0026] The present invention also provides a gravity field reconstruction system, comprising:

[0027] An acquisition module is used to obtain the coordinates of observation points on the earth's surface;

[0028] a point mass coordinate determination module, configured to determine the point mass coordinates according to the observed point coordinates;

[0029] an equal division module, configured to equally divide the point quality coordinates and the observation point coordinates to obtain observation point data blocks and point quality data blocks;

[0030] an inversion module, configured to use the observation point data block to invert the physical property value of the point mass data block corresponding to the observation point data block;

[0031] a residual gravity anomaly determination module, configured to determine the residual gravity anomaly of the observation point data block based on the physical property values ​​of the point mass data block;

[0032] a judgment module, configured to judge whether the root mean square of the residual gravity anomaly is less than a set threshold value, and obtain a judgment result;

[0033] an updating and returning module, configured to use the residual gravity anomaly as the observation data of the observation point data block and return the result to the inversion module if the judgment result is negative;

[0034] a global point mass model determination module, configured to determine a global point mass model according to the physical property values ​​of the point mass data block and the position of the point mass in the point mass data block if the judgment result is yes;

[0035] The module for determining the gravitational vector of the disturbance in the earth's external space is used to calculate the gravitational vector of the disturbance in the earth's external space according to the global point mass model; the gravitational vector of the disturbance in the earth's external space is used to reconstruct the gravity field.

[0036] Optionally, the bisection module specifically includes:

[0037] a point quality coordinate dividing unit, configured to divide the point quality coordinates equally along the longitude and latitude directions to obtain point quality data blocks;

[0038] The observation point coordinate dividing unit is used to divide the observation point coordinates equally along the longitude direction and the latitude direction respectively to obtain observation point data blocks.

[0039] Optionally, the residual gravity anomaly determination module specifically includes:

[0040] an observation equation determining unit, configured to determine an observation equation based on the physical property values ​​of the point mass data block and the gravity anomaly observation value of the observation point data block;

[0041] The residual gravity anomaly determination unit is used to determine the residual gravity anomaly of the measuring point data block according to the physical property values ​​of the point mass data block and the gravity anomaly observation value of the measuring point data block using the observation equation.

[0042] The present invention also provides an electronic device, comprising:

[0043] one or more processors;

[0044] a storage device having one or more programs stored thereon;

[0045] When the one or more programs are executed by the one or more processors, the one or more processors are enabled to implement any one of the methods described above.

[0046] The present invention also provides a computer storage medium having a computer program stored thereon, wherein the computer program implements any of the above methods when executed by a processor.

[0047] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0048] The present invention obtains observation point coordinates on the surface of the earth; determines point mass coordinates based on the observation point coordinates; equally divides the point mass coordinates and the observation point coordinates to obtain an observation point data block and a point mass data block; uses the observation point data block to invert physical property values ​​of the point mass data block corresponding to the observation point data block; determines a residual gravity anomaly of the observation point data block based on the physical property values ​​of the point mass data block; determines whether a root mean square of the residual gravity anomaly is less than a set threshold; if not, uses the residual gravity anomaly as observation data of the observation point data block and returns to the step of "using the observation point data block to invert physical property values ​​of the point mass data block corresponding to the observation point data block"; if so, determines a global point mass model based on the physical property values ​​of the point mass data block and the position of the point mass in the point mass data block; calculates a gravitational vector of a disturbance in the earth's external space based on the global point mass model; and uses the gravitational vector of the disturbance in the earth's external space to reconstruct a gravity field. The present invention improves the stability of the solution of the observation equations, making high-resolution global point mass modeling based on traditional geographic grid data possible; it does not require repeated calculation and storage of coefficient matrices, and can achieve rapid construction of high-resolution global point mass models and rapid reconstruction of the Earth's external space gravity field. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0050] Figure 1 A schematic diagram of the gradual burial depth of the global point mass model provided by the present invention;

[0051] Figure 2 Schematic diagram of geometric architecture equivalence in modeling global point mass models;

[0052] Figure 3 Schematic diagram of geometrical framework equivalence in gravity field reconstruction;

[0053] Figure 4 This is a flow chart of the gravity field reconstruction method provided by the present invention. DETAILED DESCRIPTION

[0054] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0055] The purpose of the present invention is to provide a gravity field reconstruction method, system, electronic equipment and storage medium to improve the reconstruction speed of the gravity field.

[0056] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0057] like Figure 4 As shown, the present invention provides a gravity field reconstruction method, comprising:

[0058] Step 101: Obtain the coordinates of the observation point on the earth's surface.

[0059] Step 102: Determine point quality coordinates based on the observed point coordinates.

[0060] Given the longitude and latitude coordinates of the global point mass model, the “gradual depth method” is used to set the depth; for example Figure 1 As shown, Figure 1 This is a schematic diagram of the global point mass model's gradient depth. The outer circle (solid line) represents the Earth's surface, and the inner circle (dashed line) represents the Bjerhammar sphere. O represents the Earth's center, A and B represent two points on the equator, N represents the North Pole, and S represents the South Pole. Black dots represent point masses. The depth in low and mid-latitude regions is calculated as one times the latitudinal distance between the observation points, while the depth in high latitude regions is calculated as two times the longitudinal distance between the observation points. The longitude and latitude coordinates of these dots are consistent with those of the observation points (distributed on the Earth's surface in a geographic grid).

[0061] Step 103: Equally divide the point quality coordinates and the observation point coordinates to obtain an observation point data block and a point quality data block. Step 103 specifically includes: equally dividing the point quality coordinates along the longitude and latitude directions to obtain a point quality data block; equally dividing the observation point coordinates along the longitude and latitude directions to obtain an observation point data block.

[0062] Step 104: using the observation point data block to invert the physical property value of the point mass data block corresponding to the observation point data block.

[0063] Step 105: Determine the residual gravity anomaly of the observation point data block based on the physical property values ​​of the point mass data block. Step 105 specifically includes: determining an observation equation based on the physical property values ​​of the point mass data block and the gravity anomaly observation value of the observation point data block; and using the observation equation to determine the residual gravity anomaly of the measurement point data block based on the physical property values ​​of the point mass data block and the gravity anomaly observation value of the measurement point data block.

[0064] Step 106: Determine whether the root mean square of the residual gravity anomaly is less than a set threshold, and obtain a determination result.

[0065] If the judgment result is no, step 107 is executed; if the judgment result is yes, step 108 is executed.

[0066] Step 107: Use the residual gravity anomaly as the observation data of the observation point data block, and return to step 104.

[0067] Step 108: Determine a global point mass model based on the physical property values ​​of the point mass data block and the positions of the point masses in the point mass data block. The global point mass model includes the positions of the point mass data block and the physical property values ​​of the point mass data block.

[0068] The physical parameters of the global point mass model are solved by using the “block iteration method”. During the iteration process, the “geometric framework equivalence principle” is used to perform equivalent transformation on the coefficient matrix of the observation equation group; Figure 2 As shown, Figure 2 This is a schematic diagram of the geometric architecture equivalence in global point mass modeling. The black dots are point masses and the black triangles are observation points. ij (i=1,2,…,Nr,j=1,2,…,Mc) is the point quality data block in the i-th row and j-th column, Nr is the number of blocks in the latitude direction, and Mc is the number of blocks in the longitude direction. ij For S ij The observation data block directly above has a window radius of ρ1. ij For S ij with I ij The coefficient matrix of the observation equations (called geometric framework)

[0069] Step 109: Calculate the gravitational vector of the Earth's external space disturbance according to the global point mass model; the gravitational vector of the Earth's external space disturbance is used to reconstruct the gravity field.

[0070] The global point mass model is used to reconstruct the Earth's gravity field. During the reconstruction process, the "geometric framework equivalence principle" is used to perform equivalent transformation on the equation coefficient matrix. Figure 3 As shown, Figure 3 This is the principle diagram of geometric framework equivalence in gravity field reconstruction. The black dots are point masses and the black triangles are calculation points. pq (p=1,2,…,N,q=1,2,…,M) is the position of the calculation point, N is the number of calculation points in the latitude direction, and M is the number of calculation points in the longitude direction. pq is the point mass distribution area involved in the calculation, and the window radius is ρ2. pq O pq With Q pq The coefficient matrix of the system of equations (i.e., the geometric structure).

[0071] The expression of the gravitational force vector of the external space disturbance of the Earth is:

[0072]

[0073] in, To calculate the radial component of the point perturbation gravity, To calculate the latitude component of the gravity of the point disturbance, To calculate the longitudinal component of the point disturbance gravity, s p Point quality data block Q pq The starting point number in the latitude direction of the midpoint mass, s p+1 Point quality data block Q pq The end point number in the latitude direction of the midpoint mass, t q Point quality data block Q pq The starting point number in the longitude direction of the midpoint mass, t q+1 Point quality data block Q pq The endpoint number in the longitude direction of the midpoint mass, G is the gravitational constant, m st is the physical property value of the mass of the point in the sth row and tth column, is the first coefficient of the equation, is the second coefficient of the equation, is the third coefficient of the equation, R st is the distance from the point mass to the center of the earth, and R is the distance from the calculation point to the center of the earth; Point mass To calculation point distance; Point mass and calculation points The angular distance between the sphere centers, is the azimuth, is the latitude coordinate of the point mass, λ tis the longitude coordinate of the point mass, r pq is the geocentric radius of the calculation point, is the latitude coordinate of the calculation point, λ q The longitude coordinate of the calculation point.

[0074] The "gradual burial depth method" proposed in this invention improves the stability of the solution of the observation equation group, making high-resolution global point mass modeling based on traditional geographic grid data possible; the "geometric architecture equivalence principle" proposed in this invention improves the calculation and storage efficiency of the coefficient matrix, and can realize the rapid construction of high-resolution global point mass models and the rapid reconstruction of the gravity field outside the earth; the "global point mass rapid modeling and gravity field rapid reconstruction method and system" proposed in this invention can provide high-precision global rapid gravity field protection for various types of aircraft.

[0075] The present invention also provides a specific processing process for the gravity field reconstruction method in practical applications. First, the spatial distribution position of the global point mass model is set. The longitude and latitude coordinates of the point mass model are determined based on the observation point position, and the burial depth is set using the "gradual burial depth method." Then, the physical parameters of the global point mass model are solved using the "block iteration method." During the iteration process, the "geometric framework equivalence principle" is used to perform an equivalent transformation on the coefficient matrix of the observation equation group. Finally, the global point mass model is used to reconstruct the Earth's gravity field. During the reconstruction process, the "geometric framework equivalence principle" is used to perform an equivalent transformation on the coefficient matrix of the calculation equation. The specific steps are as follows:

[0076] Step 1: According to the observation point coordinates Determine the coordinates of a point mass

[0077] The observation points are distributed on the surface of the earth in the form of a geographic grid, with a distance R from the center of the earth and a latitude coordinate of The longitude coordinate is λ q (p=1,2,…,N, N is the number of rows of observation points in the latitude direction; q=1,2,…,M, M is the number of columns of observation points in the longitude direction), both are known quantities. The point mass is matched one by one with the observation point in the vertical direction to obtain the latitude coordinate of the point mass and longitude coordinate λ t (s=1,2,…,N,t=1,2,…,M). The observation point and the calculation point correspond one to one in the vertical direction. Their longitude and latitude coordinates are the same, but their distances to the center of the earth are different. The observation point is R and the calculation point is r pq .

[0078] like Figure 1 As shown, the “gradual burial depth method” is used, that is, the burial depth in low and medium latitude areas is taken as one times the distance between the observation points in the latitude direction, and the burial depth in high latitude areas is taken as twice the distance between the observation points in the longitude direction, and the burial depth d of the point mass is obtained. st, and then get the distance R from the point mass to the center of the earth st (R st =Rd st ).

[0079] Step 2: Take the window radius as ρ1 (for example, take ρ1 = 1), and set the point mass Divide into Nr equal parts along the latitude direction and Mc equal parts along the longitude direction. The same division is used. There is a relationship: Nr = N / (2ρ1), Mc = M / (2ρ1).

[0080] like Figure 2 As shown, the quality data block of the point in row i and column j is represented by S ij Indicates that the i-th row and j-th column observation point data block is represented by I ij Represents (i=1,2,…,Nr,j=1,2,…,Mc). Data block S ij Includes coordinates of point masses Transitivity value m st (s=s i ,s i +1,…,s i+1 , t=t j ,t j +1,…,t j+1 ), data block I ij Contains the coordinates of the observation points and gravity anomaly Δg pq (p=s i ,s i +1,…,s i+1 , q = t j ,t j +1,…,t j+1 ). The following relationship exists:

[0081] s i =2ρ1(i-1)+1,s i+1 =2ρ1i

[0082] t j =2ρ1(j-1)+1,t j+1 =2ρ1j

[0083] In the above parameters, m st is the quantity to be determined, the others are known quantities, s i is the row number of the point mass, t j is the column number of the point mass.

[0084] Step 3: Using observation point data block I 11 Invert the mass data block S of the point below it 11 Physical property value mst (s=s1,s1+1,…,s2,t=t1,t1+1,…,t2), and calculate the residual gravity anomaly at the observation point (p=1,2,…,N, q=1,2,…,M).

[0085] Point quality data block S 11 Physical property value m st and observation point data block I 11 The gravity anomaly Δg pq The relationship between (called the observation equation) is

[0086]

[0087]

[0088] Where: Δg pq is the gravity anomaly of the observation point in the pth row and qth column (p=s1,s1+1,…,s2,q=t1,t1+1,…,t2); s1 and s2 are S 11 Midpoint mass (or I 11 The starting and ending numbers of the latitude direction of the observation point) are t1 and t2, respectively. 11 Midpoint mass (or I 11 The starting and ending points in the longitude direction of the observation point (m), s1, s2, t1, t2 can be calculated according to step 2; st is the physical property value of the mass of the point in the sth row and tth column, which is the quantity to be determined; G is the gravitational constant; is the coefficient of the observation equation; R is the distance from the observation point to the center of the earth; R st is the distance from the point mass to the center of the earth (R st =Rd st ); Point mass To observation point distance Point mass and observation points The angular distance between the sphere centers is calculated according to the following formula

[0089]

[0090] Using formula (1), we can get the observation point data block I 11 and point mass data block S 11 The observation equations between

[0091] A 11 M 11 =L 11 (3)

[0092] Where:

[0093]

[0094]

[0095]

[0096] From formula (2), we can see that Only with point mass and observation points It is related to the position of the observation equations, and has nothing to do with physical properties, gravity anomalies and other parameters. It only has geometric properties but no physical properties. Therefore, the coefficient matrix of the observation equations is called A. 11 For the geometric structure. Geometric structure A ij is the coefficient matrix of the observation equation. From (2), we can see that A ij It is only related to the position of the observation point and the point mass, and has geometric properties. Solving the observation equation group (3) can obtain the point mass data block S in the first row and the first column. 11 Physical property value m st (s=s1,s1+1,…,s2, t=t1,t1+1,…,t2).

[0097] According to the point mass data block S obtained by inversion 11 Physical property value m st (s=s1,s1+1,…,s2,t=t1,t1+1,…,t2) Calculate the gravity anomaly at the observation point (p=1,2,…,N, q=1,2,…,M)

[0098]

[0099] The parameters in formula (4) are defined in the same way as in formula (1). pq Subtract Residual gravity anomaly (p=1,2,…,N, q=1,2,…,M).

[0100] Step 4: Residual Gravity Anomaly (p=1,2,…,N,q=1,2,…,M) as new observation data, using observation data block I 12 Invert the mass data block S of the point below it 12 Physical property value m st (s=s1,s1+1,…,s2,t=t2,t2+1,…,t3), and calculate the residual gravity anomaly at the observation point (p=1,2,…,N, q=1,2,…,M).

[0101] Point quality data block S 12 Physical property value m st And observation point observation data block I 12 Residual gravity anomaly The relationship between (called the observation equation) is

[0102]

[0103]

[0104] Where: s1 and s2 are S 12 Midpoint mass (or I 12 The starting and ending numbers of the latitude direction of the observation point) are t2 and t3 respectively. 12 Midpoint mass (or I 12 The starting and ending point numbers in the longitude direction of the observation point (in the middle), s1, s2, t2, t3 can be calculated according to step 2, and the definitions of other parameters are the same as those in formulas (1) and (2).

[0105] Using formula (5), we can get the observation point data block I 12 and point mass data block S 12 The observation equations between

[0106] A 12 M 12 =L 12 (7)

[0107] Where:

[0108]

[0109]

[0110]

[0111] From formula (6), we can see that the geometric structure A 12 It is only related to the point mass and the relative position of the observation points. The geometric structure A on the same latitude circle 12 and A 11 have equivalence, this property is the "geometric architecture equivalence principle", then there is a relationship A 12 =A 11 . For geometric structure A 12 After the equivalent transformation, there is no need to repeatedly calculate the observation equation coefficient matrix A 12 , saving memory consumption and improving computing efficiency.

[0112] Solving the observation equation group (7) can obtain the mass data block S of the first row and second column 12 Physical property value m st(s=s1,s1+1,…,s2, t=t2,t2+1,…,t3).

[0113] According to the point mass data block S obtained by inversion 12 Physical property value m st (s=s1,s1+1,…,s2,t=t2,t2+1,…,t3) Calculate the gravity anomaly at the observation point (p=1,2,…,N, q=1,2,…,M)

[0114]

[0115] The parameters in formula (8) are defined the same as those in formula (1). Subtract Residual gravity anomaly (p=1,2,…,N, q=1,2,…,M).

[0116] Step 5: Similar to steps 3 and 4, use the residual gravity anomaly (p=1,2,…,N,q=1,2,…,M) as new observation data, using observation data block I ij Invert the mass data block S of the point below it ij Physical property value m st (s=s i ,s i +1,…,s i+1 , t=t j ,t j +1,…,t j+1 ), according to the “geometric architecture equivalence principle” during the calculation process, there is a relationship A ij =A i1 , therefore, there is no need to repeatedly calculate the observation equation coefficient matrix A ij , which significantly saves memory consumption and improves computational efficiency. Then, the residual gravity anomaly at the observation point is calculated (p=1,2,…,N, q=1,2,…,M).

[0117] Step 6: Similar to steps 3 to 5, using residual gravity anomaly (p=1,2,…,N,q=1,2,…,M) as new observation data, using observation data block I Nr,Mc Invert the mass data block S of the point below it Nr,Mc Physical property value m st (s=s Nr ,s Nr +1,…,s Nr+1 , t=t Mc ,t Mc +1,…,tMc+1 ), according to the “geometric architecture equivalence principle” during the calculation process, there is a relationship A Nr,Mc =A Nr,1 Then, the residual gravity anomaly at the observation point is calculated (p=1,2,…,N, q=1,2,…,M).

[0118] In steps 3 to 6, according to the “geometric framework equivalence principle”, for the Mc observation equations A on the same latitude circle ij M ij =L ij (j=1,2,…,Mc), only need to calculate and save A i1 That’s it. Since the observation equation group A ij M ij =L ij The computational complexity of A is mainly determined by ij Therefore, the “geometric architecture equivalence principle” can significantly save memory consumption and improve computational efficiency. Steps 3 to 6 use the “geometric architecture equivalence principle” to calculate the geometric architecture A. ij (j=1,2,···,Mc) performs equivalent conversion so that only A needs to be calculated on the same latitude circle i1 , significantly reducing the amount of calculation and achieving rapid modeling.

[0119] Step 7: If the residual gravity is abnormal The root mean square of (p=1,2,…,N,q=1,2,…,M) is greater than a given threshold (e.g. 10 -3 mGal), then take it as observation data, repeat steps 3 to 6, and after completing the calculation in step 6, add the obtained physical property value to the physical property value calculated last time. If the residual gravity anomaly Δg Nr,Mc If the root mean square of is less than the given threshold, the iteration is terminated.

[0120] Steps 2 to 7 are the process of solving the point mass property value using the "block iteration method". Through the above steps, the global point mass model is obtained, and the data contained in the model is the location of the point mass Transitivity value m st (s=1,2,…,N, t=1,2,…,M).

[0121] Step 8: Utilize the Global Point Mass Model (s=1,2,…,N,t=1,2,…,M) Calculate the gravitational vector of the disturbance in the space outside the Earth The result of gravity field reconstruction is to obtain the disturbed gravity vector.

[0122] The global point mass model is used to calculate the disturbance gravitational vector on a certain height plane outside the Earth. The calculation points on the height plane correspond to the point mass in the vertical direction. Figure 3 As shown, the calculation point of row p and column q is O pq Indicates that the point mass data block within the effective range (determined by the window radius ρ2) is represented by Q pq Indicates (p=1,2,…,N,q=1,2,…,M). Establish calculation point O pq and point quality data block Q pq The observation equation between the points uses the mass data block Q pq Calculate O pq The perturbation gravitational vector on The relationship is

[0123]

[0124]

[0125] Where: s p 、s p+1 Q pq The starting and ending numbers of the midpoint mass in the latitude direction, t q , t q+1 Q pq The longitude direction of the midpoint mass starting point and end point serial number, there is a relationship s p =p-ρ2,s p+1 =p+ρ2,t q =q-ρ2,t q+1 =q+ρ2; G is the gravitational constant; m st is the physical property value of the mass of the point in the sth row and tth column; is the coefficient of the equation; R st is the distance from the point mass to the center of the earth (R st =Rd st ), R is the distance from the calculation point to the center of the earth; Point mass To calculation point distance Point mass and calculation points The angular distance between the sphere centers is calculated according to the following formula

[0126]

[0127]

[0128]

[0129] Use equation (9) to solve the perturbation gravitational vector When the geometry B pq The form is

[0130]

[0131] From formula (9), we can see that B pq It is only related to the point mass and the relative position of the calculation point in space, which satisfies the "geometric framework equivalence principle", that is, for M geometric frameworks B on the same latitude circle pq After equivalent conversion, we get B pq =B p1 , therefore, only B needs to be calculated and stored p1 The purpose of equivalent conversion is to reduce the amount of calculation and save storage space, and only calculate and store B p1 Matrix, which can significantly save memory consumption and improve computational efficiency.

[0132] The coordinates of the global point mass model are obtained through step 1, and the physical properties of the global point mass model are obtained through steps 2 to 7. The coordinates and physical properties together constitute the global point mass model. Step 8 is used to reconstruct the gravity field.

[0133] The present invention proposes a "gradual burial depth method" to solve the problem of poor stability or even insolvability of the solutions to the observation equations during the construction of the global point mass model. It proposes a "geometric architecture equivalence principle" to solve the problem of repeated calculation and storage of coefficient matrices. It is used for high-resolution global point mass rapid modeling and gravity field rapid reconstruction, providing a feasible way to ensure high-precision global rapid gravity fields for various types of aircraft.

[0134] The present invention also provides a gravity field reconstruction system, comprising:

[0135] The acquisition module is used to obtain the coordinates of the observation point on the earth's surface.

[0136] The point quality coordinate determination module is used to determine the point quality coordinates according to the observed point coordinates.

[0137] The equal division module is used to equally divide the point quality coordinates and the observation point coordinates to obtain observation point data blocks and point quality data blocks.

[0138] An inversion module is used to use the observation point data block to invert the physical property value of the point quality data block corresponding to the observation point data block.

[0139] The residual gravity anomaly determination module is used to determine the residual gravity anomaly of the observation point data block according to the physical property values ​​of the point mass data block.

[0140] The judgment module is used to judge whether the root mean square of the residual gravity anomaly is less than a set threshold and obtain a judgment result.

[0141] The updating and returning module is used to take the residual gravity anomaly as the observation data of the observation point data block and return it to the inversion module if the judgment result is no.

[0142] The global point mass model determination module is configured to determine a global point mass model according to the physical property values ​​of the point mass data block and the position of the point mass in the point mass data block if the judgment result is yes.

[0143] The module for determining the gravitational vector of the disturbance in the earth's external space is used to calculate the gravitational vector of the disturbance in the earth's external space according to the global point mass model; the gravitational vector of the disturbance in the earth's external space is used to reconstruct the gravity field.

[0144] In practical applications, the bisection module specifically includes:

[0145] The point quality coordinate dividing unit is used to divide the point quality coordinates equally along the longitude direction and the latitude direction respectively to obtain point quality data blocks.

[0146] The observation point coordinate dividing unit is used to divide the observation point coordinates equally along the longitude direction and the latitude direction respectively to obtain observation point data blocks.

[0147] In practical applications, the residual gravity anomaly determination module specifically includes:

[0148] The observation equation determination unit is used to determine the observation equation according to the physical property values ​​of the point mass data block and the gravity anomaly observation value of the observation point data block.

[0149] The residual gravity anomaly determination unit is used to determine the residual gravity anomaly of the measuring point data block according to the physical property values ​​of the point mass data block and the gravity anomaly observation value of the measuring point data block using the observation equation.

[0150] The present invention further provides an electronic device, comprising:

[0151] One or more processors.

[0152] A storage device having one or more programs stored thereon.

[0153] When the one or more programs are executed by the one or more processors, the one or more processors are enabled to implement any one of the methods described above.

[0154] The present invention also provides a computer storage medium having a computer program stored thereon, wherein the computer program implements any one of the methods described above when executed by a processor.

[0155] The technology provided by this invention enables the rapid construction of a global point mass model and the rapid reconstruction of Earth's gravity field. Compared with conventional methods, it improves the stability of the solution to the observation equations, eliminating the need for repeated calculation and storage of coefficient matrices. This overcomes the bottlenecks of rapid high-resolution global point mass modeling and rapid gravity field reconstruction, which often suffer from poor solution stability (or even insolvability) and extremely low computational efficiency. This provides a feasible approach for ensuring high-precision, rapid global gravity field measurements for various types of aircraft. This technology is not limited by data resolution and is applicable to gravity field reconstruction in any region, demonstrating its high practicality.

[0156] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0157] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A gravity field reconstruction method, characterized in that: include: Get the coordinates of the observation point on the earth's surface; determining point mass coordinates based on the observed point coordinates; Dividing the point quality coordinates and the observation point coordinates equally to obtain observation point data blocks and point quality data blocks; Inverting the physical property value of the point mass data block corresponding to the observation point data block using the observation point data block; determining a residual gravity anomaly of the observation point data block based on the physical property values ​​of the point mass data block; Determining whether the root mean square of the residual gravity anomaly is less than a set threshold, and obtaining a determination result; If the judgment result is no, the residual gravity anomaly is used as the observation data of the observation point data block, and the process returns to the step of "using the observation point data block to invert the physical property value of the point mass data block corresponding to the observation point data block"; If the judgment result is yes, determining a global point mass model according to the physical property values ​​of the point mass data block and the positions of the point masses in the point mass data block; The gravitational vector of the disturbance in the Earth's external space is calculated according to the global point mass model; the gravitational vector of the disturbance in the Earth's external space is used to reconstruct the gravity field.

2. The gravity field reconstruction method according to claim 1, characterized in that: The step of equally dividing the point quality coordinates and the observation point coordinates to obtain an observation point data block and a point quality data block specifically includes: Dividing the point quality coordinates equally along the longitude and latitude directions to obtain point quality data blocks; The observation point coordinates are equally divided along the longitude and latitude directions to obtain observation point data blocks.

3. The gravity field reconstruction method according to claim 1, characterized in that: The determining of the residual gravity anomaly of the observation point data block according to the physical property value of the point mass data block specifically includes: Determining an observation equation based on the physical property values ​​of the point mass data block and the gravity anomaly observation value of the observation point data block; The residual gravity anomaly of the measuring point data block is determined according to the physical property values ​​of the point mass data block and the gravity anomaly observation value of the measuring point data block using the observation equation.

4. The gravity field reconstruction method according to claim 1, characterized in that: The global point mass model includes the position of the point mass data block and the physical property value of the point mass data block.

5. The gravity field reconstruction method according to claim 1, characterized in that: The expression of the gravitational force vector of the external space disturbance of the Earth is: in, To calculate the radial component of the point perturbation gravity, To calculate the latitude component of the gravity of the point disturbance, To calculate the longitudinal component of the point disturbance gravity, s p Point quality data block Q pq The starting point number in the latitude direction of the midpoint mass, s p+1 Point quality data block Q pq The end point number in the latitude direction of the midpoint mass, t q Point quality data block Q pq The starting point number in the longitude direction of the midpoint mass, t q+1 Point quality data block Q pq The endpoint number in the longitude direction of the midpoint mass, G is the gravitational constant, m st is the physical property value of the mass of the point in the sth row and tth column, is the first coefficient of the equation, is the second coefficient of the equation, is the third coefficient of the equation, R st is the distance from the point mass to the center of the Earth; Point mass To calculation point distance; Point mass and calculation points The angular distance between the sphere centers, is the azimuth, is the latitude coordinate of the point mass, λ t is the longitude coordinate of the point mass, r pq is the geocentric radius of the calculation point, is the latitude coordinate of the calculation point, λ q The longitude coordinate of the calculation point.

6. A gravity field reconstruction system, characterized in that: include: An acquisition module is used to obtain the coordinates of observation points on the earth's surface; a point mass coordinate determination module, configured to determine the point mass coordinates according to the observed point coordinates; an equal division module, configured to equally divide the point quality coordinates and the observation point coordinates to obtain observation point data blocks and point quality data blocks; an inversion module, configured to use the observation point data block to invert the physical property value of the point mass data block corresponding to the observation point data block; a residual gravity anomaly determination module, configured to determine the residual gravity anomaly of the observation point data block based on the physical property values ​​of the point mass data block; a judgment module, configured to judge whether the root mean square of the residual gravity anomaly is less than a set threshold value, and obtain a judgment result; an updating and returning module, configured to use the residual gravity anomaly as the observation data of the observation point data block and return the result to the inversion module if the judgment result is negative; a global point mass model determination module, configured to determine a global point mass model according to the physical property values ​​of the point mass data block and the position of the point mass in the point mass data block if the judgment result is yes; The module for determining the gravitational vector of the disturbance in the earth's external space is used to calculate the gravitational vector of the disturbance in the earth's external space according to the global point mass model; the gravitational vector of the disturbance in the earth's external space is used to reconstruct the gravity field.

7. The gravity field reconstruction system according to claim 6, characterized in that: The bisection module specifically includes: a point quality coordinate dividing unit, configured to divide the point quality coordinates equally along the longitude and latitude directions to obtain point quality data blocks; The observation point coordinate dividing unit is used to divide the observation point coordinates equally along the longitude direction and the latitude direction respectively to obtain observation point data blocks.

8. The gravity field reconstruction system according to claim 6, characterized in that: The residual gravity anomaly determination module specifically includes: an observation equation determining unit, configured to determine an observation equation based on the physical property values ​​of the point mass data block and the gravity anomaly observation value of the observation point data block; The residual gravity anomaly determination unit is used to determine the residual gravity anomaly of the measuring point data block according to the physical property values ​​of the point mass data block and the gravity anomaly observation value of the measuring point data block using the observation equation.

9. An electronic device, characterized in that: include: one or more processors; a storage device having one or more programs stored thereon; When the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the method according to any one of claims 1 to 5.

10. A computer storage medium, characterized in that A computer program is stored thereon, wherein when the computer program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.

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