Method and device for converting user precise single point positioning result into CGCS2000 coordinates

Abstract

The application discloses a method for converting user precise point positioning results into CGCS2000 coordinates, comprising the following steps: based on the precise GNSS satellite orbit and clock error products provided by IGS, performing GNSS precise point positioning data processing on a user survey station and at least three IGS survey stations respectively to obtain respective precise point positioning results; according to the precise point positioning results of the IGS survey stations at the same ephemeris and the corresponding CGCS2000 coordinates, constructing an indirect adjustment error equation to solve the conversion parameters of the conversion of the precise point positioning results into the CGCS2000 coordinate system; and based on the conversion parameters, converting the precise point positioning results of the user survey station to obtain the CGCS2000 coordinates of the user survey station. The application provides a prerequisite basis for the high-precision measurement engineering coordinate conversion of precise point positioning results, so as to enhance the usability of the precise point positioning technology in actual engineering projects.

Description

Technical Field

[0001] This invention relates to the technical fields of satellite navigation and positioning, geodesy and engineering surveying, and in particular to a method and apparatus for converting user precise single-point positioning results into CGCS2000 coordinates. Background Technology

[0002] GNSS precise point positioning refers to a method in which a user uses the carrier phase and code pseudo-observations of a GNSS receiver, utilizes high-precision satellite orbit and clock error products, and eliminates the influence of errors related to the satellite end, signal propagation path, and receiver end, such as antenna position deviation, tropospheric delay, ionospheric delay, and phase entanglement, through parameter estimation, model correction, and other methods, on positioning, thereby achieving high-precision positioning.

[0003] Precise point positioning can achieve centimeter or even millimeter-level accuracy, possessing unique application value in many fields such as large-scale mobile surveying, precise time synchronization, low-Earth orbit satellite orbit determination, atmospheric science, and geodynamics. However, it has not been fully utilized in practical civil engineering. One major reason is that its results are determined by satellite orbit and clock bias products provided by IGS, lacking a precise reference coordinate framework. In my country, the China Geodetic Coordinate System 2000 (CGCS2000) is used for construction control surveying in engineering projects. This coordinate system encompasses surveying results from various periods in my country and is based on the ITRF97 definition at epoch 2000.0. Precise point positioning results need to be converted to the CGCS2000 coordinate system to be consistent with previous surveying results and applied in engineering projects, which presents the following problems:

[0004] 1) The release of IGS satellite orbit and clock products is delayed and lacks a clear corresponding epoch, making it difficult to determine the epoch conversion parameters;

[0005] 2) Multiple IGS analysis centers release satellite orbit and clock bias products, and the time and coordinate references used for their calculations differ, resulting in inconsistencies in the epochs at which the calculation results are obtained using satellite orbit and clock bias products from different sources.

[0006] 3) Traditional ITRF framework conversion methods require obtaining station velocity values. The velocity field in my country is relatively complex, and the velocity at the point changes with time and geographical location. In addition, the conversion time span is long. Using velocity for epoch conversion requires additional velocity field data support, and velocity field errors are easily accumulated and amplified. Summary of the Invention

[0007] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0008] In view of the problems existing in the above and / or existing precision single-point positioning in practical engineering applications, the present invention is proposed.

[0009] Therefore, the problem to be solved by this invention is how to convert the precise single-point positioning results to the CGCS2000 coordinate system.

[0010] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0011] In a first aspect, embodiments of the present invention provide a method for converting user precise single-point positioning results into CGCS2000 coordinates, comprising,

[0012] Based on the precise GNSS satellite orbit and clock difference products provided by IGS, GNSS precise point positioning data processing is performed on the user station and at least 3 IGS stations respectively to obtain their respective precise point positioning results;

[0013] Based on the precise single-point positioning results of the IGS station at the same epoch and their corresponding CGCS2000 coordinates, an indirect adjustment error equation is constructed, and the transformation parameters for converting the precise single-point positioning results to the CGCS2000 coordinate system are solved.

[0014] Based on the transformation parameters, the precise single-point positioning results of the user station are transformed to obtain the CGCS2000 coordinates of the user station.

[0015] As a preferred embodiment of the method for converting user precise single-point positioning results into CGCS2000 coordinates as described in this invention, the observation dates of at least three IGS stations, the observation date of the user station, and the dates of IGS satellite orbit and clock difference products must be consistent, and the satellite orbit and clock difference products must be products from the same IGS analysis center.

[0016] As a preferred embodiment of the method for converting user precise single-point positioning results to CGCS2000 coordinates according to the present invention, the step of constructing an indirect adjustment error equation based on the precise single-point positioning results of the IGS station at the same epoch and their corresponding CGCS2000 coordinates, and solving for the transformation parameters for converting the precise single-point positioning results to the CGCS2000 coordinate system includes:

[0017] Using the velocity and coordinate parameters officially released by ITRF, the coordinates of the IGS station at 2000 epochs under the ITRF97 framework were calculated, and the CGCS2000 coordinates of the IGS station were obtained.

[0018] Based on the precise single-point positioning results of the IGS station and its CGCS2000 coordinates, the transformation formula is linearized to form a set of error equations for indirect adjustment, and the transformation parameters for transforming the precise single-point positioning results to the CGCS2000 coordinate system are solved.

[0019] As a preferred embodiment of the method for converting user precise single-point positioning results to CGCS2000 coordinates according to the present invention, the step of solving the transformation parameters for converting precise single-point positioning results to the CGCS2000 coordinate system includes:

[0020] The coordinate transformation parameters are calculated using an iterative method. The approximate value of each transformation parameter is set to 0. An error equation is constructed to solve for the correction of the approximate value. The corrected approximate value is then judged.

[0021] If the absolute value of the correction exceeds the limit, the error equation is reconstructed using the corrected approximation. The calculation is iterated until the correction is less than the limit, and then the approximation at this point is output as the solution result of the parameter.

[0022] If the absolute value of the correction is less than the limit, the approximate value at this time will be directly output as the solution result of the parameter.

[0023] As a preferred embodiment of the method for converting user precise single-point positioning results to CGCS2000 coordinates according to the present invention, the step of converting the user station's precise single-point positioning results according to the calculated conversion parameters to obtain the user station's CGCS2000 coordinates includes:

[0024] The transformation parameters include 3 translation parameters, 1 scaling parameter, and 3 rotation parameters;

[0025] A seven-parameter conversion model is constructed based on the conversion parameters to convert the precise single-point positioning results and obtain the CGCS2000 coordinates of the user station.

[0026] As a preferred embodiment of the method for converting user precise single-point positioning results into CGCS2000 coordinates according to the present invention, the step of linearizing the conversion formula to form a set of error equations for indirect adjustment includes,

[0027] The set of error equations for the i-th IGS station is as follows:

[0028]

[0029] in, The correction value for the observed value, (x′) i ,y′ i ,z′ i (x) represents the coordinates before transformation, and (x) represents the coordinates before transformation. i ,y i ,z i (x0, y0, z0) represents the transformed coordinates, (x0, y0, z0) represents the translation, k represents the scale, α, β, γ represent the rotation angles around the x-axis, y-axis, and z-axis, respectively, and R represents the coordinates. α ,R β ,R γ Let be the rotation matrix corresponding to α, β, γ;

[0030] Approximate values ​​for the seven transformation parameters k 0 α 0 β 0 γ 0 Linearization yields:

[0031]

[0032] in, These are the correction values ​​for the seven transformation parameters;

[0033] Among them, the constant term l i for:

[0034]

[0035] remember

[0036]

[0037]

[0038] Then we can get:

[0039]

[0040] If there are n IGS stations in total, then their error equations can be solved simultaneously as follows:

[0041]

[0042] Where V is the correction value of the observation, B is the design matrix, and L is the constant term, this equation is the basic form of the indirect adjustment error equation.

[0043] As a preferred embodiment of the method for converting user precise single-point positioning results into CGCS2000 coordinates according to the present invention, wherein: the calculation of coordinate transformation parameters using an iterative method includes,

[0044] In the j-th iteration, the approximate value of the transformation parameter is denoted as:

[0045]

[0046] The initial values ​​of the approximate transformation parameters are set to 0. Assuming that all observations are equally weighted, the corrections to the parameters are as follows, according to the indirect adjustment method equation:

[0047]

[0048] Add the correction to the approximate value of the parameter to obtain the new approximate value:

[0049]

[0050] Secondly, embodiments of the present invention provide a system for converting user precise single-point positioning results into CGCS2000 coordinates, comprising:

[0051] The data processing module is used to perform GNSS precise point positioning data processing on the user station and at least three IGS stations based on the precise GNSS satellite orbit and clock difference products provided by IGS, and obtain their respective precise point positioning results.

[0052] The parameter calculation module is used to construct an indirect adjustment error equation based on the precise single-point positioning results of the IGS station at the same epoch and its corresponding CGCS2000 coordinates, and to solve the transformation parameters for converting the precise single-point positioning results to the CGCS2000 coordinate system.

[0053] The coordinate transformation module is used to transform the precise single-point positioning results of the user station based on the transformation parameters to obtain the CGCS2000 coordinates of the user station.

[0054] Thirdly, embodiments of the present invention provide a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement any step of the above-described method.

[0055] Fourthly, embodiments of the present invention provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements any step of the above-described method.

[0056] The beneficial effects of this invention are as follows: Addressing the problems of difficulty and low accuracy in converting user precise single-point positioning results to the CGCS2000 coordinate system, this invention proposes a method for converting user precise single-point positioning results to CGCS2000 coordinates. This reduces the conversion error caused by epoch and velocity uncertainties in the precise single-point positioning results, improves the accuracy of the converted CGCS2000 coordinates, and enables the precise single-point positioning results to be applied in engineering operations, thus expanding the application scope of precise single-point positioning technology. Attached Figure Description

[0057] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0058] Figure 1 A flowchart illustrating the method for converting precise single-point positioning results for users into CGCS2000 coordinates.

[0059] Figure 2 A graph showing the conversion deviation results of the method for converting precise single-point positioning results to CGCS2000 coordinates. Detailed Implementation

[0060] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0061] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0062] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0063] This invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of this invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not be construed as limiting the scope of protection of this invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0064] Furthermore, in the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In addition, the terms "first," "second," or "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0065] Unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" in this invention should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; similarly, they can refer to mechanical connections, electrical connections, or direct connections, or indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0066] Example 1

[0067] Reference Figure 1 This is the first embodiment of the present invention, which provides a method for converting user precise single-point positioning results into CGCS2000 coordinates, including:

[0068] S100: Based on the precise GNSS satellite orbit and clock error products provided by IGS (International GNSS Service), perform precise point positioning data processing on the user station and at least 3 IGS stations respectively to obtain their respective precise point positioning results.

[0069] It should be noted that, based on the observation period of the station, the final precise ephemeris product provided by the IGS GNSS service for the corresponding date is selected to perform post-processing precise point positioning on the user station and the selected IGS station, and obtain their respective precise point positioning results.

[0070] It should be noted that the observation dates of at least three IGS stations, the user observation dates, and the dates of IGS satellite orbits and clock bias products must be consistent, and the satellite orbits and clock bias products must be products from the same IGS analysis center.

[0071] S200: Based on the precise single-point positioning results of the IGS station at the same epoch and their corresponding CGCS2000 coordinates, the transformation parameters for converting the precise single-point positioning results to the CGCS2000 coordinate system are jointly calculated using the indirect adjustment method.

[0072] It should be noted that at least three IGS stations performed CGCS2000 coordinate calculations within the ITRF97 framework, that is, using the speed and coordinate parameters officially released by ITRF to calculate the coordinates of the IGS stations at 2000 epochs within the ITRF97 framework.

[0073] It should be noted that, based on the precise single-point positioning results of the IGS station and its CGCS2000 coordinates, the transformation formula is linearized to form a set of error equations for indirect adjustment.

[0074] Specifically, the coordinate transformation parameters are calculated using an iterative method. The approximate value of each transformation parameter is set to 0. An error equation is constructed to calculate the correction value of the approximate value. The corrected approximate value is then judged. If the absolute value of the correction value exceeds the limit, the error equation is reconstructed using the corrected approximate value. The calculation is iterated until the correction value is less than the limit, and the approximate value at this point is output as the result of the parameter calculation. If the absolute value of the correction value is less than the limit, the approximate value at this point is directly output as the result of the parameter calculation.

[0075] It should be noted that the set of error equations for the i-th IGS station is as follows:

[0076]

[0077] in, The correction value for the observed value, (x′) i ,y′ i ,z′ i (x) represents the coordinates before transformation, and (x) represents the coordinates before transformation. i ,y i ,z i (x0, y0, z0) represents the transformed coordinates, (x0, y0, z0) represents the translation, k represents the scale, α, β, γ represent the rotation angles around the x-axis, y-axis, and z-axis, respectively, and R represents the coordinates. α ,R β ,R γ Let be the rotation matrix corresponding to α, β, γ.

[0078] Approximate values ​​for the seven transformation parameters k 0 α 0 β 0 γ 0 Linearizing the above equation, we get:

[0079]

[0080] in, These are the corrections for the seven transformation parameters, and the constant term l. i for:

[0081]

[0082] remember

[0083]

[0084]

[0085] Then equation (2) can also be written as:

[0086]

[0087] If there are n IGS stations in total, then their error equations can be solved simultaneously as follows:

[0088]

[0089] Where V is the correction value of the observation, B is the design matrix, and L is the constant term, this equation is the basic form of the indirect adjustment error equation.

[0090] Furthermore, the transformation parameters are solved using an iterative method. In the j-th iteration, the approximate value of the transformation parameters is denoted as:

[0091]

[0092] The initial values ​​of the approximate transformation parameters are set to 0. Assuming that all observations are equally weighted, the corrections to the parameters are as follows, according to the indirect adjustment method equation:

[0093]

[0094] Add the correction to the approximate value of the parameter to obtain the new approximate value:

[0095]

[0096] S300: Based on the calculated transformation parameters, the precise single-point positioning results of the user station are transformed to obtain the CGCS2000 coordinates of the user station.

[0097] It should be noted that the transformation parameters include 3 translation parameters, 1 scale parameter, and 3 rotation parameters. Based on the above parameters, a seven-parameter transformation model is constructed to transform the precise single-point positioning results and obtain the CGCS2000 coordinates of the point to be determined.

[0098] Furthermore, this embodiment also provides a system for converting user precise single-point positioning results into CGCS2000 coordinates, including:

[0099] The data processing module is used to perform GNSS precise point positioning data processing on the user station and at least three IGS stations based on the precise GNSS satellite orbit and clock difference products provided by IGS, and obtain their respective precise point positioning results.

[0100] The parameter calculation module is used to construct an indirect adjustment error equation based on the precise single-point positioning results of the IGS station at the same epoch and its corresponding CGCS2000 coordinates, and to solve the transformation parameters for converting the precise single-point positioning results to the CGCS2000 coordinate system.

[0101] The coordinate transformation module is used to transform the precise single-point positioning results of the user station based on the transformation parameters to obtain the CGCS2000 coordinates of the user station.

[0102] This embodiment also provides a computer device applicable to the method of converting user precise single-point positioning results into CGCS2000 coordinates, including:

[0103] The system includes a memory and a processor. The memory stores computer-executable instructions, and the processor executes these instructions to implement the method described in the above embodiments for converting user precise single-point positioning results into CGCS2000 coordinates.

[0104] The computer device can be a terminal, comprising a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device's casing, or an external keyboard, touchpad, or mouse.

[0105] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, it implements the method proposed in the above embodiment for converting user precise single-point positioning results into CGCS2000 coordinates.

[0106] The storage medium proposed in this embodiment and the data storage method proposed in the above embodiments belong to the same inventive concept. Technical details not described in detail in this embodiment can be found in the above embodiments, and this embodiment has the same beneficial effects as the above embodiments.

[0107] Example 2

[0108] Reference Figure 2This is the second embodiment of the present invention, which provides a method for converting user precise single-point positioning results into CGCS2000 coordinates. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through experiments.

[0109] Because the conversion method provided by the ITRF official website requires explicit knowledge of the epoch and velocity of the conversion point before and after the conversion, and the conversion accuracy is relatively low, the innovation of this invention lies in accurately converting precise single-point positioning results to CGCS2000 coordinates even when the epoch is unclear and the velocity field is unknown. Compared with conventional methods, this method requires less data, is simpler to calculate, and has higher conversion accuracy. The main implementation method is to incorporate the positional changes caused by the unclear epoch into the conversion parameters, thereby achieving high-precision coordinate conversion.

[0110] This experiment selected data from five IGS stations within my country, which are also GNSS frame points in the ITRF framework. These stations are: BJFS (Fangshan, Beijing), SHAO (Sheshan, Shanghai), BJNM (Miyun, Beijing), JFNG (Jiufeng, Wuhan), and CHAN (Changchun, Jilin). The experiment involved converting the precise single-point positioning results from GPS on May 7, 2018, into CGCS2000 coordinate transformation parameters. The specific steps are as follows:

[0111] S100: Obtain observation files, precise orbits, and precise clock difference products covering the entire day of May 7, 2018 (from 22:45 the previous day to 1:15 the following day) from the IGS official website, perform post-processing precise single-point positioning on the five IGS stations, and obtain their precise single-point positioning results; obtain the coordinates of the IGS stations at epoch 2000.0 of the ITRF97 frame from the ITRF official website, which are the corresponding CGCS2000 coordinates of the stations.

[0112] S200: Group the five IGS stations, using the JFNG station as the user station to verify the coordinate transformation effect of the user station; use the BJFS, SHAO, BJNM, and CHAN stations to calculate the coordinate transformation parameters.

[0113] It should be noted that the precise single-point positioning results from four stations were used in conjunction with CGCS2000 coordinates to construct an indirect adjustment error equation and iteratively solve for the parameters, then the coordinate transformation residuals were statistically analyzed. The threshold for convergence of the iteration was considered to be: the absolute value of the coordinate parameter correction was less than 10. -9 m, the absolute value of the scale parameter correction is less than 10. -8 The absolute value of the angle parameter correction is less than 10. - 9 rad.

[0114] S300: Use the obtained transformation parameters to transform the precise single-point positioning results of the user station, and compare the transformed coordinates with its CGCS2000 coordinates. Analyze the accuracy of the coordinate transformation method of converting the precise single-point positioning results of this user to CGCS2000 coordinates based on the difference, and evaluate its coordinate transformation effect and its application scope.

[0115] The coordinate transformation results of five IGS stations in my country using this invention are shown in the figure below. Figure 2 As shown, the vertical axis represents the transformation residual, which is the difference between the CGCS2000 coordinates obtained by transforming the precise single-point positioning results using this invention and their actual CGCS2000 coordinates. The data on the horizontal axis is divided into five groups, each group representing the transformation residual of a single station projected onto the X, Y, and Z directions of the geocentric coordinate system. It can be seen that the transformation accuracy of this invention can reach the centimeter or even millimeter level, compensating for the large transformation errors caused by the uncertainty of the epoch and velocity in the precise single-point positioning results, and the low transformation accuracy of the CGCS2000 coordinates.

[0116] In the above example, the transformation parameters of a method for converting user precise single-point positioning results to CGCS2000 coordinates are calculated. The position changes caused by the epoch are incorporated into the transformation parameters to quickly determine the transformation parameters for converting precise single-point positioning results to the CGCS2000 coordinate system, reduce the error of coordinate transformation, and thus achieve high-precision coordinate transformation.

[0117] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for converting user precise single-point positioning results into CGCS2000 coordinates, characterized in that: include, Based on the precise GNSS satellite orbit and clock difference products provided by IGS, GNSS precise point positioning data processing is performed on the user station and at least 3 IGS stations respectively to obtain their respective precise point positioning results; Based on the precise single-point positioning results of the IGS station at the same epoch and their corresponding CGCS2000 coordinates, an indirect adjustment error equation is constructed, and the transformation parameters for converting the precise single-point positioning results to the CGCS2000 coordinate system are solved. Based on the transformation parameters, the precise single-point positioning results of the user station are transformed to obtain the CGCS2000 coordinates of the user station.

2. The method for converting user precise single-point positioning results into CGCS2000 coordinates as described in claim 1, characterized in that: The observation dates of at least three IGS stations, the observation dates of user stations, and the dates of IGS satellite orbits and clock bias products must be consistent, and the satellite orbits and clock bias products must be products from the same IGS analysis center.

3. The method for converting user precise single-point positioning results into CGCS2000 coordinates as described in claim 2, characterized in that: The step of constructing an indirect adjustment error equation based on the precise single-point positioning results of the IGS station at the same epoch and their corresponding CGCS2000 coordinates, and solving for the transformation parameters to convert the precise single-point positioning results to the CGCS2000 coordinate system, includes: Using the velocity and coordinate parameters officially released by ITRF, the coordinates of the IGS station at 2000 epochs under the ITRF97 framework were calculated, and the CGCS2000 coordinates of the IGS station were obtained. Based on the precise single-point positioning results of the IGS station and its CGCS2000 coordinates, the transformation formula is linearized to form a set of error equations for indirect adjustment, and the transformation parameters for transforming the precise single-point positioning results to the CGCS2000 coordinate system are solved.

4. The method for converting user precise single-point positioning results into CGCS2000 coordinates as described in claim 3, characterized in that: The process of solving for the transformation parameters when converting the precise single-point positioning results to the CGCS2000 coordinate system includes: The coordinate transformation parameters are calculated using an iterative method. The approximate value of each transformation parameter is set to 0. An error equation is constructed to solve for the correction of the approximate value. The corrected approximate value is then judged. If the absolute value of the correction exceeds the limit, the error equation is reconstructed using the corrected approximation. The calculation is iterated until the correction is less than the limit, and then the approximation at this point is output as the solution result of the parameter. If the absolute value of the correction is less than the limit, the approximate value at this time will be directly output as the solution result of the parameter.

5. The method for converting user precise single-point positioning results into CGCS2000 coordinates as described in claim 4, characterized in that: The process of converting the precise single-point positioning results of the user station based on the conversion parameters to obtain the CGCS2000 coordinates of the user station includes: The transformation parameters include 3 translation parameters, 1 scaling parameter, and 3 rotation parameters; Based on the obtained conversion parameters, a seven-parameter conversion model is constructed to convert the precise single-point positioning results and obtain the CGCS2000 coordinates of the user station.

6. The method for converting user precise single-point positioning results into CGCS2000 coordinates as described in claim 5, characterized in that: The process of linearizing the transformation formula to form the error equation set for indirect adjustment includes: The set of error equations for the i-th IGS station is as follows: in, These are the correction values ​​for the observed values. The coordinates before transformation The transformed coordinates ， The translation amount, As a scale, These represent the angles of rotation about the x-axis, y-axis, and z-axis, respectively. for The corresponding rotation matrix; Approximate values ​​for the seven transformation parameters 、 、 、 、 、 、 Linearization yields: in, , , , , , , These are the correction values ​​for the seven transformation parameters; Among them, the constant term for: remember: Then we can get: If there is a total For each IGS station, the error equations can be solved simultaneously as follows: in, These are the correction values ​​for the observed values. To design the matrix, The constant term is the basic form of the indirect adjustment error equation.

7. The method for converting user precise single-point positioning results into CGCS2000 coordinates as described in claim 6, characterized in that: The calculation of coordinate transformation parameters using an iterative method includes, In the j-th iteration, the approximate value of the transformation parameter is denoted as: The initial values ​​of the approximate transformation parameters are set to 0. Assuming that all observations are equally weighted, the corrections to the parameters are as follows, according to the indirect adjustment method equation: Add the correction to the approximate value of the parameter to obtain the new approximate value: 。 8. A system for converting user precise single-point positioning results into CGCS2000 coordinates, based on the method for converting user precise single-point positioning results into CGCS2000 coordinates according to any one of claims 1 to 7, characterized in that: include, The data processing module is used to perform GNSS precise point positioning data processing on the user station and at least three IGS stations based on the precise GNSS satellite orbit and clock difference products provided by IGS, and obtain their respective precise point positioning results. The parameter calculation module is used to construct an indirect adjustment error equation based on the precise single-point positioning results of the IGS station at the same epoch and its corresponding CGCS2000 coordinates, and to solve the transformation parameters for converting the precise single-point positioning results to the CGCS2000 coordinate system. The coordinate transformation module is used to transform the precise single-point positioning results of the user station based on the transformation parameters to obtain the CGCS2000 coordinates of the user station.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

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