High-precision positioning method, computing device and computer-readable medium

Abstract

The present invention relates to a high-precision positioning method, a computing device and a computer-readable medium based on inter-epoch differences. The high-precision positioning method comprises: calculating an observation parameter vector according to the amount of change in observation values ​​between adjacent epochs, wherein the amount of change in observation values ​​between adjacent epochs is the difference in observation values ​​between adjacent epochs, calculating the residual of the observation value of the current epoch according to the amount of change in observation values ​​between adjacent epochs, the amount of change in satellite-to-earth distance or the amount of change in satellite-to-earth distance change rate between adjacent epochs and the observation parameter vector, judging whether there is a gross error in the observation value according to the residual, and if so, calculating the observation parameter vector again based on the remaining observation values ​​after eliminating the observation value with the largest gross error and subsequent operations until the unit weighted mean error of all remaining observation values ​​meets the requirements. In this way, pseudorange observation values, Doppler observation values ​​and carrier observation values ​​with gross errors can be effectively eliminated, thereby improving the precision and accuracy of the RTK high-precision positioning method.

Description

Technical Field

[0001] This invention relates to the field of navigation, and more particularly to a high-precision positioning algorithm, computing device, and computer-readable medium based on interepoch difference. Background Technology

[0002] Global Navigation Satellite System (GNSS) technology has wide applications in military, political, and economic fields. RTK (Real-Time Kinematic) is a widely used GNSS technology that utilizes real-time satellite observation data for dynamic relative positioning. In short-baseline scenarios, by establishing a double-difference relative positioning model based on observation equations, not only can receiver and satellite clock errors be eliminated, but also spatially correlated errors such as ionospheric and tropospheric delays can be significantly reduced, while preserving the integer characteristics of ambiguities.

[0003] With the changing user scenarios, the challenges to RTK technology are increasing. When there is interference in the user's surrounding environment that affects the line-of-sight transmission of electromagnetic waves, such as trees, buildings, or water surfaces, it will have a certain impact on the transmission of electromagnetic waves. External interference causes the receiver to track electromagnetic wave signals transmitted from the satellite segment with different kinds of interference. These interferences manifest at the observation level as pseudorange, gross errors in Doppler observations, and cycle slips in carrier observations. When there are interference factors in the observations, it will inevitably directly reduce the accuracy and precision of the RTK method.

[0004] Therefore, it is necessary to propose a solution to the above problems. Summary of the Invention

[0005] The purpose of this invention is to propose a high-precision positioning algorithm, computing device, and computer-readable medium based on interepoch difference, which can effectively eliminate pseudorange observations with gross errors, Doppler observations, and carrier observations with cycle slips, thereby improving the accuracy and precision of the RTK high-precision positioning method.

[0006] To address the aforementioned technical problems, according to one aspect of the present invention, a high-precision positioning method is proposed, comprising: calculating a pseudorange observation parameter vector based on the pseudorange change between adjacent epochs, wherein the pseudorange change between adjacent epochs is the difference between pseudorange observation values ​​between adjacent epochs; calculating the pseudorange residual of the pseudorange observation value at the current epoch based on the pseudorange change between adjacent epochs, the satellite-to-Earth distance change between adjacent epochs, and the pseudorange observation parameter vector; determining whether there is a gross error in the pseudorange observation value based on the pseudorange residual; if so, determining whether the unit weight mean square error of all current pseudorange observation values ​​meets the requirements; if not, discarding the pseudorange observation with the largest gross error. After the initial pseudorange observation, the pseudorange observation parameter vector and subsequent calculations are recalculated based on the remaining pseudorange observations until the unit weight mean square error of all remaining pseudorange observations meets the requirements. The Doppler observation parameter vector is calculated based on the Doppler variation between adjacent epochs, where the Doppler variation between adjacent epochs is the difference between the Doppler observations of adjacent epochs. The Doppler residual of the current epoch's Doppler observations is calculated based on the Doppler variation between adjacent epochs, the variation rate of the satellite-Earth distance between adjacent epochs, and the Doppler observation parameter vector. The presence of gross errors in the Doppler observations is determined based on the Doppler residuals. If gross errors exist, all current Doppler observations are then evaluated. If the unit weighted mean square error of the Doppler observations does not meet the requirements, the Doppler observations with the largest gross errors are removed, and the Doppler observation parameter vector and subsequent calculations are recalculated based on the remaining Doppler observations until the unit weighted mean square error of all remaining Doppler observations meets the requirements. The carrier observation parameter vector is calculated based on the carrier variation between adjacent epochs, where the carrier variation between adjacent epochs is the difference between the carrier observations between adjacent epochs. The carrier residual of the current epoch's carrier observation is calculated based on the carrier variation between adjacent epochs, the satellite-to-Earth distance variation between adjacent epochs, and the carrier observation parameter vector. The carrier observation is then judged based on the carrier residual. If a cycle slip exists in the measurement, and if so, it is determined whether the unit weight mean square error of all current carrier observations meets the requirements. If not, the carrier observation with the largest cycle slip is removed, and the carrier observation parameter vector and subsequent operations are recalculated based on the remaining carrier observations until the unit weight mean square error of all remaining carrier observations meets the requirements. The pseudorange observation parameter vector includes the position corrections for the three axes and the clock rate variation between adjacent epochs. The Doppler observation parameter vector includes the velocity corrections for the three axes and the clock rate variation between adjacent epochs. The carrier observation parameter vector includes the position corrections for the three axes and the clock rate variation between adjacent epochs.

[0007] According to another aspect of the present invention, the present invention provides a high-precision positioning method based on inter-epoch difference, comprising: calculating an observation parameter vector based on the change in observation values ​​between adjacent epochs, wherein the change in observation values ​​between adjacent epochs is the difference between the observation values ​​between adjacent epochs; calculating the residual of the observation values ​​at the current epoch based on the change in observation values ​​between adjacent epochs, the change in satellite-to-Ground distance or the change in the rate of change of satellite-to-Ground distance between adjacent epochs, and the observation parameter vector; determining whether there are gross errors or cycle slips in the observation values ​​based on the residuals; if so, determining whether the unit weight mean square error of all current observation values ​​meets the requirements; if not, removing the observation value with the largest gross error or cycle slip, and recalculating the observation parameter vector and subsequent operations based on the remaining observation values ​​until the unit weight mean square error of all remaining observation values ​​meets the requirements; wherein the observation parameter vector includes position corrections or velocity corrections for the three axes and the change in clock speed between adjacent epochs.

[0008] According to another aspect of the present invention, a computing device is provided, comprising a processor and a memory, wherein the memory stores program instructions which are executed by the processor to implement the high-precision positioning method described above.

[0009] According to another aspect of the present invention, a computer-readable medium is provided that stores program instructions which are executed to implement the high-precision positioning method described above.

[0010] Compared with existing technologies, the present invention can effectively eliminate pseudorange observations with gross errors, Doppler observations, and carrier observations with cycle slips, thereby improving the accuracy and precision of the RTK high-precision positioning method. Attached Figure Description

[0011] Figure 1 This is a flowchart illustrating one embodiment of a high-precision positioning method according to the present invention;

[0012] Figure 2 This is a flowchart illustrating one embodiment of the method for effectively eliminating pseudorange observations with gross errors in the present invention.

[0013] Figure 3 This is a flowchart illustrating one embodiment of the method for effectively eliminating Doppler observations with gross errors in this invention; and

[0014] Figure 4 This is a flowchart illustrating one embodiment of the method for effectively removing carrier measurements with cycle slips in this invention. Detailed Implementation

[0015] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided.

[0016] This invention focuses on describing the high-precision positioning method for the interepoch difference part, without emphasizing basic methods such as satellite position, pseudorange single-point positioning, double-difference observation method, Kalman filtering, and integer ambiguity fixing.

[0017] Figure 1 This is a flowchart illustrating one embodiment of a high-precision positioning method 100 according to the present invention. Figure 1 As shown, the high-precision positioning method includes the following steps.

[0018] Step 110: Effectively eliminate pseudorange observations with gross errors.

[0019] Step 120: Effectively eliminate Doppler observations with gross errors.

[0020] Step 130: Effectively remove carrier observations with cycle slips.

[0021] The effective removal of observations with gross errors or cycle slips mentioned in this article refers to removing observations with significant impact and large gross errors or cycle slips, rather than requiring the removal of all observations with gross errors or cycle slips.

[0022] Specifically, the high-precision positioning method 100 is a GNSS RTK high-precision positioning method.

[0023] Figure 2 This is a flowchart illustrating one embodiment of the method 200 for effectively eliminating pseudorange observations with gross errors in this invention. Figure 2 As shown, the method includes the following steps.

[0024] Step 210: Calculate the pseudorange observation parameter vector based on the pseudorange change between adjacent epochs, where the pseudorange change between adjacent epochs is the difference between the pseudorange observation values ​​between adjacent epochs.

[0025] Specifically, the pseudorange observation parameter vector is calculated based on the pseudorange observation equation between adjacent epochs. The pseudorange observation equation between adjacent epochs is as follows:

[0026]

[0027] X P =[dX dY dZ dT] T

[0028] In the formula, ΔP represents the change in pseudorange between adjacent epochs; Δρ represents the change in satellite-to-Earth distance between adjacent epochs. dX, dY, and dZ represent the projections of the satellite-Earth distance vector of the current epoch onto the X, Y, and Z axes, respectively; dX, dY, and dZ represent the position corrections along the X, Y, and Z axes, respectively; dT represents the change in clock speed between epochs, X P Let represent the pseudorange observation parameter vector, and ε represent the error of the observation.

[0029] Based on the pseudorange observation equation, dX, dY, dZ, and dT in the pseudorange observation parameter vector can be calculated using the least squares method or Kalman filtering.

[0030] Step 220: Calculate the pseudorange residual of the pseudorange observation value for the current epoch based on the pseudorange variation between adjacent epochs, the satellite-to-Earth distance variation between adjacent epochs, and the pseudorange observation parameter vector.

[0031] Specifically, the pseudorange residuals of the pseudorange observations at the current epoch are calculated according to the following pseudorange residual equation:

[0032] V P =BX P -(ΔP-Δρ)

[0033] in V P This represents the pseudorange residual of the pseudorange observations at the current epoch.

[0034] Step 230: Determine whether there are gross errors in the pseudorange observations based on the pseudorange residuals.

[0035] The pseudorange residual V of the i-th pseudorange observation is calculated using the following formula. Pi threshold σ Pi :

[0036]

[0037] Where R Pi Let be the variance of the i-th pseudorange observation.

[0038] If the threshold σ Pi If the value is greater than a predetermined value, the i-th pseudorange observation is considered to have a gross error and is marked; otherwise, the i-th pseudorange observation is considered to have no gross error. The predetermined value is preferably 9.0, but it can also be other values, such as 16.0.

[0039] If, or if at least one pseudorange observation has a gross error, proceed to step 240, perform a statistical analysis on all pseudorange observations with gross errors, and then proceed to step 250.

[0040] If none of the remaining pseudorange observations contain gross errors, then this process ends.

[0041] Step 250: Determine whether the unit weight mean square error of all current pseudorange observations meets the requirements.

[0042] The method for calculating the unit weight mean square error σ0 is as follows:

[0043]

[0044] Here, p represents the weight matrix of the pseudorange observation equation, n is the total number of remaining pseudorange observations, and t is the number of parameters in the pseudorange observation parameter vector. In this embodiment, t = 4.

[0045] If the requirements are met, this process ends.

[0046] If the conditions are not met, proceed to step 260.

[0047] Step 260: After removing the pseudorange observation with the largest gross error, return the remaining pseudorange observations to step 210 for iterative calculation. That is, in step 210, the pseudorange observation parameter vector is recalculated based on the remaining pseudorange observations, and subsequent steps 220, 230, 240, and 260 are performed until the unit weight mean square error of all remaining pseudorange observations meets the requirements or there are no gross errors in all remaining pseudorange observations.

[0048] Figure 3 This is a flowchart illustrating one embodiment of the method 300 for effectively eliminating Doppler observations with gross errors in this invention. Figure 3 As shown, the method 300 for effectively eliminating Doppler observations with gross errors includes the following steps.

[0049] Step 310: Calculate the Doppler observation parameter vector based on the Doppler variation between adjacent epochs.

[0050] Specifically, the Doppler observation parameter vector is calculated based on the Doppler observation equations between adjacent epochs. The Doppler observation equations between adjacent epochs are as follows:

[0051]

[0052] X D =[dV X dV Y dV Z dT] T

[0053] In the formula, λ represents the carrier wavelength, and ΔD represents the Doppler variation between adjacent epochs; This represents the change in the rate of change of the satellite-Earth distance between adjacent epochs. dV represents the projection of the satellite-Earth distance vector of the current epoch onto the X, Y, and Z axes, respectively; X dV Y dV Z These represent the velocity corrections for the X, Y, and Z axes, respectively; dT represents the change in clock speed between epochs, X D Let represent the Doppler observation parameter vector, and ε represent the error of the observation.

[0054] Step 320: Calculate the Doppler residuals of the Doppler observations for the current epoch based on the Doppler variation between adjacent epochs, the variation rate of satellite-to-Earth distance between adjacent epochs, and the Doppler observation parameter vector.

[0055] Specifically, the Doppler residuals of the Doppler observations at the current epoch are calculated based on the Doppler residual equation:

[0056]

[0057] in V D This represents the Doppler residual of the Doppler observations at the current epoch.

[0058] Step 330: Determine whether there are gross errors in the Doppler observations based on the Doppler residuals.

[0059] Specifically, the Doppler residual V of the i-th Doppler observation is calculated according to the following formula. Di threshold σ Di :

[0060]

[0061] Where R Di Let be the variance of the i-th Doppler observation.

[0062] If the threshold σ Di If the value is greater than a predetermined value, the i-th Doppler observation is considered to have a gross error, and the i-th Doppler observation is marked. The predetermined value is preferably 9.0, but it can also be other values, such as 16.0.

[0063] If an outlier exists, or if at least one Doppler observation has an outlier, proceed to step 340 to perform a statistical analysis on all Doppler observations with outliers, and then proceed to step 350.

[0064] If no gross errors are found in any of the remaining Doppler observations, then this process ends.

[0065] Step 350: Determine whether the unit weight mean square error of all current Doppler observations meets the requirements.

[0066] The method for calculating the unit weight error σ0 is as follows:

[0067]

[0068] In the formula, p represents the weight matrix of the Doppler observation equation, n is the total number of remaining Doppler observations, and t is the number of parameters in the Doppler observation parameter vector.

[0069] If the requirements are met, this process ends.

[0070] If the conditions are not met, proceed to step 360.

[0071] Step 360: After removing the Doppler observation with the largest gross error, return the remaining Doppler observations to step 310 for iterative calculation. That is, in step 310, the Doppler observation parameter vector is recalculated based on the remaining Doppler observations, and subsequent steps 320, 330, 340, and 360 are performed until the unit weight mean square error of all remaining Doppler observations meets the requirements or there are no gross errors in all remaining Doppler observations.

[0072] Figure 4 This is a flowchart illustrating one embodiment of the method 400 for effectively removing carrier observations with cycle slips in this invention. Figure 4 As shown, the method 400 for effectively removing carrier observations with cycle slips includes the following steps.

[0073] Step 410: Calculate the carrier observation parameter vector based on the carrier change between adjacent epochs.

[0074] Specifically, the carrier observation parameter vector is calculated based on the carrier observation equation between adjacent epochs. The carrier observation equation between adjacent epochs is as follows:

[0075]

[0076]

[0077] In the formula, λ represents the carrier wavelength. Δρ represents the carrier wave variation between adjacent epochs; Δρ represents the satellite-to-Earth distance variation between adjacent epochs. dX, dY, and dZ represent the projections of the satellite-Earth distance vector of the current epoch onto the X, Y, and Z axes, respectively; dX, dY, and dZ represent the position corrections along the X, Y, and Z axes, respectively; dT represents the change in clock speed between epochs. Let represent the carrier observation parameter vector, and ε represent the error of the observation.

[0078] Step 420: Calculate the carrier residual of the carrier observation value at the current epoch based on the carrier variation between adjacent epochs, the satellite-to-ground distance variation between adjacent epochs, and the carrier observation parameter vector.

[0079] Specifically, the carrier residual of the carrier observation at the current epoch is calculated based on the carrier residual equation:

[0080]

[0081] in This represents the carrier residual of the carrier observation at the current epoch;

[0082] Step 430: Determine whether the carrier observation value has a cycle slip based on the carrier residual.

[0083] Specifically, the carrier residual of the i-th carrier observation is calculated according to the following formula. threshold

[0084]

[0085] in Let be the variance of the i-th carrier observation.

[0086] If threshold If the value is greater than a predetermined value, the i-th carrier observation is considered to have a cycle slip, and the i-th carrier observation is marked. The predetermined value is preferably 9.0, but it can also be other values, such as 16.0.

[0087] If a cycle slip exists, or if at least one carrier observation has a cycle slip, proceed to step 440, count all carrier observations with cycle slips, and then proceed to step 450.

[0088] If none of the remaining carrier observations have cycle slips, then this process ends.

[0089] Step 450: Determine whether the unit weight mean square error of all current carrier observations meets the requirements.

[0090] The method for calculating the unit weight mean square error σ0 is as follows:

[0091]

[0092] In the formula, p represents the weight matrix of the carrier observation equation, n is the total number of remaining carrier observations, and t is the number of parameters in the carrier observation parameter vector.

[0093] If the requirements are met, this process ends.

[0094] If the conditions are not met, proceed to step 460.

[0095] It's important to note that p, t, and n represent different parameters in different methods (200, 300, 400), but they all share a common characteristic: they are all observations, differing only in the type of observation. For simplicity, parameters with the same properties are represented by the same notation.

[0096] Step 460: After removing the carrier observation with the largest cycle slip, return the remaining carrier observations to step 410 for iterative calculation. That is, in step 410, the carrier observation parameter vector is recalculated based on the remaining carrier observations, and subsequent steps 420, 430, 440, and 460 are performed until the unit weight mean square error of all remaining carrier observations meets the requirements or there are no cycle slips in all remaining carrier observations.

[0097] In a preferred embodiment, at the end of method 400, for the remaining carrier observations, if the carrier observation is greater than a predetermined cycle, it still needs to be marked as a cycle slip. The predetermined cycle can be 1 cycle. Thus, when the ambiguity search fails in the current epoch according to the Iambda algorithm, the position calculated based on the position correction in the carrier observation parameter vector calculated in the current epoch can be used as the position calculated in the current epoch, and the ambiguity that was fixed in the previous epoch and does not have a cycle slip in the current epoch can be passed to the next epoch. This effectively improves the ambiguity fixation rate.

[0098] In this part of the invention, inter-epoch difference techniques are applied to effectively detect pseudorange, Doppler gross errors, and carrier observation cycle slips for three types of GNSS observations in complex environments. This method not only detects anomalous observations but also effectively improves the fixation rate of integer ambiguity. It is a computationally efficient method for improving the accuracy and reliability of RTK positioning in complex environments.

[0099] During the process of eliminating observations with gross errors or cycle slips, pseudorange, Doppler, and carrier observation parameter vectors are continuously calculated. The velocity of the GNSS receiver can be calculated based on the velocity correction in the Doppler observation parameter vector, and the position of the GNSS receiver can be calculated based on the position correction in the carrier observation parameter vector. This part is prior art and not the focus of this invention, therefore it will not be described in detail.

[0100] Combining methods 200, 300, and 400, a common feature can be found. Therefore, this invention also provides a high-precision positioning method based on inter-epoch difference, which includes: calculating an observation parameter vector based on the change in observation values ​​between adjacent epochs, wherein the change in observation values ​​between adjacent epochs is the difference between the observation values ​​between adjacent epochs; calculating the residual of the observation values ​​at the current epoch based on the change in observation values ​​between adjacent epochs, the change in satellite-to-Earth distance or the change in the rate of change of satellite-to-Earth distance between adjacent epochs, and the observation parameter vector; determining whether the observation values ​​have gross errors or cycle slips based on the residuals; if so, determining whether the unit weight mean square error of all current observation values ​​meets the requirements; if not, removing the observation value with the largest gross error or cycle slip, and recalculating the observation parameter vector and subsequent operations based on the remaining observation values, until the unit weight mean square error of all remaining observation values ​​meets the requirements or all remaining observation values ​​do not have gross errors or cycle slips; wherein the observation parameter vector includes position corrections or velocity corrections for the three axes and the clock speed change between adjacent epochs.

[0101] The observed values ​​can be carrier, pseudorange, or Doppler observations, and the observation parameter vector can be a carrier, pseudorange, or Doppler observation parameter vector.

[0102] In this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.

[0103] In this document, the directional terms such as front, back, top, and bottom are defined based on the location of the components in the accompanying drawings and their relative positions to each other, solely for the purpose of clarity and convenience in expressing the technical solution. It should be understood that the use of these directional terms should not limit the scope of protection claimed in this application.

[0104] Where there is no conflict, the above embodiments and features described herein can be combined with each other.

[0105] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-precision positioning method, characterized in that: It includes: Calculate a pseudorange observation parameter vector according to the pseudorange change between adjacent epochs, wherein the pseudorange change between adjacent epochs is the difference between the pseudorange observation values ​​between adjacent epochs, calculate a pseudorange residual of the pseudorange observation value of the current epoch according to the pseudorange change between adjacent epochs, the satellite-to-earth distance change between adjacent epochs, and the pseudorange observation parameter vector, and judge whether there is a gross error in the pseudorange observation value according to the pseudorange residual, and if so, judge whether the unit weighted mean error of all current pseudorange observation values ​​meets the requirements, and if not, calculate the pseudorange observation parameter vector again based on the remaining pseudorange observation values ​​and subsequent operations, until the unit weighted mean error of all remaining pseudorange observation values ​​meets the requirements or there is no gross error in all remaining pseudorange observation values; A Doppler observation parameter vector is calculated according to the Doppler variation between adjacent epochs, wherein the Doppler variation between adjacent epochs is the difference between the Doppler observation values ​​between adjacent epochs; a Doppler residual of the Doppler observation value of the current epoch is calculated according to the Doppler variation between adjacent epochs, the variation of the satellite-to-earth distance variation rate between adjacent epochs, and the Doppler observation parameter vector; and whether the Doppler observation value has a gross error is determined according to the Doppler residual; if so, whether the unit weighted mean error of all current Doppler observation values ​​meets the requirement; if not, the Doppler observation value with the largest gross error is eliminated, and the Doppler observation parameter vector and subsequent operations are calculated again based on the remaining Doppler observation values ​​until the unit weighted mean error of all remaining Doppler observation values ​​meets the requirement or all remaining Doppler observation values ​​do not have a gross error; Calculate a carrier observation parameter vector according to the carrier change amount between adjacent epochs, wherein the carrier change amount between adjacent epochs is the difference between the carrier observation values ​​between adjacent epochs; calculate the carrier residual of the carrier observation value of the current epoch according to the carrier change amount between adjacent epochs, the satellite-to-earth distance change amount between adjacent epochs, and the carrier observation parameter vector; determine whether the carrier observation value has a cycle slip according to the carrier residual; if so, determine whether the unit weighted mean error of all current carrier observation values ​​meets the requirement; if not, recalculate the carrier observation parameter vector and subsequent operations based on the remaining carrier observation values ​​after eliminating the carrier observation value with the largest cycle slip, until the unit weighted mean error of all remaining carrier observation values ​​meets the requirement or all remaining carrier observation values ​​do not have cycle slips; Among them, the pseudorange observation parameter vector includes the position correction numbers of the three axes and the clock speed change between adjacent epochs, the Doppler observation parameter vector includes the velocity correction numbers of the three axes and the clock speed change between adjacent epochs, and the carrier observation parameter vector includes the position correction numbers of the three axes and the clock speed change between adjacent epochs.

2. The high-precision positioning method according to claim 1, characterized in that: The pseudorange observation parameter vector is calculated based on the pseudorange variation between adjacent epochs: The pseudorange observation parameter vector is calculated based on the pseudorange observation equation between adjacent epochs. The pseudorange observation equation between adjacent epochs is: X P =[dX dY dZ dT] T Where ΔP represents the pseudorange change between adjacent epochs; Δρ represents the change in satellite-earth distance between adjacent epochs; They represent the projection of the satellite-to-earth distance vector of the current epoch on the X, Y, and Z axes respectively; dX, dY, and dZ represent the position corrections of the X, Y, and Z axes respectively; dT represents the change in clock speed between epochs, X P represents the pseudorange observation parameter vector, ε represents the error of the observation value, The pseudorange residual of the pseudorange observation value of the current epoch is calculated based on the pseudorange change between adjacent epochs, the satellite-to-earth distance change between adjacent epochs, and the pseudorange observation parameter vector: The pseudorange residual of the pseudorange observation value of the current epoch is calculated according to the pseudorange residual equation: V P =BX P -(ΔP-Δr) in V P The pseudorange residual representing the pseudorange observation value of the current epoch; Judging whether there is a gross error in the pseudorange observation value according to the pseudorange residual is: The pseudorange residual V of the i-th pseudorange observation value is calculated according to the following formula: Pi The threshold σ Pi : Where R Pi is the variance of the ith pseudorange observation, If the threshold σ Pi If it is greater than a preset value, it is considered that there is a gross error in the i-th pseudorange observation value, and the i-th pseudorange observation value is marked; The calculation method of unit weight error σ0 is as follows: Where p represents the weight matrix of the pseudorange observation equation, n is the total number of remaining pseudorange observations, and t is the number of parameters in the pseudorange observation parameter vector.

3. The high-precision positioning method according to claim 1, characterized in that: The Doppler observation parameter vector is calculated based on the Doppler variation between adjacent epochs: The Doppler observation parameter vector is calculated based on the Doppler observation equation between adjacent epochs. The Doppler observation equation between adjacent epochs is: X D =[dV X dV Y dV Z dV t ] T In the formula, λ represents the carrier wavelength, and ΔD represents the Doppler change between adjacent epochs; It represents the change of the satellite-earth distance change rate between adjacent epochs; Respectively represent the projection of the satellite-to-earth distance vector of the current epoch on the X, Y, and Z axes; dV X , dV Y , dV Z Respectively represent the velocity correction values ​​of X, Y, and Z axes; dV t represents the change in clock speed between epochs, X D represents the Doppler observation parameter vector, ε represents the error of the observation value, The Doppler residual of the Doppler observation value of the current epoch is calculated based on the Doppler change between adjacent epochs, the change in the satellite-to-earth distance change rate between adjacent epochs, and the Doppler observation parameter vector: The Doppler residual of the Doppler observation at the current epoch is calculated according to the Doppler residual equation: in V D The Doppler residual represents the Doppler observation value of the current epoch; The method of judging whether there is a gross error in the Doppler observation value according to the Doppler residual is: The Doppler residual V of the i-th Doppler observation is calculated according to the following formula: Di The threshold σ Di : Where R Di is the variance of the ith Doppler observation, If the threshold σ Di If it is greater than a preset value, it is considered that there is a gross error in the i-th Doppler observation value, and the i-th Doppler observation value is marked; The calculation method of unit weight error σ0 is as follows: Where p represents the weight matrix of the Doppler observation equation, n is the total number of remaining Doppler observations, and t is the number of parameters in the Doppler observation parameter vector.

4. The high-precision positioning method according to claim 1, characterized in that: The carrier observation parameter vector is calculated based on the carrier change between adjacent epochs: The carrier observation parameter vector is calculated based on the carrier observation equation between adjacent epochs. The carrier observation equation between adjacent epochs is: Where λ represents the carrier wavelength, represents the carrier change between adjacent epochs; Δρ represents the satellite-to-earth distance change between adjacent epochs; They represent the projection of the satellite-to-earth distance vector of the current epoch on the X, Y, and Z axes respectively; dXdY dZ represent the position corrections of the X, Y, and Z axes respectively; dT represents the change in clock speed between epochs, represents the carrier observation parameter vector, ε represents the error of the observation value, The carrier residual of the carrier observation value of the current epoch is calculated based on the carrier change between adjacent epochs, the satellite-to-earth distance change between adjacent epochs, and the carrier observation parameter vector: The carrier residual of the carrier observation value of the current epoch is calculated according to the carrier residual equation: in The carrier residual representing the carrier observation value of the current epoch; The method of judging whether the carrier observation value has a cycle slip according to the carrier residual is: The carrier residual of the i-th carrier observation value is calculated according to the following formula Threshold in is the variance of the i-th carrier observation, If the threshold If it is greater than a predetermined value, it is considered that the i-th carrier observation value has a cycle slip, and the i-th carrier observation value is marked; The calculation method of unit weight error σ0 is as follows: Where p represents the weight matrix of the carrier observation equation, n is the total number of remaining carrier observation values, and t is the number of parameters in the carrier observation parameter vector.

5. The high-precision positioning method according to claim 1, characterized in that: For the remaining carrier observation values, when the carrier observation value is greater than the predetermined cycle, the carrier observation value still needs to be marked as a cycle slip. When the ambiguity search in the current epoch fails according to the lambda algorithm, the position calculated based on the position correction number in the carrier observation parameter vector calculated in the current epoch is used as the position calculated in the current epoch, and the ambiguity that has been fixed in the previous epoch and has no cycle slip in the current epoch is passed to the next epoch.

6. A high-precision positioning method based on inter-epoch differences, characterized in that: It includes: An observation parameter vector is calculated according to the amount of change of observation values ​​between adjacent epochs, wherein the amount of change of observation values ​​between adjacent epochs is the difference of observation values ​​between adjacent epochs. A residual of the observation value of the current epoch is calculated according to the amount of change of observation values ​​between adjacent epochs, the amount of change of satellite-to-earth distance or the amount of change of satellite-to-earth distance change rate between adjacent epochs, and the observation parameter vector. It is judged according to the residual whether the observation value has a gross error or a cycle slip. If so, it is judged whether the unit weighted mean error of all current observation values ​​meets the requirements. If not, the observation value with the largest gross error or cycle slip is eliminated, and the observation parameter vector and subsequent operations are calculated again based on the remaining observation values ​​until the unit weighted mean error of all remaining observation values ​​meets the requirements or all remaining observation values ​​do not have gross errors or cycle slips. The observation parameter vector includes the position correction or velocity correction of the three axes and the clock speed change between adjacent epochs.

7. The high-precision positioning method according to claim 6, characterized in that: The observation value is a pseudorange observation value, the observation value change is a pseudorange change, and the observation parameter vector is a pseudorange observation parameter vector. The pseudorange observation parameter vector is calculated based on the pseudorange change between adjacent epochs: The pseudorange observation parameter vector is calculated based on the pseudorange observation equation between adjacent epochs. The pseudorange observation equation between adjacent epochs is: X P =[dX dY dZ dT] T Where ΔP represents the pseudorange change between adjacent epochs; Δρ represents the change in satellite-earth distance between adjacent epochs; They represent the projection of the satellite-to-earth distance vector of the current epoch on the X, Y, and Z axes respectively; dX, dY, and dZ represent the position corrections of the X, Y, and Z axes respectively; dT represents the change in clock speed between epochs, X P represents the pseudorange observation parameter vector, ε represents the error of the observation value, The pseudorange residual of the pseudorange observation value of the current epoch is calculated based on the pseudorange change between adjacent epochs, the satellite-to-earth distance change between adjacent epochs, and the pseudorange observation parameter vector: The pseudorange residual of the pseudorange observation value of the current epoch is calculated according to the pseudorange residual equation: V P =BX P -(ΔP-Δr) in V P The pseudorange residual representing the pseudorange observation value of the current epoch; Judging whether there is a gross error in the pseudorange observation value according to the pseudorange residual is: The pseudorange residual V of the i-th pseudorange observation value is calculated according to the following formula: Pi The threshold σ Pi : Where R Pi is the variance of the ith pseudorange observation, If the threshold σ Pi If it is greater than a preset value, it is considered that there is a gross error in the i-th pseudorange observation value, and the i-th pseudorange observation value is marked; The calculation method of unit weight error σ0 is as follows: Here, p represents the weight matrix of the pseudorange observation equation, n is the total number of remaining pseudorange observations, and t is the number of parameters in the pseudorange observation parameter vector.

8. The high-precision positioning method according to claim 6, characterized in that: The observation value is a Doppler observation value, the observation value change is a Doppler change, and the observation parameter vector is a Doppler observation parameter vector. The Doppler observation parameter vector is calculated based on the Doppler variation between adjacent epochs: The Doppler observation parameter vector is calculated based on the Doppler observation equation between adjacent epochs. The Doppler observation equation between adjacent epochs is: X D =[dV X dV Y dV Z dV t ] T In the formula, λ represents the carrier wavelength, and ΔD represents the Doppler change between adjacent epochs; It represents the change of the satellite-earth distance change rate between adjacent epochs; Respectively represent the projection of the satellite-to-earth distance vector of the current epoch on the X, Y, and Z axes; dV X , dV Y , dV Z Respectively represent the velocity correction values ​​of X, Y, and Z axes; dV t represents the change in clock speed between epochs, X D represents the Doppler observation parameter vector, ε represents the error of the observation value, The Doppler residual of the Doppler observation value of the current epoch is calculated based on the Doppler change between adjacent epochs, the change in the satellite-to-earth distance change rate between adjacent epochs, and the Doppler observation parameter vector: The Doppler residual of the Doppler observation at the current epoch is calculated according to the Doppler residual equation: in V D The Doppler residual represents the Doppler observation value of the current epoch; Judging whether there is a gross error in the Doppler observation value according to the Doppler residual is: The Doppler residual V of the i-th Doppler observation is calculated according to the following formula: Di The threshold σ Di : Where R Di is the variance of the ith Doppler observation, If the threshold σ Di If it is greater than a preset value, it is considered that there is a gross error in the i-th Doppler observation value, and the i-th Doppler observation value is marked; The calculation method of unit weight error σ0 is as follows: Where p represents the weight matrix of the Doppler observation equation, n is the total number of remaining Doppler observations, and t is the number of parameters in the Doppler observation parameter vector.

9. The high-precision positioning method according to claim 6, characterized in that: The observation value is the carrier observation value, the observation value change is the carrier change, and the observation parameter vector is the carrier observation parameter vector. The carrier observation parameter vector is calculated based on the carrier change between adjacent epochs: The carrier observation parameter vector is calculated based on the carrier observation equation between adjacent epochs. The carrier observation equation between adjacent epochs is: Where λ represents the carrier wavelength, represents the carrier change between adjacent epochs; Δρ represents the satellite-to-earth distance change between adjacent epochs; They represent the projection of the satellite-to-earth distance vector of the current epoch on the X, Y, and Z axes respectively; dXdY dZ represent the position corrections of the X, Y, and Z axes respectively; dT represents the change in clock speed between epochs, represents the carrier observation parameter vector, ε represents the error of the observation value, The carrier residual of the carrier observation value of the current epoch is calculated based on the carrier change between adjacent epochs, the satellite-to-earth distance change between adjacent epochs, and the carrier observation parameter vector: The carrier residual of the carrier observation value of the current epoch is calculated according to the carrier residual equation: in The carrier residual representing the carrier observation value of the current epoch; The method of judging whether the carrier observation value has a cycle slip according to the carrier residual is: The carrier residual of the i-th carrier observation value is calculated according to the following formula Threshold in is the variance of the i-th carrier observation, If the threshold If it is greater than a predetermined value, it is considered that the i-th carrier observation value has a cycle slip, and the i-th carrier observation value is marked; The calculation method of unit weight error σ0 is as follows: Here, p represents the weight matrix of the carrier observation equation, n is the total number of remaining carrier observation values, and t is the number of parameters in the carrier observation parameter vector.

10. A computing device comprising a processor and a memory, wherein the memory stores program instructions, and the program instructions are executed by the processor to implement the high-precision positioning method as described in any one of claims 1-9.

11. A computer-readable medium storing program instructions, wherein the program instructions are executed to implement the high-precision positioning method according to any one of claims 1 to 9.

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