Methods and equipment for smoothly switching between ground-based and satellite-based positioning calculation modes

Abstract

This invention provides a method and apparatus for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes. The user terminal uses the ground-based augmentation positioning calculation mode as the primary augmentation positioning mode. It determines the availability of ground-based augmentation based on pre-set anomaly detection indicators; if unavailable, it smoothly switches to satellite-based augmentation. When switching from ground-based to satellite-based augmentation as the primary mode, an asynchronous positioning method with additional time-cumulative error compensation is employed, combined with deviation compensation to maintain stable positioning accuracy at the user terminal. Simultaneously, ground-based augmentation calculation information is used to constrain satellite-based augmentation, accelerating its convergence speed. When switching back from satellite-based to ground-based augmentation as the primary mode, prior information provided by satellite-based augmentation is used to constrain ground-based augmentation, improving the restart speed of the ground-based augmentation positioning mode. This invention improves the continuity, smoothness, and positioning consistency of switching between ground-based and satellite-based augmentation positioning calculation modes by optimizing the switching process, thereby enhancing the reliability of BeiDou augmentation positioning technology.

Description

Technical Field

[0001] This invention belongs to the field of GNSS satellite positioning technology, and in particular relates to a technical solution for achieving smooth switching between ground-based and satellite-based positioning calculation modes. Background Technology

[0002] Currently, GNSS satellites, such as my country's BeiDou, are developing rapidly, but there are still some sub-fields that require continuous improvement. The issue of smooth and continuous switching between satellite and ground-based augmentation is a crucial aspect of this. The following section details the current state of the relevant technologies.

[0003] 1. BeiDou Ground-Based Augmentation

[0004] The BeiDou Ground-Based Augmentation System (BDA) is a technology used to improve the positioning accuracy and reliability of the BeiDou Navigation Satellite System. By deploying a large number of monitoring stations on the ground to form a network, the BDA receives observation data from BeiDou satellites, processes it to generate high-precision positioning service information, and provides augmentation services through a ground broadcast network. This improves the positioning and navigation service performance for ground users, achieving positioning accuracy at the centimeter or even millimeter level.

[0005] 2. BeiDou Satellite-Based Precision Point Positioning (PPP)

[0006] BeiDou satellite-based augmentation is a method that improves the positioning accuracy of ground user terminals by broadcasting real-time differential correction information, including satellite orbit, satellite clock bias, and atmospheric delay, to users via geostationary orbit (GEO) satellites. BeiDou satellite-based precise point positioning service is broadcast via B2b signals, covering my country and surrounding areas, and providing free augmented positioning services.

[0007] 3. BeiDou Ground-Based and Satellite-Based Integrated Augmentation

[0008] The BeiDou ground-based augmentation system can converge instantaneously with centimeter-level accuracy, but it relies on a dense network of reference stations and terrestrial communication networks. This can lead to decreased network stability, especially when dealing with a large number of users. The BeiDou satellite-based PPP augmentation service does not rely on terrestrial communication networks, requiring only a sparse global network of stations, but convergence takes tens of minutes. Therefore, ground-based and satellite-based augmentation systems are complementary. Integrated space-ground augmentation can significantly improve the efficiency of augmentation services. However, a direct hard switch between the two can cause jumps in positioning results, severely impacting the reliability and stability of user-enhanced positioning. Summary of the Invention

[0009] To address the issue of smooth switching between satellite-based and satellite-based augmentation modes, this invention provides a technical solution for achieving smooth switching between satellite-based and satellite-based positioning calculation modes.

[0010] To achieve the above objectives, the technical solution proposed in this invention is a method for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes. The user terminal uses the ground-based augmentation positioning calculation mode as the main mode for augmentation positioning. It judges whether ground-based augmentation is available according to a pre-set abnormal situation detection index. If it is unavailable, it starts the satellite-based augmentation positioning mode and smoothly switches to satellite-based augmentation.

[0011] When the main mode switches from ground-based augmentation to satellite-based augmentation, an asynchronous positioning method with additional time-cumulative error compensation is adopted. This method, combined with deviation compensation, maintains stable positioning accuracy at the user end. At the same time, it combines ground-based augmentation solution information to constrain satellite-based augmentation and accelerate the convergence speed of satellite-based augmentation.

[0012] When the main mode switches from satellite-based augmentation to ground-based augmentation, the prior information provided by satellite-based augmentation is used to constrain ground-based augmentation, thereby improving the restart speed of ground-based augmentation positioning mode.

[0013] Furthermore, the positioning results of ground-based augmentation are fitted with user motion trajectory data, and the fitting parameters are used as pre-set anomaly detection indicators. Combined with other anomaly detection indicators, the positioning quality is comprehensively evaluated.

[0014] Furthermore, the anomaly detection indicators include the accuracy of three-dimensional coordinates, PDOP value, ADOP value, GDOP value, HDOP value, number of satellites, and / or positioning error distribution.

[0015] Furthermore, when the main mode switches from ground-based augmentation to satellite-based augmentation, an asynchronous positioning model combining RTK positioning and TDCP is constructed using the TDCP time accumulation error compensation method. When the main mode switches from ground-based augmentation to satellite-based augmentation, a consistency judgment and check is performed on the positioning accuracy of ground-based augmentation and satellite-based augmentation. When the positioning accuracy of the two calculation modes is consistent, the switch from ground-based augmentation positioning to satellite-based augmentation positioning is executed, thereby achieving a smooth switch.

[0016] Furthermore, the asynchronous positioning model combining RTK positioning and TDCP calculates the average value of the TDCP position change error sequence to obtain the system error, and uses the obtained system error to compensate for the positioning result; it also performs autocorrelation analysis on the TDCP position change error sequence to obtain the autocovariance, and uses the obtained autocovariance to predict real-time accuracy.

[0017] Furthermore, when the ground-based augmentation solution malfunctions and the main mode switches from ground-based augmentation to satellite-based augmentation, the ambiguity and position information output by the ground-based augmentation are combined with the variance and used as the virtual observation value according to the prior accuracy to constrain the initialization of the satellite-based augmentation, thereby reducing its convergence time. When the main mode switches from satellite-based augmentation to ground-based augmentation, the ambiguity and position information output by the satellite-based augmentation are combined with the variance and used as the prior information to constrain the initialization of the ground-based augmentation, thereby reducing its convergence time.

[0018] On the other hand, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, it implements the method described above for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes.

[0019] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, it implements the method described above for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes.

[0020] On the other hand, the present invention also provides a computer program product, including a computer program, which, when executed by a processor, implements the method described above for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes.

[0021] This invention provides a technical solution for smoothly switching between BeiDou ground-based and satellite-based augmentation positioning modes on the terminal side. Considering the complementary advantages of ground-based and satellite-based augmentation positioning modes in complex environments, the switching process suffers from result jumps and underutilization of the high precision of ground-based augmentation, severely impacting service accuracy, continuity, and consistency, thus reducing user experience. To address this challenge, when switching from ground-based to satellite-based augmentation, this invention first utilizes an asynchronous positioning method with added time-cumulative error compensation, deviation compensation, and accuracy consistency determination methods to reduce accuracy loss during system switching. Simultaneously, it uses the high-precision position and ambiguity information provided by ground-based augmentation to constrain satellite-based augmentation, reducing its convergence time. When switching from satellite-based to ground-based augmentation, this invention uses the position and other information provided by satellite-based augmentation to constrain ground-based augmentation, significantly shortening the re-initialization time of the ground-based augmentation positioning mode. When the performance of a single augmentation system is unstable, this invention optimizes the switching method to improve the continuity, smoothness, and positioning consistency of the switching between ground-based and satellite-based augmentation positioning modes, thereby enhancing the reliability of BeiDou augmentation positioning technology and demonstrating its practicality.

[0022] This invention provides a BeiDou ground-based augmentation smooth handover technology solution, which supports high-precision positioning performance with consistent accuracy across the entire region in areas with weak ground infrastructure and frequent augmentation service handover.

[0023] The present invention is simple and convenient to implement, highly practical, and solves the problems of low practicality and inconvenience in actual application of related technologies. It can improve user experience and has significant market value. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of an embodiment of the present invention.

[0025] Figure 2 This is an experimental scenario diagram of the seamless switching method for satellite-based / ground-based augmentation services according to an embodiment of the present invention.

[0026] Figure 3 This is a graph showing the change in TDCP positioning accuracy over time according to an embodiment of the present invention.

[0027] Figure 4 This is a comparison chart of PPP / TDCP coordinate positioning error sequences in an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of the physical structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0029] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0030] like Figure 1 As shown, this embodiment of the invention requires the user terminal to use the ground-based augmentation positioning solution mode as the main augmentation positioning mode. It determines the availability of ground-based augmentation based on pre-set anomaly detection indicators. If unavailable, it activates the satellite-based augmentation positioning mode, smoothly switching to satellite-based augmentation, and uses this as the output solution. In specific implementation, the user terminal can use BeiDou ground-based augmentation positioning solution as the main mode and satellite-based augmentation positioning solution mode as the auxiliary mode, with the main mode positioning result as the system output solution. Once the user terminal detects anomalies such as missing ground-based augmentation signals through pre-set detection indicators, resulting in abnormal accuracy of the main mode positioning result, the system will activate the satellite-based augmentation positioning solution mode.

[0031] When the positioning mode is switched from ground-based augmentation to satellite-based augmentation, an asynchronous positioning method with additional time accumulation error compensation and a deviation compensation method are used to maintain the stability of the user's positioning accuracy. At the same time, the satellite-based augmentation is constrained by ground-based augmentation solution information to accelerate the convergence speed of satellite-based augmentation.

[0032] Furthermore, this invention proposes that when the solution mode switches from ground-based augmentation positioning to satellite-based augmentation positioning, an asynchronous positioning method with additional time-cumulative error compensation and a deviation compensation method are first adopted to maintain the user's positioning accuracy to the maximum extent. At the same time, the high-precision position and ambiguity information provided before the ground-based augmentation solution anomaly is used to constrain satellite-based augmentation, thereby reducing the convergence time of satellite-based augmentation. The consistency judgment and verification of the positioning accuracy of ground-based augmentation and satellite-based augmentation are performed simultaneously. When the positioning accuracy of the two solution modes is consistent, the system switches from ground-based augmentation positioning to satellite-based augmentation positioning, thereby achieving a smooth switch.

[0033] When the main mode switches from satellite-based augmentation to ground-based augmentation, the high-precision position and ambiguity information provided by the satellite-based augmentation mode are used to constrain the ground-based augmentation mode, thereby accelerating the reinitialization of the ground-based augmentation mode. In specific implementation, by using the prior information such as high-precision position and ambiguity provided by satellite-based augmentation to constrain ground-based augmentation, the restart speed of the ground-based augmentation positioning mode can be improved.

[0034] The following provides further details on the implementation:

[0035] 1. Anomaly detection indicators for ground-based and satellite-based augmentation

[0036] First, user motion trajectory data is fitted to the positioning results from both ground-based and satellite-based augmentation methods. Then, using a weighted average method, combined with fitting parameters, internal coincidence accuracy (STD), and other indicators, the optimal factors to consider are PDOP, ADOP, GDOP, HDOP, and the number of satellites, to comprehensively evaluate positioning quality. When determining the weights of each indicator, machine learning is preferred to finely control the magnitude of each factor's influence, ensuring that the comprehensive indicator accurately integrates all factors and yields anomaly detection indicators, thereby optimizing positioning system performance and user experience.

[0037] The embodiment further proposes to simultaneously determine anomaly detection indicators for both ground-based and satellite-based augmentation positioning modes, specifically including the following steps:

[0038] The historical positioning results of ground-based and satellite-based augmentation are fitted with user motion trajectory data, and the historical user motion trajectory data is used as the training dataset for machine learning networks. The fitting parameters are used as pre-set anomaly detection indicators. If there is a large difference in the user trajectory, it is judged as an anomaly.

[0039] The system calculates the three-dimensional coordinate convergence accuracy, PDOP, ADOP, GDOP, HDOP, VDOP, satellite number, and / or positioning error distribution for both ground-based and satellite-based augmentation positioning modes. These indicators are used as anomaly detection criteria; if an indicator exceeds a threshold, it is considered an anomaly. PDOP (Position Dilution of Precision) is a three-dimensional precision factor representing the sparsity of position accuracy, comprehensively considering the accuracy of three-dimensional positioning (longitude, latitude, and altitude). A lower PDOP value indicates higher positioning accuracy. HDOP (Horizontal Dilution of Precision) is a horizontal precision factor representing the sparsity of horizontal accuracy, considering only the accuracy of two-dimensional plane (longitude and latitude) positioning. A lower HDOP value indicates higher horizontal positioning accuracy. VDOP (Vertical Dilution of Precision) is a vertical geometric precision factor representing the sparsity of vertical accuracy, focusing on the accuracy of altitude (vertical) positioning. A lower VDOP value indicates higher vertical positioning accuracy. TDOP (Time Dilution of Precision) is a time precision factor that represents the sparsity of time precision. A lower TDOP value indicates higher positioning accuracy in time. GDOP (Geometric Dilution of Precision) is a geometric precision factor that comprehensively considers the sparsity of precision in position, time, and altitude. GDOP is a more comprehensive indicator, combining the effects of all dimensions. ADOP (Ambiguity Dilution of Precision) is an ambiguity precision factor, an easily computed scalar diagnostic method used to measure the strength of the intrinsic model for successfully resolving ambiguities.

[0040] In specific implementation, the preferred approach is to first construct the parameter precision matrix D as follows:

[0041]

[0042] In the formula, These are elements within the parameter precision matrix. , .

[0043] The formula for calculating the PDOP value is:

[0044]

[0045] The formula for calculating the HDOP value is:

[0046]

[0047] The formula for calculating the VDOP value is:

[0048]

[0049] The formula for calculating the TDOP value is:

[0050]

[0051] The formula for calculating the GDOP value is as follows:

[0052]

[0053] Suppose that the real-valued floating-point estimator of the GNSS integer ambiguity vector a follows a certain pattern. The formula for calculating the ADOP value is as follows:

[0054]

[0055] In the formula, Represents the ambiguity variance matrix. n Indicates the number of ambiguities. Represents the ambiguity variable. This indicates determinant operations.

[0056] The calculation method for the accuracy index STD in the three-dimensional coordinate system is as follows:

[0057]

[0058]

[0059] In the formula, Indicates the current position. This represents the predicted location obtained by fitting the user's trajectory. This indicates the difference in the corresponding position.

[0060] 2. Asynchronous positioning method with additional time cumulative error compensation

[0061] First, during the initialization phase, the system error is calculated by averaging the TDCP position change error sequence, and autocorrelation analysis is performed to obtain the autocovariance. Then, when the carrier enters the motion phase, the system uses the system error generated in the previous phase to compensate for the positioning results and the autocovariance to perform real-time accuracy prediction.

[0062] 3. Criteria for judging the accuracy consistency between RTK asynchronous positioning and satellite-based augmentation

[0063] The positional accuracy of RTK asynchronous positioning is obtained by using the variance of the RTK output and the error propagation law. When the variance of the satellite-based augmentation output is compared with that of the satellite-based augmentation output, the accuracy of RTK asynchronous positioning and satellite-based augmentation is consistent when the two are similar.

[0064] 4. Ground-based augmentation accelerates satellite-based augmentation initialization.

[0065] By combining the ambiguity and location information output from ground-based augmentation with its variance, virtual observations are used to constrain the initialization of the satellite-based augmentation system, thereby reducing convergence time.

[0066] The embodiment further proposes that when the positioning mode is switched from ground-based augmentation to satellite-based augmentation, the specific steps include:

[0067] Using the TDCP time cumulative error compensation method, an asynchronous positioning model combining RTK positioning and TDCP is constructed. The average value of the TDCP position change error sequence is calculated to obtain the system error. The obtained system error is used to compensate for the positioning results. Autocorrelation analysis is performed on the TDCP position change error sequence to obtain the autocovariance. The obtained autocovariance is used to predict the real-time accuracy. Among them, TDCP (Time-Difference Carrier-Phase) is the differential carrier phase positioning mode between GNSS observation epochs.

[0068] The asynchronous positioning model combining RTK positioning and TDCP operates by simultaneously activating both RTK and TDCP modes during the static initialization phase. The RTK positioning results are used to analyze the systematic error and autocovariance of TDCP. During the motion phase, the TDCP analysis results from the static initialization phase are used to compensate for the positioning results and perform real-time accuracy prediction.

[0069] For ease of implementation and reference, the implementation methods of RTK positioning and TDCP are explained below:

[0070] At high sampling rates, the atmosphere remains unchanged between adjacent epochs, which is beneficial for the receiver. and satellite The carrier observation equation for the TDCP positioning method is as follows:

[0071]

[0072] In the formula, This represents the carrier observations after differential calculation between adjacent epochs. This represents the satellite-Earth distance after the difference between adjacent epochs. This represents the clock difference after differing between adjacent epochs. Indicates satellite clock bias, This represents the remaining noise items.

[0073] The carrier observation equation for the RTK positioning method is as follows:

[0074]

[0075] In the formula, This represents the double difference operator. and These represent carrier and pseudorange observations, respectively. Indicates the first Reference satellite for the baseline; They represent the first Public satellites with a baseline; Indicates a monitoring station; Indicates the first One base station; Indicates the geometric distance between the receiver and the satellite; This indicates ionospheric delay. For short baselines, the double difference is considered small enough to be negligible, while for medium and long baselines, a dual-frequency ionospheric-free combination can be used to eliminate it. This indicates tropospheric delay. After double difference at short baselines, it is considered small enough to be negligible. For medium- and long baselines or large elevation differences, random walk parameter estimation can be used to reduce the delay. The double difference represents the integer phase ambiguity of the carrier wave; Indicates the wavelength of the carrier wave; These are the measurement noises for the carrier wave and pseudorange, respectively. Therefore, Represents carrier observations, Indicates the geometric distance between the receiver and the satellite. Indicates ionospheric delay, Indicates tropospheric delay, The double difference represents the integer phase ambiguity of the carrier wave. Indicates carrier measurement noise, Represents pseudorange observations. This represents the measurement noise of the pseudorange.

[0076] Furthermore, the expression for the TDCP time accumulation error compensation method is as follows:

[0077]

[0078]

[0079]

[0080]

[0081] In the formula, Represents carrier observations, Indicates the error compensation coefficient. Indicates coordinate error. Represents geometric distance, Indicates receiver clock bias. Represents the speed of light. Indicates satellite clock bias, Indicates tropospheric delay, Indicates measurement noise. Indicates the recursive position. Indicates the initial position. Represents the recursive value. Represents the residual value. i、n Indicates the epoch, Represents the noise matrix. , , Represents the coefficient.

[0082] Based on the aforementioned accuracy consistency criteria, the accuracy of the RTK asynchronous model positioning result and the accuracy of the satellite-based augmentation positioning result are compared to determine whether a system switch is necessary. If the accuracy of the RTK asynchronous model positioning result is lower than that of the satellite-based augmentation positioning result, then the system is switched to satellite-based augmentation.

[0083] By combining the ambiguity and location information output by the ground-based augmentation positioning solution mode with its variance, and using a certain prior accuracy as virtual observation values ​​to constrain the initialization of the satellite-based augmentation system, the convergence time can be reduced.

[0084] The constraint equation for the prior information of ambiguity is:

[0085]

[0086] In the formula, Indicates foundation ambiguity information. This indicates satellite-based ambiguity information.

[0087] The constraint equation for the prior location information is:

[0088]

[0089] In the formula, Indicates foundation location information. This indicates the satellite-based location information.

[0090] The constraint equation for the virtual observations is:

[0091]

[0092] In the formula, Let M represent the coefficient matrix of the virtual observation equation, M represent the constant matrix of the virtual observation equation, and X represent the ambiguity and location parameters.

[0093] 5. Space-based augmentation accelerates ground-based augmentation initialization.

[0094] According to the switching design of this invention, when the ground-based augmentation solution malfunctions and the main mode switches from ground-based augmentation to satellite-based augmentation, the ambiguity and position information output by the ground-based augmentation are combined with their variance and used as virtual observations with a certain prior accuracy to constrain the initialization of the satellite-based augmentation, thereby reducing its convergence time. When the main mode switches from satellite-based augmentation to ground-based augmentation, the prior information output by the satellite-based augmentation is used to constrain the initialization of the ground-based augmentation, thereby reducing the convergence time. This includes combining the ambiguity and position information output by the satellite-based augmentation with their variance and using them as virtual observations to constrain the initialization of the ground-based augmentation system, thereby reducing the convergence time.

[0095] The following experimental results illustrate the effectiveness of the smooth switching method between ground-based and satellite-based augmentation positioning solution modes proposed in this embodiment.

[0096] See Figure 2 , Figure 2 The experimental design and scenario were demonstrated. The weather conditions were favorable, the satellite observation environment was open, and the experimental scenario was set on a school playground. The experimental equipment included a mobile vehicle carrying one GNSS multi-system satellite receiver and another GNSS multi-system satellite receiver serving as a base station.

[0097] Figure 3 This paper demonstrates the change in positioning error over time in the N / E / U (North, East, Sky) direction using the TDCP method proposed in this embodiment of the invention. Figure 4 The comparison of coordinate positioning error sequences using the PPP / TDCP methods is presented. Experimental results show that the TDCP method proposed in this patent achieves an elevation accuracy better than 10cm within 3 minutes of signal interruption and a planar accuracy better than 5cm within 9 minutes. The results also indicate that RTK positioning accuracy is higher than PPP before signal interruption. After signal interruption, the integrated space-ground system uses TDCP to maintain positioning accuracy. However, the error of TDCP will continuously increase over time. At a certain point in time, the accuracy of TDCP will match that of PPP; this point is the transition point between space-based and ground-based augmentation. Before this point, TDCP accuracy is higher than PPP, and the integrated space-ground system will use TDCP. After this point, the error of TDCP becomes greater than that of PPP, and the integrated space-ground system will switch back to PPP, achieving a smooth transition between space and ground.

[0098] Figure 5 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 5As shown, the electronic device may include a processor, a communications interface, a memory, and a communication bus, wherein the processor, communications interface, and memory communicate with each other via the communication bus. The processor can call logical instructions in the memory to execute a method for smoothly switching between ground-based and satellite-based positioning calculation modes. Furthermore, the logical instructions in the memory can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks. On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the methods provided by the above-described methods for smoothly switching between ground-based and satellite-based positioning calculation modes. Furthermore, the present invention also provides a non-transitory computer-readable storage medium storing a computer program that, when executed by a processor, implements the methods provided by the above-described methods for smoothly switching between ground-based and satellite-based positioning calculation modes. The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort. Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware.Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or certain parts of the embodiments. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes, characterized in that: The user terminal uses the ground-based augmentation positioning solution mode as the main mode of augmentation positioning. It judges whether the ground-based augmentation is available according to the pre-set abnormal situation detection index. If it is not available, it starts the satellite-based augmentation positioning mode and smoothly switches to satellite-based augmentation. When the main mode switches from ground-based augmentation to satellite-based augmentation, an asynchronous positioning method with additional time-cumulative error compensation is adopted. This method, combined with deviation compensation, maintains stable positioning accuracy at the user end. At the same time, it combines ground-based augmentation solution information to constrain satellite-based augmentation and accelerate the convergence speed of satellite-based augmentation. When the main mode switches from satellite-based augmentation to ground-based augmentation, the prior information provided by satellite-based augmentation is used to constrain ground-based augmentation, thereby improving the restart speed of ground-based augmentation positioning mode; When the main mode switches from ground-based augmentation to satellite-based augmentation, an asynchronous positioning model combining RTK positioning and TDCP is constructed using the TDCP time accumulation error compensation method. When the main mode switches from ground-based augmentation to satellite-based augmentation, a consistency judgment and check is performed on the positioning accuracy of ground-based augmentation and satellite-based augmentation. When the positioning accuracy of the two calculation modes is consistent, the switch from ground-based augmentation positioning to satellite-based augmentation positioning is executed, thereby achieving a smooth switch.

2. The method for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes according to claim 1, characterized in that: The positioning results of ground-based augmentation are fitted with user motion trajectory data. The fitted parameters are used as pre-set anomaly detection indicators. Combined with other anomaly detection indicators, the positioning quality is comprehensively evaluated.

3. The method for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes according to claim 1, characterized in that: The anomaly detection indicators include accuracy in three-dimensional coordinates, PDOP value, ADOP value, GDOP value, HDOP value, number of satellites, and / or positioning error distribution.

4. The method for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes according to claim 1, characterized in that: The asynchronous positioning model combining RTK positioning and TDCP calculates the average value of the TDCP position change error sequence to obtain the system error, and uses the obtained system error to compensate for the positioning result; it also performs autocorrelation analysis on the TDCP position change error sequence to obtain the autocovariance, and uses the obtained autocovariance to predict real-time accuracy.

5. The method for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes according to claim 1, characterized in that: When ground-based augmentation solutions malfunction and the main mode switches from ground-based to satellite-based augmentation, the ambiguity and position information output by ground-based augmentation are combined with the variance and used as virtual observation values ​​according to the prior accuracy to constrain the initialization of satellite-based augmentation, thereby reducing its convergence time. When the main mode switches from satellite-based to ground-based augmentation, the ambiguity and position information output by satellite-based augmentation are combined with the variance and used as prior information to constrain the initialization of ground-based augmentation, thereby reducing its convergence time.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method for smoothly switching between ground-based and satellite-based augmentation positioning solution modes as described in any one of claims 1 to 5.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method for smoothly switching between ground-based and satellite-based augmentation positioning solution modes as described in any one of claims 1 to 5.

8. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the method for smoothly switching between ground-based and satellite-based augmentation positioning solution modes as described in any one of claims 1 to 5.

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