Method for achieving smooth switching between ground-based and satellite-based positioning solution modes, and device

Abstract

The present invention provides a method for achieving smooth switching between ground-based and satellite-based augmented positioning solution modes, and a device. A user end uses a ground-based augmented positioning solution mode as a primary mode for augmented positioning, determines, according to a preset anomaly detection indicators, whether ground-based augmentation is available, and if unavailable, smoothly switches to satellite-based augmentation; when the primary mode is switched from the ground-based augmentation to the satellite-based augmentation, an asynchronous positioning mode with supplementary time-based cumulative error compensation is used in combination with bias compensation to maintain stable positioning accuracy at the user end, and ground-based augmentation solution information is also used to constrain the satellite-based augmentation, so as to accelerate the convergence speed of the satellite-based augmentation; and when the primary mode is switched from the satellite-based augmentation to the ground-based augmentation, prior information provided by the satellite-based augmentation is used to constrain the ground-based augmentation, so as to improve the restart speed of the ground-based augmentation positioning mode. By means of optimizing switching, the present invention enhances the continuity and smoothness and positioning consistency during the switching between the ground-based and satellite-based augmented positioning solution modes, thereby improving the reliability of the Beidou augmented positioning technology.

Description

Method and device for realizing smooth switching of ground-based and satellite-based positioning solution modes TECHNICAL FIELD

[0001] The present application belongs to the field of GNSS satellite positioning technology, and particularly relates to a technical scheme for realizing smooth switching of ground-based and satellite-based positioning solution modes. BACKGROUND

[0002] At present, GNSS satellites, such as Beidou, develop rapidly in technology, but some subdivided fields still need continuous improvement, and the problem of continuous smooth switching of ground-based and satellite-based augmentation is an important part. The following specifically introduces the related prior art status.

[0003] 1. Beidou ground-based augmentation

[0004] The Beidou ground-based augmentation system is a technology for improving the positioning accuracy and reliability of the Beidou satellite navigation system. The Beidou ground-based augmentation system forms a network by deploying a large number of monitoring stations on the ground, receives Beidou satellite observation data, processes high-precision positioning service information, and provides augmentation services through a ground broadcasting network to improve the positioning and navigation service performance of ground users, and can achieve centimeter-level or even millimeter-level positioning accuracy.

[0005] 2. Beidou satellite-based precise point positioning (PPP)

[0006] The Beidou satellite-based augmentation is a technology for improving the positioning accuracy of ground user terminals by deploying geostationary orbit satellites (GEO) in space to broadcast real-time differential correction information, including satellite orbit, satellite clock error, and atmospheric delay. The Beidou satellite-based precise point positioning service is broadcast through B2b signals, covering China and surrounding areas, and providing free augmentation positioning services.

[0007] 3. Beidou ground-satellite integrated augmentation

[0008] The Beidou ground-based augmentation system can achieve instantaneous convergence, and the convergence accuracy can reach centimeter level, but it depends on dense reference stations and ground communication networks, especially when facing a large number of users, which may cause network stability to decline. The Beidou satellite-based PPP augmentation service does not depend on the ground communication network, only needs a global sparse station network, but needs tens of minutes to converge. Therefore, the ground-based augmentation system and the satellite-based augmentation system have complementarity, and the realization of satellite-ground integrated augmentation can significantly improve the augmentation service efficiency, and the direct hard switching between the two will cause the positioning result to jump, which seriously affects the reliability and stability of the user's augmented positioning. SUMMARY

[0009] In view of the problem of continuous smooth switching of ground-based and satellite-based augmentation, the present application provides a technical scheme for realizing smooth switching of ground-based and satellite-based positioning solution modes.

[0010] In order to achieve the above object, the technical scheme of the present application is a method for realizing smooth switching of ground-based and satellite-based enhanced positioning calculation modes, wherein the user end takes the ground-based enhanced positioning calculation mode as the main mode of enhanced positioning, judges whether the ground-based enhancement is available according to a pre-set abnormal situation detection index, starts the satellite-based enhanced positioning mode if the ground-based enhancement is not available, and smoothly switches to the satellite-based enhancement.

[0011] When the main mode is switched from the ground-based enhancement to the satellite-based enhancement, an asynchronous positioning mode with additional time cumulative error compensation is adopted, the deviation compensation is combined to maintain the positioning accuracy of the user end stable, and the ground-based enhancement calculation information is combined to constrain the satellite-based enhancement, so as to accelerate the convergence speed of the satellite-based enhancement.

[0012] When the main mode is switched from the satellite-based enhancement to the ground-based enhancement, the prior information provided by the satellite-based enhancement is used to constrain the ground-based enhancement, so as to improve the restart speed of the ground-based enhancement positioning mode.

[0013] Moreover, the positioning result of the ground-based enhancement is fitted with user motion trajectory data, the fitting parameters are taken as the pre-set abnormal situation detection index, and the positioning quality is comprehensively evaluated in combination with other abnormal situation detection indexes.

[0014] Moreover, the abnormal situation detection index includes the in-3D-coordinate compliance accuracy, PDOP value, ADOP value, GDOP value, HDOP value, satellite quantity and / or positioning error distribution.

[0015] Moreover, when the main mode is switched from the ground-based enhancement to the satellite-based enhancement, a TDCP time cumulative error compensation mode is used to construct an asynchronous positioning model combining RTK positioning and TDCP; when the main mode is switched from the ground-based enhancement to the satellite-based enhancement, a consistency judgment test is performed on the positioning accuracy of the ground-based enhancement and the satellite-based enhancement, and when the positioning result accuracy of the two calculation modes is consistent, the switching from the ground-based enhancement positioning to the satellite-based enhancement positioning is performed, so as to realize smooth switching.

[0016] Moreover, 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, compensates the positioning result by using the obtained system error; and performs autocorrelation analysis on the TDCP position change error sequence to obtain the autocovariance, and performs real-time accuracy prediction by using the obtained autocovariance.

[0017] Moreover, when the ground-based enhancement calculation is abnormal, the main mode is switched from the ground-based enhancement to the satellite-based enhancement, the ambiguity and position information output by the ground-based enhancement are combined with the variance, the prior accuracy is taken as the virtual observation value to constrain the satellite-based enhancement initialization, and the convergence time is reduced; when the main mode is switched from the satellite-based enhancement to the ground-based enhancement, the ambiguity and position information output by the satellite-based enhancement are combined with the variance as the prior information to constrain the ground-based enhancement initialization, and the convergence time is reduced.

[0018] In another aspect, the present application also provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes as described above when executing the program.

[0019] In another aspect, the present application also provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the method for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes as described above.

[0020] In another aspect, the present application also provides a computer program product comprising a computer program, wherein the computer program, when executed by a processor, implements the method for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes as described above.

[0021] The present application provides a technical solution for smoothly switching between ground-based and satellite-based augmentation positioning calculation modes on the terminal side. Considering that the ground-based and satellite-based augmentation positioning calculation modes have complementary advantages in complex environments, but the process of switching between the two modes has the problems of result jump, and the high precision of ground-based augmentation is not fully utilized, which seriously affects the high precision, continuity and consistency of the service, thereby reducing the user experience. To solve this problem, when switching from ground-based augmentation to satellite-based augmentation, the present application first uses an asynchronous positioning method with additional time accumulation error compensation, deviation compensation, and precision consistency determination method to reduce the precision loss caused by system switching, and at the same time, uses the high-precision position and ambiguity information provided by ground-based augmentation to constrain satellite-based augmentation, reducing the convergence time of satellite-based augmentation. When switching from satellite-based augmentation to ground-based augmentation, the present application uses the position information provided by satellite-based augmentation to constrain ground-based augmentation, significantly shortening the re-initialization time of the ground-based augmentation positioning calculation mode. When the performance of a single augmentation system is unstable, the present application optimizes the switching method to improve the continuous smoothness and positioning consistency of the ground-based and satellite-based augmentation positioning calculation mode switching, thereby improving the reliability of the Beidou augmentation positioning technology, and has practicality.

[0022] The present application provides a Beidou satellite-ground-based augmentation smooth switching technical solution, which supports in areas where ground facilities are weak and augmentation services are frequently switched, and realizes consistent high-precision positioning performance in the whole region.

[0023] The present application has the advantages of simple and convenient implementation, strong practicability, solving the problems of low practicability and inconvenience in actual application of related technologies, improving user experience, and having important market value. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 is a schematic diagram of an embodiment of the present application.

[0025] Figure 2 is a scene diagram of the seamless switching method of the satellite-based / terrestrial-based enhanced service according to the embodiment of the present application.

[0026] Figure 3 is a diagram of the positioning accuracy of the TDCP changing with time according to the embodiment of the present application.

[0027] Figure 4 is a diagram of the positioning error sequence of the PPP / TDCP according to the embodiment of the present application.

[0028] Figure 5 is a diagram of the physical structure of the electronic device according to the embodiment of the present application. Embodiment of the present application

[0029] The technical solutions of the present application are described in detail below with reference to the accompanying drawings and embodiments.

[0030] As shown in Figure 1, the embodiment of the present application requires the user terminal to take the terrestrial-based enhanced positioning solution mode as the main mode of enhanced positioning, to judge whether the terrestrial-based enhancement is available according to the pre-set abnormal situation detection index, to start the satellite-based enhanced positioning mode if it is not available, to smoothly switch to the satellite-based enhancement, and to take it as the output solution. In the specific implementation, the user terminal can take the Beidou terrestrial-based enhanced positioning solution as the main mode, take the satellite-based enhanced positioning solution mode as the auxiliary mode, and take the main mode positioning result as the system output solution. Once the user terminal finds that the terrestrial-based enhancement signal is missing or other abnormal situations through the pre-set detection index, the accuracy of the main mode positioning result is abnormal, and the system will start the satellite-based enhanced positioning solution mode.

[0031] When the positioning mode is switched from the terrestrial-based enhancement to the satellite-based enhancement, the asynchronous positioning method with additional time accumulation error compensation and the bias compensation method are used to maintain the positioning accuracy of the user terminal stable, and the satellite-based enhancement is constrained in combination with the terrestrial-based enhancement solution information to accelerate the convergence speed of the satellite-based enhancement.

[0032] Further, the present application proposes that when the solution mode is switched from the terrestrial-based enhancement to the satellite-based enhancement, the asynchronous positioning method with additional time accumulation error compensation and the bias compensation method are used to maintain the positioning accuracy of the user terminal to the maximum extent, the satellite-based enhancement is constrained by using the high-precision position and ambiguity information provided by the terrestrial-based enhancement before the solution is abnormal to reduce the convergence time of the satellite-based enhancement; the positioning accuracy of the terrestrial-based enhancement and the satellite-based enhancement is judged and tested for consistency, and when the positioning result accuracy of the two solution modes is consistent, the terrestrial-based enhancement is switched to the satellite-based enhancement, so as to realize smooth switching.

[0033] When the main mode is switched from the satellite-based enhancement to the terrestrial-based enhancement, the high-precision position and ambiguity information provided by the satellite-based enhancement mode is used to constrain the terrestrial-based enhancement mode to accelerate the re-initialization of the terrestrial-based enhancement mode. In the specific implementation, the re-initialization speed of the terrestrial-based enhancement positioning mode can be improved by using the high-precision position and ambiguity information provided by the satellite-based enhancement to constrain the terrestrial-based enhancement.

[0034] Further implementation manners are provided as follows:

[0035] 1. Abnormal situation detection index of ground-based enhancement and satellite-based enhancement

[0036] First, the positioning results of the ground-based enhancement solution mode and the satellite-based enhancement solution mode are fitted with user motion trajectory data; then, by using a weighted average method, combined with multiple indexes such as fitting parameters and internal consistency accuracy STD, and by considering factors such as PDOP value, ADOP value, GDOP value, HDOP value, and satellite number, the positioning quality is comprehensively evaluated. In determining the weights of the indexes, a machine learning method is preferably used to finely control the influence of each factor, to ensure that the comprehensive index can accurately integrate each factor, and to obtain an abnormal situation detection index, thereby optimizing the performance of the positioning system and the user experience.

[0037] The embodiment further proposes to determine the abnormal situation detection index for the ground-based enhancement positioning mode and the satellite-based enhancement positioning mode at the same time, specifically including the following steps:

[0038] The historical positioning results of the ground-based enhancement and the satellite-based enhancement are fitted with user motion trajectory data respectively, and the user historical motion trajectory data is taken as the network training data set of machine learning, and the fitting parameters are taken as the pre-set abnormal situation detection index. If there is a large difference in the user trajectory, it is determined to be abnormal.

[0039] The three-dimensional coordinate inner compliance accuracy, PDOP value, ADOP value, GDOP value, HDOP value, VDOP value, satellite number and / or positioning error distribution of the ground-based augmentation positioning mode and the satellite-based augmentation positioning mode are calculated, and these indexes are taken as abnormal situation detection indexes, if the indexes exceed the threshold value, it is determined that it is abnormal. Wherein, PDOP (Position Dilution of Precision) is a three-dimensional precision factor, which represents the sparsity of position accuracy, and comprehensively considers the accuracy of three-dimensional position (longitude, latitude, height) positioning. The lower the PDOP value is, the higher the positioning accuracy is. HDOP (Horizontal Dilution of Precision) is a horizontal precision factor, which represents the sparsity of horizontal accuracy, and only considers the accuracy of two-dimensional plane (longitude and latitude) positioning. The lower the HDOP value is, the higher the horizontal positioning accuracy is. VDOP (Vertical Dilution of Precision) is a vertical geometric precision factor, which represents the sparsity of vertical accuracy, and focuses on the accuracy of height (vertical direction) positioning. The lower the VDOP value is, the higher the vertical positioning accuracy is. TDOP (Time Dilution of Precision) is a time precision factor, which represents the sparsity of time accuracy. The lower the TDOP value is, the higher the time positioning accuracy is. GDOP (Geometric Dilution of Precision) is a geometric precision factor, which comprehensively considers the accuracy sparsity of position, time and height. GDOP is a more comprehensive index, which combines the influence of all dimensions together. ADOP (Ambiguity Dilution of Precision) is an ambiguity precision factor, which is an easy-to-calculate scalar diagnostic method, used to measure the inherent model strength of successful ambiguity resolution.

[0040] In specific implementation, the preferred implementation mode for recommendation includes, first constructing the parameter precision matrix D as:

[0041]

[0042] In the formula, is an element in the parameter precision matrix, , .

[0043] The calculation formula of the PDOP value is:

[0044]

[0045] The calculation formula of 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:

[0052]

[0053] Let the real-valued float estimate of the GNSS integer ambiguity vector a obey The formula for calculating the ADOP value is:

[0054]

[0055] In the formula, indicates the ambiguity variance matrix, and n indicates the number of ambiguities, indicates the ambiguity variable, indicates the determinant operation.

[0056] The calculation method of the three-dimensional coordinate internal compliance accuracy index STD is:

[0057]

[0058]

[0059] In the formula, indicates the current position, indicates the predicted position obtained by fitting the user trajectory, indicates the corresponding position difference.

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

[0061] First, in the initialization stage, the average value of the TDCP position change error sequence is calculated to obtain the system error, and the autocorrelation analysis is performed to obtain the autocovariance; then, when the carrier enters the motion stage, the system uses the system error compensation positioning result generated in the last stage and the autocovariance to perform real-time accuracy prediction.

[0062] 3. Precision consistency discrimination criterion for RTK asynchronous positioning and satellite-based augmentation

[0063] The position accuracy of the RTK asynchronous positioning is obtained by using the variance of the RTK output result and the error propagation law, and the position accuracy of the RTK asynchronous positioning and the satellite-based augmentation are consistent when the variances of the two are similar.

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

[0065] The ambiguity and position information output by the ground-based augmentation are combined with the variances thereof as virtual observation values to constrain the satellite-based augmentation system initialization, so that the convergence time is reduced.

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

[0067] The TDCP time accumulation error compensation method is used to construct an asynchronous positioning model of the RTK positioning combined with the TDCP, the mean value of the error sequence of the TDCP position change amount is calculated to obtain the system error, the obtained system error is used to compensate the positioning result, the autocorrelation analysis is performed on the error sequence of the TDCP position change amount to obtain the autocovariance, and the obtained autocovariance is used for real-time accuracy prediction; wherein the TDCP (Time-Difference Carrier-Phase) is a GNSS observation epoch difference carrier phase positioning mode.

[0068] The asynchronous positioning model of the RTK positioning combined with the TDCP is that in the static initialization stage, the RTK positioning mode and the TDCP positioning mode are started at the same time, the system error and the autocovariance of the TDCP are analyzed by using the RTK positioning result; in the motion stage, the positioning result is compensated by using the analysis result of the TDCP in the static initialization stage and real-time accuracy prediction is performed.

[0069] For the purpose of implementation reference, the implementation of the RTK positioning combined with the TDCP is described as follows:

[0070] In the case of a high sampling rate, the atmosphere is constant between adjacent epochs, and for the receiver and the satellite , the carrier observation equation of the TDCP positioning method is:

[0071]

[0072] In the formula, φi is the carrier observation value after the difference between adjacent epochs, is the carrier observation value after the difference between adjacent epochs, is the carrier observation value after the difference between adjacent epochs, is the carrier observation value after the difference between adjacent epochs, is the satellite clock error, is the residual noise term.

[0073] The carrier observation equation of the RTK positioning method is:

[0074]

[0075] In the formula, represents a double difference operator, and respectively represent carrier and pseudo-range observation values; represents a reference satellite of the th baseline; respectively represent common satellites of the th baseline; represents a monitoring station; represents the th reference station; represents a geometric distance of a receiver and a satellite; represents an ionospheric delay, which is considered to be small enough to be ignored after double difference of a short baseline, and which can be eliminated by using a double-frequency ionosphere-free combination in a medium-long baseline; represents a tropospheric delay, which is considered to be small enough to be ignored after double difference of a short baseline, and which can be weakened by using a random walk parameter estimation method in a medium-long baseline or a large height difference; represents a double difference value of a carrier's integer ambiguity; represents a wavelength of the carrier; respectively are measurement noises of the carrier and the pseudo-range. Then, represents a carrier observation value, represents a geometric distance of a receiver and a satellite, represents an ionospheric delay, represents a tropospheric delay, represents a double difference value of a carrier's integer ambiguity, represents a carrier measurement noise, represents a pseudo-range observation value, represents a pseudo-range measurement noise.

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

[0077]

[0078]

[0079]

[0080]

[0081] In the formula, represents a carrier observation value, denotes an error compensation coefficient, denotes a coordinate error, denotes a geometric distance, denotes a receiver clock error, denotes a light speed, denotes a satellite clock error, denotes a tropospheric delay, denotes a measurement noise, denotes a recursive position, denotes an initial position, denotes a recursive value, denotes a residual value, i, n denotes an epoch, denotes a noise matrix, , , denotes a coefficient.

[0082] According to the above accuracy consistency criterion, the RTK asynchronous model positioning result accuracy and the satellite-based augmentation positioning result accuracy are judged, and then it is selected whether the system switching is needed. If the RTK asynchronous model positioning result accuracy is lower than the satellite-based augmentation positioning result accuracy, the satellite-based augmentation is switched to.

[0083] The ambiguity and position information output by the ground-based augmentation positioning solution mode are combined with their variances, and a certain prior accuracy is taken as a virtual observation value to constrain the satellite-based augmentation system initialization, so as to reduce the convergence time.

[0084] The ambiguity prior information constraint equation is:

[0085]

[0086] In the formula, denotes ground-based ambiguity information, denotes satellite-based ambiguity information.

[0087] The position prior information constraint equation is:

[0088]

[0089] In the formula, denotes ground-based position information, denotes satellite-based position information.

[0090] The virtual observation value constraint equation is:

[0091]

[0092] In the formula, denotes a virtual observation equation coefficient matrix, M denotes a virtual observation equation constant matrix, and X denotes ambiguity and position parameters.

[0093] 5. Star-based augmentation accelerates initialization of ground-based augmentation

[0094] According to the switching design of the application, when the ground-based augmentation solution is abnormal, the ground-based augmentation is switched to the star-based augmentation, the ambiguity and position information output by the ground-based augmentation are combined with their variances, and a certain priori accuracy is used as a virtual observation value to constrain the initialization of the star-based augmentation, so as to reduce the convergence time; when the ground-based augmentation is switched to the star-based augmentation, the priori information output by the star-based augmentation is used to constrain the initialization of the ground-based augmentation, so as to reduce the convergence time, including using the ambiguity and position information output by the star-based augmentation combined with their variances as a virtual observation value to constrain the initialization of the ground-based augmentation system, so as to reduce the convergence time.

[0095] The effect of the ground-based and star-based augmentation positioning solution mode smooth switching method proposed in the embodiment is described below through experimental results.

[0096] Referring to FIG. 2, FIG. 2 shows the experimental design and experimental scene. The experimental weather condition is relatively good, the satellite observation environment is open, the experimental scene is set in a school playground, and the experimental equipment includes a mobile trolley carrying a GNSS multi-system satellite receiver and another GNSS multi-system satellite receiver as a reference station.

[0097] FIG. 3 shows the positioning error of the TDCP method proposed in the embodiment of the application in the N / E / U (north, east, and sky) direction with time. FIG. 4 shows the comparison effect of the coordinate positioning error sequence of the PPP / TDCP method. The experimental results show that the TDCP method proposed in the application has a height accuracy better than 10 cm within 3 minutes of signal interruption and a plane accuracy better than 5 cm within 9 minutes. It can also be seen from the experimental results that the positioning accuracy of RTK before signal interruption is higher than that of PPP. After signal interruption, the star-ground integrated system uses TDCP to maintain the positioning accuracy, but the error of TDCP will increase with time, and at a certain time point, the accuracy of TDCP will be consistent with that of PPP, which is the time point of switching between star-based and ground-based augmentation. Before this time point, the accuracy of TDCP is higher than that of PPP, and the star-ground integrated system will use TDCP; and after this time point, the error of TDCP is greater than that of PPP, and the star-ground integrated system will be switched to PPP, achieving the effect of star-ground smooth switching.

[0098] Fig. 5 shows a schematic diagram of an electronic device, as shown in Fig. 5, which can include a processor, a communications interface, a memory and a communications bus, wherein the processor, the communications interface and the memory complete the communication with each other through the communications bus. The processor can call the logical instructions in the memory to execute the method for realizing the smooth switching of the ground-based and satellite-based positioning solution mode. In addition, the logical instructions in the memory described above can be realized in the form of a software functional unit and sold or used as an independent product, and can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product, which is stored in a storage medium, includes a plurality of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes. On the other hand, the present application also provides a computer program product, which includes a computer program, the computer program can be stored on a non-transitory computer readable storage medium, and when the computer program is executed by a processor, the computer can execute the method for realizing the smooth switching of the ground-based and satellite-based positioning solution mode provided by the above-mentioned methods. In another aspect, the present application also provides a non-transitory computer readable storage medium, which stores a computer program, and when the computer program is executed by a processor, it realizes the method for realizing the smooth switching of the ground-based and satellite-based positioning solution mode provided by the above-mentioned methods. The device embodiments described above are only schematic, wherein the units illustrated as separate components can be or can not be physically separated, and the components illustrated as units can be or can not be physical units, i.e. they can be located in one place, or distributed on multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the present embodiment. Those skilled in the art can understand and implement it without creative labor. Through the description of the above embodiments, those skilled in the art can clearly understand that the embodiments can be realized by means of software plus the necessary general hardware platform, and of course, can also be realized by hardware.Based on such understanding, the technical solution described above, essentially or in other words, the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product can be stored in a computer readable storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, and the like, and includes a number of instructions for making a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods described in various embodiments or some parts of the embodiments. Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for some technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for implementing smooth switching between ground-based and satellite-based augmentation positioning solution modes, characterized in that: The user terminal takes the ground-based enhanced positioning mode as the main mode of enhanced positioning, judges whether the ground-based enhancement is available according to the pre-set abnormal situation detection index, and starts the satellite-based enhanced positioning mode if the ground-based enhancement is not available, and smoothly switches to the satellite-based enhancement; When the main mode is switched from the ground-based enhancement to the satellite-based enhancement, an asynchronous positioning mode with additional time cumulative error compensation is adopted, the deviation compensation is combined to maintain the positioning accuracy of the user terminal stable, and the satellite-based enhancement is combined with the ground-based enhancement to speed up the convergence speed of the satellite-based enhancement; When the main mode is switched from the satellite-based enhancement to the ground-based enhancement, the prior information provided by the satellite-based enhancement is used to constrain the ground-based enhancement, and the restart speed of the ground-based enhancement positioning mode is improved.

2. The method of claim 1, wherein: The positioning results of the ground-based enhancement are fitted with user motion trajectory data, and the fitting parameters are taken as the pre-set abnormal situation detection index, which is combined with other abnormal situation detection indexes to comprehensively evaluate the positioning quality.

3. The method of claim 1, wherein: The abnormal situation detection index includes the in-3D coordinate compliance accuracy, PDOP value, ADOP value, GDOP value, HDOP value, satellite number and / or positioning error distribution.

4. The method of claim 1, wherein: When the main mode is switched from the ground-based enhancement to the satellite-based enhancement, a TDCP time cumulative error compensation mode is used to construct an asynchronous positioning model combining RTK positioning and TDCP; when the main mode is switched from the ground-based enhancement to the satellite-based enhancement, a consistency judgment test is performed on the positioning accuracy of the ground-based enhancement and the satellite-based enhancement, and when the positioning result accuracy of the two solving modes is consistent, the ground-based enhancement positioning is switched to the satellite-based enhancement positioning, so as to realize smooth switching.

5. The method of claim 4, wherein: 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 compensates the positioning result by using the obtained system error; the autocorrelation analysis is performed on the TDCP position change error sequence to obtain the autocovariance, and the real-time accuracy prediction is performed by using the obtained autocovariance.

6. The method of claim 1, wherein: When the ground-based enhancement solving is abnormal, the main mode is switched from the ground-based enhancement to the satellite-based enhancement, the ambiguity and position information output by the ground-based enhancement are combined with the variance, and the prior accuracy is taken as the virtual observation value to constrain the satellite-based enhancement initialization, so as to reduce the convergence time; when the main mode is switched from the satellite-based enhancement to the ground-based enhancement, the ambiguity and position information output by the satellite-based enhancement are combined with the variance as the prior information to constrain the ground-based enhancement initialization, so as to reduce the convergence time.

7. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to realize the method for realizing smooth switching of the ground-based and satellite-based enhanced positioning solving modes according to any one of claims 1 to 6.

8. A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to realize the method for realizing smooth switching of the ground-based and satellite-based enhanced positioning solving modes according to any one of claims 1 to 6.

9. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to realize the method for realizing smooth switching of the ground-based and satellite-based enhanced positioning solving modes according to any one of claims 1 to 6.

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