Low-orbit satellite-based differential enhancement method, device, equipment, medium and product

Abstract

The application provides a low-orbit satellite-based differential enhancement method, device, equipment, medium and product, and the method comprises the following steps: acquiring satellite observation data of a global navigation satellite system, satellite observation data of a low-orbit satellite and satellite mixed ephemeris of the global navigation satellite system and the low-orbit satellite received by a continuous operation reference station network in real time; forming a baseline by taking two stations as a group according to the second data, so as to obtain a triangulation network baseline; sequentially constructing double-difference equations of satellites of the global navigation satellite system and the low-orbit satellite according to the triangulation network baseline and the first data; performing ambiguity calculation according to the double-difference equations, so as to obtain a fixed solution of ambiguity of the global navigation satellite system and the low-orbit satellite; substituting the fixed solution of ambiguity into an observation equation, so as to obtain baseline atmosphere; and generating a user position subjected to differential enhancement according to the baseline atmosphere and a user request. In the application, the low-orbit satellite and the global navigation satellite system data are combined for ground-based differential enhancement high-precision calculation, so that the calculation efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of ground-based differential augmentation technology, and more particularly to a differential augmentation method, apparatus, equipment, medium, and product based on low-Earth orbit satellites. Background Technology

[0002] Low Earth Orbit (LEO) satellites operate in orbits approximately 500 to 2000 kilometers above the Earth's surface. Compared to traditional medium and high Earth orbit (MEO) satellites, LEO satellites orbit at a lower altitude, resulting in more frequent coverage of ground signals and thus providing higher temporal resolution and faster update rates. Furthermore, LEO satellites have shorter signal propagation delays, making them particularly suitable for real-time, high-precision positioning in highly dynamic environments. Additionally, due to their lower orbits, there are typically a larger number of LEO satellites, forming a constellation network that can provide continuous global service. Combining LEO satellites with traditional Global Navigation Satellite Systems (GNSS) can further improve positioning accuracy and reliability. This fusion approach enhances positioning accuracy, especially in areas where traditional GNSS signals are weak or lost, significantly improving the reliability and accuracy of the positioning system.

[0003] However, in existing technologies, LEO satellite augmentation positioning often uses it as a satellite-based augmentation information broadcasting platform without integrating LEO satellite data itself with GNSS data processing. In the field of ground-based augmentation positioning, the introduction of LEO satellite data has not been considered, and conventional GNSS processing methods cannot adapt to the characteristics of LEO satellites, such as low orbit, rapid changes, and large number, making it difficult to meet the needs of high-precision navigation and positioning. Summary of the Invention

[0004] This invention provides a differential augmentation method, apparatus, device, medium, and product based on low-Earth orbit (LEO) satellites to address the problem that existing GNSS processing methods cannot adapt to the characteristics of LEO satellites, such as low orbits, rapid changes, and large numbers, making it difficult to meet the requirements for high-precision navigation and positioning.

[0005] To solve the above-mentioned technical problems, the present invention is implemented as follows:

[0006] In a first aspect, embodiments of the present invention provide a differential enhancement method based on low-Earth orbit satellites, comprising:

[0007] Acquire satellite observation data of the Global Navigation Satellite System (GNSS), satellite observation data of low-Earth orbit (LEO) satellites, and hybrid ephemeris data of GNSS and LEO satellites from a continuously operating reference station network in real time;

[0008] The satellite observation data of the global navigation satellite system and the satellite observation data of the low-orbit satellite are read according to the epoch on the satellite hybrid ephemeris to obtain the first data, and the position information of each station in the continuously operating reference station network is read from the database as the second data;

[0009] Based on the triangulation grouping algorithm, the baselines of the triangulation network are obtained by forming baselines from pairs of stations in the continuously operating reference station network according to the second data.

[0010] Based on the triangulation baseline and the first data, the non-difference equations, single-difference equations, and double-difference equations of the satellites of the global navigation satellite system, as well as the non-difference equations, single-difference equations, and double-difference equations of the low-Earth orbit satellites, are constructed sequentially.

[0011] Ambiguity calculations are performed based on the double-difference equations of the satellites of the Global Navigation Satellite System and the double-difference equations of the low-Earth orbit satellites to obtain the fixed ambiguity solutions of the Global Navigation Satellite System and the low-Earth orbit satellites.

[0012] Substituting the fixed ambiguity solutions of the global navigation satellite system and the low-Earth orbit satellites into the pre-set observation equations, the baseline atmospheric values ​​of the troposphere and ionosphere corresponding to the fixed solutions of each satellite are obtained.

[0013] Based on the baseline atmosphere and the user request, a differentially enhanced user location is generated.

[0014] Optionally, the satellite hybrid ephemeris of the global navigation satellite system and the low-Earth orbit satellites includes: the orbit and clock information of the global navigation satellite system and the low-Earth orbit satellites.

[0015] Optionally, the first data is obtained by reading and matching the satellite observation data of the Global Navigation Satellite System and the satellite observation data of the low-Earth orbit satellites on the satellite hybrid ephemeris according to epochs, including:

[0016] Based on the epoch check, the newly added satellite observation data of the Global Navigation Satellite System and the satellite observation data of low-Earth orbit satellites at the current epoch are read to obtain the first data.

[0017] Optionally, the location information of each station in the continuously operating reference station network includes at least one of the following: the longitude, latitude, and elevation of the station.

[0018] Optionally, the step of calculating ambiguity based on the double-difference equations of the satellites of the Global Navigation Satellite System and the double-difference equations of the low-Earth orbit satellites to obtain the fixed ambiguity solution of the Global Navigation Satellite System and the fixed ambiguity solution of the low-Earth orbit satellites includes:

[0019] Based on the double difference equation of the satellites of the global navigation satellite system, ambiguity search is performed using wide-lane smoothing window and narrow-lane smoothing window to obtain the fixed ambiguity solution of the global navigation satellite system.

[0020] The dual-frequency ionospheric velocity of the low-Earth orbit (LEO) satellite is calculated based on satellite observation data. The ionospheric fitting residual is determined based on the dual-frequency ionospheric velocity and the fitted ionospheric velocity. A quality analysis is performed on the ionospheric fitting residual, and the set of epochs with the best data quality is selected as the optimal fitting epoch. The size of the ambiguity smoothing window is set based on the optimal fitting epoch, and an ambiguity search is performed based on the size of the ambiguity smoothing window to obtain the fixed ambiguity solution for the LEO satellite.

[0021] Optionally, the step of substituting the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-Earth orbit satellites back into the observation equations to obtain the baseline atmosphere of the troposphere and ionosphere corresponding to the fixed solutions of each satellite includes:

[0022] Substituting the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-Earth orbit satellite back into the observation equation, we obtain the tropospheric and ionospheric values ​​corresponding to the fixed solutions of each satellite.

[0023] A loop test is performed on the atmosphere and ambiguity of the triangulation baseline. The atmosphere that passes the loop test is stored in an atmospheric structure. The atmospheric structure integrates the tropospheric and ionospheric values ​​corresponding to the fixed solutions of each satellite and generates the baseline atmosphere corresponding to the tropospheric and ionospheric values ​​of the fixed solutions of each satellite.

[0024] Secondly, embodiments of the present invention provide a differential enhancement device based on low-Earth orbit satellites, comprising:

[0025] The acquisition module is used to acquire satellite observation data of the Global Navigation Satellite System (GNSS), satellite observation data of low-Earth orbit (LEO) satellites, and hybrid ephemeris data of GNSS and LEO satellites received in real time from the continuously operating reference station network.

[0026] The first processing module is used to read satellite observation data of the global navigation satellite system and satellite observation data of low-orbit satellites according to the epoch on the satellite hybrid ephemeris to obtain first data, and to read the location information of each station in the continuously operating reference station network from the database as second data;

[0027] The second processing module is used to form a baseline by combining two stations in the continuously running reference station network according to the second data based on the triangulation grouping network algorithm, and obtain the triangulation network baseline.

[0028] The third processing module is used to sequentially construct, based on the triangulation baseline and the first data, the non-difference equations, single-difference equations, and double-difference equations of the satellites of the global navigation satellite system, as well as the non-difference equations, single-difference equations, and double-difference equations of the low-orbit satellites.

[0029] The fourth processing module is used to perform ambiguity calculations based on the double-difference equations of the satellites of the global navigation satellite system and the double-difference equations of the low-orbit satellites, so as to obtain the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-orbit satellites.

[0030] The fifth processing module is used to substitute the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-orbit satellite into the pre-set observation equation to obtain the baseline atmosphere of the troposphere and ionosphere corresponding to the fixed solution of each satellite.

[0031] The sixth processing module is used to generate a differentially enhanced user location based on the baseline atmosphere and the user request.

[0032] Thirdly, embodiments of the present invention provide an electronic device, including a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the steps in the differential augmentation method based on low-Earth orbit satellites as described in any one of the first aspects.

[0033] Fourthly, embodiments of the present invention provide a readable storage medium storing a program or instructions that, when executed by a processor, implement the steps in the differential augmentation method based on low-Earth orbit satellites as described in any one of the first aspects.

[0034] Fifthly, embodiments of the present invention provide a computer program product including computer instructions that, when executed by a processor, implement the steps in the differential augmentation method based on low-Earth orbit satellites as described in any one of the first aspects.

[0035] In this invention, satellite observation data from the Global Navigation Satellite System (GNSS), low-Earth orbit (LEO) satellites, and hybrid ephemeris data of the GNSS and LEO satellites are acquired in real time from a continuously operating reference station network. Based on second data, two stations are paired to form a baseline, resulting in a triangular network baseline. Based on the triangular network baseline and the first data, double-difference equations for the GNSS satellites and LEO satellites are constructed sequentially. Ambiguity calculations are performed based on the double-difference equations to obtain fixed ambiguity solutions for the GNSS and LEO satellites. These fixed ambiguity solutions are substituted into the observation equations to obtain the baseline atmosphere. Based on the baseline atmosphere and the user request, a user position enhanced by differential positioning is generated. By fusing data from the Global Navigation Satellite System (GNSS) with data from low-Earth orbit (LEO) satellites, and considering the characteristics of LEO satellites, this method reads only the observed and shared LEO satellites. An inter-epoch check method is used for ephemeris reading, only reading historically unread satellite ephemeris to improve the efficiency of current epoch calculation. This achieves ground-based differential augmentation for high-precision calculation of LEO satellite GNSS data, improving calculation efficiency and solving the problem that existing GNSS processing methods cannot adapt to the characteristics of LEO satellites—low orbit, rapid changes, and large numbers—making it difficult to meet the requirements of high-precision navigation and positioning. Attached Figure Description

[0036] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0037] Figure 1 This is a flowchart of a differential enhancement method based on low-Earth orbit satellites provided in an embodiment of the present invention;

[0038] Figure 2 This is a flowchart illustrating the overall process of a differential augmentation method based on low-Earth orbit satellites provided in an embodiment of the present invention.

[0039] Figure 3 This is a low-orbit satellite simulation data trajectory diagram provided in an embodiment of the present invention;

[0040] Figure 4 This is a schematic diagram of the structure of a differential augmentation device based on a low-Earth orbit satellite provided in an embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Please refer to Figure 1 This invention provides a differential augmentation method based on low-Earth orbit satellites, comprising:

[0044] Step 11: Acquire satellite observation data of the Global Navigation Satellite System (GNSS), satellite observation data of low-Earth orbit (LEO) satellites, and hybrid ephemeris data of GNSS and LEO satellites received in real time from the continuously operating reference station network;

[0045] Please refer to Figure 2 In this embodiment of the invention, the receiver of the Continuous Operating Reference Station Network (CORS) receives positioning signal data from Global Navigation Satellite System (GNSS) satellites in real time, and also receives positioning signal data from Low Earth Orbit Satellite (LEO) satellites. The LEO satellite simulation data trajectory diagram is shown below. Figure 3 As shown, the simulated data trajectory of a low-Earth orbit satellite over 10 minutes is displayed. In addition, the receiver acquires hybrid ephemeris information from GNSS and LEO satellite data. Due to their lower orbital altitude, LEO satellites can provide auxiliary data in locations with weak GNSS signals or where antenna obstruction occurs, enhancing signal coverage and availability. By merging LEO satellite data with GNSS data, the system can maintain positioning accuracy even when signals are interfered with. Furthermore, the hybrid ephemeris combines information from different satellite systems, helping to eliminate differences in the links between their respective systems, reducing positioning errors, improving overall positioning accuracy, and providing sufficient basic data support for subsequent positioning calculations.

[0046] In this embodiment of the invention, optionally, the satellite hybrid ephemeris of the global navigation satellite system and the low-Earth orbit satellite includes: the orbit and clock information of the global navigation satellite system and the low-Earth orbit satellite.

[0047] In this embodiment of the invention, the hybrid ephemeris information combines the orbit and clock information of GNSS and low-Earth orbit satellites, enabling the receiver to process observation data from different types of satellites at the same time, providing basic data support for subsequent high-precision calculation of LEO and GNSS data.

[0048] Step 12: Read the satellite observation data of the global navigation satellite system and the satellite observation data of the low-orbit satellite according to the epoch on the satellite hybrid ephemeris to obtain the first data, and read the position information of each station in the continuously operating reference station network from the database as the second data;

[0049] Please refer to Figure 2 In this embodiment of the invention, reading by epoch ensures that the system reflects the latest satellite status in a dynamic environment, improving data accuracy. Especially in highly dynamic or rapidly changing scenarios, high-quality first data provides accurate input for satellite positioning algorithms, helping to reduce potential errors in the solution process and enhance positioning reliability.

[0050] In this embodiment of the invention, optionally, the step of reading and matching the satellite observation data of the Global Navigation Satellite System and the satellite observation data of low-Earth orbit satellites on the satellite hybrid ephemeris to obtain the first data includes:

[0051] Based on the epoch check, the newly added satellite observation data of the Global Navigation Satellite System and the satellite observation data of low-Earth orbit satellites at the current epoch are read to obtain the first data.

[0052] In this embodiment of the invention, considering the large amount of data from low-Earth orbit (LEO) satellites, a single-epoch dynamic space allocation method is adopted. By only reading the LEO satellite observation data observable at the current epoch, the selection and calculation of data are optimized, thereby improving the efficiency of LEO satellite calculation. Furthermore, in the ephemeris reading, an inter-epoch check is adopted, that is, to identify whether there are any new satellites before or after the epoch, and only read the ephemeris of the new satellites. This ensures that only historical ephemeris that have not yet been processed are read during each calculation, thereby avoiding repeated reading of LEO satellite ephemeris, improving the calculation efficiency of the current LEO satellite epoch, and optimizing the data processing flow.

[0053] In this embodiment of the invention, optionally, the location information of each station in the continuously operating reference station network includes at least one of the following: the longitude, latitude, and elevation of the station.

[0054] In this embodiment of the invention, accurate station location information provides a high-precision reference for subsequent baseline calculation, improving the accuracy of user positioning. By using elevation and latitude / longitude information, interference caused by terrain changes or equipment errors is eliminated, improving data reliability. Obtaining the longitude, latitude, and elevation information of the stations provides a data source for the fusion of various types of data, improving the overall performance of the data.

[0055] Step 13: Based on the triangulation grouping network algorithm, the two stations in the continuously operating reference station network are combined into a baseline according to the second data to obtain the triangulation network baseline;

[0056] Please refer to Figure 2 In this embodiment of the invention, the Delaunay triangulation algorithm is used to construct the spatial relationships of each station, forming multiple triangular networks. In each triangular network, every two adjacent stations are connected to form a baseline. Each triangular network contains three baselines. Each pair of baselines in the CORS station network can be used as a double-difference filter for solution. By constructing efficient spatial relationships of the stations, the organization of data processing is improved, which is helpful for subsequent data calculation and analysis. By using each pair of baselines in the CORS station network as a double-difference filter, accurate solution of GNSS and LEO signals is achieved, thereby eliminating common error sources such as the ionosphere and troposphere, and thus obtaining more accurate positioning information.

[0057] Step 14: Construct the non-difference equations, single-difference equations, and double-difference equations for satellites of the Global Navigation Satellite System, as well as the non-difference equations, single-difference equations, and double-difference equations for low-Earth orbit satellites, based on the triangulation baseline and the first data.

[0058] Please refer to Figure 2 In this embodiment of the invention, the non-difference, single-difference, and double-difference equations for low-orbit satellites and GNSS satellites are respectively constructed based on the baseline filter obtained from the triangulation baseline.

[0059] Taking LEO as an example, the original LEO observation equation for a single reference station is:

[0060] ;

[0061] Where r, i, and s are the station number, observation frequency, and LEO satellite number, respectively; c is the speed of light; ; and For receiver clock bias and satellite clock bias; For the station Tropospheric error at the location; For the station In satellite Ionospheric errors encountered along the propagation path; The pseudorange hardware delay at the receiver end; For receiver-side phase hardware delay; For pseudorange hardware delay at the satellite end; For satellite-side phase hardware delay; The wavelength of the carrier wave; For ambiguity; and This refers to the observation noise for pseudorange and phase.

[0062] If two reference stations are not far apart, the original observations can be subtracted to form single-difference and double-difference models. The inter-station single-difference model eliminates satellite-end errors and reduces some atmospheric errors, such as LEO satellite orbit, clock bias, hardware delay, and tropospheric and ionospheric errors. The inter-station double-difference model further eliminates receiver-end errors, such as receiver clock bias and receiver hardware delay, and reduces atmospheric errors. In general baseline processing, the double-difference model is often used. Specifically:

[0063] The equation for single-difference observations between stations is:

[0064] ;

[0065] The inter-station double-difference observation equation is:

[0066] ;

[0067] in, It is a double difference operator; It is a single difference operator; These are pseudorange observations; These are phase observations; For the distance of the guard; For receiver clock bias; This is for tropospheric error; B is the ionospheric error; B is the pseudorange bias; b is the phase bias correction. Wavelength; For integer ambiguity; These represent the multipath errors of phase and pseudorange, respectively; superscript For satellite; subscript For base stations; For frequency points.

[0068] In this embodiment of the invention, after adopting the double-difference operator, the double-difference ambiguity term in the carrier observation will not absorb the error related to the receiver, so it still retains the integer characteristic. Fixing it to an integer can further improve the solution accuracy.

[0069] Step 15: Perform ambiguity calculations based on the double-difference equations of the satellites of the Global Navigation Satellite System and the double-difference equations of the low-Earth orbit satellites to obtain the fixed ambiguity solutions of the Global Navigation Satellite System and the low-Earth orbit satellites.

[0070] Please refer to Figure 2In this embodiment of the invention, by constructing a double-difference equation for GNSS and LEO satellites, the influence of the ionosphere and troposphere is eliminated, thereby reducing the error sources in the solution process and improving the reliability of positioning. Furthermore, based on the constructed double-difference equation, ambiguity calculation is performed using the obtained observation data. By obtaining a fixed ambiguity solution, the system can provide accurate and reliable data about the user's location, thus improving the solution accuracy.

[0071] In this embodiment of the invention, optionally, the step of performing ambiguity calculation based on the double-difference equations of the satellites of the Global Navigation Satellite System and the double-difference equations of the low-Earth orbit satellites to obtain the fixed ambiguity solution of the Global Navigation Satellite System and the fixed ambiguity solution of the low-Earth orbit satellites includes:

[0072] Based on the double difference equation of the satellites of the global navigation satellite system, ambiguity search is performed using wide-lane smoothing window and narrow-lane smoothing window to obtain the fixed ambiguity solution of the global navigation satellite system.

[0073] The dual-frequency ionospheric velocity of the low-Earth orbit (LEO) satellite is calculated based on satellite observation data. The ionospheric fitting residual is determined based on the dual-frequency ionospheric velocity and the fitted ionospheric velocity. A quality analysis is performed on the ionospheric fitting residual, and the set of epochs with the best data quality is selected as the optimal fitting epoch. The size of the ambiguity smoothing window is set based on the optimal fitting epoch, and an ambiguity search is performed based on the size of the ambiguity smoothing window to obtain the fixed ambiguity solution for the LEO satellite.

[0074] In this embodiment of the invention, in actual calculations, the ambiguity search for GNSS satellites is often performed using a wide-lane method followed by a narrow-lane method. Because GNSS satellites have high orbits and relatively slow changes, a traditional wide-lane smoothing window is used, where a fixed value is sufficient. However, considering the rapid changes of low-Earth orbit satellites, a fixed window is insufficient to meet the demands of rapid changes. Therefore, the size of the wide-lane smoothing window is dynamically adjusted based on the ionospheric change rate. Specifically:

[0075] First, the total TEC (Electro-Content Tolerance) of the dual-frequency ionosphere for low-Earth orbit satellites is calculated as follows:

[0076] ;

[0077] in, For the epoch number, For frequency, wavelength, For phase observations, N represents ambiguity, and subscripts 1 and 2 represent the first and second frequency points, respectively.

[0078] Taking the difference between epochs of the above equation, we can obtain the ionospheric velocity TECR:

[0079] ;

[0080] Because carrier wave observations have high accuracy, their fitting residuals can be analyzed to determine the data segment with the most stable fluctuations up to the current epoch. Then, the ionospheric velocity can be fitted using least squares to obtain the fitted value. The fitting residual can be obtained by subtracting the fitted value from the ionospheric velocity. : The optimal number of epochs for fitting is determined by selecting the ionospheric fitting residuals from the first n epochs. Perform quality analysis and reduce the first one in sequence. Different quality results are obtained. Among these results, the set of epochs with the best data quality is selected as the optimal fitting epoch window. The first window of epochs is selected for the TCR fitting. Generally, a fitting order of 3 is sufficient to meet the accuracy requirements. The quality of the observed data is judged using the standard deviation.

[0081] ;

[0082] in, , The residuals of the ionosphere fitting. The value is the residual average. To ensure effective fitting, based on experience, the minimum fitting epoch is set to 5, and the upper limit for low-Earth orbit satellites is set to 30 epochs.

[0083] This allows for dynamic setting of the ambiguity smoothing window, thereby fixing the wide-lane ambiguity. Finally, wide-lane constraints are applied to obtain the floating-point ambiguity solution. Finally, a lambda search is used to obtain the fixed ambiguity solution. Specifically, the lambda method first uses integer transformation to linearly transform the floating-point ambiguity and its variance-covariance matrix. While maintaining its integer properties, this reduces the correlation between various parameters. Finally, the optimal integer solution is obtained in the transformed space through enumeration search. This integer transformation is generally called the z-transform, where the variance matrix and real ambiguity before the transformation are... , The transformed variance matrix and real ambiguity are: and Specifically, it can be expressed as: After obtaining the optimal integer solution, it is necessary to confirm the ambiguity, which is generally done using the Ratio value. The sum of squared residuals representing different ambiguity search values ​​is tested using the following formula: ;

[0084] If an incorrect ambiguity exists in the selected ambiguity combination, it will cause the residual to increase. Therefore, when and When significant differences exist, the ambiguity can be considered fixed and accurate, typically with a ratio of 2.0. After obtaining the correct integer value of the ambiguity, the following formula can be used to update other parameters to obtain a fixed solution for the ambiguity:

[0085] ;

[0086] in, and Representing floating-point and fixed solutions for ambiguity; Let x and N be the covariance matrices. Let N be the variance matrix.

[0087] In this embodiment of the invention, a unique ambiguity maintenance algorithm is designed for low-Earth orbit (LEO) satellites. Combined with ionospheric change rate information, the wide-lane smoothing window is adaptively adjusted to quickly fix the ambiguity, effectively introducing LEO satellites into ground-based augmentation services and realizing high-precision ground-based differential augmentation solution of LEO satellites and GNSS data.

[0088] Step 16: Substitute the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-orbit satellite into the pre-set observation equation to obtain the baseline atmosphere of the troposphere and ionosphere corresponding to the fixed solution of each satellite;

[0089] In this embodiment of the invention, optionally, the step of substituting the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-Earth orbit satellite back into the observation equation to obtain the baseline atmosphere of the troposphere and ionosphere corresponding to the fixed solutions of each satellite includes:

[0090] Substituting the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-Earth orbit satellite back into the observation equation, we obtain the tropospheric and ionospheric values ​​corresponding to the fixed solutions of each satellite.

[0091] A loop test is performed on the atmosphere and ambiguity of the triangulation baseline. The atmosphere that passes the loop test is stored in an atmospheric structure. The atmospheric structure integrates the tropospheric and ionospheric values ​​corresponding to the fixed solutions of each satellite and generates the baseline atmosphere corresponding to the tropospheric and ionospheric values ​​of the fixed solutions of each satellite.

[0092] Please refer to Figure 2In this embodiment of the invention, the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-Earth orbit satellite are substituted back into the observation equation to obtain the tropospheric and ionospheric values ​​corresponding to the fixed solutions of each satellite. After each baseline is solved, a loop check is performed on the baseline atmosphere and ambiguity of the triangulation network. The loop check cross-validates the baseline data, which helps to ensure the reliability of the atmospheric values ​​and ambiguity solutions used and reduces the positioning deviation caused by data errors. The atmosphere that passes the loop check is stored in the atmospheric structure and transmitted to the downstream atmospheric generation module. This atmospheric structure integrates the tropospheric and ionospheric values ​​corresponding to each satellite.

[0093] Step 17: Generate the differentially enhanced user location based on the baseline atmosphere and the user request.

[0094] In this embodiment of the invention, the baseline atmospheric data is interpolated to the user's location using a differential generation module to generate LEO / GNSS enhanced differential data. Specifically:

[0095] Assuming there are three reference stations A, B, and C in the baseline network, and using A as the reference station for station-satellite double difference analysis, we obtain:

[0096] ;

[0097] ;

[0098] in, , It is a comprehensive analysis of various distance-related errors on the baseline of the base station; , These are phase observations on the baseline of the base station; , It is the satellite-to-ground distance on the baseline of the base station; For satellite wavelength; and The carrier phase ambiguity on the baseline of the reference station; satellite i is the reference satellite; satellite j is a non-reference satellite.

[0099] By transforming the above formula, we can obtain:

[0100] ;

[0101] ;

[0102] Similarly, the virtual reference station V and the main base station A also satisfy the following:

[0103] ;

[0104] in, Interpolation can be performed based on the spatial relationship between the virtual reference station and each base station. and We obtain; considering that the coordinates of the VRS station and the main reference station A are known, and the coordinates of satellite i and satellite j are also known, then... This is also known; therefore, expanding the above equation, we can obtain:

[0105] ;

[0106] Expanding the above equation further, we get:

[0107] ;

[0108] Assume that the integer ambiguity of the VRS station and the main reference station A is equal for each satellite, that is: ;

[0109] So: ;

[0110] Based on the above formula, we can obtain a set of virtual observations for the i-th and j-th satellites of the VRS station:

[0111]

[0112]

[0113] Once the above process is completed, virtual observation data for the specified area can be generated, thereby generating user location differential, which means that the ground-based augmentation differential service for GNSS / LEO is completed.

[0114] In this embodiment of the invention, satellite observation data of the Global Navigation Satellite System (GNSS), satellite observation data of low-Earth orbit (LEO) satellites, and hybrid ephemeris data of the GNSS and LEO satellites are acquired in real time from a continuously operating reference station network. Based on second data, two stations are paired to form a baseline, resulting in a triangular network baseline. Based on the triangular network baseline and the first data, double-difference equations for the GNSS satellites and LEO satellites are constructed sequentially. Ambiguity calculations are performed based on the double-difference equations to obtain fixed ambiguity solutions for the GNSS and LEO satellites. These fixed ambiguity solutions are substituted into the observation equations to obtain the baseline atmosphere. Based on the baseline atmosphere and the user request, a user position enhanced by differential positioning is generated. By fusing data from the Global Navigation Satellite System (GNSS) with data from low-Earth orbit (LEO) satellites, and considering the characteristics of LEO satellites, this method reads only the observed and shared LEO satellites. An inter-epoch check method is used for ephemeris reading, only reading historically unread satellite ephemeris to improve the efficiency of current epoch calculation. This achieves ground-based differential augmentation for high-precision calculation of LEO satellite GNSS data, improving calculation efficiency and solving the problem that existing GNSS processing methods cannot adapt to the characteristics of LEO satellites—low orbit, rapid changes, and large numbers—making it difficult to meet the requirements of high-precision navigation and positioning.

[0115] Please refer to Figure 4 This invention provides a differential augmentation device based on low-Earth orbit satellites, comprising:

[0116] The acquisition module 41 is used to acquire satellite observation data of the Global Navigation Satellite System, satellite observation data of low-Earth orbit satellites, and satellite hybrid ephemeris of the Global Navigation Satellite System and low-Earth orbit satellites received in real time by the continuously operating reference station network.

[0117] The first processing module 42 is used to read satellite observation data of the global navigation satellite system and satellite observation data of low-orbit satellites according to the epoch on the satellite hybrid ephemeris to obtain first data, and to read the location information of each station in the continuously operating reference station network from the database as second data;

[0118] The second processing module 43 is used to form a baseline by combining two stations in the continuously running reference station network according to the second data based on the triangulation grouping network algorithm, and obtain the triangulation network baseline.

[0119] The third processing module 44 is used to sequentially construct the non-difference equations, single-difference equations, and double-difference equations of the satellites of the global navigation satellite system, as well as the non-difference equations, single-difference equations, and double-difference equations of the low-orbit satellites, based on the triangulation baseline and the first data.

[0120] The fourth processing module 45 is used to perform ambiguity calculations based on the double difference equations of the satellites of the global navigation satellite system and the double difference equations of the low-orbit satellites, so as to obtain the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-orbit satellites.

[0121] The fifth processing module 46 is used to substitute the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-orbit satellite into the pre-set observation equation to obtain the baseline atmosphere of the troposphere and ionosphere values ​​corresponding to the fixed solutions of each satellite.

[0122] The sixth processing module 47 is used to generate a differentially enhanced user location based on the baseline atmosphere and the user request.

[0123] The differential augmentation device based on low-Earth orbit satellites provided in this embodiment of the invention can achieve... Figure 1 The various processes implemented in the method embodiments achieve the same technical effect, and will not be described again here to avoid repetition.

[0124] This invention provides an electronic device 50, see [link to relevant documentation]. Figure 5 As shown, Figure 5 This is a schematic diagram of the electronic device 50 according to an embodiment of the present invention, including a processor 51, a memory 52, and a program or instructions stored in the memory 52 and executable on the processor 51. When the program or instructions are executed by the processor, they implement the steps in any of the differential augmentation methods based on low-Earth orbit satellites of the present invention.

[0125] This invention provides a readable storage medium on which a program or instruction is stored. When the program or instruction is executed by a processor, it implements the various processes of the differential augmentation method based on low-Earth orbit satellites as described above, and achieves the same technical effect. To avoid repetition, it will not be described again here.

[0126] This application also provides a computer program product, including computer instructions, which, when executed by a processor, implement the above-described... Figure 1 The various processes of the method embodiments shown can achieve the same technical effect, and will not be described again here to avoid repetition.

[0127] Computer-readable media include both permanent and non-permanent, removable and non-removable media, which can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0128] It should be noted that the collection, gathering, updating, analysis, processing, use, transmission, and storage of user personal information involved in this disclosed technical solution all comply with relevant laws and regulations, are used for legitimate purposes, and do not violate public order and good morals. Necessary measures are taken to prevent unauthorized access to user personal information data and to safeguard user personal information security and network security.

[0129] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0130] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0131] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, 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 is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a service classification device (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0132] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A low earth orbit satellite based differential augmentation method, characterized by, include: Acquire satellite observation data of the Global Navigation Satellite System (GNSS), satellite observation data of low-Earth orbit (LEO) satellites, and hybrid ephemeris data of GNSS and LEO satellites from a continuously operating reference station network in real time; The satellite observation data of the global navigation satellite system and the satellite observation data of the low-orbit satellite are read according to the epoch on the satellite hybrid ephemeris to obtain the first data, and the position information of each station in the continuously operating reference station network is read from the database as the second data; Based on the triangulation grouping algorithm, the baselines of the triangulation network are obtained by forming baselines from pairs of stations in the continuously operating reference station network according to the second data. Based on the triangulation baseline and the first data, the non-difference equations, single-difference equations, and double-difference equations of the satellites of the global navigation satellite system, as well as the non-difference equations, single-difference equations, and double-difference equations of the low-Earth orbit satellites, are constructed sequentially. Ambiguity calculations are performed based on the double-difference equations of the satellites of the Global Navigation Satellite System and the double-difference equations of the low-Earth orbit satellites to obtain the fixed ambiguity solutions of the Global Navigation Satellite System and the low-Earth orbit satellites. Substituting the fixed ambiguity solutions of the global navigation satellite system and the low-Earth orbit satellites into the pre-set observation equations, the baseline atmospheric values ​​of the troposphere and ionosphere corresponding to the fixed solutions of each satellite are obtained. Based on the baseline atmosphere and the user request, generate the differentially enhanced user location; The step of calculating ambiguity based on the double-difference equations of the satellites of the Global Navigation Satellite System and the double-difference equations of the low-Earth orbit satellites to obtain the fixed ambiguity solutions for the Global Navigation Satellite System and the low-Earth orbit satellites includes: Based on the double difference equation of the satellites of the global navigation satellite system, ambiguity search is performed using wide-lane smoothing window and narrow-lane smoothing window to obtain the fixed ambiguity solution of the global navigation satellite system. The dual-frequency ionospheric velocity of the low-Earth orbit (LEO) satellite is calculated based on satellite observation data. The ionospheric fitting residual is determined based on the dual-frequency ionospheric velocity and the fitted ionospheric velocity. A quality analysis is performed on the ionospheric fitting residual, and the set of epochs with the best data quality is selected as the optimal fitting epoch. The size of the ambiguity smoothing window is set based on the optimal fitting epoch, and an ambiguity search is performed based on the size of the ambiguity smoothing window to obtain the fixed ambiguity solution for the LEO satellite.

2. The differential augmentation method based on low-Earth orbit satellites according to claim 1, characterized in that, The hybrid ephemeris of the Global Navigation Satellite System (GNSS) and Low Earth Orbit (LEO) satellites includes the orbit and clock information of the GNSS and LEO satellites. 3.The low earth orbit satellite based differential enhancement method of claim 1, wherein, The satellite observation data of the Global Navigation Satellite System and the satellite observation data of low-Earth orbit satellites collected on the satellite hybrid ephemeris are read and matched according to epoch to obtain the first data, including: Based on the epoch check, the newly added satellite observation data of the Global Navigation Satellite System and the satellite observation data of low-Earth orbit satellites at the current epoch are read to obtain the first data.

4. The differential augmentation method based on low-Earth orbit satellites according to claim 1, characterized in that, The location information of each station in the continuously operating reference station network includes at least one of the following: the longitude, latitude, and elevation of the station. 5.The low earth orbit satellite based differential enhancement method of claim 1, wherein, The process of substituting the fixed ambiguity solutions of the global navigation satellite system and the low-Earth orbit satellites back into the observation equations to obtain the baseline atmosphere of the troposphere and ionosphere corresponding to the fixed solutions of each satellite includes: Substituting the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-Earth orbit satellite back into the observation equation, we obtain the tropospheric and ionospheric values ​​corresponding to the fixed solutions of each satellite. A loop test is performed on the atmosphere and ambiguity of the triangulation baseline. The atmosphere that passes the loop test is stored in an atmospheric structure. The atmospheric structure integrates the tropospheric and ionospheric values ​​corresponding to the fixed solutions of each satellite and generates the baseline atmosphere corresponding to the tropospheric and ionospheric values ​​of the fixed solutions of each satellite.

6. A low earth orbit satellite based differential augmentation apparatus, characterized by, include: The acquisition module is used to acquire satellite observation data of the Global Navigation Satellite System (GNSS), satellite observation data of low-Earth orbit (LEO) satellites, and hybrid ephemeris data of GNSS and LEO satellites received in real time from the continuously operating reference station network. The first processing module is used to read satellite observation data of the global navigation satellite system and satellite observation data of low-orbit satellites according to the epoch on the satellite hybrid ephemeris to obtain first data, and to read the location information of each station in the continuously operating reference station network from the database as second data; The second processing module is used to form a baseline by combining two stations in the continuously running reference station network according to the second data based on the triangulation grouping network algorithm, and obtain the triangulation network baseline. The third processing module is used to sequentially construct, based on the triangulation baseline and the first data, the non-difference equations, single-difference equations, and double-difference equations of the satellites of the global navigation satellite system, as well as the non-difference equations, single-difference equations, and double-difference equations of the low-orbit satellites. The fourth processing module is used to perform ambiguity calculations based on the double-difference equations of the satellites of the Global Navigation Satellite System (GNSS) and the double-difference equations of the low-Earth orbit (LEO) satellites, to obtain fixed ambiguity solutions for the GNSS and LEO satellites. The step of performing ambiguity calculations based on the double-difference equations of the GNSS and LEO satellites to obtain fixed ambiguity solutions for the GNSS includes: performing ambiguity search using wide-lane smoothing windows and narrow-lane smoothing windows based on the double-difference equations of the GNSS satellites to obtain fixed ambiguity solutions for the GNSS; calculating the dual-frequency ionospheric velocity of the LEO satellites based on satellite observation data; determining the ionospheric fitting residual based on the dual-frequency ionospheric velocity and the fitted ionospheric velocity, and performing quality analysis based on the ionospheric fitting residual to select the set of epochs with the best data quality as the optimal fitting epoch; setting the size of the ambiguity smoothing window based on the optimal fitting epoch, and performing ambiguity search based on the size of the ambiguity smoothing window to obtain fixed ambiguity solutions for the LEO satellites. The fifth processing module is used to substitute the fixed ambiguity solution of the global navigation satellite system and the fixed ambiguity solution of the low-orbit satellite into the pre-set observation equation to obtain the baseline atmosphere of the troposphere and ionosphere corresponding to the fixed solution of each satellite. The sixth processing module is used to generate a differentially enhanced user location based on the baseline atmosphere and the user request.

7. An electronic device, comprising: It includes a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the steps in the differential augmentation method based on low-Earth orbit satellites as described in any one of claims 1 to 6.

8. A readable storage medium, characterized by, The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the differential augmentation method based on low-Earth orbit satellites as described in any one of claims 1 to 6.

9. A computer program product, characterized in that, It includes computer instructions that, when executed by a processor, implement the steps in the differential augmentation method based on low-Earth orbit satellites as described in any one of claims 1 to 6.

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