Precise point positioning method and device based on ionospheric penetration point proximity constraint

Abstract

The present application discloses a precise single-point positioning method and device based on the proximity constraint of the ionospheric puncture point, which belongs to the field of satellite navigation technology. The satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content are solved by using satellite ephemeris and original observations; then, adjacent satellites are screened out, and the satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content corresponding to the adjacent satellites are used to establish an ionospheric puncture point proximity function model and a random model; finally, a high-seas precise single-point positioning model based on the proximity constraint of the ionospheric puncture point is constructed. The precise single-point positioning method and device provided by the present application ensure the high-precision PPP positioning performance in the offshore area, shorten the long PPP initialization time, break through the PPP convergence limit, and realize the rapid convergence of PPP in the offshore area. It is suitable for high-precision positioning in the offshore area, and improves the operational efficiency in offshore application fields such as drilling platforms, channel measurement, pipeline laying, and unmanned shipping.

Description

Technical Field

[0001] The present application relates to a precise single-point positioning method and device based on ionospheric puncture point proximity constraints, belonging to the field of satellite navigation technology. Background Art

[0002] Currently, precise point positioning (PPP) is a single-station positioning technology used for global, wide-area positioning, particularly in offshore areas. However, ionospheric delay error is one of the main limitations hindering the continuous improvement of PPP positioning accuracy and convergence performance. Currently, methods for eliminating and suppressing ionospheric delay error can be roughly divided into the following four categories: Method 1: Using an ionospheric elimination combination, which can completely eliminate the impact of ionospheric delay error on PPP positioning methods. Method 2: Using the Klobuchar model to eliminate ionospheric delay error. This method is simple and easy to implement and can effectively eliminate approximately 50% of ionospheric delay error. Method 3: Using the Global Ionosphere Map (GIM) to eliminate ionospheric delay error. This method generates a global ionospheric product based on a sparse global base station network and can typically eliminate approximately 80% of ionospheric delay error. Method 4: Using a local ionospheric model to eliminate ionospheric error. This method is suitable for areas with densely distributed land-based base stations on land or offshore areas and can relatively completely eliminate ionospheric delay error.

[0003] However, the above methods still have many limitations when it comes to dealing with ionospheric delay errors in precise point positioning methods. Method 1 can only obtain floating-point solutions for ambiguities, with positioning accuracy only at the sub-meter level and often a long convergence time. Method 2 has limited ability to eliminate ionospheric delay errors and cannot solve the problems of PPP positioning accuracy and long convergence time. Method 3's global ionospheric grid product has an accuracy of only 1 to 2 TECU. Although this is an improvement over Method 2, the error correction is incomplete and still cannot improve PPP positioning and convergence performance. Method 4 does not have a dense network of land-based reference stations in the open sea, making it impossible to model local ionospheric regions and thus cannot be applied to open sea PPP positioning. Summary of the Invention

[0004] The purpose of this application is to provide a precise single-point positioning method and device based on the proximity constraint of the ionospheric puncture point, which can effectively solve the problem that the ionospheric delay error in the offshore area cannot be accurately corrected, not only ensuring the high-precision PPP positioning performance, but also effectively and significantly shortening the offshore PPP initialization time.

[0005] To achieve the above objectives, the present application provides, in a first aspect, a precise point positioning method based on ionospheric puncture point proximity constraints, comprising:

[0006] Calculate the position coordinates of each satellite and the approximate position coordinates of the receiver through satellite ephemeris and original observations;

[0007] Calculating the ionospheric penetration point position of each satellite based on the above-mentioned satellite position coordinates and the above-mentioned receiver approximate position coordinates;

[0008] Based on the above original observations, the vertical total electron content of the ionosphere of each satellite is obtained by the carrier phase smoothed pseudorange method;

[0009] The satellites are screened to obtain a number of nearby satellites, and then a mathematical model and a stochastic model of the ionospheric piercing point proximity are established based on the ionospheric piercing point positions and the ionospheric vertical total electron content corresponding to the nearby satellites, wherein the nearby satellites are satellites that are close to the ionospheric piercing point;

[0010] Based on the above-mentioned mathematical model of the ionospheric puncture point proximity and the above-mentioned random model, a high-seas precise point positioning model with additional ionospheric delay constraints of the adjacent satellite group is constructed, and precise point positioning of the receiver is achieved through the above-mentioned high-seas precise point positioning model.

[0011] In one embodiment, the raw observations include pseudorange raw observations;

[0012] The calculation of the satellite position coordinates and the receiver approximate position coordinates using the satellite ephemeris and the original observations includes:

[0013] Calculate the satellite position coordinates using the pseudorange original observations and the satellite ephemeris;

[0014] The single point positioning solution is performed using the above pseudo-range original observations to obtain the approximate position coordinates of the receiver.

[0015] In one embodiment, the calculating of the ionospheric penetration point position of each satellite based on the satellite position coordinates and the receiver approximate position coordinates includes:

[0016] Calculating the altitude and azimuth of each satellite based on the satellite position coordinates and the receiver approximate position coordinates;

[0017] The ionospheric penetration point position of each satellite is calculated using the altitude angle and azimuth angle of each satellite.

[0018] In one embodiment, the original observation quantity further includes: dual-frequency carrier phase;

[0019] Based on the above original observations, the vertical total electron content of the ionosphere of each satellite is obtained by the carrier phase smoothed pseudorange method, which includes:

[0020] Based on the dual-frequency carrier phase and the original pseudorange observations, geometry-free combined carrier phase observations and geometry-free combined pseudorange observations are constructed, and the vertical total electron content of the ionosphere of each satellite is obtained by the carrier phase smoothed pseudorange method.

[0021] In one embodiment, screening the satellites to obtain a number of adjacent satellites includes:

[0022] Based on the position of the ionospheric puncture point, it is determined whether each satellite is close to the puncture point. If so, the satellite close to the puncture point is regarded as a nearby satellite, wherein the number of the nearby satellites is greater than or equal to 1.

[0023] In one embodiment, establishing the ionospheric piercing point proximity mathematical model and the stochastic model based on the ionospheric piercing point positions and the ionospheric vertical total electron content corresponding to the plurality of nearby satellites includes:

[0024] The mathematical model of the ionospheric puncture point is established as follows:

[0025] ι n×1 =H n×m α m×1 +ε

[0026] Taking into account the temporal and spatial correlation characteristics of the modeling error, the random model that best matches the mathematical model near the ionospheric puncture point is constructed as follows:

[0027] D[ε]=Q ι

[0028] Among them, ι n×1 represents the vertical total electron content of the ionosphere corresponding to the above-mentioned several nearby satellites; α m×1 represents the m parameters of the mathematical model of the ionospheric puncture point; H n×m represents the corresponding design matrix; ε is the modeling error; Q ι represents the corresponding covariance.

[0029] In one embodiment, the construction of the high-sea precise point positioning model with additional ionospheric delay constraints of the adjacent satellite group based on the ionospheric puncture point proximity mathematical model and the random model includes:

[0030] Based on the above-mentioned mathematical model of the ionospheric puncture point proximity and the above-mentioned random model, a model is constructed to estimate the residual amount;

[0031] The above-mentioned high-sea precise point positioning model is obtained by combining the above-mentioned pseudorange original observations and the above-mentioned dual-frequency carrier phase and performing a deformation operation on the above-mentioned model estimation residual.

[0032] A second aspect of the present application provides a precise point positioning device based on ionospheric puncture point proximity constraints, comprising:

[0033] The first calculation module is used to calculate the position coordinates of each satellite and the approximate position coordinates of the receiver through the satellite ephemeris and the original observation value;

[0034] a second calculation module, configured to calculate the ionospheric penetration point position of each satellite based on the position coordinates of each satellite and the approximate position coordinates of the receiver;

[0035] The third calculation module is used to obtain the vertical total electron content of the ionosphere of each satellite through the carrier phase smoothed pseudorange method based on the above original observations;

[0036] a model building module for screening the satellites to obtain a number of nearby satellites, and then establishing a mathematical model and a stochastic model of the ionospheric piercing point proximity based on the ionospheric piercing point positions and the ionospheric vertical total electron content corresponding to the plurality of nearby satellites, wherein the nearby satellites are satellites that are close to the ionospheric piercing point;

[0037] The precise point positioning module is used to construct a high-seas precise point positioning model with additional ionospheric delay constraints of the adjacent satellite group based on the above-mentioned ionospheric puncture point proximity mathematical model and the above-mentioned random model, and to achieve precise point positioning of the receiver through the above-mentioned high-seas precise point positioning model.

[0038] A third aspect of the present application provides a precise point positioning device based on ionospheric puncture point proximity constraints, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the first aspect or any one of the embodiments of the first aspect when executing the computer program.

[0039] According to a fourth aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the steps of the first aspect or any embodiment of the first aspect are implemented.

[0040] As can be seen from the above, the present application provides a precise single-point positioning method and device based on the proximity constraint of the ionospheric puncture point, which solves the satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content through satellite ephemeris and original observations; then, the adjacent satellites are screened out, and the satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content corresponding to the adjacent satellites are used to establish the ionospheric puncture point proximity function model and the random model; finally, a precise single-point positioning model for the far sea based on the proximity constraint of the ionospheric puncture point is constructed. The precise single-point positioning method and device provided by the present application not only ensure the high-precision positioning performance of PPP in the far sea area, but also shorten the long initialization time of PPP, break through the PPP convergence limit, and realize the rapid convergence of PPP in the far sea area. It is suitable for high-precision positioning in the far sea area, improves the operating efficiency of far sea application fields such as drilling platforms, channel measurement, pipeline laying, unmanned shipping, etc., provides efficient high-precision positioning services in the far sea, and is conducive to promoting the development of the smart ocean economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0042] Figure 1 A flowchart of a precise point positioning method provided in an embodiment of the present application;

[0043] Figure 2 A flowchart of a precise point positioning method provided in an embodiment of the present application;

[0044] Figure 3 A schematic structural diagram of a precision single-point positioning device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] In the following description, specific details such as specific system structures and technologies are provided for illustration rather than limitation to facilitate a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obstructing the description of the present application with unnecessary details.

[0046] It will be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0047] It should also be understood that the terms used in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0048] The following is a clear and complete description of the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0049] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0050] Example 1

[0051] The embodiment of the present application provides a precise point positioning method based on ionospheric puncture point proximity constraints, such as Figure 1 and 2 As shown, the precise point positioning method includes:

[0052] Step 11: Calculate the position coordinates of each satellite and the approximate position coordinates of the receiver using the satellite ephemeris and the original observations;

[0053] Among them, the approximate position coordinates of the receiver are also called the approximate position coordinates of the user receiver. First, the approximate position coordinates of the user receiver are obtained, and then the precise single-point positioning method provided in the embodiment of the present application is used to solve it to obtain a high-precision user receiver position.

[0054] Optionally, the above-mentioned original observations include pseudorange original observations;

[0055] The calculation of the satellite position coordinates and the receiver approximate position coordinates using the satellite ephemeris and the original observations includes:

[0056] The satellite position coordinates r are calculated by the above pseudo-range original observations and the above satellite ephemeriss =(x s ,y s ,z s ), s=1, 2, ... n, where r s represents the position of satellite numbered s, x s ,y s , z s They represent the different axis coordinates of satellite s in the Earth-centered Earth-fixed rectangular coordinate system.

[0057] The single point positioning solution is performed by using the above pseudo-range original observations to obtain the approximate position coordinates of the receiver. Specifically, the approximate position coordinates of the receiver are obtained. r =(x r ,y r ,z r ), where r r represents the approximate position of the receiver numbered r, x r ,y r , z r Represent the different coordinate axes of the receiver r in the Earth-centered Earth-fixed rectangular coordinate system; then, the coordinates of the Earth-centered Earth-fixed rectangular coordinate system (x r ,y r ,z r ) is converted into the geodetic coordinate system coordinate (φ r ,λ r ,h r ), where φ r ,λ r , h r represent the longitude, latitude and altitude of the location of the receiver r respectively.

[0058] Step 12: Calculating the ionospheric penetration point position of each satellite based on the above-mentioned satellite position coordinates and the above-mentioned receiver approximate position coordinates;

[0059] Optionally, the altitude angle and azimuth angle of each satellite are calculated based on the above-mentioned satellite position coordinates and the above-mentioned receiver approximate position coordinates; then the ionospheric puncture point position of each satellite is calculated using the altitude angle and azimuth angle of each satellite.

[0060] Specifically, taking satellite s as an example, the process of calculating the elevation angle and azimuth angle of satellite s is as follows:

[0061] The line of sight vector between the receiver and the satellite in the Earth-centered Earth-fixed rectangular coordinate system for:

[0062]

[0063] The approximate position coordinates of the user receiver r r Establish the station center coordinate system for the origin of the station center coordinate system, and the line of sight vector between the receiver and the satellite Earth-centered Earth-fixed rectangular coordinate system Can be converted into station center coordinate system vector The satellite s azimuth is calculated by the following formula: and altitude angle

[0064]

[0065] Among them, E r Represents the transformation matrix from the Earth-centered Earth-fixed coordinate system to the station-centered coordinate system.

[0066] Get the elevation angle of each satellite and azimuth Then, calculate the position of the ionospheric puncture point of satellite s The specific solution process is as follows:

[0067] The zenith angle z′ of satellite s at the receiver is

[0068]

[0069] The zenith angle z′ of satellite s at the puncture point is

[0070]

[0071] Where H represents the ionosphere height, which is generally 450km;

[0072] The latitude φ of satellite s at the puncture point IPP for

[0073]

[0074] Where, α = zz′;

[0075] When φ r >70° and When, or when φ r <70° and When , the longitude λ of satellite s at the puncture point IPP for

[0076]

[0077] Otherwise, the longitude λ of satellite s at the puncture point IPP for

[0078]

[0079] Step 13: Based on the above raw observations, the vertical total electron content of the ionosphere of each satellite is obtained by the carrier phase smoothed pseudorange method;

[0080] Optionally, the above-mentioned original observation quantity further includes: dual-frequency carrier phase;

[0081] Based on the above original observations, the vertical total electron content of the ionosphere of each satellite is obtained by the carrier phase smoothed pseudorange method, which includes:

[0082] Based on the dual-frequency carrier phase and the original pseudorange observations, geometry-free combined carrier phase observations and geometry-free combined pseudorange observations are constructed, and the vertical total electron content of the ionosphere of each satellite is obtained by the carrier phase smoothed pseudorange method.

[0083] Specifically, the k-epoch geometry-free combined carrier phase observations are constructed using the dual-frequency carrier phase and pseudorange raw observations. and geometry-free combined pseudorange observations The carrier phase smoothed pseudorange method is used to extract the vertical total electron content of the ionosphere of each satellite. The specific calculation process is as follows

[0084]

[0085] in, Represents the average value of m smoothed epochs, R E The radius of the earth is 6371 km, and the correlation coefficient is 0.9782. represents the geometry-free ionospheric delay factor associated with the satellite s frequency, and d r,GF They represent the receiver differential code bias (DCB) and satellite differential code bias (DCB), Represents the ionospheric delay error noise.

[0086] Step 14: Screening the aforementioned satellites to obtain a number of nearby satellites, and then establishing an ionospheric piercing point proximity mathematical model and a stochastic model based on the ionospheric piercing point locations and ionospheric vertical total electron contents corresponding to the aforementioned nearby satellites, wherein the aforementioned nearby satellites are satellites that are close to the ionospheric piercing point;

[0087] Optionally, the screening of the satellites to obtain a number of adjacent satellites includes:

[0088] Based on the aforementioned ionospheric puncture point location, each satellite is determined to be proximal to the puncture point. If so, the satellite proximal to the puncture point is considered a proximal satellite. Otherwise, the satellite (not proximal to the puncture point) is considered a non-proximal satellite and is not included in the subsequent mathematical model for determining the proximal ionospheric puncture point. The number of proximal satellites is greater than or equal to 1. When the number of proximal satellites, n, is greater than 1, the number of proximal satellites is also referred to as a proximal satellite set consisting of n satellites.

[0089] Optionally, establishing the ionospheric piercing point proximity mathematical model and the stochastic model based on the ionospheric piercing point positions and the ionospheric vertical total electron content corresponding to the plurality of nearby satellites includes:

[0090] According to the vertical total electron content of the ionosphere of n satellites The mathematical model of the ionospheric puncture point is established as follows:

[0091] ι n×1 =H n×m α m×1 +ε

[0092] Taking into account the temporal and spatial correlation characteristics of the modeling error, the random model that best matches the mathematical model near the ionospheric puncture point is constructed as follows:

[0093] D[ε]=Q ι

[0094] Among them, ι n×1 represents the vertical total electron content of the ionosphere corresponding to n nearby satellites; α m×1 represents the m parameters of the mathematical model of the ionospheric puncture point; H n×m represents the corresponding design matrix, which is related to factors such as satellite altitude angle, satellite azimuth angle and spatial geographical location; ε is the modeling error, which is related to factors such as the choice of modeling method, fitting order, satellite proximity, and ionospheric activity; Q ι represents the corresponding covariance.

[0095] Step 15: Based on the above-mentioned ionospheric puncture point proximity mathematical model and the above-mentioned random model, a high-seas precise point positioning model with additional ionospheric delay constraints of the adjacent satellite group is constructed, and precise point positioning of the receiver is achieved through the above-mentioned high-seas precise point positioning model.

[0096] Optionally, the above-mentioned construction of a high-sea precise point positioning model with additional ionospheric delay constraints of a nearby satellite group based on the above-mentioned ionospheric puncture point proximity mathematical model and the above-mentioned random model includes:

[0097] Based on the above-mentioned mathematical model of the ionospheric puncture point proximity and the above-mentioned random model, a model is constructed to estimate the residual amount;

[0098] The above-mentioned high-sea precise point positioning model is obtained by combining the above-mentioned pseudorange original observations and the above-mentioned dual-frequency carrier phase and performing a deformation operation on the above-mentioned model estimation residual.

[0099] Specifically, for PPP users, without changing the original non-combined PPP model (traditional PPP model) estimation parameter architecture, the model estimation residual can be used to construct a virtual observation strategy, and the virtual observation strategy can be combined with the actual original observation data to construct a high-sea precise point positioning model with ionospheric delay constraints of the adjacent satellite cluster. The model estimation residual is:

[0100]

[0101] Among them, E and D represent expectation and variance operations respectively; It represents the estimated residual of the mathematical model near the ionospheric puncture point of satellite i; The variance of the vertical total electron content observation of the ionosphere corresponding to satellite i, where I represents the identity matrix.

[0102] Combining the above pseudorange original observations and the above dual-frequency carrier phase to deform the above model estimation residuals and obtain the above high seas precise single point positioning model is:

[0103]

[0104]

[0105] Where p={[p1,p2,…,p i ,…,p n ] T},φ={[φ1,φ1,…,φ i ,…,φ n ] T} respectively represent the frequency pseudorange and carrier phase observation vectors of satellite i and j; n represents the total number of available adjacent satellites; e n Indicates 1 n ×1 column vector; A is the design matrix of the user receiver coordinate vector x; H τ represents the Neill model mapping coefficient matrix corresponding to the vertical tropospheric component τ modified by the Saastamoinen tropospheric model; μ={[μ1,μ1,…,μ i ,…,μ n ] T},μ i represents the ionospheric proportional coefficient of satellite i, ι represents the vertical ionospheric component of the corresponding satellite i based on f1; H ι represents the tilt mapping coefficient corresponding to ι; Λ=diag{[λ1,λ1,…,λ n ]}, indicating the corresponding phase wavelength of n adjacent satellite carriers; N={[N1,N2,…,N n ] T} represents the ambiguity of n nearby satellites; The variance of the pseudorange, carrier phase, and ionospheric vertical total electron content observations corresponding to satellite i; Expressed as the elevation angle weighting coefficient, this offshore precise point positioning model can be used to calculate the high-precision position of the user receiver, achieving precise point positioning of the user receiver.

[0106] As can be seen from the above, the embodiment of the present application provides a precise single-point positioning method based on the proximity constraint of the ionospheric puncture point, which solves the satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content through the satellite ephemeris and the original observation quantity; then the adjacent satellites are screened out, and the satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content corresponding to the adjacent satellites are used to establish the ionospheric puncture point proximity function model and the random model; finally, a precise single-point positioning model for the far sea based on the proximity constraint of the ionospheric puncture point is constructed. The precise single-point positioning method provided by the embodiment of the present application not only ensures the high-precision positioning performance of PPP in the far sea area, but also shortens the long initialization time of PPP, breaks through the PPP convergence limit, and realizes the rapid convergence of PPP in the far sea area. It is suitable for high-precision positioning in the far sea area, improves the operational efficiency of far sea application fields such as drilling platforms, channel measurement, pipeline laying, unmanned shipping, etc., provides efficient high-precision positioning services in the far sea, and is conducive to promoting the development of the smart ocean economy.

[0107] Example 2

[0108] The embodiment of the present application provides a precise point positioning device based on ionospheric puncture point proximity constraint. The structure of the precise point positioning device is as follows: Figure 3 As shown, it includes: a first calculation module 21, a second calculation module 22, a third calculation module 23, a model building module 24 and a precise point positioning module 25;

[0109] The first calculation module 21 is used to calculate the position coordinates of each satellite and the approximate position coordinates of the receiver through the satellite ephemeris and the original observation value;

[0110] The second calculation module 22 is used to calculate the ionospheric penetration point position of each satellite based on the above-mentioned satellite position coordinates and the above-mentioned receiver approximate position coordinates;

[0111] The third calculation module 23 is used to obtain the vertical total electron content of the ionosphere of each satellite through the carrier phase smoothing pseudorange method based on the above original observations;

[0112] The model building module 24 is used to screen the satellites to obtain a number of adjacent satellites, and then establish an ionospheric puncture point proximity mathematical model and a stochastic model based on the ionospheric puncture point positions and ionospheric vertical total electron contents corresponding to the plurality of adjacent satellites, wherein the adjacent satellites are satellites adjacent to the ionospheric puncture point;

[0113] The precise point positioning module 25 is used to construct a high-seas precise point positioning model with additional ionospheric delay constraints of the adjacent satellite group based on the above-mentioned ionospheric puncture point proximity mathematical model and the above-mentioned random model, and realize precise point positioning of the receiver through the above-mentioned high-seas precise point positioning model.

[0114] As can be seen from the above, the embodiment of the present application provides a precise single-point positioning device based on the proximity constraint of the ionospheric puncture point, which can be used for high-precision positioning in the far sea area. The satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content are solved by satellite ephemeris and original observations; then, the adjacent satellites are screened out, and the satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content corresponding to the adjacent satellites are used to establish the ionospheric puncture point proximity function model and the random model; finally, a precise single-point positioning model for the far sea based on the proximity constraint of the ionospheric puncture point is constructed. The precise single-point positioning device provided by the embodiment of the present application not only ensures the high-precision positioning performance of PPP in the far sea area, but also shortens the long initialization time of PPP, breaks through the PPP convergence limit, realizes the rapid convergence of PPP in the far sea area, improves the operational efficiency of far sea application fields such as drilling platforms, channel measurement, pipeline laying, unmanned shipping, etc., provides efficient far sea high-precision positioning services, and is conducive to promoting the development of the smart ocean economy.

[0115] Example 3

[0116] An embodiment of the present application provides a precise point positioning device based on ionospheric puncture point proximity constraints. The device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. The memory is used to store software programs and modules, and the processor executes various functional applications and data processing by executing the software programs and modules stored in the memory. The memory and processor are connected via a bus. Specifically, the processor implements any step of the above-described first embodiment when executing the computer program stored in the memory.

[0117] It should be understood that in the embodiments of the present application, the processor referred to may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0118] The memory may include a read-only memory, a flash memory, and a random access memory, and provides instructions and data to the processor. A portion or all of the memory may also include a non-volatile random access memory.

[0119] As can be seen from the above, the precise single-point positioning device based on the proximity constraint of the ionospheric puncture point provided in the embodiment of the present application can be used for high-precision positioning in the offshore area. The satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content are solved by satellite ephemeris and original observations; then, adjacent satellites are screened out, and the satellite ionospheric puncture point position and the satellite vertical ionosphere total electron content corresponding to the adjacent satellites are used to establish an ionospheric puncture point proximity function model and a random model; finally, a precise single-point positioning model for the offshore area based on the proximity constraint of the ionospheric puncture point is constructed. The precise single-point positioning device provided in the embodiment of the present application not only ensures the high-precision positioning performance of PPP in the offshore area, but also shortens the long initialization time of PPP, breaks through the PPP convergence limit, and realizes rapid convergence of PPP in the offshore area, thereby improving the operational efficiency of offshore application fields such as drilling platforms, channel measurement, pipeline laying, and unmanned shipping, and provides efficient offshore high-precision positioning services, which is conducive to promoting the development of the smart ocean economy.

[0120] It should be understood that if the above-mentioned integrated modules / units are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The above-mentioned computer program can be stored in a computer-readable storage medium, and the computer program, when executed by the processor, can implement the steps of the above-mentioned various method embodiments. Among them, the above-mentioned computer program includes computer program code, and the above-mentioned computer program code can be in source code form, object code form, executable file or some intermediate form. The above-mentioned computer-readable medium may include: any entity or device capable of carrying the above-mentioned computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the above-mentioned computer-readable storage medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction.

[0121] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

[0122] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the above-mentioned device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0123] It should be noted that the methods and detailed examples provided in the above embodiments can be combined with the devices and equipment provided in the embodiments, and references can be made to each other, and no further details will be given.

[0124] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0125] In the embodiments provided herein, it should be understood that the disclosed apparatus / terminal equipment and methods may be implemented in other ways. For example, the apparatus / device embodiments described above are merely illustrative. For example, the division of the modules or units described above is merely a logical functional division. In actual implementation, other division methods may be used, such as combining or integrating multiple units or components into another system, or ignoring or not implementing certain features.

[0126] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A precise point positioning method based on ionospheric puncture point proximity constraint, characterized in that: include: Calculate the position coordinates of each satellite and the approximate position coordinates of the receiver through satellite ephemeris and original observations; Calculating the ionospheric penetration point position of each satellite based on the position coordinates of each satellite and the approximate position coordinates of the receiver; Based on the original observations, the vertical total electron content of the ionosphere of each satellite is obtained by using a carrier phase smoothed pseudorange method; Screening the satellites to obtain a number of adjacent satellites, and then establishing an ionospheric piercing point proximity mathematical model and a stochastic model based on ionospheric piercing point positions and ionospheric vertical total electron contents corresponding to the plurality of adjacent satellites, wherein the adjacent satellites are satellites adjacent to the ionospheric piercing point; Based on the ionospheric puncture point proximity mathematical model and the random model, a high-seas precise point positioning model with additional ionospheric delay constraints of a nearby satellite group is constructed, and precise point positioning of the receiver is achieved through the high-seas precise point positioning model.

2. The precise point positioning method according to claim 1, wherein: The original observations include pseudorange original observations; Then the calculation of the position coordinates of each satellite and the approximate position coordinates of the receiver using the satellite ephemeris and the original observation quantity includes: Calculating satellite position coordinates using the pseudorange original observations and the satellite ephemeris; The single point positioning solution is performed using the original pseudo-range observations to obtain the approximate position coordinates of the receiver.

3. The precise point positioning method according to claim 2, wherein: The calculating of the ionospheric penetration point position of each satellite based on the position coordinates of each satellite and the approximate position coordinates of the receiver includes: Calculating the altitude and azimuth of each satellite based on the position coordinates of each satellite and the approximate position coordinates of the receiver; The ionospheric penetration point position of each satellite is calculated using the altitude angle and azimuth angle of each satellite.

4. The precise point positioning method according to claim 3, wherein: The original observation quantity also includes: dual-frequency carrier phase; Then, obtaining the vertical total electron content of the ionosphere of each satellite by the carrier phase smoothed pseudorange method based on the original observation amount includes: Based on the dual-frequency carrier phase and the pseudorange original observation, a geometry-free combined carrier phase observation and a geometry-free combined pseudorange observation are constructed, and the vertical total electron content of the ionosphere of each satellite is obtained by a carrier phase smoothed pseudorange method.

5. The precise point positioning method according to claim 4, wherein: The screening of the satellites to obtain a number of adjacent satellites includes: Based on the position of the ionospheric puncture point, it is determined whether each satellite is close to the puncture point. If so, the satellite close to the puncture point is used as a nearby satellite, wherein the number of the nearby satellites is greater than or equal to 1.

6. The precise point positioning method according to claim 5, wherein: The establishing of the ionospheric piercing point proximity mathematical model and the stochastic model based on the ionospheric piercing point positions corresponding to the plurality of adjacent satellites and the ionospheric vertical total electron content comprises: The mathematical model of the ionospheric puncture point is established as Taking into account the temporal and spatial correlation characteristics of the modeling error, the random model that best matches the mathematical model near the ionospheric puncture point is constructed as follows: in, l n×1 represents the vertical total electron content of the ionosphere corresponding to the several nearby satellites; α m×1 represents the m parameters of the mathematical model of the proximity of the ionospheric puncture point; H n×m Represents the corresponding design matrix, which is related to the satellite altitude angle, satellite azimuth angle and spatial geographical location; ε is the modeling error; Q l represents the corresponding covariance.

7. The precise point positioning method according to claim 6, wherein: The method of constructing a high-sea precise point positioning model with additional ionospheric delay constraints of a nearby satellite group based on the ionospheric puncture point proximity mathematical model and the random model includes: Constructing a model based on the ionospheric puncture point proximity mathematical model and the random model to estimate the residual amount; The high seas precise point positioning model is obtained by combining the pseudorange original observations and the dual-frequency carrier phase and performing a deformation operation on the model estimation residual.

8. A precise point positioning device based on ionospheric puncture point proximity constraint, characterized in that: include: The first calculation module is used to calculate the position coordinates of each satellite and the approximate position coordinates of the receiver through the satellite ephemeris and the original observation value; a second calculation module, configured to calculate the ionospheric penetration point position of each satellite based on the position coordinates of each satellite and the approximate position coordinates of the receiver; A third calculation module is used to obtain the vertical total electron content of the ionosphere of each satellite by a carrier phase smoothed pseudorange method based on the original observation amount; a model building module, configured to screen the satellites to obtain a plurality of adjacent satellites, and then establish an ionospheric piercing point proximity mathematical model and a stochastic model based on the ionospheric piercing point positions and the ionospheric vertical total electron content corresponding to the plurality of adjacent satellites, wherein the adjacent satellites are satellites adjacent to the ionospheric piercing point; The precise point positioning module is used to construct a high-seas precise point positioning model with additional ionospheric delay constraints of a nearby satellite group based on the ionospheric puncture point proximity mathematical model and the random model, and to achieve precise point positioning of the receiver through the high-seas precise point positioning model.

9. A precise point positioning device based on ionospheric penetration point proximity constraint, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method according to any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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