Electronic density acquisition method based on IRI model and related system

Abstract

The embodiment of the invention discloses an electron density obtaining method based on an IRI model and a related system, the accurate total electron content of a second ionized layer of the IRI model is obtained according to the time and position of the total electron content of a first ionized layer in a GNSS system and the IRI model, and the accurate total electron content of the second ionized layer is obtained by introducing two parameters of time and space. Therefore, the total electron content of the second ionized layer can reflect the local change characteristic of the ionized layer; obtaining an ionized layer index according to the total electron content of the first ionized layer and the total electron content of the second ionized layer; and the ionosphere index is interpolated into the IRI model to obtain the electron density of the ionosphere, so that the accuracy of the obtained electron density is improved.

Description

[Technical field]

[0001] The present invention relates to the technical field of GNSS precision data processing, and in particular to an electron density acquisition method based on an IRI model and a related system. [Background technology]

[0002] As an important part of the Sun-Earth space, the ionosphere can cause different degrees of influence on the radio signals passing through it, such as refraction, reflection, scattering and absorption, thus affecting the performance of radio systems such as satellite navigation, aerospace, and communication. In order to study the structure of the ionosphere and its impact on radio signals, people have long used sounding rockets, ionospheric sounders, radars and other means to detect the dynamic changes of the ionosphere. In recent decades, with the establishment and operation of the new generation of global navigation satellite system GNSS (Global Navigation Satellite System), GNSS has also become an important means of monitoring the ionosphere. The increasingly improved multi-frequency and multi-mode GNSS monitoring stations provide rich observation data for ionospheric research. Using GNSS to calculate ionospheric TEC (total electron content) is currently the most widely used and more accurate ionospheric monitoring method. However, since GNSS stations are mainly distributed in land areas, it is unrealistic to use GNSS to monitor ionospheric changes everywhere on the earth. The International Reference Ionosphere (IRI) is an empirical model that can describe the characteristic parameters of the ionosphere at any time and region.

[0003] Since the IRI model is based on a large amount of existing data, its accuracy in a specific region and time strongly depends on the basic database. However, the relevant data of the ionosphere in China were not used when the IRI model was established, so the accuracy of the IRI model in China is not high. Using external high-precision TEC data to adjust the driving parameter IG12 (global ionospheric index) of the IRI model to improve the accuracy of its output characteristic parameters such as the total electron content (TEC) of the ionosphere, electron density and its corresponding height is an important model improvement method. At present, many domestic and foreign studies on the improvement of the IRI model mainly focus on using global or regional GNSS-TEC to perform large-scale fitting and update the IG12 index. This improvement study ignores the local variation characteristics of the ionosphere, resulting in a large deviation in the obtained electron density. [Summary of the invention]

[0004] In view of this, the present invention provides an electron density acquisition method based on the IRI model and a related system.

[0005] The specific technical solution of the first embodiment of the present invention is: a method for obtaining electron density based on the IRI model, the method comprising: obtaining the second ionosphere total electron content of the IRI model according to the time, position and IRI model of the first ionosphere total electron content in the GNSS system; obtaining an ionosphere index according to the first ionosphere total electron content and the second ionosphere total electron content; and interpolating the ionosphere index into the IRI model to obtain the electron density of the ionosphere.

[0006] Preferably, the method further comprises: performing non-difference non-combined precise single-point positioning on the GNSS observation data to obtain the first ionospheric total electron content.

[0007] Preferably, the obtaining of the ionospheric index according to the first ionospheric total electron content and the second ionospheric total electron content comprises: obtaining an electron content difference by subtracting the first ionospheric total electron content from the second ionospheric total electron content; obtaining an ionospheric index update coefficient according to the electron content difference and a preset special library threshold; and obtaining the ionospheric index according to the second ionospheric total electron content and the ionospheric index update coefficient.

[0008] Preferably, the ionospheric index is obtained using the following formula:

[0009] IRI-TEC=IRI(IG 12 ±ξ)

[0010] Wherein, IRI-TEC is the total electron content of the second ionosphere, IRI is the IRI model, IG 12 is the ionospheric index, and ξ is the ionospheric index update coefficient.

[0011] Preferably, after obtaining the ionospheric index, it also includes: optimizing the ionospheric index using a weighted spatial gridding method to obtain a driving index corresponding to different grid points; obtaining an ionospheric evaluation index based on the driving index and the ionospheric index; then interpolating the ionospheric index into the IRI model to obtain the electron density of the ionosphere includes: interpolating the ionospheric evaluation index into the IRI model to obtain the electron density of the ionosphere.

[0012] Preferably, the grid value of the ionospheric index is obtained using the following formula:

[0013]

[0014] Among them, IG(λ,β) is the driving index corresponding to the grid point (λ,β), IG i is the ionospheric index, d i is the spherical distance from the GNSS ground station to the grid node, and k is the power value of the inverse distance weighting.

[0015] Preferably, the ionospheric evaluation index is obtained using the following formula:

[0016]

[0017] Among them, IG(λ0+pΔλ,β0+qΔβ) is the ionospheric evaluation index of the position to be inserted (λ0, β0), IG 00 IG 01 IG 10 IG 11 is the ionospheric evaluation index of the four grid points closest to the location to be inserted, and p is the ionospheric evaluation index of the four grid points closest to the location to be inserted and IG 00 The distance ratio in the longitude direction, q is the distance between the position to be interpolated and IG 00 The distance ratio in the latitude direction, Δλ is the longitude interval of the grid, and Δβ is the latitude interval of the grid.

[0018] The specific technical solution of the second embodiment of the present invention is: an electron density acquisition system based on the IRI model, the system comprising: an ionospheric electron total content acquisition module, an ionospheric index acquisition module and an interpolation module; the ionospheric electron total content acquisition module is used to obtain the second ionospheric electron total content of the IRI model according to the time, position and IRI model of the first ionospheric electron total content in the GNSS system; the ionospheric index acquisition module is used to obtain the ionospheric index according to the first ionospheric electron total content and the second ionospheric electron total content; the interpolation module is used to interpolate the ionospheric index into the IRI model to obtain the electron density of the ionosphere.

[0019] The specific technical solution of the third embodiment of the present invention is: an electron density acquisition device based on the IRI model, comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method described in any one of the first embodiments of the present application.

[0020] The specific technical solution of the fourth embodiment of the present invention is: a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to perform the steps of the method described in any one of the first embodiments of the present application.

[0021] Implementing the embodiments of the present invention will have the following beneficial effects:

[0022] The present invention obtains the accurate second ionosphere total electron content of the IRI model according to the time, position and IRI model of the first ionosphere total electron content in the GNSS system, and introduces two parameters, time and space, so that the second ionosphere total electron content can reflect the local change characteristics of the ionosphere; the ionosphere index is obtained according to the first ionosphere total electron content and the second ionosphere total electron content; and the ionosphere index is interpolated into the IRI model to obtain the electron density of the ionosphere, thereby improving the accuracy of the obtained electron density.

Brief Description of the Drawings

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 paying creative work.

[0024] Figure 1 A flowchart of the steps of the electron density acquisition method based on the IRI model;

[0025] Figure 2 Flow chart of the steps to obtain IRI-TEC values;

[0026] Figure 3 Flow chart of the steps for obtaining ionospheric indices;

[0027] Figure 4 Flow chart of the steps for optimizing the ionospheric index;

[0028] Figure 5 It is a schematic diagram of the structure of the electron density acquisition system based on the IRI model;

[0029] Figure 6 A diagram of the internal structure of a computer device;

[0030] Among them, 401 is an ionospheric electron total content acquisition module; 402 is an ionospheric index acquisition module; 403 is an interpolation module. [Specific implementation method]

[0031] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] The terms "first", "second", etc. in the specification, claims and drawings of this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or modules is not limited to the listed steps or modules, but optionally includes steps or modules that are not listed, or optionally includes other steps or modules that are inherent to these processes, methods, products or devices.

[0033] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0034] GNSS-TEC data mainly includes the total electron content (TEC) information of the ionosphere from the Global Positioning System (GPS), which is obtained by inverting the observation data of the Global Navigation Satellite System (GNSS). GNSS-TEC data is very important for studying the structure and dynamic changes of the ionosphere because it provides a direct measurement of the number of free electrons in the ionosphere.

[0035] The acquisition and analysis of GNSS-TEC data involves multiple steps and techniques. First, the GNSS receiver receives signals from multiple satellites and measures parameters such as signal propagation time. After processing, these data can be inverted to obtain the electron content in the ionosphere, i.e. TEC. The measurement value of TEC is in TECU (Total Electron Content Units), which represents the total number of electrons per unit cross-sectional area in the ionosphere.

[0036] When analyzing GNSS-TEC data, researchers may use different techniques to improve the accuracy and reliability of the data. For example, by fusing satellite-based inversion TEC with ground-based GNSS TEC data, the limitations of each method can be compensated and the global coverage and accuracy of ionospheric monitoring can be improved. In addition, the accuracy of GNSS-TEC data can be further verified and calibrated using high-precision measurement technologies such as incoherent scatter radar (ISR).

[0037] See also Figure 1 , is a flowchart of a method for obtaining electron density based on an IRI model in the first embodiment of the present application, thereby improving the accuracy of the obtained electron density, the method comprising:

[0038] Step 101, obtaining a second ionospheric total electron content IRI-TEC of an IRI model according to the time, position and IRI model of a first ionospheric total electron content GNSS-TEC in a GNSS system;

[0039] Step 102: Obtain an ionospheric index IG according to the first ionospheric total electron content GNSS-TEC and the second ionospheric total electron content IRI-TEC. 12 ;

[0040] Step 103: interpolate the ionospheric index into the IRI model to obtain the electron density of the ionosphere.

[0041] Specifically, the second ionospheric total electron content IRI-TEC value is calculated based on the time and position of the first ionospheric total electron content GNSS-TEC and the coefficients and index indexes in the IRI model, where CCIR, URSI, and IGRF are coefficient files contained in the IRI model, and IG_RZ.DAT and APF107.DAT are index indexes in the IRI model, which can be used to index the solar activity index, ionospheric index, and geomagnetic index. Input the necessary parameters (time and position), and optionally input geomagnetism, solar activity index, ionospheric index, and various characteristic parameters. These input parameters are calculated together with the coefficients and index indexes in the model to obtain the characteristic parameters of each layer, and finally the ionization density profile and IRI-TEC information at a specific position and time are obtained; please refer to the flowchart of the steps to obtain the IRI-TEC value. Figure 2 ; The ionospheric index IG is obtained based on the first ionospheric total electron content GNSS-TEC and the second ionospheric total electron content IRI-TEC 12 ; The ionospheric index IG 12 The electron density of the ionosphere is obtained by interpolation into the IRI model.

[0042] The method in this embodiment obtains the accurate second ionosphere total electron content of the IRI model according to the time, position and IRI model of the first ionosphere total electron content in the GNSS system, and introduces two parameters, time and space, so that the second ionosphere total electron content can reflect the local change characteristics of the ionosphere; obtains the ionosphere index according to the first ionosphere total electron content and the second ionosphere total electron content; and interpolates the ionosphere index into the IRI model to obtain the electron density of the ionosphere, thereby improving the accuracy of the obtained electron density.

[0043] In a specific embodiment, the method further includes: performing non-differenced non-combined precise point positioning on the GNSS observation data to obtain the first ionospheric total electron content. Specifically, based on the GNSS non-differenced non-combined precise point positioning (PPP) method, a high-precision slant total electron content (Slant Total Electron Content, STEC) is extracted; since STEC is linearly related to the satellite and receiver DCB, the STEC directly extracted by PPP contains the satellite and receiver DCB information, and then a quadratic polynomial function can be used to separate and obtain a clean GNSS-TEC value.

[0044] In the specific embodiments, see Figure 3 , in step 102, obtaining an ionospheric index according to the first ionospheric total electron content and the second ionospheric total electron content includes:

[0045] Step 201: Subtract the first ionospheric total electron content GNSS-TEC from the second ionospheric total electron content IRI-TEC to obtain an electron content difference DTEC;

[0046] Step 202, obtaining an ionospheric index update coefficient ξ according to the electron content difference DTEC and a preset special library threshold TECu;

[0047] Step 203: Obtain the ionospheric index IG according to the second ionospheric total electron content IRI-TEC and the ionospheric index update coefficient ξ 12 .

[0048] Specifically, the difference between GNSS-TEC and IRI-TEC (DTEC) is calculated, and the IRI model control parameter IG is adjusted by iterative calculation. 12 The index makes DTEC meet the set threshold (|DTEC|<0.5TECu), where DTEC=GNSS-TEC-IRI-TEC.

[0049] In a specific embodiment, the ionospheric index IG 12 Use the following formula to obtain:

[0050] IRI-TEC=IRI(IG 12 ±ξ)

[0051] Wherein, IRI-TEC is the total electron content of the second ionosphere, IRI is the IRI model, IG 12 is the ionospheric index, and ξ is the ionospheric index update coefficient.

[0052] The ionospheric index update coefficient ξ is obtained using the following formula:

[0053]

[0054] In the specific embodiments, see Figure 4 , after obtaining the ionospheric index, the method further comprises:

[0055] Step 301: Optimize the ionospheric index using a weighted spatial gridding method to obtain driving indices IG (λ, β) corresponding to different grid points;

[0056] Step 302: According to the driving index IG(λ,β) and the ionospheric index IG 12 Obtain the ionospheric evaluation index IG-up;

[0057] Then, interpolating the ionospheric index into the IRI model to obtain the electron density of the ionosphere includes:

[0058] Step 303: interpolate the ionospheric evaluation index IG-up into the IRI model to obtain the electron density of the ionosphere.

[0059] Specifically, the ionospheric index IG is calculated using a 1-hour time interpolation scheme and a 5° longitude × 2.5° latitude distance weighted spatial gridding scheme. 12 Optimize and obtain the driving index IG(λ,β) corresponding to different grid points; according to the driving index IG(λ,β) and the ionospheric index IG 12 The ionospheric evaluation index IG-up is obtained. Among them, the 1-hour time interpolation scheme: iteratively update at 0:00, 1:00, 3:00...24:00 to obtain the hourly IG-up; the longitude 5°×latitude 2.5° distance weighted spatial gridding scheme: use different GNSS ground stations to calculate the IG-up value, and grid the IG-up value with a resolution of 5°×2.5° in longitude and latitude in the range of 20°N-55°N and 70°E-135°E according to the spherical distance weighted inverse strategy, and then interpolate at different grid intervals to obtain the effective IG-up value at a specific location. Among them, the spherical distance range set in the process of gridding the IG-up value by the spherical distance weighted inverse strategy does not exceed 500km.

[0060] In a specific embodiment, the grid value of the ionospheric index is obtained using the following formula:

[0061]

[0062] Where IG(λ,β) is the driving index corresponding to the grid point (λ,β), IGi is the ionospheric index, and d iis the spherical distance from the GNSS ground station to the grid node, and k is the power value of the inverse distance weighting. Generally speaking, 0≤k≤3, the larger the k value, the more prominent the role of the neighboring point. In this application, k=2 is used.

[0063] In a specific embodiment, the ionospheric evaluation index is obtained using the following formula:

[0064]

[0065] Among them, IG(λ0+pΔλ,β0+qΔβ) is the ionospheric evaluation index of the position to be inserted (λ0, β0), IG 00 IG 01 IG 10 IG 11 is the ionospheric evaluation index of the four grid points closest to the location to be inserted, and p is the ionospheric evaluation index of the four grid points closest to the location to be inserted and IG 00 The distance ratio in the longitude direction, q is the distance between the position to be interpolated and IG 00 The distance ratio in the latitude direction, 0≤p<1 and 0≤q<1, Δλ is the longitude interval of the grid, and Δβ is the latitude interval of the grid.

[0066] In the specific embodiments, see Figure 5 , a structural schematic diagram of an electron density acquisition system based on an IRI model is provided for the second embodiment of the present application, the system comprising: an ionospheric electron total content acquisition module 401, an ionospheric index acquisition module 402 and an interpolation module 403; the ionospheric electron total content acquisition module 401 is used to obtain a second ionospheric electron total content of the IRI model according to the time, position and IRI model of the first ionospheric electron total content in the GNSS system; the ionospheric index acquisition module 402 is used to obtain an ionospheric index according to the first ionospheric electron total content and the second ionospheric electron total content; the interpolation module 403 is used to interpolate the ionospheric index into the IRI model to obtain the electron density of the ionosphere.

[0067] The system in this embodiment can obtain the accurate second ionosphere total electron content of the IRI model according to the time, position and IRI model of the first ionosphere total electron content in the GNSS system, and by introducing two parameters, time and space, the second ionosphere total electron content can reflect the local change characteristics of the ionosphere; obtain the ionosphere index according to the first ionosphere total electron content and the second ionosphere total electron content; and interpolate the ionosphere index into the IRI model to obtain the electron density of the ionosphere, thereby improving the accuracy of the obtained electron density.

[0068] Specifically, the system in this embodiment extracts high-precision slant total electron content (Slant Total Electron Content, STEC) based on the GNSS non-difference non-combined precise single point positioning (PPP) method; since STEC is linearly related to the satellite and receiver DCB, the STEC directly extracted by PPP contains the satellite and receiver DCB information, and then the quadratic polynomial function can be used to separate and obtain a clean GNSS-TEC value. The IRI-TEC value is calculated based on the time and position and the coefficients and index indexes inside the IRI model, where CCIR, URSI, and IGRF are coefficient files contained in the IRI model, and IG_RZ.DAT and APF107.DAT are index indexes in the IRI model, which can index the solar activity index, ionospheric index, and geomagnetic index. Input necessary parameters (time and location), and optionally input geomagnetic field, solar activity index, ionospheric index and various characteristic parameters. These input parameters are used together with the coefficients and index indexes inside the model to calculate the characteristic parameters of each layer, and finally obtain the ionization density profile and ionospheric TEC information at a specific location and time. Calculate the difference (DTEC) between GNSS-TEC and IRI-TEC, and iterate to adjust the IRI model control parameter IG 12 After the DTEC index is adjusted and DTEC meets the set threshold (|DTEC|<0.5TECu), the IG-up driving parameter value can be obtained. The IG-up driving parameter reflects the error of the CCIR coefficient describing the ionospheric critical frequency in different time and space to a certain extent, that is, the IG-up value varies greatly with time and space. The 1-hour time interpolation scheme and the 5° longitude × 2.5° latitude distance weighted spatial gridding scheme are used to calculate the IG-up. 12 The index is optimized and interpolated to obtain IG-up, and the IG-up value is finally substituted into IRI-2016 to calculate the electron density. Among them, the 1-hour time interpolation scheme: iteratively update at 0:00, 1:00, 3:00...24:00 to obtain the hourly IG-up; the longitude 5°×latitude 2.5° distance weighted spatial gridding scheme: use different GNSS ground stations to calculate the IG-up value, and grid the IG-up value with a resolution of 5°×2.5° in longitude and latitude within the range of 20°N-55°N and 70°E-135°E according to the spherical distance weighted inverse strategy, and then interpolate at different grid intervals to obtain the effective IG-up value at a specific location. Among them, the spherical distance range set in the process of gridding the IG-up value by the spherical distance weighted inverse strategy does not exceed 500km.

[0069] In a specific embodiment, the third embodiment of the present application provides an electron density acquisition device based on the IRI model, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method described in any one of the first embodiments of the present application. Specifically, the device in this embodiment extracts high-precision slant total electron content (Slant Total Electron Content, STEC) based on the GNSS non-differential non-combined precise single point positioning (Precise Point Positioning, PPP) method; since STEC is linearly related to the satellite and receiver DCB, the STEC directly extracted by PPP contains the satellite and receiver DCB information, and then the quadratic polynomial function can be used to separate and obtain a clean GNSS-TEC value. The IRI-TEC value is calculated based on the time and position and the coefficients and index indexes inside the IRI model, wherein CCIR, URSI, and IGRF are coefficient files contained in the IRI model, and IG_RZ.DAT and APF107.DAT are index indexes in the IRI model, which can index the solar activity index, ionospheric index, and geomagnetic index. Input necessary parameters (time and location), and optionally input geomagnetic field, solar activity index, ionospheric index and various characteristic parameters. These input parameters are used together with the coefficients and index indexes inside the model to calculate the characteristic parameters of each layer, and finally obtain the ionization density profile and ionospheric TEC information at a specific location and time. Calculate the difference (DTEC) between GNSS-TEC and IRI-TEC, and iterate to adjust the IRI model control parameter IG 12 After the DTEC index is adjusted and DTEC meets the set threshold (|DTEC|<0.5TECu), the IG-up driving parameter value can be obtained. The IG-up driving parameter reflects the error of the CCIR coefficient describing the ionospheric critical frequency in different time and space to a certain extent, that is, the IG-up value varies greatly with time and space. The 1-hour time interpolation scheme and the 5° longitude × 2.5° latitude distance weighted spatial gridding scheme are used to calculate the IG-up. 12The index is optimized and interpolated to obtain IG-up, and the IG-up value is finally substituted into IRI-2016 to calculate the electron density. Among them, the 1-hour time interpolation scheme: iteratively update at 0:00, 1:00, 3:00...24:00 to obtain the hourly IG-up; the longitude 5°×latitude 2.5° distance weighted spatial gridding scheme: use different GNSS ground stations to calculate the IG-up value, and grid the IG-up value with a resolution of 5°×2.5° in longitude and latitude within the range of 20°N-55°N and 70°E-135°E according to the spherical distance weighted inverse strategy, and then interpolate at different grid intervals to obtain the effective IG-up value at a specific location. Among them, the spherical distance range set in the process of gridding the IG-up value by the spherical distance weighted inverse strategy does not exceed 500km.

[0070] The device in this embodiment can obtain the accurate second ionosphere total electron content of the IRI model according to the time, position and IRI model of the first ionosphere total electron content in the GNSS system, and by introducing two parameters, time and space, the second ionosphere total electron content can reflect the local change characteristics of the ionosphere; obtain the ionosphere index according to the first ionosphere total electron content and the second ionosphere total electron content; and interpolate the ionosphere index into the IRI model to obtain the electron density of the ionosphere, thereby improving the accuracy of the obtained electron density.

[0071] In a specific embodiment, the fourth embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the processor executes the steps of the method described in any one of the first embodiments of the present application. Specifically, the storage medium in this embodiment extracts high-precision slant total electron content (Slant Total Electron Content, STEC) based on the GNSS non-differential non-combined precise single point positioning (Precise Point Positioning, PPP) method; since STEC is linearly related to the satellite and receiver DCB, the STEC directly extracted by PPP contains satellite and receiver DCB information, and then a quadratic polynomial function can be used to separate and obtain a clean GNSS-TEC value. The IRI-TEC value is calculated based on the time and position and the coefficients and index indexes inside the IRI model, where CCIR, URSI, and IGRF are coefficient files contained in the IRI model, and IG_RZ.DAT and APF107.DAT are index indexes in the IRI model, which can index the solar activity index, ionospheric index, and geomagnetic index. Input necessary parameters (time and location), and optionally input geomagnetic field, solar activity index, ionospheric index and various characteristic parameters. These input parameters are used together with the coefficients and index indexes inside the model to calculate the characteristic parameters of each layer, and finally obtain the ionization density profile and ionospheric TEC information at a specific location and time. Calculate the difference (DTEC) between GNSS-TEC and IRI-TEC, and iterate to adjust the IRI model control parameter IG 12 After the DTEC index is adjusted and DTEC meets the set threshold (|DTEC|<0.5TECu), the IG-up driving parameter value can be obtained. The IG-up driving parameter reflects the error of the CCIR coefficient describing the ionospheric critical frequency in different time and space to a certain extent, that is, the IG-up value varies greatly with time and space. The 1-hour time interpolation scheme and the 5° longitude × 2.5° latitude distance weighted spatial gridding scheme are used to calculate the IG-up. 12The index is optimized and interpolated to obtain IG-up, and the IG-up value is finally substituted into IRI-2016 to calculate the electron density. Among them, the 1-hour time interpolation scheme: iteratively update at 0:00, 1:00, 3:00...24:00 to obtain the hourly IG-up; the longitude 5°×latitude 2.5° distance weighted spatial gridding scheme: use different GNSS ground stations to calculate the IG-up value, and grid the IG-up value with a resolution of 5°×2.5° in longitude and latitude within the range of 20°N-55°N and 70°E-135°E according to the spherical distance weighted inverse strategy, and then interpolate at different grid intervals to obtain the effective IG-up value at a specific location. Among them, the spherical distance range set in the process of gridding the IG-up value by the spherical distance weighted inverse strategy does not exceed 500km. The storage medium in this embodiment can obtain the accurate second ionosphere total electron content of the IRI model according to the time, position and IRI model of the first ionosphere total electron content in the GNSS system, and by introducing two parameters, time and space, the second ionosphere total electron content can reflect the local change characteristics of the ionosphere; obtain the ionosphere index according to the first ionosphere total electron content and the second ionosphere total electron content; and interpolate the ionosphere index into the IRI model to obtain the electron density of the ionosphere, thereby improving the accuracy of the obtained electron density.

[0072] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] Figure 6 The internal structure of a computer device in one embodiment is shown. The computer device can be a terminal or a server. Figure 6 The computer device includes a processor, a memory, a boot link setting module, a jump module, a reservation module, a display module, and a confirmation module connected through a system bus. Among them, the memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the computer device stores an operating system and may also store a computer program. When the computer program is executed by the processor, the processor can implement the method in this embodiment. The internal memory may also store a computer program. When the computer program is executed by the processor, the processor can implement the method in this embodiment. Those skilled in the art can understand that Figure 6 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0074] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

[0075] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for obtaining electron density based on the IRI model, characterized in that: The method comprises: According to the time, position and IRI model of the first ionospheric total electron content in the GNSS system, the second ionospheric total electron content of the IRI model is obtained; Obtaining an ionospheric index according to the first ionospheric total electron content and the second ionospheric total electron content; The ionospheric index is interpolated into the IRI model to obtain the electron density of the ionosphere.

2. The electron density acquisition method based on the IRI model according to claim 1, characterized in that: The method also includes: performing non-difference non-combined precise single-point positioning on the GNSS observation data to obtain the first ionospheric total electron content.

3. The electron density acquisition method based on the IRI model according to claim 1, characterized in that: The obtaining of the ionospheric index according to the first ionospheric total electron content and the second ionospheric total electron content comprises: Subtracting the total electron content of the first ionosphere from the total electron content of the second ionosphere to obtain an electron content difference; Obtaining an ionospheric index update coefficient according to the electron content difference and a preset special library threshold; The ionospheric index is obtained according to the second ionospheric total electron content and the ionospheric index update coefficient.

4. The electron density acquisition method based on the IRI model according to claim 3, characterized in that: The ionospheric index is obtained using the following formula: <h2 style=";text-align:left;direction:ltr">IRI-TEC=IRI(IG<h2 style=";text-align:left;direction:ltr"> 12 <h2 style=";text-align:left;direction:ltr"> ±ξ) Wherein, IRI-TEC is the total electron content of the second ionosphere, IRI is the IRI model, IG 12 is the ionospheric index, and ξ is the ionospheric index update coefficient.

5. The electron density acquisition method based on the IRI model according to claim 1, characterized in that: After obtaining the ionospheric index, the method further includes: The ionospheric index is optimized by using a weighted spatial gridding method to obtain driving indices corresponding to different grid points; Obtaining an ionospheric assessment index according to the driving index and the ionospheric index; Then, interpolating the ionospheric index into the IRI model to obtain the electron density of the ionosphere includes: The ionospheric evaluation index is interpolated into the IRI model to obtain the electron density of the ionosphere.

6. The electron density acquisition method based on the IRI model according to claim 5, characterized in that: The grid value of the ionospheric index is obtained using the following formula: Among them, IG(λ, β) is the driving index corresponding to the grid point (λ, β), IG i is the ionospheric index, d i is the spherical distance from the GNSS ground station to the grid node, and k is the power value of the inverse distance weighting.

7. The electron density acquisition method based on the IRI model according to claim 5, characterized in that: The ionospheric evaluation index is obtained using the following formula: IG(λ0+pΔλ,β0+qΔβ)=(1-p)(1-q)IG 0，0 +p(1-q)IG 1,0 +q(1-p)IG 0，1 +pqIG 1，1 Among them, IG(λ0+pΔλ, β0+qΔβ) is the ionospheric evaluation index of the position to be inserted (λ0, β0), IG 00 IG 01 IG 10 IG 11 is the ionospheric evaluation index of the four grid points closest to the location to be inserted, and p is the ionospheric evaluation index of the four grid points closest to the location to be inserted and IG 00 The distance ratio in the longitude direction, q is the distance between the position to be interpolated and IG 00 The distance ratio in the latitude direction, Δλ is the longitude interval of the grid, and Δβ is the latitude interval of the grid.

8. An electron density acquisition system based on the IRI model, characterized in that: The system comprises: an ionospheric electron total content acquisition module, an ionospheric index acquisition module and an interpolation module; The ionospheric electron total content acquisition module is used to obtain the second ionospheric electron total content of the IRI model according to the time, position and IRI model of the first ionospheric electron total content in the GNSS system; The ionospheric index acquisition module is used to obtain the ionospheric index according to the first ionospheric total electron content and the second ionospheric total electron content; The interpolation module is used to interpolate the ionospheric index into the IRI model to obtain the electron density of the ionosphere.

9. An electron density acquisition device based on an IRI model, comprising a memory and a processor, characterized in that: The memory stores a computer program, and when the computer program is executed by the processor, the processor is caused to perform the steps of the method according to any one of claims 1 to 7.

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

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