Satellite-based enhanced integrated differential GNSS real-time PNT method and equipment

Abstract

The present invention belongs to the field of satellite navigation technology, and specifically relates to a satellite-based ground-based enhanced integrated differential GNSS real-time PNT method and device. The method includes: obtaining configuration files, mobile station data, reference station data, broadcast ephemeris and enhanced service products; selecting the observation value type corresponding to the GNSS real-time PNT according to the configuration files, mobile station data and reference station data; calculating the differential observation value corresponding to the GNSS real-time PNT based on the observation value type corresponding to the GNSS real-time PNT; judging the available status of the enhanced service product, and correcting the GNSS real-time PNT error according to the broadcast ephemeris, the available status of the enhanced service product and the differential observation value corresponding to the GNSS real-time PNT, so as to perform satellite-based ground-based real-time dynamic enhancement of the GNSS real-time PNT. The present invention realizes a GNSS real-time PNT technology with high-precision, real-time and all-round error correction by integrating satellite-based and ground-based augmentation data, and can flexibly select different positioning modes, and has excellent compatibility and flexibility.

Description

Technical Field

[0001] The present invention belongs to the field of satellite navigation technology, and in particular relates to a satellite base-based enhanced integrated differential GNSS real-time PNT method and device. Background Art

[0002] The Global Navigation Satellite System (GNSS) includes GPS, BeiDou (BDS), GLONASS, Galileo, QZSS and NavIC, providing high-precision and highly reliable positioning, navigation and timing (PNT) services for many fields such as intelligent transportation, precision agriculture, and environmental monitoring. In GNSS navigation and positioning, two methods, absolute positioning and relative positioning, are mainly used to solve the position parameters. Absolute positioning is limited to error absorption and correction mode, while relative positioning reduces system errors by differential method. Among them, real-time phase differential positioning (RTK) has much higher positioning accuracy than real-time pseudorange differential positioning (RTD) due to its high observation accuracy. However, in complex scenarios, pseudorange and phase observations are easily affected by satellite errors and atmosphere-related errors. Especially in long-distance observations, the positioning accuracy of traditional GNSS methods is difficult to meet the requirements of centimeter-level or even higher accuracy. In order to improve positioning accuracy, satellite-based augmentation systems (SBAS) and ground-based augmentation systems (GBAS) have been widely used.

[0003] SBAS systems include BDSBAS, WAAS, MSAS, EGNOS, SDCM, GAGAN, etc. They process satellite signals from ground stations, calculate error correction products and integrity information based on the space state domain (SSR), and broadcast them to end users via geostationary orbit satellites. SBAS systems have a wide coverage area and do not require network coverage.

[0004] The GBAS system uses the local difference method to monitor satellite signals and estimate ionospheric delay, tropospheric delay, multipath effect, etc., to construct error correction products based on the observation value domain (OSR), and broadcast them to users through communication links. Users use differential positioning to correct observation value errors using the received OSR correction information and achieve high-precision positioning.

[0005] However, various error correction products have certain limitations when used, and traditional differential positioning methods usually only use a single error correction product to assist the GNSS system in positioning, which cannot meet the different positioning needs of users in various scenarios. Summary of the invention

[0006] The purpose of the present invention is to provide a satellite-based ground-based augmentation integrated differential GNSS real-time PNT method and device, which can flexibly select satellite-based augmentation and ground-based augmentation products according to actual conditions, form a variety of different types of positioning modes, break the limitations of existing positioning modes, improve the accuracy and reliability of navigation positioning and timing, and meet the positioning needs of users in complex scenarios.

[0007] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is:

[0008] A first aspect of an embodiment of the present invention provides a satellite-based integrated differential GNSS real-time PNT method, comprising:

[0009] Obtain configuration files, phase and pseudorange observations of the rover, phase and pseudorange observations of the reference station, broadcast ephemeris and enhanced service products;

[0010] Select the observation type corresponding to GNSS real-time PNT based on the configuration file, the phase observation value and pseudo-range observation value of the rover and the phase observation value and pseudo-range observation value of the reference station;

[0011] Based on the observation value type corresponding to the GNSS real-time PNT, calculate the differential observation value corresponding to the GNSS real-time PNT;

[0012] Determine the availability of the enhanced service product, and correct the GNSS real-time PNT error based on the broadcast ephemeris, the availability of the enhanced service product and the differential observation value corresponding to the GNSS real-time PNT, so as to perform real-time dynamic enhancement of the GNSS real-time PNT based on the satellite base.

[0013] Optionally, based on the configuration file, the phase observation value and pseudorange observation value of the rover and the phase observation value and pseudorange observation value of the reference station, the observation value type corresponding to the GNSS real-time PNT is selected, including:

[0014] If the configuration file is set to enter code-only mode, the pseudorange observation values ​​of the rover and the reference station are used;

[0015] If the configuration file is set to enter phase-dominant mode, the phase observations and pseudorange observations of the rover and the phase observations and pseudorange observations of the reference station are used.

[0016] Optionally, based on the observation value type corresponding to the GNSS real-time PNT, calculating the differential observation value corresponding to the GNSS real-time PNT includes:

[0017] If the code-only mode is used, the inter-station single difference and inter-satellite single difference of the pseudo-range observation values ​​are calculated to form differential pseudo-range observation values;

[0018] If the phase-dominant mode is used, the inter-station single difference and inter-satellite single difference of the pseudorange observation values ​​are calculated to form the differential pseudorange observation values, and the inter-station single difference and inter-satellite single difference of the phase observation values ​​are calculated to form the differential phase observation values;

[0019] Among them, the inter-station single difference is the difference between the pseudorange observation value / phase observation value of the mobile station and the pseudorange observation value / phase observation value of the reference station; the inter-satellite single difference refers to the difference between the pseudorange observation value / phase observation value of the reference satellite and the pseudorange observation value / phase observation value of the common view satellite.

[0020] Optionally, determining the availability of the enhanced service product, and correcting the GNSS real-time PNT error according to the broadcast ephemeris, the availability of the enhanced service product, and the differential observation value corresponding to the GNSS real-time PNT, so as to perform satellite-based real-time dynamic enhancement of the GNSS real-time PNT, including:

[0021] In code-only mode:

[0022] Based on the first function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated;

[0023] If the availability status of the augmentation service product is that the satellite-based augmentation product is available, the differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated and eliminated using the error correction technology. At the same time, the differential satellite orbit error or differential ionospheric delay or differential tropospheric delay is corrected by the satellite-based augmentation product to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch;

[0024] If the availability status of the augmentation service product is that the ground-based augmentation product is available, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product, and the differential satellite orbit error is corrected by broadcast ephemeris to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch;

[0025] If the augmentation service product is available in the state that satellite-based augmentation products and ground-based augmentation products are available, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product, and the differential satellite orbit error or differential ionospheric delay or differential tropospheric delay is corrected through the satellite-based augmentation product to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch;

[0026] If the enhanced service product availability status is unavailable, the error correction technology is used to calculate and eliminate the differential ionospheric delay, differential tropospheric delay and differential multipath effect. At the same time, the differential satellite orbit error is corrected by broadcast ephemeris to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0027] Optionally, the first function model is:

[0028]

[0029] In the formula, superscripts s and g represent reference satellites and common-view satellites, respectively, and subscripts r, q, and f represent reference stations, mobile stations, and frequencies, respectively. and Δ represent the inter-satellite difference and inter-station difference respectively, represents the differential pseudorange observation value, represents the differential distance between the receiver and the satellite, represents the differential satellite orbit error, represents the differential ionospheric delay, represents the differential tropospheric delay, represents the differential pseudorange multipath effect, represents the noise of differential pseudorange observations.

[0030] Optionally, determining the availability of the enhanced service product, and correcting the GNSS real-time PNT error according to the broadcast ephemeris, the availability of the enhanced service product, and the differential observation value corresponding to the GNSS real-time PNT, so as to perform satellite-based real-time dynamic enhancement of the GNSS real-time PNT, including:

[0031] In phase-dominant mode:

[0032] Based on the second function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated;

[0033] If the availability status of the augmentation service product is that the satellite-based augmentation product is available, the differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated and eliminated using the error correction technology. At the same time, the differential satellite orbit error or differential ionospheric delay or differential tropospheric delay is corrected by the satellite-based augmentation product to obtain the differential phase observation value and the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch;

[0034] If the availability status of the augmentation service product is that the ground-based augmentation product is available, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product, and the differential satellite orbit error is corrected by broadcast ephemeris to obtain the differential phase observation value and differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch;

[0035] If the augmentation service product is available in the state that satellite-based augmentation products and ground-based augmentation products are available, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product, and the differential satellite orbit error or differential ionospheric delay or differential tropospheric delay is corrected through the satellite-based augmentation product to obtain the differential phase observation value and the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch;

[0036] If the enhanced service product availability status is unavailable, the error correction technology is used to calculate and eliminate the differential ionospheric delay, differential tropospheric delay and differential multipath effect. At the same time, the differential satellite orbit error is corrected by broadcast ephemeris to obtain differential phase observations and differential pseudorange observations, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0037] Optionally, the second function model is:

[0038]

[0039] ; where superscripts s and g represent reference satellites and common-view satellites, respectively, and subscripts r, q, and f represent reference stations, mobile stations, and frequencies, respectively. and Δ represent the inter-satellite difference and inter-station difference respectively, represents the differential pseudorange observation value, represents the differential phase observation value, represents the differential distance between the receiver and the satellite, represents the differential satellite orbit error, represents the differential ionospheric delay, λ f represents the wavelength of the phase observation at frequency f, represents the differential integer ambiguity, represents the differential tropospheric delay, represents the differential pseudorange multipath effect, represents the noise of differential pseudorange observations, represents the differential phase multipath effect, represents the difference phase observation noise.

[0040] In a second aspect of an embodiment of the present invention, there is also provided a satellite-based enhanced integrated differential GNSS real-time PNT device, including:

[0041] A data acquisition module is used to obtain configuration files, phase observations and pseudorange observations of mobile stations, phase observations and pseudorange observations of reference stations, broadcast ephemeris and enhanced service products;

[0042] A mode selection module is used to select the observation type corresponding to the GNSS real-time PNT according to the configuration file, the phase observation value and pseudo-range observation value of the mobile station and the phase observation value and pseudo-range observation value of the reference station;

[0043] An observation value calculation module, used for calculating the differential observation value corresponding to the GNSS real-time PNT based on the observation value type corresponding to the GNSS real-time PNT;

[0044] The correction and enhancement module is used to determine the availability of the enhancement service product, and to correct the GNSS real-time PNT error according to the broadcast ephemeris, the availability of the enhancement service product and the differential observation value corresponding to the GNSS real-time PNT, so as to perform real-time dynamic enhancement of the GNSS real-time PNT based on the satellite base.

[0045] The present invention has the following beneficial effects:

[0046] (1) Enhanced positioning accuracy: The present invention significantly improves the accuracy of GNSS real-time PNT by fusing satellite-based and ground-based augmentation data, which is extremely critical for application scenarios that require high-precision positioning.

[0047] (2) Real-time data processing capability: The present invention has real-time data processing capability and can quickly correct errors in GNSS signals to ensure that users can obtain accurate positioning information even in a dynamic environment.

[0048] (3) Comprehensiveness of error correction: The present invention comprehensively considers multiple error factors, including satellite orbit error, ionospheric and tropospheric delays, multipath effects, etc., to achieve all-round error correction.

[0049] (4) System compatibility and flexibility: The present invention is compatible with a variety of GNSS systems and can flexibly adjust positioning strategies according to different application requirements and environmental conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings:

[0051] Figure 1 A schematic diagram of the process of the satellite-based enhanced integrated differential GNSS real-time PNT method provided in an embodiment of the present application;

[0052] Figure 2A schematic diagram of a flow chart of a satellite-based enhanced integrated differential GNSS real-time PNT method provided in another embodiment of the present application;

[0053] Figure 3 A schematic diagram of the structure of a satellite-based enhanced integrated differential GNSS real-time PNT device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0054] The following will be combined with the attached embodiment of the present invention Figure 1-3 , the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0055] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0056] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0057] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0058] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0059] Reference Figure 1 , Figure 1 A schematic diagram of a flow chart of a satellite-based augmented integrated differential GNSS real-time PNT method provided in an embodiment of the present application, the method comprising the following steps:

[0060] S100, obtaining a configuration file, phase observation values ​​and pseudorange observation values ​​of a mobile station, phase observation values ​​and pseudorange observation values ​​of a reference station, broadcast ephemeris, and enhanced service products;

[0061] It should be noted that the satellite-based enhanced integrated differential GNSS real-time PNT method provided in the present application provides a positioning method based on phase observation values ​​and / or pseudorange observation values ​​respectively.

[0062] PNT is the acronym for Positioning, Navigation and Timing.

[0063] Configuration files are files used to set and adjust software, hardware devices or system parameters. In the field of satellite navigation, configuration files may contain receiver parameter settings, such as data sampling rate, satellite system selection, positioning mode, coordinate system, cut-off altitude angle, etc. These settings ensure that the receiver can work according to established standards or user requirements.

[0064] A reference station is a station with known precise coordinates and fixed for a long period of time.

[0065] A mobile station refers to a location that is not fixed and requires coordinate information.

[0066] Reference satellites refer to one or more satellites with high signal quality, precise orbit parameters and great contribution to user equipment positioning that are usually selected as reference satellites in GNSS measurements.

[0067] A commonly viewed satellite is a satellite that is observed by multiple receivers.

[0068] The pseudorange observation value refers to the product of the satellite signal propagation time and the signal propagation speed calculated by the receiver after receiving the signal from the satellite, that is, the approximate distance between the mobile station and the satellite. Because this distance is affected by clock error, tropospheric delay, ionospheric delay and many other factors, it is different from the "real distance" between the satellite and the receiver, so it is called a pseudorange observation value.

[0069] The phase observation value refers to the phase difference between the phase generated by the receiver's own oscillation and the received satellite carrier, which is determined by measuring the phase change of the satellite signal during the propagation process. The phase difference multiplied by the signal wavelength can obtain a very accurate distance between the receiver and the satellite, reflecting the relative position relationship between the satellite and the receiver.

[0070] The pseudorange / phase observations of the reference station / rover refer to the pseudorange / phase observations obtained by placing the receiver at the reference station / rover. The pseudorange / phase observations of the reference satellite / common-view satellite refer to the pseudorange / phase observations obtained by receiving the signal from the reference satellite / common-view satellite.

[0071] Broadcast ephemeris: It is determined and provided by the ground control part of the global positioning system and publicly broadcast to global users via GPS satellites. It contains satellite orbit parameters, clock error parameters and other related information. After receiving this information, users can use it to calculate the satellite's position and clock error, thereby improving positioning accuracy.

[0072] The availability status of enhanced service products refers to the ability and status of accessing and using various GNSS enhanced service products. Enhanced service products include but are not limited to: satellite-based augmentation products, ground-based augmentation products, etc., which improve the accuracy and reliability of GNSS real-time PNT by providing error correction information. Among them, satellite-based augmentation products include but are not limited to BDS's B2b / B1C / B2a messages, Galileo's HAS services, SSR's real-time precise orbits, SSR's real-time atmospheric products, etc.; ground-based augmentation products include but are not limited to SSR and OSR products. When the availability status of enhanced service products is displayed as "Available", it means that these correction information can be received and used to improve the quality of positioning results.

[0073] S200, selecting an observation value type corresponding to the GNSS real-time PNT according to the configuration file, the phase observation value and pseudo-range observation value of the mobile station, and the phase observation value and pseudo-range observation value of the reference station;

[0074] GNSS real-time PNT modes include but are not limited to: code-only mode and phase-dominant mode.

[0075] The code-only mode is based on pseudo-range observations for positioning. Pseudo-range observations have a large code width and low accuracy, and are affected by station-related, atmosphere-related, and satellite-related errors. Therefore, the positioning accuracy is generally low and is usually used in general positioning application scenarios.

[0076] The phase-dominant mode uses phase observations for positioning. Since the wavelength of phase observations is short, its observation accuracy is high, reaching the millimeter level, and is usually used in high-precision positioning application scenarios.

[0077] In practical applications, the phase-dominant mode can achieve higher positioning accuracy, which is suitable for application scenarios with high accuracy requirements. The code-only mode can achieve simpler and more economical positioning, which is suitable for application scenarios with relatively low accuracy requirements. The specific solution to be selected depends on the accuracy requirements of the application scenario and the available observation data and correction products.

[0078] In one embodiment, step S200 includes:

[0079] S210, if the configuration file is set to enter code-only mode, the pseudorange observation values ​​of the rover station and the pseudorange observation values ​​of the reference station are used;

[0080] S220: If the configuration file is set to enter phase-dominant mode, the phase observation value and pseudo-range observation value of the mobile station and the phase observation value and pseudo-range observation value of the reference station are used.

[0081] Specifically, the process of determining whether to use code-only mode or phase-dominant mode is given below:

[0082] Step 1 (reading the configuration file): First read the configuration file, which may be a text file or a configuration file in a certain format, which contains the GNSS data processing mode settings.

[0083] Step 2 (determine the mode):

[0084] Code-only mode: If the configuration file explicitly specifies the use of code-only mode, code-only mode is used. This mode is relatively simple and has low accuracy, and is suitable for applications that do not require high positioning accuracy.

[0085] Phase-dominant mode: If the configuration file explicitly indicates to use phase-dominant mode, this mode can achieve higher positioning accuracy and is usually used in precision positioning applications.

[0086] S300, calculating a differential observation value corresponding to the GNSS real-time PNT based on the observation value type corresponding to the GNSS real-time PNT;

[0087] In one embodiment, step S300 includes:

[0088] S310, if the code-only mode is adopted, calculating the inter-station single difference and the inter-satellite single difference of the pseudo-range observation value to form a differential pseudo-range observation value;

[0089] S320: If the phase-dominant mode is adopted, the inter-station single difference and the inter-satellite single difference of the pseudorange observation value are calculated to form a differential pseudorange observation value, and the inter-station single difference and the inter-satellite single difference of the phase observation value are calculated to form a differential phase observation value.

[0090] Among them, the inter-station single difference is the difference between the pseudorange observation value / phase observation value of the mobile station and the pseudorange observation value / phase observation value of the reference station; the inter-satellite single difference refers to the difference between the pseudorange observation value / phase observation value of the reference satellite and the pseudorange observation value / phase observation value of the common view satellite.

[0091] S400, determining the availability status of the enhanced service product, and correcting the GNSS real-time PNT error according to the broadcast ephemeris, the availability status of the enhanced service product and the differential observation value corresponding to the GNSS real-time PNT, so as to perform satellite-based real-time dynamic enhancement of the GNSS real-time PNT.

[0092] It should be noted that according to different scenarios and needs, users obtain the phase observation values / pseudorange observation values ​​of the mobile station and the phase observation values / pseudorange observation values ​​of the reference station, and calculate the differential observation values ​​corresponding to the GNSS real-time PNT. Then, according to the available status of the enhanced service products, users flexibly select satellite-based augmentation products, ground-based augmentation products and broadcast ephemeris, thereby refining them into new and different positioning modes to meet the user location service needs in complex application scenarios and realize high-precision and high-reliability navigation and positioning services.

[0093] It should be noted that each mode is based on the RTD mode or RTK mode, and flexibly selects GBAS and GBAS service products, or does not select them, thus forming the following 8 positioning modes.

[0094] The following is a detailed introduction to some professional terms that need to be used in the 8 positioning modes:

[0095] RTK (Real-time Kinematic) positioning technology is a satellite navigation positioning technology. When performing RTK measurement, the receiver located at the reference station broadcasts the carrier phase observation value and known station coordinates to the mobile station in real time through the data communication link. Based on the carrier phase observation values ​​of the reference station and the mobile station, the RTK data processing software can be used to perform real-time relative positioning, eliminate or weaken errors such as ionospheric delay, tropospheric delay and multipath effect, and then obtain the three-dimensional coordinates of the mobile station and estimate the accuracy.

[0096] RTD (Real-time Differenced) positioning technology is a satellite navigation positioning technology. It is similar to RTK, but uses code pseudo-range observations for differential processing. Due to the large code element width of the ranging code and the low accuracy of the code pseudo-range observations, the accuracy of RTD is generally not as good as RTK, usually at the meter level.

[0097] SBAS (Satellite-Based Augmentation System) is an enhancement service of GNSS. It sends differential correction information, integrity data and other related information to users through geostationary Earth Orbit (GEO) satellites to correct or eliminate ionospheric delay, tropospheric delay and satellite orbit error in GNSS signals.

[0098] GBAS (Ground-Based Augmentation System) is a GNSS augmentation service, but unlike SBAS, GBAS provides correction information through a network of ground base stations. These ground base stations obtain the errors of GNSS signals and send the correction data to users through the communication network. GBAS is usually used for regional augmentation services, which can provide users with sub-meter to centimeter-level positioning accuracy, and is suitable for applications such as precision agriculture, construction, surveying and mapping, and vehicle navigation.

[0099] In one embodiment, SBAS (Satellite-Based Augmentation System) includes but is not limited to: WAAS (Wide Area Augmentation System), EGNOS (European Geostationary Navigation Overlay Service), MSAS (Multi-Functional Satellite Augmentation System), GAGAN (GPS Aided Geo Augmented Navigation), SDCM (System for Differential Corrections and Monitoring) and BDSBAS (Beidou Satellite-Based Augmentation System), which is not specifically limited in the embodiment of the present invention.

[0100] In one embodiment, GBAS (Ground-Based Augmentation System) includes but is not limited to services based on ground reference station networks, such as reference stations in IGS (International GNSS Service) and EPN (European Permanent Network) networks that support ground-based augmentation system data sources, and special ground-based augmentation systems such as LAAS (Local Area Augmentation System). The embodiment of the present invention does not specifically limit this.

[0101] Error correction techniques include, but are not limited to: empirical models, parameter estimation and linear combinations, or comprehensive processing methods.

[0102] The empirical models include, but are not limited to, the Klobuchar model and the International Reference Ionosphere Model for ionospheric correction. The Klobuchar model is an empirical model for reducing ionospheric delays. It uses a single-layer ionosphere model and is calculated using ionospheric parameters in the broadcast ephemeris to reduce ionospheric delays; the Saastamoinen model and the Hopfield model for tropospheric corrections. The Saastamoinen model describes the characteristics and propagation effects of the troposphere based on factors such as temperature, pressure, and hydrometeors.

[0103] Parameter estimates include, but are not limited to, wet delay estimates for tropospheric corrections in the zenith direction.

[0104] Linear combinations include, but are not limited to, ionosphere-free combinations.

[0105] Multipath error correction algorithms include but are not limited to: semi-spherical model or sidereal day filtering. The semi-spherical model uses the spatial repeatability of multipath signals to model multipath and suppress multipath effects. Sidereal day filtering uses the diurnal repeatability of satellite constellations to separate and weaken multipath errors.

[0106] The EKF algorithm is an extended Kalman filter (EKF) algorithm.

[0107] OSR (Observation Space Representation) technology extracts and eliminates errors in the positioning process by accurately measuring and analyzing the satellite signals received by the GNSS receiver. It can also provide differential correction information through the ground reference station network, or use the enhanced information broadcast by the satellite to further improve the positioning accuracy.

[0108] SSR (State Space Representation, based on the space state domain) technology describes the error sources in GNSS positioning by constructing a state space model, separates the error sources and calculates the corresponding correction parameters respectively, and broadcasts them to the user terminal to eliminate or reduce the positioning error, thereby achieving high-precision positioning. It can use the data provided by the ground reference station network and broadcast correction information through satellites.

[0109] The following are the 8 positioning modes:

[0110] The first one (RTD mode): phase observations are not used, only pseudo-range observations are used for differential positioning, there is no enhanced service product, only broadcast ephemeris is used to correct satellite orbit errors, and existing error correction technology is used to correct errors such as ionospheric delay, tropospheric delay and multipath effect, forming the RTD mode.

[0111] Specifically, based on the first function model, the satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated; if the enhanced service product availability status is unavailable, the error correction technology is used to calculate and eliminate the differential ionospheric delay, differential tropospheric delay and differential multipath effect, and at the same time, the differential satellite orbit error is corrected by broadcast ephemeris to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0112] In one embodiment, the first function model is:

[0113] In the formula, superscripts s and g represent reference satellites and common-view satellites, respectively, and subscripts r, q, and f represent reference stations, mobile stations, and frequencies, respectively. and Δ represent the inter-satellite difference and inter-station difference respectively, represents the differential pseudorange observation value, represents the differential distance between the receiver and the satellite, represents the differential satellite orbit error, represents the differential ionospheric delay, represents the differential tropospheric delay, represents the differential pseudorange multipath effect, represents the noise of differential pseudorange observations.

[0114] The second type (GBA-RTD mode): phase observations are not used, only pseudo-range observations are used for differential positioning, and only broadcast ephemeris is used to correct satellite orbit errors. GBAS is used to correct ionospheric delay, tropospheric delay, and multipath effects based on RTD, forming a ground-based enhanced GBA-RTD mode. OSR products and / or SSR products can be used to correct non-modeled errors such as atmospheric related errors.

[0115] Specifically, based on the first function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated. If the available status of the enhanced service product is that the ground-based augmentation product can be obtained, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product. At the same time, the differential satellite orbit error is corrected by the broadcast ephemeris to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0116] The third type (SBA-RTD mode): phase observations are not used, only pseudo-range observations are used for differential positioning, and errors such as ionospheric delay, tropospheric delay and multipath effect are corrected by using empirical models, parameter estimation and linear combination. On the basis of RTD, SBAS is used to correct satellite orbit errors, ionospheric delay and tropospheric delay, forming a satellite-based enhanced SBA-RTD mode. Among them, the orbit error of BDS's B2b / B1C / B2a message, Galileo's HAS service, SSR's real-time precise orbit correction, and SSR's real-time atmospheric correction products are used to correct ionospheric delay or tropospheric delay, forming different SBA-RTD modes.

[0117] Specifically, based on the first function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated. If the available status of the enhanced service product is that the satellite-based augmentation product can be obtained, the error correction technology is used to calculate and eliminate the differential ionospheric delay, differential tropospheric delay and differential multipath effect. At the same time, the differential satellite orbit error or the differential ionospheric delay or the differential tropospheric delay is corrected by the satellite-based augmentation product to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0118] The fourth mode (SGBA-RTD mode): phase observations are not used, and only pseudorange observations are used for differential positioning. On the basis of RTD, SBAS and GBAS are used to correct errors such as satellite orbit, ionospheric delay, tropospheric delay and multipath effect, forming the SGBA-RTD mode with satellite-ground collaborative enhancement.

[0119] Specifically, based on the first function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated. If the available status of the enhanced service product is that the ground-based augmentation product can be obtained, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product. At the same time, the differential satellite orbit error is corrected by the broadcast ephemeris to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0120] The fifth type (RTK mode): uses phase observations and pseudorange observations for differential positioning. There is no enhanced service product. Only the broadcast ephemeris is used to correct satellite orbit errors, clock errors, etc. The existing error correction technology is used to correct errors such as ionospheric delay, tropospheric delay and multipath effect to form the RTK mode.

[0121] Specifically, based on the second function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated. If the enhanced service product availability status is unavailable, the error correction technology is used to calculate and eliminate the differential ionospheric delay, differential tropospheric delay and differential multipath effect. At the same time, the differential satellite orbit error is corrected by broadcast ephemeris to obtain differential phase observations and differential pseudorange observations, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0122] In one embodiment, the second function model is:

[0123]

[0124] ; where superscripts s and g represent reference satellites and common-view satellites, respectively, and subscripts r, q, and f represent reference stations, mobile stations, and frequencies, respectively. and Δ represent the inter-satellite difference and inter-station difference respectively, represents the differential pseudorange observation value, represents the differential phase observation value, represents the differential distance between the receiver and the satellite, represents the differential satellite orbit error, represents the differential ionospheric delay, λ f represents the wavelength of the phase observation at frequency f, represents the differential integer ambiguity, represents the differential tropospheric delay, represents the differential pseudorange multipath effect, represents the noise of differential pseudorange observations, represents the differential phase multipath effect, represents the difference phase observation noise.

[0125] The sixth type (GBA-RTK mode): differential positioning is performed using phase observations and pseudorange observations, and only the broadcast ephemeris is used to correct satellite orbits, etc. Based on RTK, GBAS is used to correct errors such as ionospheric delay, tropospheric delay, and multipath effects, forming a ground-based enhanced GBA-RTK mode. OSR products and / or SSR products can be used to correct non-modeled errors such as atmospheric related errors.

[0126] Specifically, based on the second function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated. If the available status of the enhanced service product is that the ground-based augmentation product can be obtained, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product. At the same time, the differential satellite orbit error is corrected by the broadcast ephemeris to obtain the differential phase observation value and the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0127] The seventh type (SBA-RTK mode): differential positioning is performed using phase observations and pseudorange observations, and errors such as ionospheric delay, tropospheric delay and multipath effect are corrected using empirical models, parameter estimation and linear combination. On the basis of RTK, SBAS is used to correct satellite orbit errors, ionospheric delay and tropospheric delay, forming a satellite-based enhanced SBA-RTK mode. Among them, BDS's B2b / B1C / B2a messages, Galileo's HAS services, SSR's real-time precise orbit correction orbit errors, and SSR's real-time atmospheric correction products are used to correct ionospheric delay or tropospheric delay, forming different SBA_RTK modes.

[0128] Specifically, based on the second function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated. If the available status of the enhanced service product is that the ground-based augmentation product can be obtained, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product. At the same time, the differential satellite orbit error is corrected by the broadcast ephemeris to obtain the differential phase observation value and the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0129] The eighth type (SGBA-RTK mode): phase observations and pseudorange observations are used for differential positioning. On the basis of RTK, SBAS and GBAS are used to correct errors such as satellite orbit, ionospheric delay, tropospheric delay and multipath effect, forming the SGBA-RTK mode with satellite-ground collaborative enhancement.

[0130] Specifically, based on the second function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated. If the available status of the enhanced service product is that satellite-based augmentation products and ground-based augmentation products are available, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product, and the differential satellite orbit error or differential ionospheric delay or differential tropospheric delay is corrected through the satellite-based augmentation product to obtain differential phase observations and differential pseudorange observations, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

[0131] In order to facilitate understanding of the technical solution of the present invention, a specific embodiment is given below:

[0132] In the first aspect, the present invention provides a satellite-based integrated differential GNSS real-time PNT method and device based on pseudo-range observations ( Figure 2 Right), including:

[0133] 1.1 Obtain reference station data, rover data, broadcast ephemeris and configuration files.

[0134] 1.2 According to the configuration file settings, determine whether phase observations are needed. If the code-only (pseudorange observation-based) mode is set, only the pseudorange observations of the reference station and mobile station are obtained, and then the corresponding differential observations are obtained.

[0135] 1.3 The user determines whether there are satellite-based augmentation products in the available data information. If there are satellite-based augmentation products, the user can flexibly select the appropriate satellite orbit correction method according to the type of satellite-based augmentation products. The B2b / B1C / B2a message of BDS, the HAS service of Galileo, the real-time precise orbit product of SSR can be used to correct the satellite orbit error, and the real-time atmospheric correction product of SSR can be used to correct the ionospheric delay or tropospheric delay; if there are no satellite-based augmentation products, only the broadcast ephemeris can be used to correct the satellite orbit error.

[0136] 1.4 The user determines whether there is a foundation reinforcement product in the available data information. If there is a foundation reinforcement product, proceed to step 1.4.1; if the user cannot obtain the foundation reinforcement product, proceed to step 1.4.2;

[0137] 1.4.1 If the user can obtain ground-based augmentation products, then according to the product type, the ground-based augmentation products are used to weaken the ionospheric delay, tropospheric delay or multipath effect, and any number of reference stations can use ground-based augmentation products. Among them, the residual errors such as non-modeled errors can be corrected according to the OSR product, and the modeled errors such as ionospheric delay and tropospheric delay can be corrected by SSR. Then, the receiver coordinates are estimated epoch by epoch based on EKF, and then the satellite-ground augmented RTD (SGBA-RTD) or ground-based augmented RTD (GBA-RTD) mode is formed.

[0138] 1.4.2 If the user cannot obtain ground-based augmentation products, the Klobuchar model is used to correct the ionospheric delay, or the ionospheric delay is eliminated by ionosphere-free combination; the tropospheric delay is calculated using empirical models such as Hopfield and Saastamoinen, or it is set as an unknown parameter for estimation; the multipath effect is processed using the semi-spherical model or sidereal day filter. Then, the receiver coordinates are estimated based on the EKF epoch-by-epoch estimation, and then the satellite-based augmented RTD (SBA-RTD) or RTD mode is formed.

[0139] In the second aspect, the present invention implements a satellite-based integrated differential GNSS real-time PNT method and device based on phase observation values ​​( Figure 2 Left), including:

[0140] 2.1 Obtain reference station data, rover data, broadcast ephemeris and configuration files.

[0141] 2.2 According to the configuration file settings, determine whether phase observations are needed. If the phase-dominant mode is set, obtain the phase observations and pseudorange observations of the reference station and mobile station, and then obtain the corresponding differential observations.

[0142] 2.3 The user determines whether there are satellite-based augmentation products in the available data information. If there are satellite-based augmentation products, the user can flexibly select the appropriate satellite orbit correction method according to the type of satellite-based augmentation products. Among them, the B2b / B1C / B2a message of BDS, the HAS service of Galileo, the real-time precise orbit of SSR and other products can be used to correct satellite orbit errors, and the real-time atmospheric correction products of SSR can be used to correct ionospheric delay or tropospheric delay; if there are no satellite-based augmentation products, only the broadcast ephemeris can be used to correct satellite orbit errors.

[0143] 2.4 The user determines whether there is a foundation reinforcement product in the available data information. If there is a foundation reinforcement product, proceed to step 2.4.1; if the user cannot obtain the foundation reinforcement product, proceed to step 2.4.2;

[0144] 2.4.1 If the user can obtain ground-based augmentation products, then according to the product type, the ground-based augmentation products can be used to weaken the ionospheric delay, tropospheric delay or multipath effect, and any number of reference stations can use ground-based augmentation products. Among them, the residual errors such as non-modeled errors can be corrected according to the OSR product, and the modeled errors such as ionospheric delay and tropospheric delay can be corrected according to the SSR. Then, the receiver coordinates are estimated based on the EKF epoch by epoch, thereby forming the satellite-ground augmented RTK (SGBA-RTK) or ground-based augmented RTK (GBA-RTK) mode.

[0145] 2.4.2 If the user cannot obtain ground-based augmentation products, the Klobuchar model is used to correct the ionospheric delay, or the ionospheric delay is eliminated by ionosphere-free combination; the tropospheric delay is calculated using empirical models such as Hopfield and Saastamoinen, or it is set as an unknown parameter for estimation, and the multipath effect is processed using the semi-spherical model or sidereal day filter. Then, the receiver coordinates are estimated based on the EKF epoch-by-epoch estimation, and then the satellite-based augmented RTK (SBA-RTK) or RTK mode is formed.

[0146] It should be noted that more modes can be subdivided depending on the satellite-based augmentation products and ground-based augmentation products used.

[0147] In summary, users can flexibly select satellite orbit products, various OSR and SSR products to perform real-time dynamic enhancement of satellite base according to their actual needs and the enhanced service products they can obtain. Based on the above two aspects, various positioning modes are formed to meet the positioning needs of different users.

[0148] The present invention has the following beneficial effects:

[0149] (1) Enhanced positioning accuracy: The present invention significantly improves the accuracy of GNSS real-time PNT by fusing satellite-based and ground-based augmentation data, which is extremely critical for application scenarios that require high-precision positioning.

[0150] (2) Real-time data processing capability: The present invention has real-time data processing capability and can quickly correct errors in GNSS signals to ensure that users can obtain accurate positioning information even in a dynamic environment.

[0151] (3) Comprehensiveness of error correction: The present invention comprehensively considers multiple error factors, including satellite orbit error, ionospheric and tropospheric delays, multipath effects, etc., to achieve all-round error correction.

[0152] (4) System compatibility and flexibility: The present invention is compatible with a variety of GNSS systems and can flexibly adjust positioning strategies according to different application requirements and environmental conditions.

[0153] Based on the same inventive concept, Figure 3 The embodiment of the present invention further provides a satellite-based enhanced integrated differential GNSS real-time PNT device 200, comprising:

[0154] A data acquisition module 210 is used to acquire configuration files, phase observations and pseudorange observations of the rover, phase observations and pseudorange observations of the reference station, broadcast ephemeris, and enhanced service products;

[0155] A mode selection module 220, configured to select an observation type corresponding to the GNSS real-time PNT according to the configuration file, the phase observation value and pseudo-range observation value of the rover, and the phase observation value and pseudo-range observation value of the reference station;

[0156] An observation value calculation module 230, configured to calculate a differential observation value corresponding to the GNSS real-time PNT based on an observation value type corresponding to the GNSS real-time PNT;

[0157] The correction and enhancement module 240 is used to determine the availability of the enhancement service product, and correct the GNSS real-time PNT error according to the broadcast ephemeris, the availability of the enhancement service product and the differential observation value corresponding to the GNSS real-time PNT, so as to perform real-time dynamic enhancement of the GNSS real-time PNT based on the satellite base.

[0158] It should be understood that the device corresponds to the above-mentioned satellite-based enhanced integrated differential GNSS real-time PNT method embodiment, and can execute the various steps involved in the above-mentioned method embodiment. The specific functions of the device can be found in the description above. To avoid repetition, the detailed description is appropriately omitted here. The device includes at least one software function module that can be stored in a memory in the form of software or firmware or solidified in the operating system (OS) of the device.

[0159] The above embodiments are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations, modifications, and substitutions made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A satellite-based integrated differential GNSS real-time PNT method, characterized in that: include: Obtain configuration files, phase and pseudorange observations of the rover, phase and pseudorange observations of the reference station, broadcast ephemeris and enhanced service products; Select the observation type corresponding to GNSS real-time PNT based on the configuration file, the phase observation value and pseudo-range observation value of the rover and the phase observation value and pseudo-range observation value of the reference station; Based on the observation value type corresponding to the GNSS real-time PNT, calculate the differential observation value corresponding to the GNSS real-time PNT; Determine the availability of the augmented service product, and correct the GNSS real-time PNT error based on the broadcast ephemeris, the availability of the augmented service product and the differential observation value corresponding to the GNSS real-time PNT, so as to perform satellite-based real-time dynamic augmentation of the GNSS real-time PNT; Select the observation type corresponding to GNSS real-time PNT based on the configuration file, the phase observations and pseudorange observations of the rover and the phase observations and pseudorange observations of the reference station, including: If the configuration file is set to enter code-only mode, the pseudorange observation values ​​of the rover and the reference station are used; If the configuration file is set to enter phase-dominant mode, the phase observations and pseudorange observations of the rover and the phase observations and pseudorange observations of the reference station are used.

2. The satellite-based enhanced integrated differential GNSS real-time PNT method according to claim 1, characterized in that: Based on the observation value type corresponding to the GNSS real-time PNT, the differential observation value corresponding to the GNSS real-time PNT is calculated, including: If the code-only mode is used, the inter-station single difference and inter-satellite single difference of the pseudo-range observation values ​​are calculated to form differential pseudo-range observation values; If the phase-dominant mode is used, the inter-station single difference and inter-satellite single difference of the pseudorange observation values ​​are calculated to form the differential pseudorange observation values, and the inter-station single difference and inter-satellite single difference of the phase observation values ​​are calculated to form the differential phase observation values; Among them, the inter-station single difference is the difference between the pseudorange observation value / phase observation value of the mobile station and the pseudorange observation value / phase observation value of the reference station; the inter-satellite single difference refers to the difference between the pseudorange observation value / phase observation value of the reference satellite and the pseudorange observation value / phase observation value of the common view satellite.

3. The satellite-based enhanced integrated differential GNSS real-time PNT method according to claim 2, characterized in that: Determine the availability of the augmented service product, and correct the GNSS real-time PNT error based on the broadcast ephemeris, the availability of the augmented service product, and the differential observation value corresponding to the GNSS real-time PNT, so as to perform satellite-based real-time dynamic augmentation of the GNSS real-time PNT, including: In code-only mode: Based on the first function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated; If the availability status of the augmentation service product is that the satellite-based augmentation product is available, the differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated and eliminated using the error correction technology. At the same time, the differential satellite orbit error or differential ionospheric delay or differential tropospheric delay is corrected by the satellite-based augmentation product to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch; If the availability status of the augmentation service product is that the ground-based augmentation product is available, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product, and the differential satellite orbit error is corrected by broadcast ephemeris to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch; If the augmentation service product is available in the state that satellite-based augmentation products and ground-based augmentation products are available, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product, and the differential satellite orbit error or differential ionospheric delay or differential tropospheric delay is corrected through the satellite-based augmentation product to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch; If the enhanced service product availability status is unavailable, the error correction technology is used to calculate and eliminate the differential ionospheric delay, differential tropospheric delay and differential multipath effect. At the same time, the differential satellite orbit error is corrected by broadcast ephemeris to obtain the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

4. The satellite-based integrated differential GNSS real-time PNT method according to claim 3, characterized in that: The first function model is: In the formula, superscripts s and g represent reference satellites and common-view satellites, respectively, and subscripts r, q, and f represent reference stations, mobile stations, and frequencies, respectively. and Δ represent the inter-satellite difference and inter-station difference respectively, represents the differential pseudorange observation value, represents the differential distance between the receiver and the satellite, represents the differential satellite orbit error, represents the differential ionospheric delay, represents the differential tropospheric delay, represents the differential pseudorange multipath effect, represents the noise of differential pseudorange observations.

5. The satellite-based enhanced integrated differential GNSS real-time PNT method according to claim 2, characterized in that: Determine the availability of the augmented service product, and correct the GNSS real-time PNT error based on the broadcast ephemeris, the availability of the augmented service product, and the differential observation value corresponding to the GNSS real-time PNT, so as to perform satellite-based real-time dynamic augmentation of the GNSS real-time PNT, including: In phase-dominant mode: Based on the second function model, the differential satellite orbit error, differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated; If the availability status of the augmentation service product is that the satellite-based augmentation product is available, the differential ionospheric delay, differential tropospheric delay and differential multipath effect are calculated and eliminated using the error correction technology. At the same time, the differential satellite orbit error or differential ionospheric delay or differential tropospheric delay is corrected by the satellite-based augmentation product to obtain the differential phase observation value and the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch; If the availability status of the augmentation service product is that the ground-based augmentation product is available, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product, and the differential satellite orbit error is corrected by broadcast ephemeris to obtain the differential phase observation value and differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch; If the augmentation service product is available in the state that satellite-based augmentation products and ground-based augmentation products are available, the differential ionospheric delay or differential tropospheric delay or differential multipath effect is calculated and eliminated through the ground-based augmentation product, and the differential satellite orbit error or differential ionospheric delay or differential tropospheric delay is corrected through the satellite-based augmentation product to obtain the differential phase observation value and the differential pseudorange observation value, and the EKF algorithm is used to solve the receiver coordinates of the current epoch; If the enhanced service product availability status is unavailable, the error correction technology is used to calculate and eliminate the differential ionospheric delay, differential tropospheric delay and differential multipath effect. At the same time, the differential satellite orbit error is corrected by broadcast ephemeris to obtain differential phase observations and differential pseudorange observations, and the EKF algorithm is used to solve the receiver coordinates of the current epoch.

6. The satellite-based enhanced integrated differential GNSS real-time PNT method according to claim 5, characterized in that: The second function model is: In the formula, superscripts s and g represent reference satellites and common-view satellites, respectively, and subscripts r, q, and f represent reference stations, mobile stations, and frequencies, respectively. and Δ represent the inter-satellite difference and inter-station difference respectively, represents the differential pseudorange observation value, represents the differential phase observation value, represents the differential distance between the receiver and the satellite, represents the differential satellite orbit error, represents the differential ionospheric delay, λ f represents the wavelength of the phase observation at frequency f, represents the differential integer ambiguity, represents the differential tropospheric delay, represents the differential pseudorange multipath effect, represents the noise of differential pseudorange observations, represents the differential phase multipath effect, represents the difference phase observation noise.

7. A satellite-based integrated differential GNSS real-time PNT device, characterized in that: include: A data acquisition module is used to obtain configuration files, phase observations and pseudorange observations of mobile stations, phase observations and pseudorange observations of reference stations, broadcast ephemeris and enhanced service products; A mode selection module is used to select the observation type corresponding to the GNSS real-time PNT according to the configuration file, the phase observation value and pseudo-range observation value of the mobile station and the phase observation value and pseudo-range observation value of the reference station; An observation value calculation module, used for calculating the differential observation value corresponding to the GNSS real-time PNT based on the observation value type corresponding to the GNSS real-time PNT; The correction and enhancement module is used to determine the availability of the enhancement service product and correct the GNSS real-time PNT error according to the broadcast ephemeris, the availability of the enhancement service product and the differential observation value corresponding to the GNSS real-time PNT, so as to perform satellite-based real-time dynamic enhancement of the GNSS real-time PNT; The mode selection module is specifically used for: If the configuration file is set to enter code-only mode, the pseudorange observation values ​​of the rover and the reference station are used; If the configuration file is set to enter phase-dominant mode, the phase observations and pseudorange observations of the rover and the phase observations and pseudorange observations of the reference station are used.

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