Integrated determination method for low-orbit navigation enhanced satellite orbit and clock error

Abstract

The invention provides a low-orbit navigation enhanced satellite orbit and clock error integrated determination method, which comprises the following steps that: a low-orbit navigation enhanced satellite carries a GNSS (Global Navigation Satellite System) receiver, can receive a multi-system GNSS satellite navigation signal and can issue a navigation enhanced signal at the same time, a downlink signal and a satellite-borne GNSS receiver clock share the same source, and a deviation exists between the clock error and the clock error of the satellite-borne receiver; the satellite-borne observation data of the low-orbit satellite, the GNSS of the ground station and the observation data of the low-orbit satellite are fused, an observation model for fusion processing is given, and the orbit of the low-orbit navigation enhanced satellite, the receiver clock error and the downlink signal time delay deviation are integrally determined. Unified adjustment and parameter joint calculation of satellite-borne and downlink observation values of the low earth orbit satellite are realized.

Description

Technical Field

[0001] This invention relates to the field of satellite navigation and positioning technology, and in particular to a method for determining the orbit and clock bias of a low-Earth orbit navigation enhancement satellite. Background Technology

[0002] High-precision positioning services are at the forefront of applications for Global Navigation Satellite Systems (GNSS). Emerging industries such as intelligent unmanned systems, mobile robots, and autonomous driving are placing higher demands on the real-time performance and accuracy of positioning, navigation, and timing services. Low-Earth orbit (LEO) navigation enhancement is one of the development directions for next-generation GNSS systems. LEO satellites can provide navigation signals with higher power, better anti-interference and anti-spoofing performance, while also optimizing observation geometry. Due to the high speed of LEO satellites, significant geometric changes can occur in a short time. If dozens or even hundreds of LEO satellites transmit navigation signals to the ground in the future, precise point positioning with convergence within seconds can be achieved.

[0003] Accurate LEO satellite orbits and clock bias products are prerequisites for LEO navigation enhancement. Precise Orbit Determination (POD) of LEO satellites based on spaceborne GNSS has the advantages of low cost and high accuracy, and has become one of the mainstream technologies. Regarding orbit determination methods, simplified dynamic orbit determination, based on accurate conservative force models, utilizes scale parameters and empirical acceleration parameters to address the problems of low accuracy of non-conservative force models and complex perturbations in LEO satellites. This achieves orbit results with higher accuracy than dynamic and kinematic methods and has been widely applied in numerous domestic and international LEO satellite scientific missions. When using GNSS precise ephemeris products provided by the International GNSS Service (IGS), the simplified dynamic orbit determination accuracy for LEO satellites can reach up to 1-2 cm. The downlink signal for LEO satellite navigation generally shares a common source with the clock of the spaceborne GNSS receiver. When determining the LEO satellite orbit using spaceborne GNSS technology, the clock bias of the spaceborne receiver can be obtained simultaneously. However, there is a deviation between this and the actual downlink signal clock bias, referred to here as the LEO satellite downlink signal time delay bias. This time delay bias requires close attention in the determination of orbits and clock biases for LEO navigation enhancement satellites. Summary of the Invention

[0004] This invention provides a method for integrated determination of the orbit and clock bias of a low-Earth orbit navigation enhancement satellite, which addresses the deficiencies in existing technologies. It utilizes onboard GNSS data from the low-Earth orbit navigation enhancement satellite and tracking data from ground stations for both the GNSS satellite and the low-Earth orbit navigation enhancement satellite to achieve integrated determination of the low-Earth orbit navigation enhancement satellite's orbit and downlink clock bias.

[0005] In a first aspect, the present invention provides a method for determining the orbit and clock bias of a low-Earth orbit navigation enhancement satellite, comprising: The low-Earth orbit navigation enhancement satellite carries an onboard GNSS receiver to acquire pseudorange and carrier phase observation data transmitted by the GNSS satellite; The ground station is equipped with an enhanced GNSS receiver to receive pseudorange and carrier phase observation data transmitted from GNSS and low-orbit navigation enhancement satellites; Collect GNSS satellite precision orbit and clock bias products distributed by international GNSS service organizations; Based on pseudorange and carrier phase observation data, GNSS satellite precise orbit and clock bias products, a joint orbit determination observation model is constructed and least squares batch processing is performed to obtain the orbit, receiver clock bias and downlink signal delay deviation of the low-orbit navigation enhancement satellite.

[0006] According to the present invention, a method for determining the orbit and clock bias of a low-Earth orbit navigation enhancement satellite is provided, wherein the low-Earth orbit navigation enhancement satellite has the ability to transmit downlink dual-frequency navigation signals.

[0007] According to the present invention, an integrated method for determining the orbit and clock bias of a low-Earth orbit navigation enhancement satellite is provided, wherein the enhanced GNSS receiver has the ability to capture downlink navigation signals from GNSS satellites and low-Earth orbit navigation enhancement satellites.

[0008] According to the present invention, a method for determining the orbit and clock bias of a low-Earth orbit navigation enhancement satellite is provided. This method employs a simplified dynamic orbit determination method and uses onboard GNSS observation data of the low-Earth orbit satellite to determine the low-Earth orbit satellite orbit and receiver clock bias.

[0009] According to the present invention, a method for integrating orbit and clock bias determination of low-Earth orbit navigation enhancement satellites is provided, wherein the joint orbit determination observation model includes:

[0010] Among them, superscript , These represent the designations of GNSS satellites and low-Earth orbit satellites, respectively, with subscripts. , These represent the ground station and the low-Earth orbit satellite, respectively, acting as the signal receiver. and This represents the difference between the observed value and the calculated value, which is the combination of ionospheric delay pseudorange and carrier phase. The corresponding observation noise is represented in meters. This represents the unit vector pointing from the receiver to the satellite. Representative reference time The low-Earth orbit satellite orbital state transition matrix up to the epoch. The orbital parameters representing the reference time include the low-Earth orbit satellite position, velocity, and force model parameters. The clock bias parameter represents the satellite clock bias when indicated by a superscript, and the GPS receiver clock bias when indicated by a subscript. This represents the inter-system bias of other GNSS systems or low-Earth orbit navigation systems (sys). This indicates the downlink signal delay deviation of low-orbit navigation enhancement satellites. Represents the tropospheric projection function. This represents the zenith tropospheric delay, and the station's coordinates are: , and The wavelength and integer ambiguity represent the ionospheric carrier phase observation.

[0011] According to the method for integrated determination of orbit and clock bias of low-Earth orbit navigation enhancement satellite provided by the present invention, the GPS receiver clock bias of the low-Earth orbit navigation enhancement satellite, as well as the inter-system bias (ISB) between other GNSS systems and GPS, are estimated epoch-by-epoch using white noise.

[0012] According to the method for integrated determination of orbit and clock bias of low-Earth orbit navigation enhancement satellite provided by the present invention, the clock bias of the GPS receiver of the ground station is estimated as white noise epoch by epoch, and the ISB between the low-Earth orbit navigation system and GPS is estimated as a constant.

[0013] According to the method for integrated determination of orbit and clock bias of low-Earth orbit navigation enhancement satellite provided by the present invention, zero-sum constraints are added to the ISB parameters of the low-Earth orbit navigation system of the ground station to avoid rank deficiency:

[0014] in, Represents the ground station number. This refers to the number of ground stations.

[0015] According to the method for integrated determination of orbit and clock bias of a low-Earth orbit navigation enhancement satellite provided by the present invention, the downlink signal delay deviation parameter of the low-Earth orbit navigation enhancement satellite is estimated as white noise, a random walk process, or a constant, respectively, wherein: The white noise process model is:

[0016]

[0017] The random walk process model is as follows:

[0018]

[0019] The constant model is:

[0020] in, for Prior time delay bias at time, for Posterior time delay bias at time, for Prior variance at time, for The prior and posterior variances at time points. yes The portion of the time delay deviation that varies. For the corresponding variance, Let V be the prior variance of the time delay deviation parameter.

[0021] In a second aspect, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the integrated determination method for low-Earth orbit navigation enhancement satellite orbit and clock bias as described above.

[0022] The integrated method for determining the orbit and clock bias of LEO navigation augmentation satellites provided by this invention takes into account the time delay deviation between signal reception and transmission of LEO navigation augmentation satellites and its impact on precise positioning applications. It constructs an on-orbit calibration method for the time delay deviation of LEO satellite downlink navigation augmentation signals using onboard GNSS observation data from LEO satellites and downlink navigation augmentation data from LEO satellites, conforming to GNSS precise positioning theory. This invention achieves rigorous unified adjustment and parameter calculation of multi-source observation data, realizing the integrated determination of LEO navigation augmentation satellite orbits and downlink clock biases in a rigorous and systematic manner. Applying the integrated determination method provided by this invention, the time delay deviation of LEO navigation augmentation satellite downlink signals can be obtained, providing a foundation for related research. Using the LEO navigation augmentation satellite orbit and clock bias products generated by this invention for precise single-point positioning with LEO satellite augmentation can effectively improve convergence time and positioning accuracy. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is one of the flowcharts illustrating the integrated method for determining the orbit and clock difference of low-Earth orbit navigation enhancement satellites provided by the present invention; Figure 2This is a schematic diagram of the integrated method for determining the orbit and clock bias of low-Earth orbit navigation enhancement satellites provided by the present invention. Figure 3 This is the second flowchart of the method for integrating low-orbit navigation enhancement satellite orbit and clock bias determination provided by the present invention; Figure 4 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0026] To address the limitations of existing technologies, the technical solution provided by this invention utilizes onboard GNSS data from low-Earth orbit (LEO) navigation augmentation satellites and tracking data from ground stations to achieve integrated determination of the LEO navigation augmentation satellite's orbit and downlink clock bias. Using the precise ephemeris of the GNSS satellites provided by the IGS analysis center as a spatiotemporal reference, it integrates onboard GNSS observation data from the LEO navigation augmentation satellites, ground station GNSS observation data, and ground station LEO observation data to comprehensively determine the LEO navigation augmentation satellite's orbit, clock bias, time delay deviation, as well as parameters such as ground station coordinates, receiver clock bias, and tropospheric delay.

[0027] Figure 1 This is one of the flowcharts illustrating the integrated determination method for low-Earth orbit navigation enhancement satellite orbit and clock bias provided in this embodiment of the invention, such as... Figure 1 As shown, it includes: Step 100: The low-Earth orbit navigation augmentation satellite carries an onboard GNSS receiver to acquire pseudorange and carrier phase observation data transmitted by the GNSS satellite; Step 200: The ground station is equipped with an enhanced GNSS receiver to receive pseudorange and carrier phase observation data transmitted from GNSS and low-orbit navigation enhancement satellites; Step 300: Collect GNSS satellite precision orbit and clock bias products distributed by international GNSS service organizations; Step 400: Based on pseudorange, carrier phase observation data, GNSS satellite precise orbit and clock bias products, construct a joint orbit determination observation model and perform least squares batch processing to obtain the orbit, receiver clock bias and downlink signal delay deviation of the low-orbit navigation enhancement satellite.

[0028] like Figure 2As shown, the basic process of this invention is as follows: First, standard single-point positioning is performed using onboard GNSS pseudorange observation data from the low-Earth orbit navigation augmentation satellite and GNSS precise ephemeris provided by the IGS analysis center to obtain low-Earth orbit satellite position and clock bias information with meter-level accuracy. Then, the atmospheric drag scale parameters, solar radiation pressure scale parameters, and empirical acceleration parameters of the low-Earth orbit satellite are fitted using the discrete low-Earth orbit satellite position information to obtain initial values ​​for the aforementioned force model parameters. Next, the onboard GNSS data and satellite-to-ground GNSS / LEO observation data are preprocessed, mainly including cycle slip detection and gross error removal, and the ambiguity parameters are segmented using cycle slip information. Finally, least-squares batch processing is performed using the preprocessed various types of observation data and GNSS precise ephemeris to calculate parameter estimates. After quality control using post-hoc residual information, least-squares calculation is performed again to finally obtain the low-Earth orbit navigation augmentation satellite orbit and clock bias products, which can be directly used for high-precision positioning augmentation for users.

[0029] The method described in this invention relates to simplified dynamic orbit determination for low-Earth orbit (LEO) satellites, requiring a reasonable matching of dynamic and geometric observation information to achieve the optimal solution. The equations of motion for the LEO satellite are as follows:

[0030] in, and These represent the position vector and velocity vector of the low-orbit satellite in the inertial coordinate system, respectively. These represent force model parameters, such as parameters of the light pressure model, empirical acceleration parameters, and atmospheric drag model parameters.

[0031] make and The above formula can be simplified to:

[0032] If initial conditions are already given Therefore, the essence of the satellite's motion equations is a system of nonlinear first-order ordinary differential equations.

[0033] The satellite's reference orbit can be obtained by numerically integrating the satellite's equations of motion. Linearizing the satellite's equations of motion, we can obtain...

[0034] in,

[0035] The above equation can be rearranged as follows: ,make , Then there is ,make The variational equation is as follows:

[0036] in,

[0037] In practice, by using numerical integration methods to solve the equations of motion and variational equations, the transition matrix of the reference orbit and orbit correction at any time can be obtained. Then, the orbit state at any time within the orbit determination arc can be established with the orbit state at the reference time, and the orbit state at the reference time can be improved by adjusting the observation data at any time.

[0038] Specifically, such as Figure 3 As shown, standard point positioning was performed using onboard GNSS pseudorange observation data from low-Earth orbit navigation augmentation satellites and precise GNSS ephemeris data provided by the IGS analysis center. This yielded low-Earth orbit satellite position and clock error information with meter-level accuracy. The ionosphere-free combined observation model is as follows:

[0039] In the formula, superscript Indicates the GNSS satellite number, subscript leo This indicates a low-Earth orbit satellite (acting as a signal receiver). This represents the difference between the observed and calculated values ​​(OMC) of the combined ionospheric delay pseudorange. The corresponding observation noise is represented in meters. This represents the unit vector pointing from the receiver to the satellite. The position parameters representing low-Earth orbit navigation augmentation satellites, The clock bias parameter represents the satellite clock bias when indicated by a superscript, and the GPS receiver clock bias when indicated by a subscript. Representing other GNSS systems sys Inter-system bias.

[0040] Using discrete low-Earth orbit (LEO) satellite position information as virtual observations, we fit the reference epoch position velocity, atmospheric drag scale parameters, solar radiation pressure scale parameters, and empirical acceleration parameters of the LEO satellites to obtain initial values ​​for the aforementioned force model parameters. The observation model is as follows:

[0041] in, , and Represents the position of low-Earth orbit satellites. , and This represents the virtual observation value of the orbit. The above formula can be written as:

[0042] in, , and The reference orbit can be represented by the orbital state and state transition matrix of the reference epoch.

[0043] Preprocessing of spaceborne GNSS data and satellite-to-ground GNSS / LEO observation data mainly includes cycle slip detection and gross error removal, using cycle slip information to segment ambiguity parameters. The cycle slip detection model is as follows:

[0044]

[0045] In the formula, and These represent the wide alley observation value and its wavelength, respectively. and Represents the frequency of the dual-frequency signal. and pseudorange observations, The ambiguity representing the wide alley observation value, For GF phase observations, For ionospheric delay, To measure noise. During adjacent epochs or If the difference exceeds the threshold, it is considered that a cycle jump has occurred in the current epoch, and it is then segmented.

[0046] Least squares batch processing was performed using preprocessed observation data of various types and precise GNSS ephemeris data to obtain parameter estimates. After quality control using post-hoc residual information, least squares calculation was performed again to finally obtain the orbit and clock error products for the LEO navigation augmentation satellite. The orbit determination and clock estimation observation model combining onboard LEO navigation augmentation satellite data and navigation augmentation data is as follows:

[0047] Among them, superscript , These represent the designations of GNSS satellites and low-Earth orbit satellites, respectively, with subscripts. sta , leo These represent the ground station and the low-Earth orbit satellite (as the signal receiver), respectively. and This represents the difference between the observed and calculated values ​​of the combined ionospheric delay pseudorange and carrier phase (OMC). The observed noise of the effect is expressed in meters. This represents the unit vector pointing from the receiver to the satellite. Representative reference time The low-Earth orbit satellite orbital state transition matrix up to the epoch. The orbital parameters representing the reference time include the low-Earth orbit satellite position, velocity, and force model parameters. The clock bias parameter represents the satellite clock bias when indicated by a superscript, and the GPS receiver clock bias when indicated by a subscript. Representing other GNSS systems or low-Earth orbit navigation systems sys Inter-system bias bias This indicates the downlink signal delay deviation of low-orbit navigation enhancement satellites. M Represents the tropospheric projection function. T This represents the zenith tropospheric delay, and the station's coordinates are: , and The wavelength and integer ambiguity represent the ionospheric carrier phase observation.

[0048] For ground-based observation stations and low-Earth orbit (LEO) satellites, GPS receiver clock bias is typically estimated epoch-by-epoch using white noise, while the ISB parameter is handled differently. Ground station receivers operate in a relatively stable environment, so the ISB is estimated as a constant. However, LEO satellites are affected by factors such as receiver inherent limitations and environmental changes, which can cause ISB parameters to fluctuate. Therefore, the ISB parameter is estimated as white noise.

[0049] For ground observation stations, the ISB between the LEO navigation system and GPS is estimated as a constant. To avoid rank deficiency, a baseline constraint is added that the sum of the ISBs of the ground stations is zero. The virtual observation value is:

[0050] in i Represents the ground station number. n This refers to the number of ground stations.

[0051] The downlink signal delay deviation parameter of low-Earth orbit satellites can be used as an estimate of white noise, random walk process, or constant: White noise process model:

[0052]

[0053] Random walk process model:

[0054]

[0055] Constant model:

[0056] In the formula, for Prior time delay bias at time, for Posterior time delay bias at time, for Prior variance at time, for The prior and posterior variances at time points. yes The portion of the time delay deviation that varies. For the corresponding variance, Let V be the prior variance of the time delay deviation parameter.

[0057] Figure 4 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 4 As shown, the electronic device may include: a processor 410, a communication interface 420, a memory 430, and a communication bus 440. The processor 410, communication interface 420, and memory 430 communicate with each other via the communication bus 440. The processor 410 can call logic instructions in the memory 430 to execute an integrated method for determining the orbit and clock bias of a low-Earth orbit navigation enhancement satellite. This method includes: the low-Earth orbit navigation enhancement satellite carrying an onboard GNSS receiver to acquire pseudorange and carrier phase observation data transmitted by the GNSS satellite; the ground station equipped with an enhanced GNSS receiver to receive pseudorange and carrier phase observation data transmitted by the GNSS satellite and the low-Earth orbit navigation enhancement satellite; collecting precise orbit and clock bias products of the GNSS satellite distributed by the International GNSS Service Organization; and constructing a joint orbit determination observation model based on the pseudorange and carrier phase observation data, the precise orbit and clock bias products of the GNSS satellite, and performing least-squares batch processing to obtain the orbit of the low-Earth orbit navigation enhancement satellite, the receiver clock bias, and the downlink signal delay deviation.

[0058] Furthermore, the logical instructions in the aforementioned memory 430 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0059] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0060] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for integrating orbit and clock bias determination of low-Earth orbit navigation enhancement satellites, characterized in that, include: The low-Earth orbit navigation enhancement satellite carries an onboard GNSS receiver to acquire pseudorange and carrier phase observation data transmitted by the GNSS satellite; The ground station is equipped with an enhanced GNSS receiver to receive pseudorange and carrier phase observation data transmitted from GNSS and low-orbit navigation enhancement satellites; Collect GNSS satellite precision orbit and clock bias products distributed by international GNSS service organizations; Based on pseudorange and carrier phase observation data, GNSS satellite precise orbit and clock bias products, a joint orbit determination observation model is constructed and least squares batch processing is performed to obtain the orbit, receiver clock bias and downlink signal delay deviation of the low-orbit navigation enhancement satellite.

2. The method for integrated determination of low-Earth orbit navigation enhancement satellite orbit and clock bias according to claim 1, characterized in that, The low-orbit navigation augmentation satellite has the capability to transmit downlink dual-frequency navigation signals.

3. The method for integrated determination of low-Earth orbit navigation enhancement satellite orbit and clock bias according to claim 1, characterized in that, The enhanced GNSS receiver has the ability to capture downlink navigation signals from GNSS satellites and low-Earth orbit navigation enhancement satellites.

4. The method for integrated determination of low-Earth orbit navigation enhancement satellite orbit and clock bias according to claim 1, characterized in that, A simplified dynamic orbit determination method was adopted, using onboard GNSS observation data from the low-Earth orbit satellite to determine the low-Earth orbit satellite orbit and the receiving clock bias.

5. The method for integrated determination of low-Earth orbit navigation enhancement satellite orbit and clock bias according to claim 1, characterized in that, The joint orbit determination and observation model includes: Among them, superscript , These represent the designations of GNSS satellites and low-Earth orbit satellites, respectively, with subscripts. , These represent the ground station and the low-Earth orbit satellite, respectively, acting as the signal receiver. and This represents the difference between the observed value and the calculated value, which is the combination of ionospheric delay pseudorange and carrier phase. The corresponding observation noise is represented in meters. This represents the unit vector pointing from the receiver to the satellite. Representative reference time The low-Earth orbit satellite orbital state transition matrix up to the epoch. The orbital parameters representing the reference time include the low-Earth orbit satellite position, velocity, and force model parameters. The clock bias parameter represents the satellite clock bias when indicated by a superscript, and the GPS receiver clock bias when indicated by a subscript. This represents the inter-system bias of other GNSS systems or low-Earth orbit navigation systems (sys). This indicates the downlink signal delay deviation of low-orbit navigation enhancement satellites. Represents the tropospheric projection function. This represents the zenith tropospheric delay, and the station's coordinates are: , and The wavelength and integer ambiguity represent the ionospheric carrier phase observation.

6. The method for integrating orbit and clock bias determination of low-Earth orbit navigation enhancement satellites according to claim 1, characterized in that, The GPS receiver clock bias of the low-orbit navigation augmentation satellite, as well as the inter-system bias (ISB) between other GNSS systems and GPS, are estimated epoch-by-epoch using white noise.

7. The method for integrated determination of low-Earth orbit navigation enhancement satellite orbit and clock bias according to claim 1, characterized in that, The clock bias of the GPS receiver at the ground station is estimated as white noise per epoch, and the ISB between the low-orbit navigation system and GPS is estimated as a constant.

8. The method for integrated determination of low-Earth orbit navigation enhancement satellite orbit and clock bias according to claim 1, characterized in that, Add zero-sum constraints to the ISB parameters of the low-orbit navigation system at the ground station to avoid rank deficiency: in, Represents the ground station number. This refers to the number of ground stations.

9. The method for integrated determination of low-Earth orbit navigation enhancement satellite orbit and clock bias according to claim 1, characterized in that, The downlink signal delay deviation parameter of the low-orbit navigation augmentation satellite is estimated as white noise, a random walk process, or a constant, respectively, where: The white noise process model is: The random walk process model is as follows: The constant model is: in, for Prior time delay bias at time, for Posterior time delay bias at time, for Prior variance at time, for The prior and posterior variances at time points. yes The portion of the time delay deviation that varies. For the corresponding variance, Let V be the prior variance of the time delay deviation parameter.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method for determining the integrated orbit and clock bias of low-Earth orbit navigation enhancement satellites as described in any one of claims 1 to 9.

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