Satellite-based enhanced integrity monitoring method and system combined with satellite-earth observation

Abstract

The invention discloses a satellite-based enhanced integrity monitoring method and system combined with satellite-earth observation, and relates to a satellite navigation enhancement technology, and the method comprises the steps: obtaining current epoch observation data; constructing an ionosphere-free combined observation value for the low-orbit star observation data and the ground station observation data; determining a low-orbit star orbit and a clock error according to the low-orbit star and ground station observation data; according to the determined orbit of the low-orbit star and the clock error, calculating a pseudo-range residual error of pseudo-range observation data of the low-orbit star and the ground station; according to the calculated pseudo-range residual error and satellite-earth observation data, calculating a satellite-based enhanced differential correction number; and calculating a satellite-based enhancement integrity parameter according to the calculated satellite-based enhancement differential correction and the satellite-earth observation data. According to the invention, the GNSS monitoring receiver is carried on the low-orbit satellite, and the GNSS observation data of the ground monitoring station and the satellite-borne GNSS observation data of the low-orbit satellite are jointly processed, so that the continuous satellite-based enhanced integrity monitoring of the full flight segmental arc of the GNSS satellite is realized.

Description

Technical Field

[0001] The present application relates to the field of satellite navigation enhancement technology, and in particular to a satellite-based enhanced integrity monitoring method and system for combined satellite and ground observation. Background Art

[0002] The Satellite Based Augmentation System (SBAS) uses a certain number of monitoring stations to continuously track and observe the satellites of the Global Navigation Satellite System (GNSS), and uses observation data such as pseudorange and carrier phase to form differential and integrity information, thereby realizing integrity monitoring of GNSS satellites in the coverage area of ​​the monitoring stations.

[0003] Because the satellite-based augmentation system monitoring stations are distributed regionally, it is difficult to form continuous multiple coverage of the GNSS satellites that are continuously operating around the world, resulting in the inability to continuously monitor the integrity status of the GNSS satellites. Once the satellite leaves the monitoring area, the integrity of the GNSS satellite cannot be monitored.

[0004] At present, the publicly available satellite-based augmentation information processing technologies are all implemented using observation data from a limited number of ground monitoring stations. There is still a lack of methods to use joint satellite-ground observation data to realize integrity monitoring of the entire flight arc of GNSS satellites.

[0005] The current satellite-based enhanced integrity monitoring technology relies on the distribution of ground monitoring stations. Once a GNSS satellite flies out of the observation range of the ground monitoring station, the integrity status of the GNSS satellite cannot be monitored, resulting in the satellite being able to be monitored by satellite-based enhanced integrity monitoring only in a limited flight arc. Summary of the invention

[0006] An embodiment of the present application provides a satellite-based augmented integrity monitoring method and system for joint satellite-ground observation, which carries a GNSS monitoring receiver on a low-orbit satellite, and jointly processes the GNSS observation data of the ground monitoring station and the GNSS observation data onboard the low-orbit satellite, thereby realizing continuous satellite-based augmented integrity monitoring of the entire flight arc of the GNSS satellite.

[0007] The present application embodiment provides a satellite-based enhanced integrity monitoring method for joint satellite-ground observation, including:

[0008] Obtain all low-orbit satellite observation data and ground station observation data in the current epoch;

[0009] For low-orbit satellite observation data and ground station observation data, construct ionosphere-free combined observation values ​​to eliminate ionospheric delay errors;

[0010] Determine the orbit and clock error of the low-orbit satellite based on the observation data of the low-orbit satellite and the ground station;

[0011] According to the determined LEO satellite orbit and clock error and the known coordinates of the ground station, the pseudo-range residuals of the pseudo-range observation data of the LEO satellite and the ground station are calculated;

[0012] Calculate satellite-based enhanced ephemeris and clock differential corrections based on the calculated pseudorange residuals and satellite-to-ground observation data;

[0013] The satellite-based augmentation integrity parameters are calculated based on the calculated satellite-based augmentation ephemeris and clock differential corrections, as well as the satellite-to-earth observation data.

[0014] Optionally, obtaining all low-orbit satellite observation data and ground station observation data of the current epoch also includes: converting all the low-orbit satellite observation data and ground station observation data of the current epoch obtained into a unified format, and eliminating non-current epoch data and data with elevation angles less than the altitude cutoff angle.

[0015] Optionally, for low-orbit satellite observation data and ground station observation data, construct ionosphere-free combined observation values ​​that meet the following requirements:

[0016]

[0017] In the formula, and is the pseudorange and carrier phase observation value of GNSS satellite j observed by low-orbit satellite i after ionosphere-free combination, and P is the pseudorange and carrier phase observation value of GNSS satellite j observed by ground station k after ionospheric-free combination, LEO,i,1 , L LEO,i,1 and P LEO,i,2 , L LEO,i,2 P is the L1 and L5 frequency pseudorange and carrier phase observation value of GNSS satellite j observed by low-orbit satellite i, STA,k,1 , L STA,k,1 and P STA,k,2 , L STA,k,2 are the pseudoranges and carrier phase observations of the L1 and L5 frequency points observed by ground station k, and f1 and f2 are the frequencies of the L1 and L5 frequency points;

[0018] Based on the constructed ionosphere-free combined observations, the corrected LEO pseudorange and carrier phase observations are determined. As well as ground station pseudorange and carrier phase observations

[0019] Optionally, determining the LEO satellite orbit and clock error based on LEO satellite and ground station observation data includes:

[0020] Based on the coordinate information of ground monitoring station k [xSTA,k ,y STA,k ,z STA,k ], all LEO satellite and ground station observation data are processed to determine the orbit and clock error of LEO satellite i:

[0021]

[0022] Where c is the speed of light. Based on formula (2), all observation data at time t are jointly solved and the following parameters are estimated using the least squares method: The orbit O of GNSS satellite j j (t) = [X j (t),Y j (t),Y j (t)] and the clock error δt j (t), the orbit of the low-orbit star i O LEO,i (t) = [x LEO,i (t),y LEO,i (t),z LEO,i (t)] and the clock error δt LEO,i (t), ground station clock error δt STA,k (t), the integer ambiguity of GNSS satellite j observed by low-orbit satellite i The integer ambiguity of GNSS satellite j observed by ground station k

[0023] Optionally, according to the determined LEO satellite orbit and clock error and the known coordinates of the ground station, calculating the pseudorange residuals of the pseudorange observation data of the LEO satellite and the ground station includes:

[0024] Calculate the ephemeris of satellite j at time t using the ephemeris parameters in the navigation message broadcast by the GNSS satellite Combined with the orbit of low-orbit star i at time t [x LEO,i (t),y LEO,i (t),z LEO,i (t)] and the coordinates of ground station k [x STA,k ,y STA,k ,z STA,k ], calculate the geometric distance between low-orbit satellite i and ground station k and GNSS satellite j at time t and

[0025]

[0026] Calculate the clock error of satellite j at time t using the clock error parameters in the navigation message broadcast by the GNSS satellite

[0027]

[0028] For low-orbit satellite observation data, and δtLEO,i (t)From Eliminate the pseudo-range residual of the low-orbit satellite i observation

[0029]

[0030] For ground station observation data, and δt STA,k (t)From P STA,k (t) is eliminated to obtain the pseudorange residual observed by ground station k

[0031]

[0032] Among them, ΔO j (t) is the correction of the real ephemeris of GNSS satellite j relative to the broadcast ephemeris; is the unit direction vector from LEO satellite i and ground station k to GNSS satellite j; ΔT j (t) is the correction of the true clock error of GNSS satellite j relative to the broadcast clock error; v is the residual error, σ 2 is the variance.

[0033] Optionally, based on the calculated pseudorange residuals and satellite-to-ground observation data, the satellite-based augmented differential corrections are calculated, including:

[0034] The least squares method is used to solve equations (4) and (5) to estimate the ephemeris correction ΔO of GNSS satellite j at time t: j (t), clock correction ΔT j (t) and the satellite ephemeris clock correction covariance matrix

[0035]

[0036] [ΔO j (t)ΔT j (t)] T =(G j (t) T H j (t) -1 G j (t)) -1 G j (t) T H j (t) -1 F j (t) (6)

[0037]

[0038] in, M is the number of low-orbit satellites that observe GNSS satellite j at the same time, and N is the number of ground stations that observe GNSS satellite j at the same time.

[0039] Optionally, the satellite-based augmentation integrity parameters calculated based on the calculated satellite-based augmentation differential correction number and the satellite-to-earth observation data include:

[0040] Using the ephemeris correction ΔO j (t) and clock correction ΔT j (t) Corrected pseudo-range observation residuals of LEO satellite and ground station It is expressed as:

[0041]

[0042] Determine the total pseudo-range residuals of GNSS satellite j observed by the low-orbit satellite and the ground station within one update cycle of the satellite-based augmented differential correction The mean and standard deviation The standard deviation is used to characterize the accuracy of the integrity parameter Dual Frequency Range Error (DFRE):

[0043]

[0044] The DFRE of GNSS satellite j is expressed as:

[0045]

[0046] An embodiment of the present application also proposes a satellite-based enhanced integrity monitoring system for joint satellite-Earth observation, including a processor and a memory, wherein a computer program is stored on the memory, and when the computer program is executed by the processor, the steps of the satellite-based enhanced integrity monitoring method for joint satellite-Earth observation as described above are implemented.

[0047] The embodiment of the present application carries a GNSS monitoring receiver on a low-orbit satellite to jointly process the GNSS observation data of the ground monitoring station and the GNSS observation data onboard the low-orbit satellite, thereby achieving continuous satellite-based enhanced integrity monitoring of the entire flight arc of the GNSS satellite.

[0048] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0050] Figure 1 The basic process diagram of the satellite-based enhanced integrity monitoring method for combined satellite-ground observation according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0051] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0052] The present application embodiment provides a satellite-based enhanced integrity monitoring method for joint satellite-ground observation, such as Figure 1 As shown, the following steps are included:

[0053] In step S101, all low-orbit satellite observation data and ground station observation data of the current epoch are obtained. In some embodiments, obtaining all low-orbit satellite observation data and ground station observation data of the current epoch also includes: converting all the low-orbit satellite observation data and ground station observation data of the current epoch obtained into a unified format, and eliminating non-current epoch data and data with an elevation angle less than the altitude cutoff angle.

[0054] In step S102, an ionosphere-free combined observation value is constructed for the low-orbit satellite observation data and the ground station observation data to eliminate the ionosphere delay error. In some embodiments, the ionosphere-free combined observation value is constructed for the low-orbit satellite observation data and the ground station observation data to meet the following conditions:

[0055]

[0056] In the formula, and is the pseudorange and carrier phase observation value of GNSS satellite j observed by low-orbit satellite i after ionosphere-free combination, and P is the pseudorange and carrier phase observation value of GNSS satellite j observed by ground station k after ionospheric-free combination, LEO,i,1 , L LEO,i,1 and P LEO,i,2 , L LEO,i,2 P is the L1 and L5 frequency pseudorange and carrier phase observation value of GNSS satellite j observed by low-orbit satellite i, STA,k,1 , LSTA,k,1 and P STA,k,2 , L STA,k,2 are the pseudoranges and carrier phase observations of the L1 and L5 frequency points observed by ground station k, and f1 and f2 are the frequencies of the L1 and L5 frequency points;

[0057] Based on the constructed ionosphere-free combined observations, the phase winding error, satellite phase center change, earth solid tide correction, ocean load tide correction, earth rotation correction, relativistic effect and other errors are corrected to obtain the corrected low-orbit satellite pseudorange and carrier phase observations. As well as ground station pseudorange and carrier phase observations

[0058] In step S103, the low-orbit satellite orbit and clock error are determined according to the low-orbit satellite and the ground station observation data. Specifically, determining the low-orbit satellite orbit and clock error according to the low-orbit satellite and the ground station observation data includes:

[0059] Based on the coordinate information of ground monitoring station k [x STA,k ,y STA,k ,z STA,k ], all LEO satellite and ground station observation data are processed to determine the orbit and clock error of LEO satellite i:

[0060]

[0061] Where c is the speed of light. Based on formula (2), all observation data at time t are solved and the following parameters are estimated using the least squares method: The orbit O of GNSS satellite j j (t) = [X j (t),Y j (t),Y j (t)] and the clock error δt j (t), the orbit of the low-orbit star i O LEO,i (t) = [x LEO,i (t),y LEO,i (t),z LEO,i (t)] and the clock error δt LEO,i (t), ground station clock error δt STA,k (t), the integer ambiguity of GNSS satellite j observed by low-orbit satellite i The integer ambiguity of GNSS satellite j observed by ground station k

[0062] In step S104, the pseudo-range residuals of the pseudo-range observation data of the low-orbit satellite and the ground station are calculated according to the determined low-orbit satellite orbit and clock error and the known coordinates of the ground station. Specifically, according to the determined low-orbit satellite orbit and clock error, the pseudo-range residuals of the pseudo-range observation data of the low-orbit satellite and the ground station are calculated, including:

[0063] Calculate the ephemeris of satellite j at time t using the ephemeris parameters in the navigation message broadcast by the GNSS satellite Combined with the orbit of low-orbit star i at time t [x LEO,i (t),y LEO,i (t),z LEO,i (t)] and the coordinates of ground station k [x STA,k ,y STA,k ,z STA,k ], calculate the geometric distance between low-orbit satellite i and ground station k and GNSS satellite j at time t and

[0064]

[0065] Calculate the clock error of satellite j at time t using the clock error parameters in the navigation message broadcast by the GNSS satellite

[0066]

[0067] For low-orbit satellite observation data, and δt LEO,i (t)From Eliminate the pseudo-range residual of the low-orbit satellite i observation

[0068]

[0069] For ground station observation data, and δt STA,k (t)From P STA,k (t) is eliminated to obtain the pseudorange residual observed by ground station k

[0070]

[0071] Among them, ΔO j (t) is the correction of the real ephemeris of GNSS satellite j relative to the broadcast ephemeris; is the unit direction vector from LEO satellite i and ground station k to GNSS satellite j; ΔT j (t) is the correction of the true clock error of GNSS satellite j relative to the broadcast clock error; v is the residual error, σ 2 is the variance.

[0072] In step S105, the satellite-based enhanced differential correction is calculated based on the calculated pseudorange residuals and satellite-to-earth observation data.

[0073] Specifically, according to the calculated pseudorange residuals and satellite-to-ground observation data, the satellite-based enhanced differential correction is calculated including:

[0074] The least squares method is used to solve equations (4) and (5) to estimate the ephemeris correction ΔO of GNSS satellite j at time t: j (t), clock correction ΔT j (t) and the satellite ephemeris clock correction covariance matrix

[0075]

[0076]

[0077] in, M is the number of low-orbit satellites that observe GNSS satellite j at the same time, and N is the number of ground stations that observe GNSS satellite j at the same time.

[0078] In step S106, the satellite-based augmentation integrity parameters are calculated based on the calculated satellite-based augmentation differential corrections and the satellite-to-earth observation data.

[0079] Specifically, the satellite-based augmentation integrity parameters calculated based on the calculated satellite-based augmentation differential correction number and the satellite-to-ground observation data include:

[0080] Using the ephemeris correction ΔO j (t) and clock correction ΔT j (t) Corrected pseudo-range observation residuals of LEO satellite and ground station It is expressed as:

[0081]

[0082] Determine the total pseudo-range residuals of GNSS satellite j observed by the low-orbit satellite and the ground station within one update cycle of the satellite-based augmented differential correction The mean and standard deviation The standard deviation is used to characterize the accuracy of the integrity parameter Dual Frequency Range Error (DFRE):

[0083]

[0084] The DFRE of GNSS satellite j is expressed as:

[0085]

[0086] The method of the present application solves the problem that satellite-based enhanced integrity monitoring is restricted by the layout of ground monitoring stations. The method of the present application can perform integrity monitoring on the entire flight arc of the GNSS satellite, and can simultaneously determine the position of low-orbit satellites and monitor the status of low-orbit satellites; the method of the present application is combined with reality and is easy to implement in engineering.

[0087] An embodiment of the present application also proposes a satellite-based enhanced integrity monitoring system for joint satellite-Earth observation, including a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the satellite-based enhanced integrity monitoring method for joint satellite-Earth observation as described above are implemented.

[0088] It should be noted that in the various embodiments of the present application, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0089] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0090] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0091] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A satellite-based enhanced integrity monitoring method for combined satellite-ground observation, characterized in that: include: Obtain all low-orbit satellite observation data and ground station observation data in the current epoch; For low-orbit satellite observation data and ground station observation data, construct ionosphere-free combined observation values ​​to eliminate ionospheric delay errors; Determine the orbit and clock error of the low-orbit satellite based on the observation data of the low-orbit satellite and the ground station; According to the determined LEO satellite orbit and clock error and the known coordinates of the ground station, the pseudorange residuals of the pseudorange observation data of the LEO satellite and the ground station are calculated; Calculate satellite-based enhanced ephemeris and clock differential corrections based on the calculated pseudorange residuals and satellite-to-ground observation data; The satellite-based augmentation integrity parameters are calculated based on the calculated satellite-based augmentation ephemeris and clock differential corrections, as well as the satellite-to-earth observation data.

2. The satellite-based enhanced integrity monitoring method for joint satellite-ground observation according to claim 1, characterized in that: Acquiring all low-orbit satellite observation data and ground station observation data of the current epoch also includes: converting all low-orbit satellite observation data and ground station observation data of the current epoch acquired into a unified format, and eliminating non-current epoch data and data with elevation angles less than the altitude cutoff angle.

3. The satellite-based enhanced integrity monitoring method for joint satellite-ground observation according to claim 1, characterized in that: For low-orbit satellite observation data and ground station observation data, the ionosphere-free combined observation values ​​are constructed to meet the following requirements: In the formula, and is the pseudorange and carrier phase observation value of GNSS satellite j observed by low-orbit satellite i after ionosphere-free combination, and P is the pseudorange and carrier phase observation value of GNSS satellite j observed by ground station k after ionospheric-free combination, LEO,i,1 , L LEO,i,1 and P LEO,i,2 , L LEO,i,2 P is the L1 and L5 frequency pseudorange and carrier phase observation value of GNSS satellite j observed by low-orbit satellite i, STA,k,1 , L STA,k,1 and P STA,k,2 , L STA,k,2 are the pseudoranges and carrier phase observations of the L1 and L5 frequency points observed by ground station k, and f1 and f2 are the frequencies of the L1 and L5 frequency points; Based on the constructed ionosphere-free combined observations, the corrected LEO pseudorange and carrier phase observations are determined As well as ground station pseudorange and carrier phase observations 4. The satellite-based enhanced integrity monitoring method for joint satellite-ground observation according to claim 3, characterized in that: Determining the orbit and clock error of a low-orbit satellite based on the observation data of the low-orbit satellite and the ground station includes: Based on the coordinate information of ground monitoring station k [x STA,k ,y STA,k ,z STA,k ], all LEO satellite and ground station observation data are processed to determine the orbit and clock error of LEO satellite i: Where c is the speed of light. Based on formula (2), all observation data at time t are jointly solved and the following parameters are estimated using the least squares method: The orbit O of GNSS satellite j j (t) = [X j (t),Y j (t),Y j (t)] and the clock error δt j (t), the orbit of the low-orbit star i O LEO,i (t) = [x LEO,i (t),y LEO,i (t),z LEO,i (t)] and the clock error δt LEO,i (t), ground station clock error δt STA,k (t), the integer ambiguity of GNSS satellite j observed by low-orbit satellite i The integer ambiguity of GNSS satellite j observed by ground station k 5. The satellite-based enhanced integrity monitoring method for joint satellite-ground observation according to claim 4, characterized in that: Based on the determined LEO satellite orbit and clock error and the known coordinates of the ground station, the pseudorange residuals of the pseudorange observation data of the LEO satellite and the ground station are calculated, including: Calculate the ephemeris of satellite j at time t using the ephemeris parameters in the navigation message broadcast by the GNSS satellite Combined with the orbit of low-orbit star i at time t [x LEO,i (t),y LEO,i (t),z LEO,i (t)] and the coordinates of ground station k [x STA,k ,y STA,k ,z STA,k ], calculate the geometric distance between low-orbit satellite i and ground station k and GNSS satellite j at time t and Calculate the clock error of satellite j at time t using the clock error parameters in the navigation message broadcast by the GNSS satellite For low-orbit satellite observation data, and δt LEO,i (t)From Eliminate the pseudo-range residual of the low-orbit satellite i observation For ground station observation data, and δt STA,k (t)From P STA,k (t) is eliminated to obtain the pseudorange residual observed by ground station k Among them, ΔO j (t) is the correction of the real ephemeris of GNSS satellite j relative to the broadcast ephemeris; is the unit direction vector from LEO satellite i and ground station k to GNSS satellite j; ΔT j (t) is the correction of the true clock error of GNSS satellite j relative to the broadcast clock error; v is the residual error, σ 2 is the variance.

6. The satellite-based enhanced integrity monitoring method for joint satellite-ground observation according to claim 5, characterized in that: Based on the calculated pseudorange residuals and satellite-to-ground observation data, the satellite-based enhanced ephemeris and clock differential corrections are calculated, including: The least squares method is used to solve equations (4) and (5) to estimate the ephemeris correction ΔO of GNSS satellite j at time t: j (t), clock correction ΔT j (t) and the satellite ephemeris clock correction covariance matrix [ΔO j (t)ΔT j (t)] T =(G j (t) T H j (t) -1 G j (t)) -1 G j (t) T H j (t) -1 F j (t) (6) in, M is the number of low-orbit satellites that observe GNSS satellite j at the same time, and N is the number of ground stations that observe GNSS satellite j at the same time.

7. The satellite-based enhanced integrity monitoring method for joint satellite-ground observation according to claim 6, characterized in that: The satellite-based augmentation integrity parameters calculated based on the calculated satellite-based augmentation differential correction number and the satellite-to-ground observation data include: Using the ephemeris correction ΔO j (t) and clock correction ΔT j (t) Corrected pseudo-range observation residuals of LEO satellite and ground station It is expressed as: Determine the total pseudo-range residuals of GNSS satellite j observed by the low-orbit satellite and the ground station within one update cycle of the satellite-based augmented differential correction The mean and standard deviation The standard deviation is used to characterize the accuracy of the integrity parameter Dual Frequency Range Error (DFRE): The DFRE of GNSS satellite j is expressed as:

8. A satellite-based enhanced integrity monitoring system for joint satellite-ground observation, characterized in that: The method comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the satellite-based enhanced integrity monitoring method for joint satellite-earth observation are implemented as described in any one of claims 1 to 7.

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