INS-assisted dynamic high-precision positioning and attitude determination method and system

Abstract

The invention discloses an INS-assisted dynamic high-precision positioning and attitude determination method and system. According to the method, a continuous observation value of an INS is used for assisting a GNSS to carry out cycle slip detection and integer ambiguity calculation. According to the method, the GNSS carrier phase cycle slip detection efficiency and the integer ambiguity resolving efficiency are greatly improved, the satellite signal recapturing time of the GNSS receiver is shortened, the accumulated error of INS long-time observation is smoothed by using the high-precision performance of the GNSS carrier phase observation value, and the positioning and attitude determination performance of the combined system in a high-dynamic environment is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high-precision positioning technology, and particularly relates to an INS-assisted dynamic high-precision positioning and pose determination method and system, which can be applied to satellite communication, satellite navigation, vehicle-mounted integrated navigation and the like. BACKGROUND

[0002] At present, a single navigation positioning technology is difficult to meet all scene requirements, and satellite navigation GNSS and inertial navigation INS, as two most important basic technologies in the field of location services, have been deeply applied in various industries. Satellite navigation does not diverge with time, has high absolute positioning accuracy, and can provide services all day round. Inertial navigation is not disturbed by the outside world, has high accuracy, and can output all-around information such as position, speed and attitude. Therefore, satellite navigation system GNSS and inertial navigation system INS have natural fusion, and GNSS / INS integrated navigation system can provide three-dimensional position, three-dimensional speed and accurate time information, and becomes an important direction of navigation technology application.

[0003] For dynamic users, the performance of GNSS high-precision positioning can be improved in the form of INS assistance. Traditional INS / GNSS integrated navigation technology mostly adopts fusion processing of pseudorange / pseudorange rate observations of a GNSS receiver and inertial navigation data. This structure is relatively simple to implement, but in a high dynamic environment, the positioning performance and reliability are too dependent on the satellite signal quality of the GNSS receiver, and usually 5 or more satellites need to be observed to solve the floating point solution.

[0004] Traditional INS / GNSS integrated navigation mostly directly takes the position, speed and attitude values of the system as state variables, without fully considering the error propagation in the system, resulting in problems such as increased linearization error, complicated Jacobian matrix calculation, large matrix values causing great memory space consumption, long execution time and low efficiency, which easily causes the system to have increased error or even divergent results. Since GNSS pose determination needs synchronous observation of multiple antennas, as long as one of the antennas has no observation value or has a cycle slip, the accuracy of the related baseline and attitude will be affected. After the navigation signal is recaptured, it usually takes multiple epochs to re-fix the ambiguity. SUMMARY

[0005] The present application uses INS-assisted GNSS cycle slip detection and integer ambiguity resolution to quickly detect cycle slip changes, improve the efficiency of navigation signal recapture, and realize accurate and reliable positioning and pose determination in complex dynamic environments.

[0006] Technical scheme: An INS-assisted dynamic high-precision positioning and pose determination method, comprising using INS-assisted GNSS for cycle slip detection and integer ambiguity resolution.

[0007] The cycle slip detection comprises obtaining carrier phase double-difference integer ambiguity by using baseline length, INS output attitude angle information, INS position information and carrier information; obtaining triple-difference integer ambiguity by differentiating adjacent epochs, the triple-difference integer ambiguity is 0 in the case of no cycle slip, and the absolute value of detection test value is less than detection threshold; if cycle slip is detected, the detection test value is rounded up as cycle slip repair value;

[0008] The integer ambiguity resolution comprises that after multiple antennas are installed on the GNSS carrier, GNSS carrier positioning is completed at the same time of INS initialization to obtain GNSS carrier initial attitude angle and accurate position of each antenna; in dynamic resolution, reference baseline estimation value based on INS and baseline optimal estimation value based on double-difference pseudo-range observation are obtained, the two estimation values are weighted and averaged to obtain weighted and averaged real-time reference baseline value, and the integer ambiguity float solution is solved by combining double-difference carrier phase observation value.

[0009] Further, the cycle slip detection further comprises further verifying the detection result of cycle slip by using ionospheric residual error method under multi-frequency data.

[0010] Further, the process of obtaining the carrier phase double-difference integer ambiguity comprises:

[0011] According to baseline length b AB and the attitude angle information output by the INS, the reference baseline estimation value based on the INS is deduced According to the INS position information, satellite observation direction L1 is obtained, and double-difference station-satellite geometric distance based on INS information is obtained is:

[0012]

[0013] Let According to the satellite i, j observation direction vector obtained according to the INS position information, formula (1) is substituted into the carrier phase observation difference equation, and transformation can obtain:

[0014]

[0015] In the formula, is the carrier phase double-difference integer ambiguity obtained by simultaneously observing satellites i and j by observation station A and observation station B, that is are the integer ambiguities of satellite i observed by observation station A and observation station B respectively, are the integer ambiguities of satellite j observed by observation station A and observation station B respectively; is double-difference carrier phase observation, and λ is the observation carrier wavelength, These are the carrier phase values ​​of satellite i observed by observation station A and observation station B, respectively. These are the carrier phase values ​​of satellite j observed by observation stations A and B, respectively. The carrier phase residual double difference values ​​are obtained by observation station A and observation station B simultaneously observing satellite i and satellite j.

[0016] Furthermore, the process of obtaining the cycle slip repair value includes:

[0017] Differences are performed between adjacent epochs to obtain the three-difference integer ambiguity:

[0018]

[0019] In the absence of cycle slip The detection test value χ is taken as follows:

[0020]

[0021] Let the detection threshold be ζ, then in the case of no cycle slip, the following should be satisfied:

[0022] |χ|<ζ (5)

[0023] If a cycle slip is detected, the χ value is rounded up to obtain the cycle slip repair value △N, which is:

[0024]

[0025] round is the round-up function.

[0026] Furthermore, the ionospheric residual method includes:

[0027] By utilizing triple-difference integer ambiguity and subtracting at different frequencies at the same time, ambiguity can be eliminated. We obtain the four difference equations:

[0028]

[0029] In the formula, λ1 and λ2 are the wavelengths corresponding to the GNSS carrier frequencies f1 and f2, respectively, and the subscripts 1 and 2 represent the values ​​obtained by observation using the f1 and f2 frequency carriers, respectively.

[0030] The following verification values ​​are used to check the repair values ​​△N1 and △N2:

[0031]

[0032] The verification is performed by checking the relationship between different frequencies. In the case of no cycle slip, ν = 0.

[0033] Furthermore, the process of obtaining the initial attitude angle of the GNSS carrier and the precise positions of each antenna includes:

[0034] The vehicle coordinate system is transformed to the navigation coordinate system using three Euler angles, namely, by rotating the heading angle α, pitch angle γ, and roll angle β around the Z-axis, X-axis, and Y-axis respectively. The corresponding rotation matrices are as follows:

[0035]

[0036] The relationship between the antenna's coordinates in the carrier coordinate system b and the navigation coordinate system n is then obtained as follows:

[0037]

[0038] Based on the initial attitude angle att0=(γ0,β0,α0) T The antenna coordinates in the carrier coordinate system can be solved by static positioning of the antenna.

[0039] Furthermore, in the dynamic solution, the real-time attitude angles (att) measured by the INS are used... t =(γ t ,β t ,α t ) T Calculate the real-time reference baseline vector Initial baseline values ​​solved during initialization The real-time reference baseline based on INS is then obtained as follows:

[0040]

[0041] For the above formula Least squares estimation is performed to obtain the optimal baseline estimate based on the double-difference pseudorange observations.

[0042] INS-based reference baseline estimates and Perform a weighted average to obtain the weighted average.

[0043] Time reference baseline value

[0044]

[0045] In the formula, k∈[0,1],w I w ρ They are respectively and The weighting factor; the baseline error variance obtained from INS and GNSS pseudorange measurements is σ. I σ ρ Take weight

[0046] Will Substituting into the carrier phase observation equation, we get:

[0047]

[0048] Based on equations (14) and (15), and combined with the double-difference carrier phase observations, the integer ambiguity floating-point solution can be calculated.

[0049] An INS-assisted dynamic high-precision positioning and attitude determination system, the system comprising a Global Navigation Satellite System (GNSS) and an Inertial Navigation System (INS); the system utilizes INS to assist GNSS in cycle slip detection and integer ambiguity resolution;

[0050] Furthermore, the cycle slip detection includes obtaining carrier phase double-difference integer ambiguity using baseline length, attitude angle information output by INS, INS position information, and carrier information; performing difference between adjacent epochs to obtain triple-difference integer ambiguity; in the absence of cycle slips, the triple-difference integer ambiguity is 0, and the absolute value of the detection test value is less than the detection threshold; if a cycle slip is detected, the detection test value is rounded up as the cycle slip repair value.

[0051] Furthermore, the integer ambiguity resolution includes setting up multiple antennas on the GNSS carrier, completing the GNSS carrier positioning simultaneously with INS initialization, obtaining the initial attitude angle of the GNSS carrier and the precise position of each antenna; in the dynamic resolution, obtaining the reference baseline estimate based on INS and the optimal baseline estimate based on double-difference pseudorange observations, taking a weighted average of the two estimates to obtain the weighted average real-time reference baseline value, and combining the double-difference carrier phase observations to calculate the integer ambiguity floating-point solution.

[0052] Furthermore, the system includes GNSS observation satellite i, GNSS observation satellite j, observation station A, and observation station B.

[0053] Beneficial effects: The method described in this invention, by utilizing INS-assisted GNSS carrier phase observation, can achieve small cycle slip detection and single-epoch ambiguity determination in GNSS satellite signal rejection environments, quickly re-fixing integer ambiguities, and can also fix integer ambiguities even when there are fewer than 5 visible satellites. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of an INS / GNSS combined observation system. Detailed Implementation

[0055] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0056] Example 1:

[0057] An INS-assisted dynamic high-precision positioning and attitude determination method includes using INS-assisted GNSS for cycle slip detection and integer ambiguity resolution;

[0058] The cycle slip detection includes obtaining carrier phase double-difference integer ambiguity using baseline length, attitude angle information output by INS, INS position information, and carrier information; differential calculation is performed between adjacent epochs to obtain triple-difference integer ambiguity; in the absence of cycle slip, the triple-difference integer ambiguity is 0, and the absolute value of the detection test value is less than the detection threshold; if a cycle slip is detected, the detection test value is rounded up as the cycle slip repair value.

[0059] Specifically, for such Figure 1 The INS / GNSS combined observation system, based on the baseline length b AB The reference baseline value can be inferred from the attitude angle information output by the INS. Based on the INS location information, the satellite observation direction L1 is obtained, and the geometric distance between the two differential stations based on INS information is:

[0060]

[0061] remember The observation direction vectors of satellite i and j are obtained from the INS position information. Substituting equation (1) into the carrier phase observation differential equation, we can obtain:

[0062]

[0063] In the formula, To obtain carrier phase double-difference integer ambiguity for observation stations A and B simultaneously observing satellites i and j, i.e. Let be the integer ambiguities of satellite i observed by observation stations A and B, respectively. These are the integer ambiguities of satellite j observed by observation stations A and B, respectively. This is a double-difference carrier phase observation, where λ is the observed carrier wavelength. These are the carrier phase values ​​of satellite i observed by observation station A and observation station B, respectively. These are the carrier phase values ​​of satellite j observed by observation stations A and B, respectively. Observation station A and observation station B simultaneously observe the carrier phase residual double difference values ​​of satellite i and satellite j.

[0064] The process of obtaining the cycle slip repair value includes:

[0065] Differences are performed between adjacent epochs to obtain the three-difference integer ambiguity:

[0066]

[0067] In the absence of cycle slip Therefore, the detection test value χ can be taken as follows:

[0068]

[0069] Let the detection threshold be ζ, then in the case of no cycle slip, the following should be satisfied:

[0070] |χ|<ζ (5)

[0071] If a cycle slip is detected, the cycle slip repair value ΔN can be directly obtained by rounding up χ.

[0072]

[0073] The ionospheric residual method includes:

[0074] Using the three-difference ambiguity equation above, subtraction at different frequencies at the same time can eliminate ambiguity. We obtain the four difference equations:

[0075]

[0076] In the formula, λ1 and λ2 are the wavelengths corresponding to the GNSS carrier frequencies f1 and f2, respectively, and the subscripts 1 and 2 represent the values ​​obtained by observation using the f1 and f2 frequency carriers, respectively.

[0077] The following verification values ​​can be used to check the repair values ​​△N1 and △N2:

[0078]

[0079] By verifying the relationship between different frequencies, ν = 0 in the absence of cycle slips. Through the detection of the INS and carrier phase correlation method and the verification of the ionospheric residual method under double-difference observations, almost all cycle slips can be eliminated.

[0080] The integer ambiguity resolution includes setting up multiple antennas on the carrier and completing static GNSS positioning simultaneously with inertial navigation initialization to obtain the initial attitude angle of the carrier and the precise position of each antenna; in dynamic resolution, the real-time reference baseline estimate based on INS and the reference baseline estimate based on double-difference pseudorange observations are obtained, and the two estimates are weighted and averaged to obtain the weighted average real-time reference baseline value. Combined with the double-difference carrier phase observations, the integer ambiguity floating-point solution is calculated.

[0081] Specifically, since GNSS attitude determination requires simultaneous observations from multiple antennas, if any one antenna fails to provide an observation or experiences a cycle slip, the accuracy of the relevant baseline and attitude will be affected. After the navigation signal is reacquired, multiple epochs are typically required to re-fix the ambiguities. If the ambiguities can be determined in a single epoch, it can avoid the problems of cycle slip detection errors or inaccurate repairs, and also quickly determine the ambiguities after signal reacquisition. Therefore, this invention proposes an inertial navigation-assisted ambiguity resolution method, which uses inertial navigation information to assist in resolving the floating-point ambiguity solution, resulting in a more accurate and stable GNSS attitude after fixing the ambiguities.

[0082] In conventional double-difference relative positioning, the baseline vector b and the ambiguity N are unknown. If the baseline estimate b can be obtained using INS information, then theoretically, the double-difference integer ambiguity floating-point solution N can be calculated using only single-epoch data.

[0083] According to the double-difference observation equation, solving for integer ambiguity floating-point solutions in a single epoch requires obtaining the reference baseline vector, i.e., the reference baseline attitude and reference baseline length. For attitude determination requirements of multi-antenna GNSS carriers, the antennas are often fixed to the carrier, so the baseline lengths and angles between antennas are known. The inertial navigation system (INS) can provide the carrier's reference attitude information, but a certain transformation process is required between it and the baseline attitude, i.e., the installation angles of the INS and antennas, and the transformation between the carrier coordinate system and the navigation coordinate system.

[0084] After multiple antennas are mounted on the carrier, static GNSS positioning is completed simultaneously with inertial navigation initialization, and the initial attitude angles of the carrier (i.e., heading angle α0, roll angle β0 and pitch angle γ0) and the precise positions of each antenna are finally obtained.

[0085] The vehicle coordinate system can be transformed to the navigation coordinate system using three Euler angles, namely, by rotating the heading angle α, pitch angle γ, and roll angle β around the Z-axis, X-axis, and Y-axis respectively. The corresponding rotation matrices are as follows:

[0086]

[0087] The relationship between the antenna's coordinates in the carrier coordinate system b and the navigation coordinate system n is then obtained as follows:

[0088]

[0089] Based on the initial attitude angle att0=(γ0,β0,α0) T The antenna coordinates in the carrier coordinate system can be solved by static positioning of the antenna.

[0090] In dynamic calculation, the real-time attitude angles (att) measured by the INS are used. t =(γ t ,β t ,α t )T Calculate the real-time reference baseline vector Initial baseline values ​​solved during initialization The real-time reference baseline based on INS is then obtained as follows:

[0091]

[0092] For the above formula Least squares estimation is performed to obtain the optimal baseline estimate based on the double-difference pseudorange observations.

[0093] INS-based reference baseline estimates and Perform a weighted average to obtain the weighted average.

[0094] Time reference baseline value

[0095]

[0096] In the formula, k∈[0,1],w I w ρ They are respectively and The weighting factor; the baseline error variance obtained from INS and GNSS pseudorange measurements is σ. I σ ρ Take weight

[0097] Will Substituting into the carrier phase observation equation, we get:

[0098]

[0099] Based on equations (14) and (15), and combined with the double-difference carrier phase observations, the integer ambiguity floating-point solution can be calculated.

[0100] The impact of INS attitude error on the detection results is analyzed below. Taking a detection threshold ζ of 4 times the mean error as an example, to detect small cycle slips within one cycle, the following conditions must be met:

[0101] 4σ X <1 (16)

[0102] That is, the following conditions must be met:

[0103]

[0104] Considering that the carrier wavelengths of the commonly used GPS L1 and L2 frequencies are 19.02 cm and 24.42 cm respectively, taking the GPS L1 frequency as an example, λ = 19.02 cm, we have:

[0105]

[0106] Let the baseline error vector be b. err The baseline true value is b AB That is,

[0107]

[0108] Substituting into equation (18), we get:

[0109]

[0110] In the formula, ξ j For carrier phase measurement noise, considering the high accuracy of carrier phase measurement, it can be ignored, and we have:

[0111]

[0112] Let α be the angle difference between the true baseline value and the measured value. err (in radians), since the angle is very small, the approximate relationship is as follows:

[0113] ||△b err ||=b AB ·|α err | (22)

[0114] Under the following conditions, it is entirely possible to detect a cycle slip of one cycle:

[0115] ||△b err ||=b AB ·|α err |<0.024 (23)

[0116] Taking a baseline of 2m as an example, the following requirements apply to the attitude angle error (in radians):

[0117] |α err |<0.012 (24)

[0118] That is, in a scenario with a baseline of 2m, when the attitude angle error is within 0.012 radians (0.075°), a cycle slip of less than 1 cycle can be detected.

[0119] Furthermore, as can be seen from equation (15), the floating-point solution for this ambiguity is obtained using only observation data from one epoch, providing the necessary conditions for subsequent single-epoch fixed ambiguity. In addition, general double-difference positioning requires at least five observation satellites to obtain a floating-point solution, while the floating-point solution obtained by the method described in this invention does not require a certain number of satellites. Therefore, a fixed solution can be obtained even when the number of visible satellites is extremely small, which also provides strong support for single-epoch fixed ambiguity.

[0120] Example 2:

[0121] An INS-assisted dynamic high-precision positioning and attitude determination system, the system comprising a Global Navigation Satellite System (GNSS) and an Inertial Navigation System (INS); the system utilizes INS to assist GNSS in cycle slip detection and integer ambiguity resolution;

[0122] Furthermore, the cycle slip detection includes obtaining carrier phase double-difference integer ambiguity using baseline length, attitude angle information output by INS, INS position information, and carrier information; performing difference between adjacent epochs to obtain triple-difference integer ambiguity; in the absence of cycle slips, the triple-difference integer ambiguity is 0, and the absolute value of the detection test value is less than the detection threshold; if a cycle slip is detected, the detection test value is rounded up as the cycle slip repair value.

[0123] Furthermore, the integer ambiguity resolution includes setting up multiple antennas on the GNSS carrier, completing the GNSS carrier positioning simultaneously with INS initialization, obtaining the initial attitude angle of the GNSS carrier and the precise position of each antenna; in the dynamic resolution, obtaining the reference baseline estimate based on INS and the optimal baseline estimate based on double-difference pseudorange observations, taking a weighted average of the two estimates to obtain the weighted average real-time reference baseline value, and combining the double-difference carrier phase observations to calculate the integer ambiguity floating-point solution.

[0124] Furthermore, the system includes GNSS observation satellite i, GNSS observation satellite j, observation station A, and observation station B.

Claims

1. An INS-assisted dynamic high-precision positioning and attitude determination method, characterized in that, This includes using INS-assisted GNSS for cycle slip detection and integer ambiguity resolution; The cycle slip detection includes obtaining carrier phase double-difference integer ambiguity using baseline length, attitude angle information output by INS, INS position information and carrier information; differential calculation is performed between adjacent epochs to obtain triple-difference integer ambiguity. In the absence of cycle slip, the triple-difference integer ambiguity is 0 and the absolute value of the detection test value is less than the detection threshold. If a cycle slip is detected, the detection test value is rounded up as the cycle slip repair value; The integer ambiguity resolution includes setting up multiple antennas on the GNSS carrier, completing the GNSS carrier positioning simultaneously with INS initialization, obtaining the initial attitude angle of the GNSS carrier and the precise position of each antenna; in the dynamic resolution, obtaining the reference baseline estimate based on INS and the optimal baseline estimate based on double-difference pseudorange observations, and taking a weighted average of the two estimates to obtain the weighted average real-time reference baseline value, and combining it with the double-difference carrier phase observations to calculate the integer ambiguity floating-point solution.

2. The INS-assisted dynamic high-precision positioning and attitude determination method according to claim 1, characterized in that, The cycle slip detection also includes further verifying the cycle slip detection results using the ionospheric residual method under multi-frequency data.

3. The INS-assisted dynamic high-precision positioning and attitude determination method according to claim 1, characterized in that, The process of obtaining the carrier phase double-difference integer ambiguity includes: Based on baseline length b AB Using the attitude angle information output by the INS, the reference baseline estimate based on the INS is inferred. The satellite observation direction L1 is obtained based on the INS location information, and the geometric distance between the two differential stations based on the INS information is obtained. for: remember The observation direction vectors of satellite i and j are obtained from the INS position information. Substituting equation (1) into the carrier phase observation differential equation, we can obtain: In the formula, To obtain carrier phase double-difference integer ambiguity for observation stations A and B simultaneously observing satellites i and j, i.e. Let be the integer ambiguities of satellite i observed by observation stations A and B, respectively. These are the integer ambiguities of satellite j observed by observation stations A and B, respectively. This is a double-difference carrier phase observation, where λ is the observed carrier wavelength. These are the carrier phase values ​​of satellite i observed by observation station A and observation station B, respectively. These are the carrier phase values ​​of satellite j observed by observation stations A and B, respectively. The carrier phase residual double difference values ​​are obtained by observation station A and observation station B simultaneously observing satellite i and satellite j.

4. The INS-assisted dynamic high-precision positioning and attitude determination method according to claim 1, characterized in that, The process of obtaining the cycle slip repair value includes: Differences are performed between adjacent epochs to obtain the three-difference integer ambiguity: In the absence of cycle slip The detection test value χ is taken as follows: Let the detection threshold be ζ, then in the case of no cycle slip, the following should be satisfied: |χ|<ζ (5) If a cycle slip is detected, the χ value is rounded up to obtain the cycle slip repair value △N, which is: round is the round-up function.

5. The INS-assisted dynamic high-precision positioning and attitude determination method according to claim 2, characterized in that, The ionospheric residual method includes: By utilizing triple-difference integer ambiguity and subtracting at different frequencies at the same time, ambiguity can be eliminated. We obtain the four difference equations: In the formula, λ1 and λ2 are the wavelengths corresponding to the GNSS carrier frequencies f1 and f2, respectively, and the subscripts 1 and 2 represent the values ​​obtained by observation using the f1 and f2 frequency carriers, respectively. The following verification values ​​are used to check the repair values ​​△N1 and △N2: The verification is performed by checking the relationship between different frequencies. In the case of no cycle slip, ν = 0.

6. The INS-assisted dynamic high-precision positioning and attitude determination method according to claim 1, characterized in that, The process of obtaining the initial attitude angle of the GNSS carrier and the precise positions of each antenna includes: The vehicle coordinate system is transformed to the navigation coordinate system using three Euler angles, namely, by rotating the heading angle α, pitch angle γ, and roll angle β around the Z-axis, X-axis, and Y-axis respectively. The corresponding rotation matrices are as follows: The relationship between the antenna's coordinates in the carrier coordinate system b and the navigation coordinate system n is then obtained as follows: Based on the initial attitude angle att0=(γ0,β0,α0) T The antenna coordinates in the carrier coordinate system can be solved by static positioning of the antenna.

7. The INS-assisted dynamic high-precision positioning and attitude determination method according to claim 1, characterized in that, In dynamic calculation, the real-time attitude angles (att) measured by the INS are used. t =(γ) t ,β t ,α t ) T Calculate the real-time reference baseline vector Initial baseline values ​​solved during initialization The real-time reference baseline based on INS is then obtained as follows: For the above formula Least squares estimation is performed to obtain the optimal baseline estimate based on the double-difference pseudorange observations. INS-based reference baseline estimates and The weighted average is used to obtain the real-time reference baseline value. In the formula, w I w ρ They are respectively and The weighting factor; the baseline error variance obtained from INS and GNSS pseudorange measurements is σ. I σ ρ Take weight Will Substituting into the carrier phase observation equation, we get: Based on equations (14) and (15), and combined with the double-difference carrier phase observations, the integer ambiguity floating-point solution can be calculated.

8. An INS-assisted dynamic high-precision positioning and attitude determination system, characterized in that, The system includes a Global Navigation Satellite System (GNSS) and an Inertial Navigation System (INS); the system utilizes INS to assist GNSS in cycle slip detection and integer ambiguity resolution. The cycle slip detection includes obtaining carrier phase double-difference integer ambiguity using baseline length, attitude angle information output by INS, INS position information and carrier information; differential calculation is performed between adjacent epochs to obtain triple-difference integer ambiguity. In the absence of cycle slip, the triple-difference integer ambiguity is 0 and the absolute value of the detection test value is less than the detection threshold. If a cycle slip is detected, the detection test value is rounded up as the cycle slip repair value; The integer ambiguity resolution includes setting up multiple antennas on the GNSS carrier, completing the GNSS carrier positioning simultaneously with INS initialization, obtaining the initial attitude angle of the GNSS carrier and the precise position of each antenna; in the dynamic resolution, obtaining the reference baseline estimate based on INS and the optimal baseline estimate based on double-difference pseudorange observations, and taking a weighted average of the two estimates to obtain the weighted average real-time reference baseline value, and combining it with the double-difference carrier phase observations to calculate the integer ambiguity floating-point solution.

9. The INS-assisted dynamic high-precision positioning and attitude determination system according to claim 8, characterized in that, The system includes GNSS observation satellite i, GNSS observation satellite j, observation station A, and observation station B.

10. An INS-assisted dynamic high-precision positioning and attitude determination system according to claim 8, characterized in that, In dynamic calculation, the real-time attitude angles (att) measured by the INS are used. t =(γ) t ,β t ,α t ) T Calculate the real-time reference baseline vector Initial baseline values ​​solved during initialization The real-time reference baseline based on INS is then obtained as follows: For the above formula Least squares estimation is performed to obtain the optimal baseline estimate based on the double-difference pseudorange observations. INS-based reference baseline estimates and The weighted average is used to obtain the real-time reference baseline value. In the formula, w I w ρ They are respectively and The weighting factor; the baseline error variance obtained from INS and GNSS pseudorange measurements is σ. I σ ρ Take weight Will Substituting into the carrier phase observation equation, we get: By combining the double-difference carrier phase observations, the integer ambiguity floating-point solution can be calculated.

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