Combined navigation positioning method, device and system based on asynchronous differential positioning technology

Abstract

The present invention discloses a combined navigation positioning method, device, and system based on asynchronous differential positioning technology, wherein the method includes: using asynchronous RTK technology, performing double difference processing based on the observation data received at the current moment of the user end and the observation data received at the historical moment of the base station to obtain double difference observation values; calculating the user end INS navigation positioning result and the asynchronous predicted double difference distance based on the received INS data; calculating new information based on the double difference observation value and the predicted double difference distance, and performing Kalman filter estimation to compensate the user end INS navigation positioning result to obtain the user end asynchronous RTK and INS combined navigation positioning result. The use of asynchronous differential positioning technology avoids the problem of synchronous differential inaccuracy caused by data link transmission delay; repeatedly using historical moment data can achieve higher frequency differential result output. It can continuously and stably output higher precision and higher frequency combined navigation positioning results.

Description

Technical Field

[0001] The present invention relates to the field of navigation and positioning technology, and in particular to a combined navigation and positioning method, device and system based on asynchronous differential positioning technology. Background Art

[0002] With the rapid development of autonomous driving technology and advanced vehicle control and safety systems in urban environments, the transportation industry is placing increasingly high demands on navigation accuracy, continuity, and availability. Real-time kinematic (RTK) is a precise positioning technology that utilizes double-difference carrier phase measurements of Global Navigation Satellite System (GNSS) signals. This double-difference technique can remove highly spatially and temporally correlated error terms, achieving centimeter-level positioning accuracy under good observation conditions. However, satellite signals are susceptible to interference and even interruption in urban and canyon areas, resulting in inaccurate or even ineffective positioning. Therefore, land vehicles typically employ RTK / INS integrated navigation to address these issues. For example, Chinese patent publication number CN114966792A discloses a method, device, and system for tightly integrated GNSS+RTK and INS navigation and positioning. Thanks to the strong autonomy, weather resistance, and lack of radio interference of inertial navigation systems (INS), RTK / INS integrated navigation systems can still output navigation and positioning results with an error within a certain range even when satellite signal quality is poor.

[0003] However, traditional RTK systems widely utilize synchronous differential technology, where the base station transmits its observations and station coordinates to the user (mobile station) via a data link. While receiving data from the base station via the data link, the user also collects GNSS observations and combines them into differential observations within the system for real-time processing, resulting in centimeter-level positioning results. This traditional synchronous differential technology requires the user to obtain simultaneous data from both the satellite and the base station. However, data from the base station receiver must be transmitted to the user via a wireless data link. This inevitably introduces data link transmission time delays (DLTTDs), failing to meet the "synchronization" requirements of traditional RTK. This introduces errors in the carrier phase differential of traditional RTK, impacting positioning accuracy. Furthermore, the low update frequency of synchronous differential technology results in a low update frequency for RTK / INS integrated navigation measurements, which in turn affects the accuracy and reliability of integrated navigation. Summary of the Invention

[0004] In response to the above-mentioned shortcomings in the existing technology, the present invention provides a combined navigation positioning method, device and system based on asynchronous differential positioning technology, which adopts asynchronous RTK technology in combination with INS for navigation positioning, and can solve the problems of positioning solution error and low navigation result output frequency caused by data link transmission delay (DLTTD) of existing synchronous RTK technology, and can improve the RTK / INS combined navigation positioning accuracy to a certain extent.

[0005] In a first aspect, a combined navigation and positioning method based on asynchronous differential positioning technology is provided, comprising:

[0006] S1: Using asynchronous RTK technology, double-difference processing is performed based on the observation data received by the user at the current time and the observation data received by the base station at the historical time to obtain double-difference observation values;

[0007] S2: Calculate the asynchronous predicted double difference distance and the user-side INS navigation positioning result based on the received INS data;

[0008] S3: New information is calculated based on the double-difference observation value and the predicted double-difference distance, and Kalman filter estimation is performed to compensate the user-side INS navigation positioning result to obtain the user-side asynchronous RTK and INS combined navigation positioning result.

[0009] Furthermore, the step S1 specifically includes:

[0010] Obtain the observation data of satellite i and satellite j received by the base station at the historical moment;

[0011] Obtain the observation data of satellite i and satellite j received by the user end at the current moment;

[0012] The observation data of satellite i received by the user terminal at the current time is subtracted from the observation data of satellite i received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value of the corresponding satellite i; the observation data of satellite j received by the user terminal at the current time is subtracted from the observation data of satellite j received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value of the corresponding satellite j;

[0013] The asynchronous double-difference observation value is obtained by subtracting the asynchronous inter-station single-difference observation value corresponding to satellite i from the asynchronous inter-station single-difference observation value corresponding to satellite j.

[0014] Furthermore, the double-difference observation value includes a double-difference phase and a double-difference pseudorange.

[0015] Furthermore, the step S2 specifically includes:

[0016] According to the INS data received at the current moment, the user-side INS navigation positioning result is obtained;

[0017] Calculate the distance between the user terminal and satellite i and satellite j at the current moment;

[0018] Calculate the distances between the reference station and satellite i and satellite j at the historical moment;

[0019] Subtract the distance between the user terminal and satellite i at the current moment from the distance between the reference station and satellite i at the historical moment to obtain the asynchronous prediction station single difference value corresponding to satellite i; subtract the distance between the user terminal and satellite j at the current moment from the distance between the reference station and satellite j at the historical moment to obtain the asynchronous prediction station single difference value corresponding to satellite j;

[0020] The single difference between the asynchronous prediction stations corresponding to satellite i and the single difference between the asynchronous prediction stations corresponding to satellite j are subtracted, and the predicted double difference distance based on asynchronous prediction is obtained according to the calculated difference.

[0021] Furthermore, the asynchronous prediction double difference distance It is expressed as follows:

[0022]

[0023] in, It represents the difference between the single difference between the asynchronous prediction station and the corresponding satellite j, t0 represents the historical time, and t1 represents the current time; and denote the unit vectors from the user terminal to satellite i and satellite j respectively; represents the position error vector in the Earth-centered Earth-fixed coordinate system.

[0024] Furthermore, the step S3 specifically includes:

[0025] New information is calculated based on the double difference observation value and the predicted double difference distance;

[0026] Kalman filter estimation is performed based on the new information, and the user-side INS navigation positioning result is compensated according to the estimation result to obtain the user-side asynchronous RTK and INS combined navigation positioning result.

[0027] Furthermore, the new information is expressed as follows:

[0028]

[0029] in, represents the predicted double difference distance, They represent the double-difference pseudorange and double-difference phase in the double-difference observations respectively.

[0030] The Kalman filter state vector is expressed as follows:

[0031]

[0032] Among them, δ is a symbol representing the error state, δr, δv and ψ represent position, velocity and attitude errors respectively, b g and b a Denote the bias errors of the gyroscope and accelerometer, s g and s a denote the scale factor errors of the gyroscope and accelerometer respectively, represents the double-difference ambiguity.

[0033] In a second aspect, a combined navigation and positioning device based on asynchronous differential positioning technology is provided, comprising:

[0034] The double-difference observation value acquisition module is used to obtain double-difference observation values ​​by using asynchronous RTK technology and performing double-difference processing based on the observation data received at the user end at the current time and the observation data received at the reference station at the historical time;

[0035] The predicted double-difference distance acquisition module is used to calculate the asynchronous predicted double-difference distance and the user-side INS navigation positioning result based on the received INS data;

[0036] The integrated navigation module is used to calculate the new information based on the double-difference observation value and the predicted double-difference distance, and perform Kalman filter estimation to compensate the user-side INS navigation positioning result to obtain the user-side asynchronous RTK and INS integrated navigation positioning result.

[0037] Furthermore, the double-difference observation value acquisition module is configured to perform the following steps:

[0038] Obtain the observation data of satellite i and satellite j received by the base station at the historical moment;

[0039] Obtain the observation data of satellite i and satellite j received by the user end at the current moment;

[0040] The observation data of satellite i received by the user terminal at the current time is subtracted from the observation data of satellite i received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value of the corresponding satellite i; the observation data of satellite j received by the user terminal at the current time is subtracted from the observation data of satellite j received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value of the corresponding satellite j;

[0041] The asynchronous double-difference observation value is obtained by subtracting the asynchronous inter-station single-difference observation value corresponding to satellite i from the asynchronous inter-station single-difference observation value corresponding to satellite j.

[0042] Furthermore, the predicted double-difference distance acquisition module is configured to perform the following steps:

[0043] According to the INS data received at the current moment, the user-side INS navigation positioning result is obtained;

[0044] Calculate the distance between the user terminal and satellite i and satellite j at the current moment;

[0045] Calculate the distances between the reference station and satellite i and satellite j at the historical moment;

[0046] Subtract the distance between the user terminal and satellite i at the current moment from the distance between the reference station and satellite i at the historical moment to obtain the asynchronous prediction station single difference value corresponding to satellite i; subtract the distance between the user terminal and satellite j at the current moment from the distance between the reference station and satellite j at the historical moment to obtain the asynchronous prediction station single difference value corresponding to satellite j;

[0047] The single difference between the asynchronous prediction stations corresponding to satellite i and the single difference between the asynchronous prediction stations corresponding to satellite j are subtracted, and the predicted double difference distance based on asynchronous prediction is obtained according to the calculated difference.

[0048] Furthermore, the combined navigation module is configured to perform the following steps:

[0049] New information is calculated based on the double difference observation value and the predicted double difference distance;

[0050] Kalman filter estimation is performed based on the new information, and the user-side INS navigation positioning result is compensated according to the estimation result to obtain the user-side asynchronous RTK and INS combined navigation positioning result.

[0051] In the third aspect, a combined navigation and positioning system based on asynchronous differential positioning technology is provided, including an RTK module, an INS module and a navigation and positioning module;

[0052] The RTK module is used to transmit the observation data received by itself and the observation data sent by the reference station to the navigation and positioning module;

[0053] The INS module is used to transmit the received INS data to the navigation and positioning module;

[0054] The navigation and positioning module is used to execute the steps of the combined navigation and positioning method based on the asynchronous differential positioning technology as described above.

[0055] The present invention proposes a combined navigation positioning method, device, and system based on asynchronous differential positioning technology. This technology uses asynchronous differential positioning technology to perform differential processing using the historical data of the base station and the instantaneous data of the user, thus avoiding the problem of synchronous differential inaccuracy caused by the data link transmission delay of traditional synchronous RTK technology. At the same time, during the intervals between base station data reception, asynchronous RTK technology uses the method of repeatedly utilizing historical moment data to achieve a higher frequency of differential result output. By combining this method with INS for combined navigation positioning, it is possible to continuously and stably output combined navigation positioning results that are smoother, more accurate, and more frequent than those of traditional synchronous RTK / INS combined navigation systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0057] Figure 1 This is a flow chart of a combined navigation and positioning method based on asynchronous differential positioning technology provided by an embodiment of the present invention;

[0058] Figure 2 1 is a comparison diagram of the single difference between synchronous stations and the single difference between asynchronous stations provided by an embodiment of the present invention, wherein (a) is the single difference between synchronous stations, and (b) is the single difference between asynchronous stations. DETAILED DESCRIPTION

[0059] To make the objectives, technical solutions, and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without inventive effort are within the scope of protection of the present invention.

[0060] like Figure 1 As shown, an embodiment of the present invention provides a combined navigation and positioning method based on asynchronous differential positioning technology, including:

[0061] S1: Using asynchronous RTK technology, double-difference processing is performed based on the observation data currently received by the user terminal (corresponding to the mobile station in the figure) and the observation data received at the historical time by the base station to obtain double-difference observation values. Specifically, it includes:

[0062] S11: Obtain the observation data of satellite i and satellite j received by the base station at the historical moment;

[0063] S12: Obtain the observation data of satellite i and satellite j received by the user terminal at the current moment;

[0064] S13: Subtract the observation data of satellite i currently received by the user terminal from the observation data of satellite i received by the reference station at a historical time to obtain a non-synchronous inter-station single-difference observation value corresponding to satellite i; subtract the observation data of satellite j currently received by the user terminal from the observation data of satellite j received by the reference station at a historical time to obtain a non-synchronous inter-station single-difference observation value corresponding to satellite j;

[0065] S14: Subtract the asynchronous inter-station single-difference observation value corresponding to satellite i from the asynchronous inter-station single-difference observation value corresponding to satellite j to obtain an asynchronous double-difference observation value, where the double-difference observation value includes a double-difference phase and a double-difference pseudorange.

[0066] It should be noted that, in specific implementation, the observation data received at the historical moment of the base station is preferably the observation data received by the user terminal at the previous epoch of the base station, that is, during the interval between the observation data of the two epochs before and after the base station, the user terminal reuses the observation data of the previous epoch for double difference processing.

[0067] S2: Calculate the asynchronous predicted double difference distance and the user-side INS navigation positioning result based on the received INS data. Specifically including:

[0068] S21: Based on the INS data received at the current moment (including the measurements of the accelerometer and gyroscope), the INS navigation and positioning result of the user terminal is calculated. The navigation and positioning result includes the position, velocity and attitude of the user terminal, which can be calculated by the INS mechanical arrangement algorithm;

[0069] S22: Calculate the distances between the user terminal and satellite i and satellite j at the current moment. During the calculation, the position of the satellite at the corresponding moment is calculated based on the broadcast ephemeris.

[0070] S23: Calculate the distances between the reference station and satellite i and satellite j at the historical moment;

[0071] S24: Subtract the distance between the user terminal and satellite i at the current moment from the distance between the reference station and satellite i at the historical moment to obtain a non-synchronous prediction station-to-station single difference value corresponding to satellite i; subtract the distance between the user terminal and satellite j at the current moment from the distance between the reference station and satellite j at the historical moment to obtain a non-synchronous prediction station-to-station single difference value corresponding to satellite j;

[0072] S25: Subtract the asynchronous prediction inter-station single difference value corresponding to satellite i from the asynchronous prediction inter-station single difference value corresponding to satellite j, and obtain the asynchronous prediction double difference distance based on the calculated difference value.

[0073] S3: Calculate the new information based on the double-difference observation value and the predicted double-difference distance, perform Kalman filter estimation, and compensate the user-side INS navigation positioning result to obtain the user-side asynchronous RTK and INS combined navigation positioning result. Specifically including:

[0074] S31: Calculate new information based on double-difference observations and predicted double-difference distances;

[0075] S32: Perform Kalman filter estimation based on the new information, and compensate the user-side INS navigation positioning result based on the estimation result (including errors in position, velocity, and attitude) to obtain the user-side asynchronous RTK and INS combined navigation positioning result.

[0076] The combined navigation and positioning method based on asynchronous differential positioning technology provided in the above embodiment adopts asynchronous differential positioning technology and uses the historical data of the reference station and the instantaneous data of the user for differential processing, thereby avoiding the synchronous differential inaccuracy caused by the data link transmission delay of the traditional synchronous RTK technology. At the same time, due to objective reasons, the frequency of the reference station receiving data is limited and relatively low, but the frequency of the user end (mobile station) receiving data can be significantly higher than the frequency of the reference station receiving data. The traditional synchronous RTK technology requires data synchronization, resulting in the overall data update frequency being based on the reference station design, resulting in a low data update frequency. In the embodiment of the present invention, during the interval between the reference station receiving data, the asynchronous RTK technology adopts a method of repeatedly utilizing historical moment data. Therefore, the frequency of the user end receiving data can be set to be greater than the frequency of the reference station receiving data. The overall data update is based on the frequency of the user end receiving data, which can achieve a higher frequency differential result output. By combining this method with INS for combined navigation and positioning, it is possible to continuously and stably output a combined navigation and positioning result that is smoother, more accurate, and more frequent than the traditional synchronous RTK / INS combined navigation system.

[0077] To further understand asynchronous RTK technology, the following is a further explanation of the specific derivation process of the double-difference phase observation equation.

[0078] Comparison of the single-difference principle between asynchronous RTK and traditional synchronous RTK Figure 2 As shown. Traditional synchronous RTK technology requires the user end (mobile station) receiver to simultaneously receive the observation data of satellite i obtained by the base station at time t0 and the observation data of satellite i obtained by the user end itself, and to make a difference between the two to obtain the inter-station single difference value for satellite i, as shown Figure 2(a) is shown. Similarly, the same method is used to obtain the inter-station single difference for satellite j, and the two single differences are subtracted to obtain the synchronous RTK double difference observation value. Asynchronous RTK allows the existence of time difference in the inter-station single difference. The inter-station single difference is obtained by subtracting the observation data of satellite i at the user end at time t1 and the observation data of satellite i at the base station at time t0, as shown in Figure 2 As shown in (b); and in the same way, the inter-station single difference value for satellite j is obtained, and the two single differences are subtracted to obtain the asynchronous RTK double difference observation value.

[0079] The undifferenced phase observation equations of the reference station A and the user terminal B for satellite i at time t0 and t1 are as follows:

[0080]

[0081]

[0082] Where λ is the wavelength of the satellite signal, φ is the carrier phase measurement value, ρ is the geometric distance between the satellite and the receiver, C is the speed of light, and dt A represents the receiver clock error of reference station A, dt i represents the clock error of satellite i, N is the whole-cycle ambiguity, and Respectively represent the ionospheric and tropospheric delays between reference station A and satellite i, E represents the ephemeris error, ε represents the random error of carrier phase measurement, t0 and T0 represent the time when the reference station receiver receives the signal and the time when the corresponding satellite transmits the signal, t1 and T1 represent the time when the user terminal receiver receives the signal and the time when the corresponding satellite transmits the signal, subscripts A and B represent the reference station and the user terminal, respectively, and superscript i represents satellite i. Subtracting the two equations yields the inter-station single-difference phase observation equation:

[0083]

[0084] Where,

[0085] Similar to synchronous RTK, the inter-station single difference of asynchronous RTK weakens the influence of ionospheric and tropospheric delays.

[0086] Similarly, the inter-station single-difference phase observation equation for satellite j can be obtained according to the same method as above:

[0087]

[0088] Subtracting the single-difference observation equations between the two stations, we obtain the following double-difference phase observation equations for asynchronous RTK satellite stations:

[0089]

[0090] in, By analogy, we can get The calculation formula of is not described here one by one, where represents the double-difference ambiguity.

[0091] As can be seen, the double-difference result eliminates the receiver clock error. When the time difference δt = t1 - t0 (i.e., the data link transmission delay DLTTD) is very short and the baseline is short (the distance between the two receivers is ≤ 10 km), the spatial and temporal variations of the ionospheric and tropospheric delays, as well as the ephemeris error, can be ignored. Therefore, the double-difference phase observation equation for the asynchronous RTK satellite station, ignoring the related errors, is obtained as follows:

[0092]

[0093] The satellite clock error is generally expressed using a second-order polynomial model with broadcast ephemeris parameters. The specific expression method is as follows:

[0094]

[0095] in is the calibration coefficient, and toc is the satellite reference time. It is usually 0. In the case of short baseline, the influence of relativity on the satellite clock is ignored, and the final double-difference phase observation equation of the asynchronous RTK station is obtained:

[0096]

[0097] Similarly, using the same method and ignoring the related errors, the double-difference pseudo-range observation equation of the asynchronous RTK satellite station can be obtained:

[0098]

[0099] At this point, the double difference phase is obtained through the asynchronous RTK satellite station double difference phase observation equation and the satellite station double difference pseudorange observation equation. and double-difference pseudorange

[0100] The predicted double difference distance based on asynchronous calculation is obtained based on INS data It can be expressed as follows:

[0101]

[0102] in, and denote the unit vectors from the user terminal to satellite i and satellite j respectively; represents the position error vector in the Earth-centered Earth-fixed coordinate system.

[0103] Therefore, the innovation can be expressed as follows:

[0104]

[0105] in, represents the predicted double difference distance, They represent the double-difference pseudorange and double-difference phase in the double-difference observations respectively.

[0106] The Kalman filter (Kalman wave) of the integrated navigation of asynchronous RTK and INS takes the double difference ambiguity as the state quantity. The complete Kalman filter state vector is expressed as follows:

[0107]

[0108] Among them, δ is a symbol representing the error state, δr, δv and ψ represent position, velocity and attitude errors respectively, b g and b a Denote the bias errors of the gyroscope and accelerometer, s g and s a denote the scale factor errors of the gyroscope and accelerometer respectively, represents the double-difference ambiguity.

[0109] Therefore, based on the new information, the errors in the user-side position, velocity, and attitude estimated by Kalman filtering are used to compensate the navigation and positioning results of the INS user side. The zero bias errors and scale factor errors of the gyroscope and accelerometer obtained are fed back to the INS as sensor errors for sensor calibration.

[0110] The embodiment of the present invention further provides a combined navigation and positioning device based on asynchronous differential positioning technology, comprising:

[0111] The double-difference observation value acquisition module is used to obtain double-difference observation values ​​by using asynchronous RTK technology and performing double-difference processing based on the observation data received at the user end at the current time and the observation data received at the reference station at the historical time;

[0112] The predicted double-difference distance acquisition module is used to calculate the asynchronous predicted double-difference distance and the user-side INS navigation positioning result based on the received INS data;

[0113] The integrated navigation module is used to calculate the new information based on the double-difference observation value and the predicted double-difference distance, and perform Kalman filter estimation to compensate the user-side INS navigation positioning result to obtain the user-side asynchronous RTK and INS integrated navigation positioning result.

[0114] In this embodiment, the double-difference observation value acquisition module is configured to perform the following steps:

[0115] Obtain the observation data of satellite i and satellite j received by the base station at the historical moment;

[0116] Obtain the observation data of satellite i and satellite j received by the user end at the current moment;

[0117] The observation data of satellite i received by the user terminal at the current time is subtracted from the observation data of satellite i received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value of the corresponding satellite i; the observation data of satellite j received by the user terminal at the current time is subtracted from the observation data of satellite j received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value of the corresponding satellite j;

[0118] The asynchronous double-difference observation value is obtained by subtracting the asynchronous inter-station single-difference observation value corresponding to satellite i from the asynchronous inter-station single-difference observation value corresponding to satellite j.

[0119] In this embodiment, the predicted double-difference distance acquisition module is configured to perform the following steps:

[0120] According to the INS data received at the current moment, the user-side INS navigation positioning result is obtained;

[0121] Calculate the distance between the user terminal and satellite i and satellite j at the current moment;

[0122] Calculate the distances between the reference station and satellite i and satellite j at the historical moment;

[0123] Subtract the distance between the user terminal and satellite i at the current moment from the distance between the reference station and satellite i at the historical moment to obtain the asynchronous prediction station single difference value corresponding to satellite i; subtract the distance between the user terminal and satellite j at the current moment from the distance between the reference station and satellite j at the historical moment to obtain the asynchronous prediction station single difference value corresponding to satellite j;

[0124] The single difference between the asynchronous prediction stations corresponding to satellite i and the single difference between the asynchronous prediction stations corresponding to satellite j are subtracted, and the predicted double difference distance based on asynchronous prediction is obtained according to the calculated difference.

[0125] In this embodiment, the combined navigation module is configured to perform the following steps:

[0126] New information is calculated based on the double difference observation value and the predicted double difference distance;

[0127] Kalman filter estimation is performed based on the new information, and the user-side INS navigation positioning result is compensated according to the estimation result to obtain the user-side asynchronous RTK and INS combined navigation positioning result.

[0128] The embodiment of the present invention further provides a combined navigation and positioning system based on asynchronous differential positioning technology, comprising an RTK module, an INS module and a navigation and positioning module;

[0129] The RTK module is used to transmit the observation data received by itself and the observation data sent by the reference station to the navigation and positioning module;

[0130] The INS module is used to transmit the received INS data to the navigation and positioning module;

[0131] The navigation and positioning module is used to execute the steps of the combined navigation and positioning method based on the asynchronous differential positioning technology as described in the above embodiment.

[0132] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0133] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A combined navigation and positioning method based on asynchronous differential positioning technology, characterized in that: include: S1: Using asynchronous RTK technology, double-difference processing is performed based on the observation data received by the user at the current time and the observation data received by the base station at the historical time to obtain double-difference observation values; S2: Calculate the user-side INS navigation positioning result and the asynchronous predicted double difference distance based on the received INS data; S3: New information is calculated based on the double-difference observation value and the predicted double-difference distance, and Kalman filter estimation is performed to compensate the user-side INS navigation positioning result to obtain the user-side asynchronous RTK and INS combined navigation positioning result.

2. The combined navigation and positioning method based on asynchronous differential positioning technology according to claim 1 is characterized in that: The step S1 specifically includes: Obtain the observation data of satellite i and satellite j received by the base station at the historical moment; Obtain the observation data of satellite i and satellite j received by the user end at the current moment; The observation data of satellite i received by the user terminal at the current time is subtracted from the observation data of satellite i received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value of the corresponding satellite i; the observation data of satellite j received by the user terminal at the current time is subtracted from the observation data of satellite j received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value of the corresponding satellite j; The asynchronous double-difference observation value is obtained by subtracting the asynchronous inter-station single-difference observation value corresponding to satellite i from the asynchronous inter-station single-difference observation value corresponding to satellite j.

3. The combined navigation and positioning method based on asynchronous differential positioning technology according to claim 1, characterized in that: The step S2 specifically includes: According to the INS data received at the current moment, the user-side INS navigation positioning result is obtained; Calculate the distance between the user terminal and satellite i and satellite j at the current moment; Calculate the distances between the reference station and satellite i and satellite j at the historical moment; Subtract the distance between the user terminal and satellite i at the current moment from the distance between the reference station and satellite i at the historical moment to obtain the asynchronous prediction station single difference value corresponding to satellite i; subtract the distance between the user terminal and satellite j at the current moment from the distance between the reference station and satellite j at the historical moment to obtain the asynchronous prediction station single difference value corresponding to satellite j; The single difference between the asynchronous prediction stations corresponding to satellite i and the single difference between the asynchronous prediction stations corresponding to satellite j are subtracted, and the predicted double difference distance based on asynchronous prediction is obtained according to the calculated difference.

4. The combined navigation and positioning method based on asynchronous differential positioning technology according to claim 1, characterized in that: The step S3 specifically includes: New information is calculated based on the double difference observation value and the predicted double difference distance; Kalman filter estimation is performed based on the new information, and the user-side INS navigation positioning result is compensated according to the estimation result to obtain the user-side asynchronous RTK and INS combined navigation positioning result.

5. The combined navigation and positioning method based on asynchronous differential positioning technology according to claim 4 is characterized in that: The Kalman filter state vector is expressed as follows: Among them, δ is a symbol representing the error state, δr, δv and ψ represent the errors of position, velocity and attitude respectively, and δb g and δb a Denote the bias errors of the gyroscope and accelerometer, δs g and δs a denote the scale factor errors of the gyroscope and accelerometer respectively, represents the double-difference ambiguity.

6. A combined navigation and positioning device based on asynchronous differential positioning technology, characterized in that: include: The double-difference observation value acquisition module is used to obtain double-difference observation values ​​by using asynchronous RTK technology and performing double-difference processing based on the observation data received at the user end at the current time and the observation data received at the reference station at the historical time; The predicted double-difference distance acquisition module is used to calculate the asynchronous predicted double-difference distance and the user-side INS navigation positioning result based on the received INS data; The integrated navigation module is used to calculate the new information based on the double-difference observation value and the predicted double-difference distance, and perform Kalman filter estimation to compensate the user-side INS navigation positioning result to obtain the user-side asynchronous RTK and INS integrated navigation positioning result.

7. The combined navigation and positioning device based on the asynchronous differential positioning technology according to claim 6, characterized in that: The double-difference observation value acquisition module is configured to perform the following steps: Obtain the observation data of satellite i and satellite j received by the base station at the historical moment; Obtain the observation data of satellite i and satellite j received by the user end at the current moment; The observation data of satellite i received by the user terminal at the current time is subtracted from the observation data of satellite i received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value corresponding to satellite i; The observation data of satellite j received by the user terminal at the current time is subtracted from the observation data of satellite j received by the reference station at the historical time to obtain the asynchronous inter-station single-difference observation value corresponding to satellite j; The asynchronous double-difference observation value is obtained by subtracting the asynchronous inter-station single-difference observation value corresponding to satellite i from the asynchronous inter-station single-difference observation value corresponding to satellite j.

8. The combined navigation and positioning device based on asynchronous differential positioning technology according to claim 6, characterized in that: The predicted double difference distance acquisition module is configured to perform the following steps: According to the INS data received at the current moment, the user-side INS navigation positioning result is obtained; Calculate the distance between the user terminal and satellite i and satellite j at the current moment; Calculate the distances between the reference station and satellite i and satellite j at the historical moment; Subtract the distance between the user terminal and satellite i at the current moment from the distance between the reference station and satellite i at the historical moment to obtain the asynchronous prediction station single difference value corresponding to satellite i; Subtract the distance between the user terminal and satellite j at the current moment from the distance between the reference station and satellite j at the historical moment to obtain the asynchronous prediction station-to-station single difference value corresponding to satellite j; The single difference between the asynchronous prediction stations corresponding to satellite i and the single difference between the asynchronous prediction stations corresponding to satellite j are subtracted, and the predicted double difference distance based on asynchronous prediction is obtained according to the calculated difference.

9. The combined navigation and positioning device based on the asynchronous differential positioning technology according to claim 6, characterized in that: The integrated navigation module is configured to perform the following steps: New information is calculated based on the double difference observation value and the predicted double difference distance; Kalman filter estimation is performed based on the new information, and the user-side INS navigation positioning result is compensated according to the estimation result to obtain the user-side asynchronous RTK and INS combined navigation positioning result.

10. An integrated navigation system based on asynchronous differential positioning technology, characterized in that: Including RTK module, INS module and navigation and positioning module; The RTK module is used to transmit the observation data received by itself and the observation data sent by the reference station to the navigation and positioning module; The INS module is used to transmit the received INS data to the navigation and positioning module; The navigation and positioning module is used to execute the steps of the combined navigation and positioning method based on the asynchronous differential positioning technology as described in any one of claims 1 to 5.

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