Ambiguity fixing method, device, mobile terminal, storage medium and program product

Abstract

The application provides a method and device for ambiguity fixing, a mobile terminal, a storage medium and a program product, and relates to the technical field of positioning. The method for ambiguity fixing realizes decoupling of the easy fixing characteristics of the wide lane combination and the ionospheric error resistance characteristics of the ionospheric-free combination by respectively constructing wide lane combination observation equations and ionospheric-free combination observation equations. Further, based on the first double-difference integer ambiguity of the wide lane combination and the second double-difference integer ambiguity of the ionospheric-free combination, the double-frequency integer ambiguity of the double-frequency carrier is fixed in layers, the long wavelength characteristics of the wide lane combination and the ionospheric suppression capability of the ionospheric-free combination are synergistically used, the ionospheric delay time-varying error interference on the ambiguity fixing is reduced, the ambiguity fixing success rate and the positioning accuracy stability in the ionospheric active environment are improved, and the high-precision positioning demand of GNSS precise relative positioning is met.

Description

Technical Field

[0001] This application relates to the field of positioning technology, and in particular to a method, apparatus, mobile terminal, storage medium, and program product for fixing ambiguity. Background Technology

[0002] Global Navigation Satellite System (GNSS) precise relative positioning technology is a space positioning technology widely used in high-precision positioning scenarios such as autonomous driving, drone navigation, precision agriculture, surveying and mapping engineering, and disaster monitoring due to its advantages such as high accuracy, high speed, no line-of-sight requirement, all-weather observation capability, and relatively low cost. Currently, GNSS precise relative positioning technology can be divided into short baseline real-time kinematic positioning (RTK) technology and network RTK technology. RTK technology requires integer solutions to ambiguity parameters to obtain high-precision positioning results.

[0003] In related technologies, GNSS precise relative positioning technology, RTK technology typically uses ambiguity parameters at two frequency points for direct search and fixation. The fixation methods mainly include rounding, bootstrapping, and least-squares AMBiguity Decorrelation Adjustment (LAMBDA). Specifically, RTK technology usually relies on dual-frequency observation data (such as L1 and L2 bands) to construct double-difference observation equations between satellites and the receiver, further estimates the floating-point ambiguity solution through Kalman filtering, and then uses LAMBDA to fix the integer ambiguity.

[0004] However, the aforementioned ambiguity fixation methods have a low success rate in scenarios with a relatively active ionosphere, and cannot meet the high-precision positioning requirements of GNSS precise relative positioning. Summary of the Invention

[0005] This application provides a method, apparatus, mobile terminal, storage medium, and program product for ambiguity fixing, which solves the problem that RTK technology in related technologies usually directly uses ambiguity parameters on two frequency points for searching and fixing, resulting in a low success rate of ambiguity fixing in scenarios where the ionosphere is relatively active.

[0006] In a first aspect, this application provides an ambiguity fixing method, comprising: acquiring phase observation data of dual-frequency carriers of dual satellites from dual receivers; constructing a wide-lane combined observation equation and an ionospheric de-escalation combined observation equation based on the phase observation data; fixing a first double-difference integer ambiguity of the wide-lane combination and a second double-difference integer ambiguity of the ionospheric de-escalation combination based on the wide-lane combined observation equation and the ionospheric de-escalation combined observation equation; and fixing the dual-frequency integer ambiguity of the dual-frequency carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity.

[0007] In one possible implementation, the dual-frequency carrier includes a first frequency band carrier and a second frequency band carrier. The dual-frequency integer ambiguity of the dual-frequency carrier is fixed based on a first double-difference integer ambiguity and a second double-difference integer ambiguity, including: calculating a first floating-point ambiguity of the first frequency band carrier and a second floating-point ambiguity of the second frequency band carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity; and fixing the first integer ambiguity of the first frequency band carrier and the second integer ambiguity of the second frequency band carrier based on the first floating-point ambiguity and the second floating-point ambiguity.

[0008] In one possible implementation, based on the wide-lane combined observation equation and the ionosphere-depleted combined observation equation, the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the ionosphere-depleted combination are fixed, including: using Kalman filtering to dynamically estimate the wide-lane combined observation equation to obtain the first double-difference floating-point ambiguity of the wide-lane combination, and performing an integer solution search to fix the first double-difference floating-point ambiguity to obtain the first double-difference integer ambiguity; using Kalman filtering to dynamically estimate the ionosphere-depleted combined observation equation to obtain the second double-difference floating-point ambiguity of the ionosphere-depleted combination, and performing an integer solution search to fix the second double-difference floating-point ambiguity to obtain the second double-difference integer ambiguity.

[0009] In one possible implementation, based on phase observation data, a wide-lane combined observation equation and an ionospheric de-escalation combined observation equation are constructed, including: constructing a double-difference observation equation based on the phase observation data; constructing a wide-lane combined observation equation based on the double-difference observation equation, wherein the wide-lane combined observation equation is generated by linear combination of phase observation data of dual-frequency carriers; and constructing an ionospheric de-escalation combined observation equation based on the double-difference observation equation, wherein the ionospheric de-escalation combined observation equation is generated by linear combination of phase observation data of dual-frequency carriers.

[0010] In one possible implementation, the phase observation data includes phase observation values ​​of a dual-frequency carrier, and the two satellites include a first satellite and a second satellite. Based on the phase observation data, a double-difference observation equation is constructed, including: constructing a first receiver single-difference observation equation for the first satellite and a second receiver single-difference observation equation for the second satellite based on the phase observation values; and constructing a double-difference observation equation based on the first receiver single-difference observation equation and the second receiver single-difference observation equation.

[0011] In one possible implementation, the dual receivers include a base station receiver and a mobile station receiver. Based on the phase observations, a first receiver single-difference observation equation for the first satellite and a second receiver single-difference observation equation for the second satellite are constructed. This includes: calculating the difference between the phase observations of the base station receiver and the mobile station receiver for the first satellite based on the phase observations of the first satellite, thus obtaining the first receiver single-difference observation equation; and calculating the difference between the phase observations of the base station receiver and the mobile station receiver for the second satellite based on the phase observations of the second satellite, thus obtaining the second receiver single-difference observation equation.

[0012] Secondly, this application provides an ambiguity fixing device, comprising:

[0013] The acquisition module is used to acquire phase observation data of dual-frequency carriers of dual satellites from dual receivers;

[0014] The module is used to construct the wide-lane combined observation equation and the ionosphere-depleted combined observation equation based on phase observation data;

[0015] The first fixed module is used to fix the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the ionosphere combination according to the wide-lane combination observation equation and the ionosphere-free combination observation equation.

[0016] The second fixing module is used to fix the dual-frequency integer ambiguity of the dual-frequency carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity.

[0017] In one possible implementation, the dual-frequency carrier includes a first frequency band carrier and a second frequency band carrier. The second fixed module is specifically used to: solve the first floating-point ambiguity of the first frequency band carrier and the second floating-point ambiguity of the second frequency band carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity; and fix the first integer ambiguity of the first frequency band carrier and the second integer ambiguity of the second frequency band carrier based on the first floating-point ambiguity and the second floating-point ambiguity.

[0018] In one possible implementation, the first fixed module is specifically used to: dynamically estimate the wide-lane combined observation equation using Kalman filtering to obtain the first double-difference floating-point ambiguity of the wide-lane combined, and perform integer solution search and fixation on the first double-difference floating-point ambiguity to obtain the first double-difference integer ambiguity; dynamically estimate the ionosphere-depleted combined observation equation using Kalman filtering to obtain the second double-difference floating-point ambiguity of the ionosphere-depleted combined, and perform integer solution search and fixation on the second double-difference floating-point ambiguity to obtain the second double-difference integer ambiguity.

[0019] In one possible implementation, the construction module is specifically used to: construct a double-difference observation equation based on the phase observation data; construct a wide-lane combined observation equation based on the double-difference observation equation, which is generated by linear combination of phase observation data of dual-frequency carriers; and construct an ionospheric despheric combined observation equation based on the double-difference observation equation, which is generated by linear combination of phase observation data of dual-frequency carriers.

[0020] In one possible implementation, the phase observation data includes phase observations of dual-frequency carriers, the two satellites include a first satellite and a second satellite, and the construction module is further configured to: construct a first receiver single-difference observation equation for the first satellite and a second receiver single-difference observation equation for the second satellite based on the phase observations; and construct a double-difference observation equation based on the first receiver single-difference observation equation and the second receiver single-difference observation equation.

[0021] In one possible implementation, the dual receivers include a base station receiver and a rover receiver. The construction module is further configured to: calculate the difference between the phase observations of the base station receiver and the rover receiver to the first satellite based on the phase observations of the first satellite, thereby obtaining the single-difference observation equation for the first receiver; and calculate the difference between the phase observations of the base station receiver and the rover receiver to the second satellite based on the phase observations of the second satellite, thereby obtaining the single-difference observation equation for the second receiver.

[0022] Thirdly, this application provides a mobile terminal, including: a processor and a memory communicatively connected to the processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the ambiguity fixing method provided in the first aspect above.

[0023] Fourthly, this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the ambiguity fixing method provided in the first aspect above.

[0024] Fifthly, this application provides a computer program product, comprising: a computer program that, when executed by a processor, implements the ambiguity fixing method provided in the first aspect above.

[0025] The ambiguity fixing method, apparatus, mobile terminal, storage medium, and program product provided in this application acquire phase observation data of dual-frequency carriers of dual satellites from dual receivers, and construct wide-lane combined observation equations and ionospheric de-escalation combined observation equations based on the phase observation data. Further, based on the wide-lane combined observation equations and ionospheric de-escalation combined observation equations, the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the ionospheric de-escalation combination are fixed. Then, based on the first double-difference integer ambiguity and the second double-difference integer ambiguity, the dual-frequency integer ambiguity of the dual-frequency carriers is fixed. This application constructs wide-lane combined observation equations and ionospheric suppression combined observation equations respectively, thereby decoupling the easy-to-fix characteristics of the wide-lane combination from the anti-ionospheric error characteristics of the ionospheric suppression combination. Furthermore, based on the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the ionospheric suppression combination, the dual-frequency integer ambiguity of the dual-frequency carrier is fixed in layers. This achieves the synergistic effect of the long-wavelength characteristics of the wide-lane combination and the ionospheric suppression capability of the ionospheric suppression combination, reducing the interference of ionospheric delay time-varying errors on ambiguity fixing, and improving the success rate of ambiguity fixing and the stability of positioning accuracy in ionospheric active environments, so as to meet the high-precision positioning requirements of GNSS precise relative positioning. Attached Figure Description

[0026] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0027] Figure 1 A schematic diagram illustrating the application scenarios provided in the embodiments of this application;

[0028] Figure 2 A flowchart illustrating the ambiguity fixing method provided in the embodiments of this application. Figure 1 ;

[0029] Figure 3 A flowchart illustrating the ambiguity fixing method provided in the embodiments of this application. Figure 2 ;

[0030] Figure 4 This is a schematic diagram of the ambiguity fixing device provided in the embodiments of this application;

[0031] Figure 5 This is a schematic diagram of the structure of a mobile terminal provided in an embodiment of this application.

[0032] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0033] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0034] GNSS precise relative positioning technology can be divided into short baseline RTK technology and network RTK technology. Short baseline RTK technology is widely used in high-precision positioning, but its application is limited due to the limited effective operating distance of its baseline, typically within a few kilometers. Network RTK technology can extend the effective operating distance of base stations to tens of kilometers, but it requires multiple reference stations to form a network to calculate error corrections. To obtain high-precision positioning results, RTK technology requires integer solutions for ambiguity parameters. However, interference from the ionospheric environment or poor observation quality from low-cost hardware often makes it difficult to obtain good observation data, thus affecting the fixation of ambiguity parameters and preventing the acquisition of correct integer ambiguity solutions. The accuracy of the fixed ambiguity solution cannot meet the requirements of high-precision positioning.

[0035] Ambiguity parameter estimation based on Kalman filtering can yield floating-point solutions for ambiguity, but the accuracy of the corresponding baseline vector solutions is often unreliable. Only by fixing the floating-point ambiguity solutions to integers can we obtain fixed ambiguity solutions for the baseline vectors, thereby achieving centimeter-level or even millimeter-level positioning accuracy. Therefore, ambiguity verification is of paramount importance.

[0036] In related technologies, traditional RTK technology for GNSS precise relative positioning typically relies on dual-frequency observation data (such as L1 and L2 bands) to construct double-difference observation equations, estimates floating-point ambiguities using Kalman filtering, and then uses the LAMBDA method to fix integer ambiguities. However, in ionospherically active scenarios, traditional RTK technology often struggles to effectively eliminate ionospheric errors in the double-difference observation equations, resulting in large ionospheric residuals in the ambiguity parameters. This leads to insufficient accuracy in the floating-point ambiguity solution, making it impossible to obtain reliable integer ambiguity solutions using the LAMBDA method. Consequently, the success rate of ambiguity fixation is low, affecting positioning accuracy and failing to meet the high-precision positioning requirements of GNSS precise relative positioning.

[0037] Based on the problems existing in related technologies, the embodiments of this application adopt a method of fixing ambiguity by combining a wide-lane-assisted ionospheric suppression combination. After fixing the double-difference integer ambiguity of the wide-lane combination and the double-difference integer ambiguity of the ionospheric suppression combination, the integer ambiguity of the dual-frequency carrier is fixed in layers. This achieves the synergistic effect of the long wavelength characteristics of the wide-lane combination and the ionospheric suppression capability of the ionospheric suppression combination, reduces the interference of ionospheric delay time-varying error on ambiguity fixing, and improves the success rate of ambiguity fixing and the stability of positioning accuracy in ionospheric active environments, so as to meet the high-precision positioning requirements of GNSS precise relative positioning.

[0038] The application scenarios of the embodiments of this application will be described below first.

[0039] The ambiguity fixing method provided in this application is applicable to GNSS precise relative positioning scenarios, and is especially suitable for high-precision positioning scenarios with extremely high positioning accuracy requirements, such as autonomous driving, UAV navigation, precision agriculture, surveying and mapping engineering, and disaster monitoring in ionospheric active environments.

[0040] Figure 1 This is a schematic diagram illustrating an application scenario provided in an embodiment of this application. For example... Figure 1 As shown, the application scenarios applicable to the ambiguity fixing method provided in this application include a first satellite, a second satellite, a reference station system, and a mobile terminal. The reference station system and the mobile terminal are communicatively connected; the reference station system is equipped with a reference station receiver, and the mobile terminal is equipped with a mobile station receiver.

[0041] For example, the first and second satellites can be GNSS satellites that broadcast dual-frequency carrier signals, which can be signal sources for high-precision positioning.

[0042] For example, the base station receiver and the rover receiver can be dual-frequency GNSS receivers used to acquire phase observation data from the first satellite and the second satellite. The base station receiver is fixed at a known coordinate point, meaning its coordinates are known, while the rover receiver's coordinates are unknown.

[0043] For example, the phase observation data collected by the base station receiver can be transmitted to the mobile terminal through the base station system and used in conjunction with the phase observation data of the mobile station receiver for positioning calculation.

[0044] For example, the mobile terminal can be an autonomous vehicle, a drone, or agricultural machinery.

[0045] The specific implementation of the ambiguity fixing method provided in this application will be described in detail below with reference to specific embodiments.

[0046] Figure 2 A flowchart illustrating the ambiguity fixing method provided in the embodiments of this application. Figure 1 .like Figure 2 As shown, a specific implementation of this ambiguity fixing method may include the following steps:

[0047] S201: Acquire phase observation data of dual-frequency carriers of dual satellites from dual receivers.

[0048] For example, dual receivers may include the above-described Figure 1 The base station receiver and rover receiver shown herein, the dual satellites may include the aforementioned Figure 1 The first and second satellites shown.

[0049] For example, the dual-frequency carrier may include a first frequency band carrier and a second frequency band carrier, and the phase observation data may include the phase observation values ​​of the first frequency band carrier and the second frequency band carrier transmitted by the first satellite received by the base station receiver, the phase observation values ​​of the first frequency band carrier and the second frequency band carrier transmitted by the second satellite received by the base station receiver, the phase observation values ​​of the first frequency band carrier and the second frequency band carrier transmitted by the first satellite received by the mobile station receiver, and the phase observation values ​​of the first frequency band carrier and the second frequency band carrier transmitted by the second satellite received by the mobile station receiver.

[0050] It is understandable that the phase observation data of dual-frequency carriers can be phase observation data synchronously acquired by dual receivers from dual satellites at the same epoch.

[0051] S202. Based on phase observation data, construct the wide-lane combined observation equation and the ionosphere-depleted combined observation equation.

[0052] For example, the wide-lane combined observation equation can be expressed by the following formula:

[0053]

[0054] in, This represents the equivalent wavelength of the wide-lane combination. This represents the first double-difference phase observation of the wide-lane combination. This represents the receiver's single-difference phase observation value corresponding to the carrier in the first frequency band. This represents the receiver's single-difference phase observation value corresponding to the second frequency band carrier. Represents the double-difference geometric distance. This represents the first double-difference integer ambiguity of the wide-lane combination.

[0055] For example, This can be expressed by the following formula:

[0056]

[0057] in, This indicates the wavelength of the carrier wave in the first frequency band. This indicates the wavelength of the second frequency band carrier.

[0058] For example, This can be expressed by the following formula:

[0059]

[0060] in, This represents the double-difference integer ambiguity of the first frequency band carrier. This represents the receiver single-difference integer ambiguity of the first frequency band carrier. This represents the double-difference integer ambiguity of the second frequency band carrier. This represents the receiver single-difference integer ambiguity of the second frequency band carrier.

[0061] For example, the combined observation equation for de-ionization can be expressed by the following formula:

[0062]

[0063] in, Indicates the deionization combination coefficient. This represents the second double-difference integer ambiguity of the deionization combination.

[0064] For example, This can be expressed by the following formula:

[0065]

[0066] Understandable, It is through the wavelength of the dual-frequency carrier, that is, the wavelength of the first frequency band carrier. wavelength of the second frequency band carrier The calculated weighting factor is used to offset the effect of ionospheric delay on phase observations.

[0067] For example, This can be expressed by the following formula:

[0068]

[0069] One possible implementation of this step is to linearly combine the phase observation data of the dual-frequency carrier to generate the wide-lane combined observation equation and the ionosphere-depleted combined observation equation, respectively.

[0070] It is understood that in the ambiguity fixing method provided in this application embodiment, by constructing wide-lane combined observation equations and ionospheric de-escalation combined observation equations respectively, the wide-lane combined observation equations can reduce the ambiguity search space by extending the wavelength, thereby improving the success rate of wide-lane ambiguity fixing. The ionospheric de-escalation combined observation equations eliminate ionospheric delay errors through linear weighting, thereby improving the success rate of ionospheric de-escalation ambiguity fixing. That is, by utilizing the high fixing success rate of wide-lane ambiguity and the ionospheric suppression capability of ionospheric de-escalation, the dual-frequency integer ambiguity of dual-frequency carriers is solved in layers, thereby achieving high-precision positioning in an ionospheric active environment.

[0071] S203, based on the wide-lane combined observation equation and the deionization combined observation equation, fix the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the deionization combination.

[0072] The formulas for expressing the first and second double-difference integer ambiguities are similar to those described above, and will not be repeated here.

[0073] In this step, one possible implementation is to: fix the first double-difference integer ambiguity of the wide-lane combination according to the wide-lane combination observation equation; and fix the second double-difference integer ambiguity of the deionization combination according to the deionization combination observation equation.

[0074] S204, fix the dual-frequency integer ambiguity of the dual-frequency carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity.

[0075] It is understandable that the dual-frequency integer ambiguity of a dual-frequency carrier includes the first integer ambiguity of the first frequency band carrier and the second integer ambiguity of the second frequency band carrier.

[0076] In this step, one possible implementation is as follows: based on the expressions for the first and second double-difference integer ambiguities, the double-difference integer ambiguities of the first frequency band carrier can be derived. And the double-difference integer ambiguity of the second frequency band carrier. In conjunction with the original integer ambiguity known from the base station, the double-difference integer ambiguity based on the first frequency band carrier is calculated. Double-difference integer ambiguity of second-band carrier By reversing the process, the first floating-point ambiguity of the first frequency band carrier (i.e., the original floating-point ambiguity of the first frequency band) and the second floating-point ambiguity of the second frequency band carrier (i.e., the original floating-point ambiguity of the second frequency band) are calculated. Then, integer solutions are searched and fixed for the first and second floating-point ambiguities respectively to obtain the first integer ambiguity of the first frequency band carrier (i.e., the original integer ambiguity of the first frequency band carrier) and the second integer ambiguity of the second frequency band carrier (i.e., the original integer ambiguity of the second frequency band carrier).

[0077] For example, the double-difference integer ambiguity of the first frequency band carrier. This can be expressed by the following formula:

[0078]

[0079] For example, the double-difference integer ambiguity of the second frequency band carrier. This can be expressed by the following formula:

[0080]

[0081] in, This represents the first integer cycle ambiguity of the first frequency band carrier, i.e., the original integer cycle ambiguity of the first frequency band carrier. This represents the second integer ambiguity of the second frequency band carrier, which is the original integer ambiguity of the second frequency band carrier.

[0082] In this embodiment, by constructing wide-lane combined observation equations and ionospheric suppression combined observation equations respectively, the easy-to-fix characteristics of the wide-lane combination and the anti-ionospheric error characteristics of the ionospheric suppression combination are decoupled. Furthermore, based on the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the ionospheric suppression combination, the dual-frequency integer ambiguity of the dual-frequency carrier is fixed in layers. This achieves the synergistic effect of the long-wavelength characteristics of the wide-lane combination and the ionospheric suppression capability of the ionospheric suppression combination, reduces the interference of ionospheric delay time-varying errors on ambiguity fixing, and improves the success rate of ambiguity fixing and the stability of positioning accuracy in ionospheric active environments, so as to meet the high-precision positioning requirements of GNSS precise relative positioning.

[0083] It is understood that the ambiguity fixing method provided in this application significantly improves the success rate of ambiguity fixing in ionospherically active environments by solving the observation equations of the wide-lane combination and the ionospheric de-escalation combination in a hierarchical manner. Specifically, the long-wavelength characteristic of the wide-lane combination observation equation reduces the ambiguity search space and improves the success rate of fixing wide-lane ambiguity; the ionospheric de-escalation combination observation equation provides a high-precision model for ambiguity fixing by offsetting ionospheric delay errors. It is understood that in the hierarchical solution process, fixing the wide-lane ambiguity provides constraints for solving the ionospheric de-escalation ambiguity, while fixing the ionospheric de-escalation ambiguity further verifies the rationality of the wide-lane ambiguity, forming a two-way verification mechanism. Through the synergistic effect of the wide-lane combination and the ionospheric de-escalation combination, the fixing failure problem caused by ionospheric residuals when directly fixing dual-frequency ambiguities in traditional methods can be effectively avoided, thereby achieving high-precision positioning in ionospherically active scenarios.

[0084] Optionally, the dual-frequency carrier includes a first frequency band carrier and a second frequency band carrier.

[0085] Optionally, step S204, which fixes the dual-frequency integer ambiguity of the dual-frequency carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity, can be implemented as follows: based on the first double-difference integer ambiguity and the second double-difference integer ambiguity, calculate the first floating-point ambiguity of the first frequency band carrier and the second floating-point ambiguity of the second frequency band carrier; based on the first floating-point ambiguity and the second floating-point ambiguity, fix the first integer ambiguity of the first frequency band carrier and the second integer ambiguity of the second frequency band carrier.

[0086] The specific implementation of solving the first floating-point ambiguity of the first frequency band carrier and the second floating-point ambiguity of the second frequency band carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity is similar to that described above, and will not be repeated here.

[0087] For example, based on the first floating-point ambiguity and the second floating-point ambiguity, one possible implementation of fixing the first integer ambiguity of the first frequency band carrier and the second integer ambiguity of the second frequency band carrier can be: rounding the first floating-point ambiguity and the second floating-point ambiguity to obtain integer solutions, respectively, to obtain the first integer ambiguity of the first frequency band carrier and the second integer ambiguity of the second frequency band carrier.

[0088] In this embodiment, the first floating-point ambiguity of the first frequency band carrier and the second floating-point ambiguity of the second frequency band carrier are calculated based on the first double-difference integer ambiguity and the second double-difference integer ambiguity. By leveraging the convergent characteristics of wide-lane combination with long wavelength and the anti-ionospheric error characteristics of de-ionization combination, the calculation accuracy and robustness of the first and second floating-point ambiguities are effectively improved. Furthermore, based on the first and second floating-point ambiguities, the first integer ambiguity of the first frequency band carrier and the second integer ambiguity of the second frequency band carrier are fixed, thereby improving the success rate of fixing the first and second integer ambiguities and enhancing the accuracy and stability of GNSS precise relative positioning in ionospheric active environments, meeting the needs of high-precision positioning scenarios such as autonomous driving and UAV navigation.

[0089] Optionally, step S203, based on the wide-lane combined observation equation and the ionosphere-depleted combined observation equation, can be implemented in the following way: The wide-lane combined observation equation is dynamically estimated using Kalman filtering to obtain the first double-difference floating-point ambiguity of the wide-lane combined observation equation, and the first double-difference floating-point ambiguity is fixed by integer solution search to obtain the first double-difference integer ambiguity; the ionosphere-depleted combined observation equation is dynamically estimated using Kalman filtering to obtain the second double-difference floating-point ambiguity of the ionosphere-depleted combined observation equation, and the second double-difference floating-point ambiguity is fixed by integer solution search to obtain the second double-difference integer ambiguity.

[0090] The combined observation equations for wide-lane and deionized ionosphere are similar to those described above, and will not be repeated here.

[0091] For example, LAMBDA is used to search and fix the first double-difference floating-point ambiguity with integer solutions to obtain the first double-difference integer ambiguity; LAMBDA is used to search and fix the second double-difference floating-point ambiguity with integer solutions to obtain the second double-difference integer ambiguity.

[0092] For example, the ambiguity fixing method provided in this application embodiment can simultaneously perform filtering and integer solution search fixing of wide-lane ambiguity and filtering and integer solution search fixing of ionospheric ambiguity through parallel multi-threaded execution, thereby shortening the ambiguity fixing time and improving the ambiguity fixing efficiency, which is suitable for real-time positioning requirements in highly dynamic scenarios.

[0093] In this embodiment, Kalman filtering is used to dynamically estimate the wide-lane combined observation equation to obtain the first double-difference floating-point ambiguity of the wide-lane combination. The first double-difference floating-point ambiguity is then fixed using an integer solution search to obtain the first double-difference integer-cycle ambiguity. The long-wavelength characteristic of the wide-lane combined observation equation reduces the ambiguity search space and improves the success rate of fixing the second double-difference integer-cycle ambiguity. Kalman filtering is also used to dynamically estimate the ionospheric de-escalation combined observation equation to obtain the second double-difference floating-point ambiguity of the ionospheric de-escalation combination. The second double-difference floating-point ambiguity is then fixed using an integer solution search to obtain the second double-difference integer-cycle ambiguity. The ionospheric de-escalation combined observation equation provides a high-precision model for ambiguity fixing by offsetting ionospheric delay errors, thus improving the fixing accuracy of the second double-difference integer-cycle ambiguity.

[0094] The following is combined with Figure 3 The specific implementation method of step S202, which constructs the wide-lane combined observation equation and the ionosphere-depleting combined observation equation based on the phase observation data, is described in detail.

[0095] Figure 3 A flowchart illustrating the ambiguity fixing method provided in the embodiments of this application. Figure 2 .like Figure 3 As shown, a specific implementation of this ambiguity fixing method, which constructs the wide-lane combined observation equation and the ionosphere-depleting combined observation equation based on phase observation data, may include the following steps:

[0096] S301, Based on the phase observation data, construct the double-difference observation equation.

[0097] Optionally, the phase observation data includes phase observations of dual-frequency carrier waves, with the two satellites comprising a first satellite and a second satellite. The phase observations of the dual-frequency carrier waves, the first satellite, and the second satellite are similar to those described above and will not be repeated here.

[0098] Optionally, this step may include the following steps:

[0099] S3011, based on the phase observation values, construct the first receiver single-difference observation equation for the first satellite and the second receiver single-difference observation equation for the second satellite.

[0100] For example, the phase observations include phase observations of the first satellite and phase observations of the second satellite. Specifically, the phase observations of the first satellite include phase observations of the first frequency band carrier and the second frequency band carrier transmitted by the first satellite, received by the base station receiver, and phase observations of the first frequency band carrier and the second frequency band carrier transmitted by the first satellite, received by the mobile station receiver. The phase observations of the second satellite include phase observations of the first frequency band carrier and the second frequency band carrier transmitted by the second satellite, received by the base station receiver, and phase observations of the first frequency band carrier and the second frequency band carrier transmitted by the second satellite, received by the mobile station receiver.

[0101] Optionally, one possible implementation of this step is as follows: based on the phase observation values ​​of the first satellite, calculate the difference between the phase observation values ​​of the base station receiver and the rover receiver for the first satellite to obtain the single-difference observation equation for the first receiver; based on the phase observation values ​​of the second satellite, calculate the difference between the phase observation values ​​of the base station receiver and the rover receiver for the second satellite to obtain the single-difference observation equation for the second receiver.

[0102] For example, the single-difference observation equation for the first receiver can be expressed by the following formula:

[0103]

[0104] in, This indicates the wavelength of the carrier wave in the first frequency band. This represents the difference in phase observations of the first satellite between the base station receiver and the rover receiver. This represents the difference between the geometric distance between the reference receiver and the first satellite, and the geometric distance between the rover receiver and the first satellite. This represents the receiver single-difference integer ambiguity of the first frequency band carrier.

[0105] It is understandable that the original observation equation for the first carrier frequency band corresponding to the single-difference observation equation of the first receiver can be:

[0106]

[0107] For example, the single-difference observation equation for the second receiver can be expressed by the following formula:

[0108]

[0109] in, Indicates the wavelength of the second frequency band carrier. This represents the difference in phase observations of the second satellite between the base station receiver and the rover receiver. This represents the difference between the geometric distance between the reference receiver and the second satellite, and the geometric distance between the rover receiver and the second satellite. This represents the receiver single-difference integer ambiguity of the second frequency band carrier.

[0110] It is understandable that the original observation equation for the second carrier frequency band corresponding to the single-difference observation equation of the second receiver can be:

[0111]

[0112] S3012, construct a double-difference observation equation based on the single-difference observation equation of the first receiver and the single-difference observation equation of the second receiver.

[0113] For example, the double-difference observation equation for the first satellite can be expressed by the following formula:

[0114]

[0115] For example, the double-difference observation equation for the second satellite can be expressed by the following formula:

[0116]

[0117] S302. Based on the double-difference observation equation, a wide-lane combined observation equation is constructed. This wide-lane combined observation equation is generated by linear combination of phase observation data of dual-frequency carriers.

[0118] The specific implementation method is similar to that described above, and will not be repeated here.

[0119] S303. Based on the double-difference observation equation, the ionospheric desiccation combined observation equation is constructed. The ionospheric desiccation combined observation equation is generated by linear combination of phase observation data of dual-frequency carriers.

[0120] The specific implementation method is similar to that described above, and will not be repeated here.

[0121] It is understood that there is no specific order between steps S302 and S303. In some embodiments, steps S302 and S303 can be executed simultaneously based on parallel multi-threaded or distributed computing methods.

[0122] In this embodiment, a double-difference observation equation is constructed based on phase observation data, and a wide-lane combined observation equation is constructed based on the double-difference observation equation. Based on the double-difference observation equation, an ionospheric descrambling combined observation equation is constructed. This decouples the easy-to-fix characteristics of the wide-lane combination from the anti-ionospheric error characteristics of the ionospheric descrambling combination, thereby improving the ambiguity fixation success rate and positioning accuracy stability in an active ionospheric environment.

[0123] The following are embodiments of the apparatus described in this application, which can be used to execute the embodiments of the method described in this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0124] Figure 4 This is a schematic diagram of the ambiguity fixing device provided in an embodiment of this application. Figure 4 As shown, the ambiguity fixing device includes an acquisition module 410, a construction module 420, a first fixing module 430, and a second fixing module 440.

[0125] The acquisition module 410 is used to acquire phase observation data of dual frequency carriers of dual satellites from dual receivers;

[0126] Module 420 is used to construct the wide-lane combined observation equation and the ionosphere-depleted combined observation equation based on phase observation data;

[0127] The first fixed module 430 is used to fix the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the ionosphere combination according to the wide-lane combination observation equation and the ionosphere-free combination observation equation.

[0128] The second fixing module 440 is used to fix the dual-frequency integer ambiguity of the dual-frequency carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity.

[0129] In one possible implementation, the dual-frequency carrier includes a first frequency band carrier and a second frequency band carrier. The second fixing module 440 is specifically used to: solve the first floating-point ambiguity of the first frequency band carrier and the second floating-point ambiguity of the second frequency band carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity; and fix the first integer ambiguity of the first frequency band carrier and the second integer ambiguity of the second frequency band carrier based on the first floating-point ambiguity and the second floating-point ambiguity.

[0130] In one possible implementation, the first fixing module 430 is specifically used to: dynamically estimate the wide-lane combined observation equation using Kalman filtering to obtain the first double-difference floating-point ambiguity of the wide-lane combined, and fix the first double-difference floating-point ambiguity by searching for integer solutions to obtain the first double-difference integer ambiguity; dynamically estimate the ionosphere-depleted combined observation equation using Kalman filtering to obtain the second double-difference floating-point ambiguity of the ionosphere-depleted combined, and fix the second double-difference floating-point ambiguity by searching for integer solutions to obtain the second double-difference integer ambiguity.

[0131] In one possible implementation, the construction module 420 is specifically used to: construct a double-difference observation equation based on the phase observation data; construct a wide-lane combined observation equation based on the double-difference observation equation, which is generated by linear combination of phase observation data of dual-frequency carriers; and construct an ionospheric despheric combined observation equation based on the double-difference observation equation, which is generated by linear combination of phase observation data of dual-frequency carriers.

[0132] In one possible implementation, the phase observation data includes phase observation values ​​of a dual-frequency carrier, the two satellites include a first satellite and a second satellite, and the construction module 420 is further configured to: construct a first receiver single-difference observation equation for the first satellite and a second receiver single-difference observation equation for the second satellite based on the phase observation values; and construct a double-difference observation equation based on the first receiver single-difference observation equation and the second receiver single-difference observation equation.

[0133] In one possible implementation, the dual receivers include a base station receiver and a rover receiver. The construction module 420 is further configured to: calculate the difference between the phase observations of the base station receiver and the rover receiver to the first satellite based on the phase observations of the first satellite, thereby obtaining a single-difference observation equation for the first receiver; and calculate the difference between the phase observations of the base station receiver and the rover receiver to the second satellite based on the phase observations of the second satellite, thereby obtaining a single-difference observation equation for the second receiver.

[0134] The ambiguity fixing device provided in this application embodiment can be used to execute the method steps of the above method embodiment. The specific implementation and technical effects are similar, and will not be described again here.

[0135] Figure 5 This is a schematic diagram of the structure of a mobile terminal provided in an embodiment of this application. Figure 5 As shown, the mobile terminal 50 provided in this embodiment includes at least one processor 501 and a memory 502. Optionally, the mobile terminal 50 further includes a communication component 503. The processor 501, memory 502, and communication component 503 are connected via a bus 504.

[0136] In a specific implementation, at least one processor 501 executes computer execution instructions stored in memory 502, causing at least one processor 501 to perform the above-described method.

[0137] The specific implementation process of processor 501 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0138] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0139] The memory may include random access memory (RAM) and non-volatile memory (NVM), such as at least one disk storage device.

[0140] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0141] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0142] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0143] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0144] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0145] The division of units is merely a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0146] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0147] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0148] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0149] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0150] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A method for fixing ambiguity, characterized in that, include: Acquire phase observation data of dual-frequency carriers from dual satellites using dual receivers; Based on the phase observation data, wide-lane combined observation equations and ionosphere depletion combined observation equations are constructed. Based on the wide-lane combined observation equation and the deionization combined observation equation, fix the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the deionization combination; The dual-frequency integer ambiguity of the dual-frequency carrier is fixed based on the first double-difference integer ambiguity and the second double-difference integer ambiguity.

2. The ambiguity fixing method according to claim 1, characterized in that, The dual-frequency carrier includes a first frequency band carrier and a second frequency band carrier. Fixing the dual-frequency integer ambiguity of the dual-frequency carrier based on the first double-difference integer ambiguity and the second double-difference integer ambiguity includes: Based on the first double-difference integer ambiguity and the second double-difference integer ambiguity, the first floating-point ambiguity of the first frequency band carrier and the second floating-point ambiguity of the second frequency band carrier are solved; Based on the first floating-point ambiguity and the second floating-point ambiguity, the first integer cycle ambiguity of the first frequency band carrier and the second integer cycle ambiguity of the second frequency band carrier are fixed.

3. The ambiguity fixing method according to claim 1, characterized in that, The step of fixing the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the ionosphere-depleted combination based on the wide-lane combination observation equation and the ionosphere-depleted combination observation equation includes: Kalman filtering is used to dynamically estimate the observation equation of the wide lane combination to obtain the first double-difference floating-point ambiguity of the wide lane combination, and the first double-difference floating-point ambiguity is fixed by integer solution search to obtain the first double-difference integer ambiguity. Kalman filtering is used to dynamically estimate the observation equations of the de-ionization combination to obtain the second double-difference floating-point ambiguity of the de-ionization combination. The second double-difference floating-point ambiguity is then searched and fixed by integer solutions to obtain the second double-difference integer ambiguity.

4. The ambiguity fixing method according to any one of claims 1 to 3, characterized in that, The process of constructing the wide-lane combined observation equation and the ionosphere-depleting combined observation equation based on the phase observation data includes: Based on the phase observation data, a double-difference observation equation is constructed; Based on the double-difference observation equation, the wide-lane combined observation equation is constructed, which is generated by linear combination of the phase observation data of the dual-frequency carrier. Based on the double-difference observation equation, the ionospheric desiccation combined observation equation is constructed. The ionospheric desiccation combined observation equation is generated by linear combination of the phase observation data of the dual-frequency carrier.

5. The ambiguity fixing method according to claim 4, characterized in that, The phase observation data includes the phase observation values ​​of the dual-frequency carrier, the dual satellites include a first satellite and a second satellite, and the construction of a double-difference observation equation based on the phase observation data includes: Based on the phase observation values, construct the first receiver single-difference observation equation for the first satellite and the second receiver single-difference observation equation for the second satellite; The double-difference observation equation is constructed based on the first receiver single-difference observation equation and the second receiver single-difference observation equation.

6. The ambiguity fixing method according to claim 5, characterized in that, The dual receivers include a base station receiver and a rover station receiver. The construction of the first receiver single-difference observation equation for the first satellite and the second receiver single-difference observation equation for the second satellite, based on the phase observation values, includes: Based on the phase observation value of the first satellite, the difference between the phase observation values ​​of the base station receiver and the rover receiver for the first satellite is calculated to obtain the single-difference observation equation of the first receiver; Based on the phase observation values ​​of the second satellite, the difference between the phase observation values ​​of the base station receiver and the rover receiver for the second satellite is calculated, and the single-difference observation equation of the second receiver is obtained.

7. A device for fixing ambiguity, characterized in that, include: The acquisition module is used to acquire phase observation data of dual-frequency carriers of dual satellites from dual receivers; The construction module is used to construct the wide-lane combined observation equation and the ionosphere-depleted combined observation equation based on the phase observation data; The first fixed module is used to fix the first double-difference integer ambiguity of the wide-lane combination and the second double-difference integer ambiguity of the ionosphere combination according to the wide-lane combination observation equation and the ionosphere-depleted combination observation equation. The second fixing module is used to fix the dual-frequency integer ambiguity of the dual-frequency carrier based on the first dual-difference integer ambiguity and the second dual-difference integer ambiguity.

8. A mobile terminal, characterized in that, include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the ambiguity fixing method as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the ambiguity fixing method as described in any one of claims 1 to 6.

10. A computer program product, characterized in that, include: A computer program, which, when executed by a processor, implements the ambiguity fixing method as described in any one of claims 1 to 6.

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