Methods, apparatus, equipment, and computer storage media for static station cycle slip detection

Abstract

This disclosure provides a method, apparatus, device, and computer storage medium for static station cycle slip detection. The method includes, during epoch-time difference calculation based on carrier phase observations, eliminating the satellite-to-ground distance in the epoch-time difference process using known coordinate data from the static station to obtain a first observation equation; calculating the difference between the selected reference satellite and the observed satellite based on the first observation equation to obtain a second observation equation; performing epoch-time difference calculation again based on the second observation equation to obtain epoch-time difference observations; and determining cycle slips based on the epoch-time difference observations. This embodiment can eliminate the satellite-to-ground distance using known coordinates from the static station during the epoch-time difference calculation process, thereby reducing the estimated parameters of coordinate changes and avoiding positional deviations; and by performing epoch-time difference calculation after inter-satellite difference calculation, it weakens the influence of residual errors, solves the problem of false or missed cycle slip detection when the data sampling rate is low, and can detect small cycle slips, making it highly applicable.

Description

Technical Field

[0001] This disclosure belongs to the field of satellite positioning technology, and in particular relates to a method, apparatus, equipment and computer storage medium for static station cycle slip detection. Background Technology

[0002] High-precision positioning, orbit determination, and satellite clock error calculation in GNSS (Global Navigation Satellite System) are generally based on carrier phase observations. While carrier phase observations offer high accuracy, they are prone to cycle slips. If cycle slips are not properly addressed, they will severely contaminate the phase observations, leading to significant deviations in the calculation results. Accurately detecting or correctly correcting cycle slips allows for full utilization of the phase observations, resulting in high-precision calculations. Therefore, cycle slip detection and correction are crucial for high-precision applications.

[0003] Among the current cycle slip detection methods, two methods are commonly used:

[0004] One approach involves linearly combining different observations, such as the TurboEdit method, which uses GF and MW combinations for cycle slip detection and repair. However, this method has limitations. For the MW combination, the introduction of noisy pseudorange observations generally prevents the detection of small cycle slips, making it only suitable for large ones. The GF combination also presents challenges in detecting cycle slips in certain combinations (insensitive cycle slips) and cannot be applied to single-frequency observations. Therefore, this method has its limitations.

[0005] The second method is the inter-epoch difference method, which takes into account the small variations in errors such as ionospheric error, tropospheric error, and hardware delay between epochs. It constructs the phase observation difference between epochs and uses least squares to detect and repair cycle slips. This method is only suitable for high sampling rates (such as 1Hz) and performs poorly for low sampling rates. Furthermore, when multiple cycle slips exist, due to the error balancing characteristics of least squares, the least squares method may result in the final residual not reflecting the true error, making it impossible to determine which satellite experienced the cycle slip based on the residual. Therefore, this method also has its limitations. Summary of the Invention

[0006] This disclosure provides a method, apparatus, device, and computer storage medium for detecting cycle slips at static stations. It has high applicability and can detect and repair small cycle slips.

[0007] In a first aspect, embodiments of this disclosure provide a method for detecting cycle slip at a static station, the method comprising:

[0008] When performing inter-epoch difference based on carrier phase observations, the satellite-to-ground distance in the inter-epoch difference process is eliminated using the known coordinate data of the static station, resulting in the first observation equation; the satellite-to-ground distance is the distance from the observation satellite to the ground station.

[0009] Based on the selected reference satellite, the difference between the reference satellite and the observed satellite is calculated using the first observation equation to obtain the second observation equation;

[0010] Based on the second observation equation, inter-epoch difference is performed again to obtain inter-epoch difference observations;

[0011] Cycle slip determination is performed based on interepoch difference observations.

[0012] In some embodiments, when performing inter-epoch difference based on carrier phase observations, the satellite-to-ground distance in the inter-epoch difference process is eliminated using known coordinate data from static stations, resulting in a first observation equation, including:

[0013] Based on the carrier phase observations, an inter-epoch difference is performed using a pre-constructed inter-epoch differential phase observation equation;

[0014] The satellite-to-Earth distance is calculated using the known coordinate data from the static station. This value is then substituted into the pre-constructed inter-epoch differential phase observation equation to obtain the inter-epoch first-order differential equation that eliminates the satellite-to-Earth distance, which serves as the first observation equation.

[0015] In some embodiments, the pre-constructed inter-epoch differential phase observation equation is:

[0016]

[0017] Where λ is the carrier wavelength, and Δ is the inter-epoch difference operator. The carrier phase observations are expressed in weeks, where ρ is the satellite-to-Earth distance, c is the speed of light, and t is the carrier phase observation. r denoted as the receiver clock bias of the static station, N as the carrier phase ambiguity, ε as the observation noise, and Δε as the epochal variation including multiple errors.

[0018] The first-order difference equation between epochs is obtained by eliminating the satellite-to-Earth distance based on the known coordinates of the static station; the first-order difference equation between epochs is:

[0019]

[0020] In some embodiments, based on a selected reference satellite, a difference calculation is performed between the reference satellite and the observed satellite using a first observation equation to obtain a second observation equation, including:

[0021] Select the satellite with the highest elevation angle as the reference satellite;

[0022] Based on the first difference equation between epochs, the inter-satellite difference calculation between the reference satellite and the observation satellite is performed to construct the inter-satellite single difference observation equation. The inter-satellite single difference observation equation is obtained by eliminating the relative change of receiver clock error between epochs of the static station through inter-satellite difference calculation. The inter-satellite single difference observation equation serves as the second observation equation.

[0023] In some embodiments, the inter-satellite single-difference observation equation is:

[0024]

[0025] Where i and j represent the reference satellite and the observation satellite, respectively, for inter-satellite difference; λ is the carrier wavelength, and Δ is the inter-epoch difference operator. Here, N represents the carrier phase observations in weeks, ε represents the observation noise, and Δε represents the epochal variation that includes multiple errors.

[0026] In some embodiments, inter-epoch difference is performed again based on the second observation equation to obtain inter-epoch difference observations, including:

[0027] Based on the second observation equation, a second difference is performed between epochs to obtain the second difference observations between epochs.

[0028] In some embodiments, the interepoch quadratic difference phase observation equation is:

[0029]

[0030] Where t and t-1 represent the current epoch and the previous epoch, respectively; λ is the carrier wavelength; and Δ is the inter-epoch difference operator. Here, N represents the carrier phase observations in weeks, ε represents the carrier phase ambiguity, Δε represents the observation noise, and Δε represents the epochal variation that includes multiple errors.

[0031] Based on the inter-epoch quadratic difference phase observation equation, the inter-epoch difference observations are calculated.

[0032] In some embodiments, cycle slip determination is performed based on inter-epoch difference observations, including:

[0033] Based on the inter-epoch difference observations, cycle slips are determined using preset cycle slip determination rules. The preset cycle slip determination rules include: setting a determination threshold for cycle slips; when the absolute value of the inter-epoch difference observations is greater than the determination threshold, a cycle slip is determined to have occurred.

[0034] In some embodiments, after determining cycle slips based on inter-epoch difference observations, the method further includes:

[0035] After determining that a cycle slip has occurred, a repair determination is made according to the preset repair determination rules.

[0036] In some embodiments, the preset repair determination rule includes: by setting a rounding threshold, when the absolute value of the difference between the inter-epoch difference observation and the rounded value of the inter-epoch difference observation is less than the rounding threshold, the rounded value of the inter-epoch difference observation is used for cycle slip repair.

[0037] Secondly, embodiments of this disclosure provide an apparatus for detecting static station cycle slip, the apparatus comprising:

[0038] The first observation equation acquisition module is used to eliminate the satellite-to-ground distance in the inter-epoch difference process by using the known coordinate data of the static station when performing inter-epoch difference based on the carrier phase observation value, and obtain the first observation equation; the satellite-to-ground distance is the distance from the observation satellite to the ground static station;

[0039] The second observation equation acquisition module is used to calculate the difference between the reference star and the observed satellite based on the first observation equation, according to the selected reference star, to obtain the second observation equation;

[0040] The difference module is used to perform inter-epoch difference again based on the second observation equation to obtain inter-epoch difference observations.

[0041] The first determination module is used to determine cycle slips based on interepoch difference observations.

[0042] In some embodiments, the apparatus further includes:

[0043] The second determination module is used to perform repair determination according to preset repair determination rules after a cycle slip is determined.

[0044] Thirdly, this disclosure provides a device for detecting static station cycle slips, the device including: a processor and a memory storing computer program instructions; the processor reads and executes the computer program instructions to implement the static station cycle slip detection method as described in any of the above embodiments.

[0045] Fourthly, embodiments of this disclosure provide a computer storage medium storing computer program instructions, which, when executed by a processor, implement the static station cycle slip detection method as described in any of the above embodiments.

[0046] The method, apparatus, device, and computer storage medium for static station cycle slip detection in this disclosure can eliminate satellite-to-ground distance by utilizing the known coordinates of the static station during the inter-epoch difference calculation process, thereby reducing the estimated parameters of coordinate changes and avoiding positional deviations; and by performing inter-epoch difference after inter-satellite difference, the influence of residual errors is weakened, which can solve the problem of cycle slip misjudgment and omission when the data sampling rate is low, and can detect small cycle slips, making it highly applicable. Attached Figure Description

[0047] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments of this disclosure will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a flowchart illustrating a method for detecting cycle slip at a static station according to an embodiment of this disclosure;

[0049] Figure 2 This is a flowchart illustrating a specific embodiment of the static station cycle slip detection method disclosed herein;

[0050] Figure 3 This is a flowchart illustrating a specific embodiment of the static station cycle slip detection method disclosed herein;

[0051] Figure 4 This is a flowchart illustrating a method for detecting cycle slip at a static station according to a specific embodiment of this disclosure;

[0052] Figure 5 This is a schematic diagram of the structure of a static station cycle slip detection device provided in an embodiment of this disclosure;

[0053] Figure 6 This is a schematic diagram of the structure of a static station cycle slip detection device in a specific embodiment of the present disclosure;

[0054] Figure 7 This is a schematic diagram of the structure of a static station cycle slip detection device in a specific embodiment of the present disclosure;

[0055] Figure 8 This is a schematic diagram of the structure of a static station cycle slip detection device according to a specific embodiment of this disclosure;

[0056] Figure 9 This is a schematic diagram of the structure of a static station cycle slip detection device provided in an embodiment of this disclosure. Detailed Implementation

[0057] The features and exemplary embodiments of various aspects of this disclosure will now be described in detail. To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description, in conjunction with the accompanying drawings and specific embodiments, will provide a further detailed description. It should be understood that the specific embodiments described herein are intended only to explain this disclosure and not to limit it. For those skilled in the art, this disclosure can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this disclosure by illustrating examples.

[0058] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0059] In applications such as satellite positioning, orbit determination, and satellite clock error calculation, the traditional MW combination method for cycle slip detection, due to the introduction of noisy pseudorange observations, relies heavily on the accuracy of the pseudorange and is generally unable to detect small cycle slips, only suitable for large cycle slips. The GF combination cannot detect insensitive cycle slips. Furthermore, both methods require multiple MW and GF combinations for multi-frequency observations, presenting significant limitations. However, using existing epoch-difference methods for cycle slip detection suffers from significant errors in the inter-epoch difference observations because the ionospheric error, tropospheric error, and hardware delay increase with the sampling interval, and these errors cannot be eliminated through inter-epoch differencing. Moreover, this method typically uses a chi-square test to determine whether a cycle slip has occurred, but the application of the chi-square test has the following problems:

[0060] The test quantity for the chi-square test is:

[0061]

[0062]

[0063] In equation (S2), σ0 represents the unit weight error, which is eliminated in equation (S1). σ represents the unmodeled observation error, including error terms related to orbit, satellite clock error, troposphere, ionosphere, and observation noise. Because the residual error varies significantly depending on the sampling interval, it is difficult to reasonably determine σ using equation (S2), thus hindering accurate weighting and leading to a large error in the calculation of the chi-square test statistic. This results in poor applicability and insensitivity to small cycle slips.

[0064] To address the problems of the prior art, this disclosure provides a method, apparatus, device, and computer storage medium for static station cycle slip detection.

[0065] The method for static station cycle slip detection provided in the embodiments of this disclosure will be described below.

[0066] Figure 1 A flowchart illustrating a method for static station cycle slip detection according to an embodiment of this disclosure is shown. Figure 1 As shown, the method may include the following steps:

[0067] S101. When performing inter-epoch difference based on carrier phase observations, the satellite-to-ground distance in the inter-epoch difference process is eliminated using the known coordinate data of the static station, thus obtaining the first observation equation; the satellite-to-ground distance is the distance from the observation satellite to the ground station.

[0068] S102. Based on the selected reference star, perform the difference calculation between the reference star and the observed satellite based on the first observation equation to obtain the second observation equation;

[0069] S103. Based on the second observation equation, perform inter-epoch difference again to obtain inter-epoch difference observations;

[0070] S104. Based on the interepoch difference observations, determine the cycle slip.

[0071] The method in this embodiment uses carrier phase observations at a single frequency point, enabling detection at each frequency point. It is applicable to single-frequency and multi-frequency detection and has strong scalability. Furthermore, this embodiment gradually eliminates the satellite-to-ground distance between the observation satellite and the static station (i.e., the ground station), eliminates the inter-epoch variation of receiver clock bias at the static station, and reduces the inter-epoch variation of residual errors such as tropospheric errors, ionospheric errors, orbital errors, and satellite clock bias. The final observation is used for cycle slip determination, resulting in minimal error impact. It does not rely on pseudorange observations or require the construction of multiple linear combinations, making it convenient, fast, and highly accurate.

[0072] In this implementation, step S101, when performing inter-epoch difference based on carrier phase observations, eliminates the satellite-to-ground distance during the inter-epoch difference process using known coordinate data from the static station, thus obtaining the first observation equation, as follows: Figure 2As shown, it can specifically include:

[0073] S201. Based on the carrier phase observation values, perform an inter-epoch difference using the pre-constructed inter-epoch differential phase observation equation;

[0074] S202. Calculate the satellite-to-Earth distance value using the known coordinate data of the static station, substitute it into the pre-constructed inter-epoch differential phase observation equation, and obtain the inter-epoch first-order differential equation that eliminates the satellite-to-Earth distance, which serves as the first observation equation.

[0075] For example, the inter-epoch differential phase observation equation pre-constructed using a single frequency point in step S201 is as follows:

[0076]

[0077] Where λ is the carrier wavelength, and Δ is the inter-epoch difference operator. The carrier phase observations are expressed in weeks, where ρ is the satellite-to-Earth distance, c is the speed of light, and t is the carrier phase observation. r Let be the receiver clock bias of the static station, N be the carrier phase ambiguity, ε be the observation noise, and Δε be the epochal variation including multiple errors such as tropospheric error, ionospheric error, orbital error, and satellite clock bias. Here, ρ is the distance from the observation satellite to the ground station.

[0078] Since the coordinates of the ground static station are generally known or can be precisely calculated, in step S202, the interepoch satellite-to-ground distance Δρ can be precisely calculated based on the position of the observed satellite and the coordinates of the ground station. Substituting the obtained satellite-to-ground distance into equation (1) simplifies equation (1), meaning that the interepoch satellite-to-ground distance Δρ, as a known quantity, can be directly eliminated from equation (1), reducing the number of parameters to be estimated. Therefore, the interepoch differential phase observation equation of equation (1), after eliminating the satellite-to-ground distance based on the known coordinates of the static station, yields the interepoch first-order difference equation:

[0079]

[0080] In this embodiment, the first difference equation between epochs in equation (2) is used as the first observation equation. Since the satellite-to-ground distance is eliminated by using the known coordinates of the static station, the coordinate change parameters to be estimated can be reduced throughout the solution process, thereby avoiding the influence of position deviation on cycle slip determination.

[0081] In this embodiment, step S102: Based on the selected reference star, the difference between the reference star and the observed satellite is calculated according to the first observation equation to obtain the second observation equation, as follows. Figure 3 As shown, it can specifically include:

[0082] S301. Select the satellite with the highest elevation angle as the reference satellite;

[0083] S302. Based on the selected reference satellite, perform inter-satellite difference calculations between the reference satellite and the observation satellite using the first-order difference equation between epochs to construct the inter-satellite single-difference observation equation. The inter-satellite single-difference observation equation is obtained by eliminating the relative changes in receiver clock bias between epochs of the static station through inter-satellite difference calculations. The inter-satellite single-difference observation equation serves as the second observation equation.

[0084] Since the inter-epoch variation of receiver clock bias cannot be ignored, it is generally necessary to treat it as a parameter to be estimated in the solution. In this embodiment, the inter-epoch first-order difference equation obtained by eliminating satellite-to-Earth distance can eliminate receiver clock bias through inter-satellite difference. However, if multiple satellites experience cycle slips in the current epoch, the relative inter-epoch variation of receiver clock bias Δt will be significant. r The accuracy of the solution will be affected. Therefore, in this embodiment, the satellite with the highest satellite elevation angle at the current epoch is selected as the reference satellite, because the larger the satellite elevation angle, the less interference it receives. In this embodiment, based on the inter-epoch first-order difference equation, inter-satellite difference calculations are performed on the selected reference satellite and the observed satellite to eliminate the relative changes in receiver clock bias between epochs, resulting in the following inter-satellite single-difference observation equation:

[0085]

[0086] Where i and j represent the reference satellite and the observation satellite, respectively, for inter-satellite difference calculations. λ is the carrier wavelength, and Δ is the inter-epoch difference operator. Let N be the carrier phase observation value in weeks, ε be the carrier phase ambiguity, ε be the observation noise, and Δε be the epochal variation including multiple errors such as tropospheric error, ionospheric error, orbital error, and satellite clock error; then Δε ij This is the residual error term after inter-satellite differentiation, which includes the aforementioned multiple errors.

[0087] Equation (3) serves as the second observation equation. Since it eliminates the relative variation parameters of receiver clock bias between epochs and replaces the conventional least squares estimation solution, it can solve the problem of inaccurate least squares estimation when multiple satellites experience cycle slips.

[0088] In the obtained second observation equation, assuming the observed satellite does not experience a cycle slip, then ΔN ij When the value is 0, only the residual error term Δε remains. ij For high sampling rate data (such as a 1-second sampling rate), the remaining residual error term Δε ij At the millimeter level, when a satellite experiences a cycle slip, the data on the left side of equation (3) will increase significantly. For example, for a GPS (Global Positioning System) L1 carrier, a cycle slip of 1 cycle will result in a change of 0.19m, so small cycle slips can be easily detected.

[0089] For cases with large sampling intervals (e.g., an interval of 30 seconds), the residual error term Δε mentioned above... ij Compared to high sampling rates, the residual error term Δε is larger. ij The residual error can reach the decimeter level. At this point, determining cycle slips based solely on the magnitude of the residual error is prone to misjudgment or underjudgment, especially for small cycle slips like one cycle. To address this issue, this embodiment further refines the residual error term Δε based on the second observation equation. ij To weaken.

[0090] In this embodiment, step S103 involves performing inter-epoch difference again based on the second observation equation to obtain inter-epoch difference observations. Specifically, this includes:

[0091] Based on the second observation equation, a second difference is performed between epochs to obtain the second difference observations between epochs. For example, based on equation (3), the second difference between epochs is performed, and the resulting second difference phase observation equation between epochs is:

[0092]

[0093] Where t and t-1 represent the current epoch and the previous epoch, respectively; λ is the carrier wavelength; and Δ is the inter-epoch difference operator. Let N be the carrier phase observation value in weeks, ε be the carrier phase ambiguity, Δε be the observation noise, and Δε be the epochal variation including multiple errors; then Δε ij (t, t-1) represents the residual error term after the quadratic difference between epochs. The tropospheric error, ionospheric error, etc., are greatly reduced after the quadratic difference between epochs. At this time, the weakened residual error term Δε ij (t, t-1) is basically at the millimeter to centimeter level, which does not affect the determination of the small cycle jump of 1 week; therefore, this embodiment can solve the problem of misjudging the building when the data sampling rate is low, and can detect the small cycle jump.

[0094] In this embodiment, the inter-epoch differential observations are obtained by solving the inter-epoch quadratic differential phase observation equation. The cycle slip determination process, specifically in step S104, includes:

[0095] Based on the inter-epoch difference observations, cycle slips are determined using preset cycle slip determination rules. These rules may include setting a threshold for cycle slip determination; when the absolute value of the inter-epoch difference observation exceeds this threshold, a cycle slip is determined to have occurred.

[0096] For example, the rule for determining cycle slips can be set as follows:

[0097]

[0098] In equation (5), || represents the absolute value, and threshold1 represents the threshold for determining cycle slip.

[0099] In this embodiment, if a cycle slip occurs in the reference satellite, all observations that differ between the current epoch and the reference satellite will become larger, exceeding the threshold for determining a cycle slip. In this case, a new reference satellite can be selected; for example, other satellites with higher elevation angles at the current epoch can be selected as reference satellites.

[0100] In this embodiment, after determining cycle slips based on inter-epoch difference observations, the method further includes:

[0101] After determining that a cycle slip has occurred, a repair determination is made according to the preset repair determination rules.

[0102] For example, the preset repair judgment rule includes: by setting a rounding threshold, when the absolute value of the difference between the inter-epoch difference observation and the rounded value of the inter-epoch difference observation is less than the rounding threshold, the rounded value of the inter-epoch difference observation is used for cycle slip repair.

[0103] In this example, after identifying the observed satellite where the cycle slip occurred, cycle slip repair can be performed based on the residuals. In this embodiment, considering the influence of the residual error term, a fixed rounding method is used for cycle slip repair, that is, the preset repair judgment rule can be:

[0104]

[0105] Where || represents the absolute value, round represents rounding, and threshold2 represents the rounding threshold. When the absolute value of the difference between the inter-epoch difference observation and the rounded value of the inter-epoch difference observation meets the rounding condition, the rounded value of the inter-epoch difference observation is used directly for cycle slip repair.

[0106] Figure 4A specific embodiment of this disclosure is shown. In this embodiment, after constructing the inter-epoch differential phase observation equation in step S401, the satellite-to-Earth distance is solved using known coordinates in step S402 to eliminate the satellite-to-Earth distance parameter in the equation constructed in S401, resulting in the first observation equation. Then, in step S403, the satellite with the highest elevation angle is selected as the reference satellite. In step S404, an inter-satellite single-difference observation equation is constructed based on the first observation equation. Then, in step S405, an inter-epoch second-order differential observation is constructed based on the inter-satellite single-difference observation equation, followed by the cycle slip determination process in step S406. In step S406, if the observation obtained in step S405 is greater than a preset determination threshold, a cycle slip is determined to have occurred; otherwise, the detection ends. If a cycle slip is determined to have occurred in step S406, step S407 is further performed to determine whether the rounded value of the observation obtained in S405 is less than the rounding threshold. If it is, step S408 is performed for cycle slip repair; otherwise, no repair is performed, and the detection ends.

[0107] The method provided in this embodiment is applicable to data preprocessing when using static stations for calculations, such as orbit calculation and satellite clock error calculation in satellite-based systems, and atmospheric error correction calculation in ground-based systems. It uses phase observation values ​​at a single frequency point, and can detect each frequency point. It is applicable to single-frequency and multi-frequency systems, has strong scalability, and provides fast and accurate calculations. In particular, for systems with four or more frequencies, such as Galileo and BDS3, conventional methods require multiple dual-frequency or tri-frequency combinations to detect cycle slips. This disclosure directly detects a single frequency point, has a high detection rate, and can ensure the accuracy of the repair.

[0108] Furthermore, the method disclosed herein is not only applicable to high sampling rates, but also achieves good results at low sampling rates; it can greatly reduce residual errors by constructing inter-satellite differences and inter-epoch quadratic differences, and then directly determine whether cycle slips have occurred through the constructed observations, detect small cycle slips, and easily repair them.

[0109] Figure 5 The diagram shown is a structural schematic of a static station cycle slip detection device provided in an embodiment of this disclosure. Figure 5 The apparatus shown includes:

[0110] The first observation equation acquisition module 501 is used to eliminate the satellite-to-ground distance in the inter-epoch difference process by using the known coordinate data of the static station when performing inter-epoch difference based on the carrier phase observation value, and obtain the first observation equation; the satellite-to-ground distance is the distance from the observation satellite to the ground static station;

[0111] The second observation equation acquisition module 502 is used to perform difference calculation between the reference star and the observed satellite based on the first observation equation according to the selected reference star, so as to obtain the second observation equation.

[0112] The difference module 503 is used to perform inter-epoch difference again based on the second observation equation to obtain inter-epoch difference observations.

[0113] The first determination module 504 is used to determine cycle slips based on interepoch difference observations.

[0114] For example, the first observation equation acquisition module 501 can perform the above... Figure 1 The second observation equation acquisition module 502 can perform the above-described step S101. Figure 1 In step S102 shown above, the differential module 503 can perform the above-described steps. Figure 1 In step S103 shown above, the first determination module 504 can perform the above-described steps. Figure 1 Step S104 is shown in the figure.

[0115] It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module and can achieve its corresponding technical effect. For the sake of brevity, it will not be repeated here.

[0116] For example, such as Figure 6 As shown, the first observation equation acquisition module 501 may specifically include:

[0117] The primary differential module 601 is used to perform inter-epoch primary differential based on the carrier phase observation values ​​and a pre-constructed inter-epoch differential phase observation equation; that is, the primary differential module 601 can perform the above... Figure 2 Step S201 is shown in the figure.

[0118] The calculation elimination module 602 is used to calculate the satellite-to-Earth distance value using known coordinate data from the static station, substitute it into the pre-constructed inter-epoch differential phase observation equation, and obtain the inter-epoch first-order difference equation for eliminating the satellite-to-Earth distance, which serves as the first observation equation. In other words, the calculation elimination module 602 can perform the above... Figure 2 Step S202 is shown in the figure.

[0119] It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module and can achieve its corresponding technical effect. For the sake of brevity, it will not be repeated here.

[0120] For example, such as Figure 7 As shown, the second observation equation acquisition module 502 may specifically include:

[0121] Selection module 701 is used to select the satellite with the highest elevation angle as the reference satellite; that is, selection module 701 can perform the above-mentioned functions. Figure 3 Step S301 is shown in the figure.

[0122] The inter-satellite difference module 702 is used to perform inter-satellite difference calculations between the selected reference satellite and the observing satellite based on the first-order difference equation between epochs, thus constructing an inter-satellite single-difference observation equation. This inter-satellite single-difference observation equation is obtained by eliminating the relative epochal variation of the receiver clock error of the static station through inter-satellite difference calculations. This inter-satellite single-difference observation equation serves as the second observation equation. In other words, the inter-satellite difference module 702 can perform the above... Figure 3 Step S302 is shown in the figure.

[0123] It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module and can achieve its corresponding technical effect. For the sake of brevity, it will not be repeated here.

[0124] In one specific embodiment, such as Figure 8 As shown, in addition to the first observation equation acquisition module 801, the second observation equation acquisition module 802, the difference module 803, and the first determination module 804, the device may also include:

[0125] The second determination module 805 is used to perform a repair determination according to a preset repair determination rule after a cycle slip is determined. The second determination module 805 can perform the above-mentioned... Figure 4 Steps S407 and S408 are shown in the figure.

[0126] It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module and can achieve its corresponding technical effect. For the sake of brevity, it will not be repeated here.

[0127] Figure 9 A hardware structure diagram of a static station cycle slip detection device provided in an embodiment of this disclosure is shown.

[0128] The device for static station cycle slip detection may include a processor 901 and a memory 902 storing computer program instructions.

[0129] Specifically, the processor 901 may include a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits that can be configured to implement the embodiments of this disclosure.

[0130] Memory 902 may include mass storage for data or instructions. For example, and not limitingly, memory 902 may include a hard disk drive (HDD), floppy disk drive, flash memory, optical disk, magneto-optical disk, magnetic tape, or Universal Serial Bus (USB) drive, or a combination of two or more of these. In one instance, memory 902 may include removable or non-removable (or fixed) media, or memory 902 may be non-volatile solid-state memory. Memory 902 may be internal or external to the integrated gateway disaster recovery device.

[0131] Memory 902 may include read-only memory (ROM), random access memory (RAM), disk storage media device, optical storage media device, flash memory device, electrical, optical, or other physical / tangible memory storage device. Therefore, typically, memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the method according to one aspect of this disclosure.

[0132] The processor 901 reads and executes computer program instructions stored in the memory 902 to achieve... Figure 1 The method / steps S101 to S104 in the illustrated embodiment achieve the following: Figure 1 The technical effects achieved by executing the methods / steps shown in the examples are not elaborated here for the sake of brevity.

[0133] In one embodiment, the processor 901 can also achieve [the following] by reading and executing computer program instructions stored in the memory 902. Figure 4 The method / steps S401 to S408 in the illustrated embodiment are completed, and the desired outcome is achieved. Figure 4 The technical effects achieved by executing the methods / steps shown in the examples are not elaborated here for the sake of brevity.

[0134] In one example, the device for static station cycle slip detection may also include a communication interface 903 and a bus 910. For example, Figure 9 As shown, the processor 901, memory 902, and communication interface 903 are connected through bus 910 and complete communication with each other.

[0135] The communication interface 903 is mainly used to realize communication between various modules, devices, units and / or equipment in the embodiments of this disclosure.

[0136] Bus 910 includes hardware, software, or both, that couples components of a static station cycle slip detection device together. For example, and not as a limitation, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Extended Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hyper Transport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an Infinite Bandwidth Interconnect, a Low Pin Count (LPC) bus, a memory bus, a Microchannel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local (VLB) bus, or other suitable buses, or combinations of two or more of these. Where appropriate, bus 910 may include one or more buses. Although specific buses are described and illustrated in embodiments of this disclosure, this disclosure contemplates any suitable bus or interconnect.

[0137] Furthermore, in conjunction with the static station cycle slip detection method in the above embodiments, this disclosure can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when these computer program instructions are executed by a processor, they implement any of the static station cycle slip detection methods in the above embodiments.

[0138] It should be clarified that this disclosure is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of this disclosure is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of this disclosure.

[0139] The functional blocks shown in the above-described block diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this disclosure are programs or code segments used to perform the required tasks. The programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried on a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0140] It should also be noted that the exemplary embodiments mentioned in this disclosure describe methods or systems based on a series of steps or apparatus. However, this disclosure is not limited to the order of the above steps; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0141] The aspects of this disclosure have been described above with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block in the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that these instructions, executable via the processor of the computer or other programmable data processing apparatus, enable the implementation of the functions / actions specified in one or more blocks of the flowchart illustrations and / or block diagrams. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field-programmable logic circuit. It is also understood that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can also be implemented by special-purpose hardware performing the specified functions or actions, or can be implemented by a combination of special-purpose hardware and computer instructions.

[0142] The above description is merely a specific embodiment of this disclosure. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this disclosure is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this disclosure, and these modifications or substitutions should all be covered within the protection scope of this disclosure.

Claims

1. A method for detecting cycle slip at a static station, characterized in that, The method includes: When performing inter-epoch difference based on carrier phase observations, the satellite-to-ground distance in the inter-epoch difference process is eliminated using the known coordinate data of the static station, thus obtaining the first observation equation; the satellite-to-ground distance is the distance from the observation satellite to the ground station. Based on the selected reference star, the difference between the reference star and the observed satellite is calculated based on the first observation equation to obtain the second observation equation; Based on the second observation equation, inter-epoch difference is performed again to obtain inter-epoch difference observations; Cycle slip determination is performed based on the inter-epoch difference observations. The second observation equation is then subjected to inter-epoch difference again to obtain inter-epoch difference observations, including: Based on the second observation equation, a second difference between epochs is performed to obtain the second difference between epochs observations. The equation for the interepochal quadratic difference phase observation is as follows: （1） Where t and t-1 represent the current epoch and the previous epoch, respectively; For carrier wavelength, For epoch difference operators, The carrier phase observations are in weeks. For carrier phase ambiguity, To observe the noise, Let the epochal variation include multiple errors; then This is the residual error term after the second difference between epochs.

2. The method for detecting cycle slip at a static station according to claim 1, characterized in that, When performing inter-epoch difference based on carrier phase observations, the satellite-to-ground distance in the inter-epoch difference process is eliminated using known coordinate data from static stations, resulting in the first observation equation, which includes: Based on the carrier phase observation values, an inter-epoch difference is performed using a pre-constructed inter-epoch differential phase observation equation; The satellite-to-Earth distance is calculated using the known coordinate data of the static station, and then substituted into the pre-constructed inter-epoch differential phase observation equation to obtain an inter-epoch first-order differential equation that eliminates the satellite-to-Earth distance, which serves as the first observation equation.

3. The method for detecting cycle slip at a static station according to claim 2, characterized in that, The pre-constructed inter-epoch differential phase observation equation is as follows: （2） in, For carrier wavelength, For epoch difference operators, The carrier phase observations are in weeks. The distance between the satellite and the Earth is given. At the speed of light, The receiver clock bias of the static station. For carrier phase ambiguity, To observe the noise, This represents the interepochal variation that includes multiple errors; The inter-epoch linear difference equation is obtained by eliminating the satellite-to-Earth distance based on the known coordinates of the static station; the inter-epoch linear difference equation is: （3）。 4. The method for detecting cycle slip at a static station according to claim 2, characterized in that, The step of performing a difference calculation between the selected reference satellite and the observed satellite based on the first observation equation to obtain the second observation equation includes: Select the satellite with the highest elevation angle as the reference satellite; Based on the first difference equation between the epochs, the inter-satellite difference between the reference satellite and the observation satellite is calculated to construct the inter-satellite single difference observation equation; the inter-satellite single difference observation equation is obtained by eliminating the relative change of the receiver clock error between epochs of the static station through the inter-satellite difference calculation; the inter-satellite single difference observation equation serves as the second observation equation.

5. The method for detecting cycle slip at a static station according to claim 4, characterized in that, The inter-satellite single-difference observation equation is as follows: （4）； in, and These respectively represent the reference satellite and the observation satellite used for inter-satellite difference analysis; For carrier wavelength, For epoch difference operators, The carrier phase observations are in weeks. For carrier phase ambiguity, To observe the noise, This represents the interepochal variation that includes multiple errors.

6. The method for detecting cycle slip at a static station according to claim 1, characterized in that, Based on the inter-epoch difference observations, cycle slip determination is performed, including: Based on the inter-epoch difference observations, cycle slips are determined using a preset cycle slip determination rule. The preset cycle slip determination rule includes setting a cycle slip determination threshold. When the absolute value of the inter-epoch difference observations is greater than the determination threshold, a cycle slip is determined to have occurred.

7. The method for static station cycle slip detection according to any one of claims 1-6, characterized in that, After determining cycle slips based on the inter-epoch difference observations, the method further includes: After determining that a cycle slip has occurred, a repair determination is made according to the preset repair determination rules.

8. The method for detecting cycle slip at a static station according to claim 7, characterized in that, The preset repair judgment rule includes: by setting a rounding threshold, when the absolute value of the difference between the inter-epoch difference observation and the rounded value of the inter-epoch difference observation is less than the rounding threshold, the rounded value of the inter-epoch difference observation is taken for cycle slip repair.

9. A device for detecting cycle slip at a static station, characterized in that, The device includes: The first observation equation acquisition module is used to eliminate the satellite-to-ground distance in the inter-epoch difference process by using the known coordinate data of the static station when performing inter-epoch difference based on the carrier phase observation value, and obtain the first observation equation; the satellite-to-ground distance is the distance from the observation satellite to the ground static station; The second observation equation acquisition module is used to perform difference calculation between the selected reference star and the observed satellite based on the first observation equation to obtain the second observation equation. The difference module is used to perform inter-epoch difference again based on the second observation equation to obtain inter-epoch difference observations; The first determination module is used to determine cycle slips based on the interepoch difference observations. Specifically, the differential module includes: Based on the second observation equation, a second difference between epochs is performed to obtain the second difference between epochs observations. The equation for the interepochal quadratic difference phase observation is as follows: （1） Where t and t-1 represent the current epoch and the previous epoch, respectively; For carrier wavelength, For epoch difference operators, The carrier phase observations are in weeks. For carrier phase ambiguity, To observe the noise, Let the epochal variation include multiple errors; then This is the residual error term after the second difference between epochs.

10. The cycle slip detection device according to claim 9, characterized in that, The device further includes: The second determination module is used to perform repair determination according to preset repair determination rules after a cycle slip is determined.

11. A device for detecting cycle slip at a static station, characterized in that, The device includes: a processor and a memory storing computer program instructions; the processor reads and executes the computer program instructions to implement the static station cycle slip detection method as described in any one of claims 1-8.

12. A computer storage medium, characterized in that, The computer storage medium stores computer program instructions, which, when executed by a processor, implement the static station cycle slip detection method as described in any one of claims 1-8.

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