Method, device, system and storage medium for fixing integer ambiguities

Abstract

Embodiments of the present application provide a method, device, system and storage medium for fixing integer ambiguity, which comprises determining a first single-difference wide-lane float ambiguity of a target satellite at a current time according to observation data at the current time, correcting the first single-difference wide-lane float ambiguity according to a single-difference trend item error corresponding to the first single-difference wide-lane float ambiguity, and determining a double-difference wide-lane integer ambiguity at the current time according to the corrected first single-difference wide-lane float ambiguity. The method for fixing integer ambiguity provided by the embodiments of the present application can accurately extract multipath errors by introducing receiver code phase bias estimation, so that all satellites can use inter-station single-difference mode to obtain more accurate double-difference wide-lane integer ambiguity, which not only solves the problem of unified processing of different types of satellites, improves the data processing efficiency, but also improves the fixing rate of the wide-lane integer ambiguity of each satellite to a certain extent.

Description

Technical Field

[0001] This application relates to the field of satellite navigation technology, and in particular to a method, device, system, and storage medium for fixing integer ambiguity. Background Technology

[0002] In navigation and positioning using a Global Navigation Satellite System (GNSS), accurately calculating the integer ambiguity of the carrier phase is a crucial prerequisite for ensuring navigation and positioning accuracy. Related technologies typically fix the wide-lane integer ambiguity first, and then fix the ambiguity of individual frequency points. However, due to multipath effects, the accuracy of the wide-lane integer ambiguity is relatively low.

[0003] In related technologies, the wide-lane floating-point ambiguity obtained by the MW combination method is usually smoothed for a period of time, and then the double-difference wide-lane integer ambiguity is fixed by rounding to the nearest integer. Based on the fixed double-difference wide-lane integer ambiguity, multipath error is separated from the previous period data.

[0004] However, in the process of realizing this application, the inventors discovered that the prior art has at least the following problems: the above-mentioned method of separating multipath errors is affected by factors such as reference star transformation and cycle slip, and satellites with different orbit repetition periods in the same satellite navigation system cannot be processed uniformly, resulting in low data processing efficiency. Summary of the Invention

[0005] This application provides a method, device, system, and storage medium for fixing integer ambiguity, enabling unified processing of different types of satellites and improving data processing efficiency.

[0006] In a first aspect, embodiments of this application provide a method for fixing integer ambiguity, comprising:

[0007] Based on the observation data at the current moment, determine the first single-difference wide-lane floating-point ambiguity of the target satellite at the current moment;

[0008] The single-difference trend term error corresponding to the previous time point is obtained; the difference between the previous time point and the current time point is related to the orbital repetition period of the target satellite; the single-difference trend term error is determined based on the second single-difference wide-lane floating-point ambiguity of the target satellite at the previous time point and the corresponding receiver endcode phase deviation; the second single-difference wide-lane floating-point ambiguity is determined based on the observation data at the previous time point;

[0009] The first single-difference wide-lane floating-point ambiguity is corrected based on the single-difference trend term error corresponding to the first single-difference wide-lane floating-point ambiguity to obtain the corrected first single-difference wide-lane floating-point ambiguity.

[0010] Based on the corrected first single-difference wide-lane floating-point ambiguity, the double-difference wide-lane integer ambiguity at the current moment is determined.

[0011] In one possible design, obtaining the single-difference trend term error corresponding to the previous time step includes:

[0012] Based on the current time, the orbital repetition period of the target satellite, and the corresponding lead time, determine the previous time corresponding to the current time;

[0013] Based on the previous time and the first correspondence, the single difference trend term error corresponding to the previous time is determined from a plurality of pre-stored single difference trend term errors; the first correspondence includes a plurality of single difference trend term errors and a correspondence between a plurality of time.

[0014] In one possible design, before obtaining the single-difference trend term error corresponding to the previous time step, the following steps are also included:

[0015] Acquire observation data from multiple satellites within the reference time period of the previous time; among the multiple satellites is a target satellite, which belongs to a target navigation system;

[0016] Calculate the receiver endcode phase deviation at the previous time point based on observation data from multiple satellites;

[0017] Based on the receiver endcode phase deviation, determine the single-difference wide-lane integer ambiguity of the target satellite at the previous time.

[0018] Based on the single-difference wide-lane integer ambiguity, the error of the single-difference trend term corresponding to the previous time step is determined.

[0019] In one possible design, calculating the receiver endcode phase deviation at the previous time point based on observation data from multiple satellites includes:

[0020] Based on a preset duration, the reference time period is divided into multiple time intervals; the preset duration is related to the stability period of the code phase deviation.

[0021] For each continuous arc segment that meets the preset conditions in each time interval, based on the observation data of multiple non-GEO satellites in the target navigation system corresponding to the continuous arc segment, multiple second single-difference wide-lane floating-point ambiguities corresponding to the continuous arc segment are calculated, and the first mean value of the multiple second single-difference wide-lane floating-point ambiguities corresponding to the continuous arc segment is determined.

[0022] For each time interval, the fractional part corresponding to the multiple first averages is extracted, and the receiver endcode phase deviation of the time interval is determined based on the multiple fractional parts.

[0023] In one possible design, determining the single-difference wide-lane integer ambiguity of the target satellite at the previous time point based on the receiver endcode phase deviation includes:

[0024] Based on the observation data of the target satellite corresponding to the continuous time period of the target, calculate multiple second single-difference wide-lane floating-point ambiguities corresponding to the continuous time period of the target;

[0025] For each of the multiple second single-difference wide-lane floating-point ambiguities corresponding to the target continuous time period, a second difference is calculated between the second single-difference wide-lane floating-point ambiguity and the corresponding receiver endcode phase deviation; the target continuous arc segment includes the previous time period;

[0026] Calculate the second mean of multiple second differences, and round the second difference to the nearest integer to obtain the single-difference wide-lane integer ambiguity corresponding to the continuous arc segment of the target. Then, determine the single-difference wide-lane integer ambiguity corresponding to the continuous arc segment of the target as the single-difference wide-lane integer ambiguity of the target satellite at the previous time.

[0027] In one possible design, determining the single-difference trend term error corresponding to the previous time step based on the single-difference wide-lane integer ambiguity includes:

[0028] Calculate the first difference between the second single-difference wide-lane floating-point ambiguity and the single-difference wide-lane integer ambiguity of the target satellite at the previous time.

[0029] The first difference is denoised to obtain the single difference trend term error corresponding to the previous time point.

[0030] In one possible design, determining the double-difference wide-lane integer ambiguity at the current moment based on the corrected first single-difference wide-lane floating-point ambiguity includes:

[0031] The difference between the corrected first single-difference wide-lane floating-point ambiguity and the third single-difference wide-lane floating-point ambiguity of the reference star corresponding to the target satellite is determined as the double-difference wide-lane floating-point ambiguity of the target satellite.

[0032] The floating-point ambiguity of the double-difference wide-lane is smoothed and rounded in real time to obtain the integer ambiguity of the double-difference wide-lane.

[0033] Secondly, embodiments of this application provide a device for fixing integer ambiguity, comprising:

[0034] The determination module is used to determine the first single-difference wide-lane floating-point ambiguity of the target satellite at the current moment based on the observation data at the current moment;

[0035] The acquisition module acquires the single-difference trend term error corresponding to the previous time; the difference between the previous time and the current time is related to the orbital repetition period of the target satellite; the single-difference trend term error is determined based on the second single-difference wide-lane floating-point ambiguity of the target satellite at the previous time and the corresponding receiver endcode phase deviation; the second single-difference wide-lane floating-point ambiguity is determined based on the observation data at the previous time.

[0036] The correction module is used to correct the first single-difference wide-lane floating-point ambiguity based on the single-difference trend term error corresponding to the first single-difference wide-lane floating-point ambiguity, so as to obtain the corrected first single-difference wide-lane floating-point ambiguity.

[0037] The processing module is used to determine the double-difference wide-lane integer ambiguity at the current moment based on the corrected first single-difference wide-lane floating-point ambiguity.

[0038] Thirdly, embodiments of this application provide a device for fixing integer ambiguity, comprising: at least one processor and a memory;

[0039] The memory stores computer-executed instructions;

[0040] The at least one processor executes computer execution instructions stored in the memory, causing the at least one processor to perform the method described in the first aspect above and various possible designs of the first aspect.

[0041] Fourthly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the method described in the first aspect and various possible designs of the first aspect.

[0042] Fifthly, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the method described in the first aspect and various possible designs of the first aspect.

[0043] Sixthly, embodiments of this application provide a positioning service system, including multiple base stations, a data processing center, and terminal devices;

[0044] The reference station is used to acquire observation data from multiple satellites and send the observation data to the data processing center.

[0045] The data processing center is used to perform baseline calculations between reference stations based on observation data, and to perform overall modeling and calculation based on the baseline calculation results to obtain an error model. Based on the error model, a virtual reference station is established for the terminal equipment.

[0046] The data processing center performs baseline calculations between reference stations based on the observation data, specifically to implement the methods described in the first aspect and various possible designs of the first aspect.

[0047] This embodiment provides a method, device, system, and storage medium for fixing integer ambiguity. The method first determines the first single-difference wide-lane floating-point ambiguity of the target satellite at the current moment based on observation data. Then, it obtains the single-difference trend term error corresponding to a previous moment. The difference between the previous moment and the current moment is related to the orbital repetition period of the target satellite. The single-difference trend term error is determined based on the second single-difference wide-lane floating-point ambiguity of the target satellite at the previous moment and the corresponding receiver endcode phase deviation. The second single-difference wide-lane floating-point ambiguity is determined based on the observation data at the previous moment. Next, the first single-difference wide-lane floating-point ambiguity is corrected based on the single-difference trend term error corresponding to the first single-difference wide-lane floating-point ambiguity to obtain a corrected first single-difference wide-lane floating-point ambiguity. Finally, the double-difference wide-lane integer ambiguity at the current moment is determined based on the corrected first single-difference wide-lane floating-point ambiguity. The integer ambiguity fixing method provided in this application introduces receiver endcode phase deviation estimation and determines the single-difference trend term error based on the receiver endcode phase deviation. This accurately extracts multipath errors, allowing all satellites to use an inter-station single-difference method. By correcting the single-difference trend term error, more accurate double-difference wide-lane integer ambiguities can be calculated. This solves the problem of unified processing for different types of satellites, improves data processing efficiency, and also increases the fixing rate of wide-lane integer ambiguities for each satellite to a certain extent. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 An application scenario diagram illustrating the integer ambiguity fixing method provided in the embodiments of this application;

[0050] Figure 2 Flowchart of the method for fixing integer ambiguity provided in the embodiments of this application Figure 1 ;

[0051] Figure 3 Flowchart of the method for fixing integer ambiguity provided in the embodiments of this application Figure 2 ;

[0052] Figure 4 A flowchart illustrating step 302 provided in an embodiment of this application;

[0053] Figure 5 This is a flowchart illustrating step 303 provided in an embodiment of this application;

[0054] Figure 6 A schematic diagram of the structure of the device for fixing integer ambiguity provided in an embodiment of this application;

[0055] Figure 7 A structural block diagram of a device for fixing integer ambiguity provided in an embodiment of this application. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0057] A Global Navigation Satellite System (GNSS) consists of multiple satellites orbiting the Earth, which work together to provide positioning services to terminal devices located on the Earth's surface. These terminal devices can determine their latitude, longitude, elevation, and other positioning data by receiving positioning signals from multiple satellites in orbit. For example, in some satellite positioning systems, a terminal device can receive positioning signals from four or eight satellites at a given moment, and then use these signals to determine its location at that specific instant.

[0058] In practical implementations, GNSS can include: Global Positioning System (GPS), Galileo system, and BeiDou Navigation Satellite System (BDS). BeiDou Navigation Satellite System further includes Medium Earth Orbit (MEO) satellites, Geostationary Orbit (GEO) satellites, and Inclined Geosynchronous Orbit (IGSO) satellites.

[0059] Terminal devices that can enjoy the positioning services provided by GNSS can also be called terminals. Terminal devices can be user equipment (UE), mobile station (MS), mobile terminal (MT), etc. Terminal devices can also be mobile phones, tablets, computers with wireless transceiver capabilities, virtual reality (VR) terminal devices, augmented reality (AR) terminal devices, wireless terminal devices in industrial control, wireless terminal devices in self-driving, wireless terminal devices in remote medical surgery, wireless terminal devices in smart grids, wireless terminal devices in transportation safety, wireless terminal devices in smart cities, wireless terminal devices in smart homes, etc.

[0060] In a specific application, a Virtual Reference Station (VRS) is a network real-time dynamic differential (RTK) positioning system technology that integrates Internet technology, wireless communication technology, computer network management technology, and GNSS technology. Figure 1 This diagram illustrates an application scenario for the integer ambiguity fixing method provided in this application's embodiments. For example... Figure 1 As shown, the VRS system includes a reference station network, a data processing center 101, and terminal equipment 102. The reference station network includes multiple reference stations 103, used to acquire observation data from multiple satellites and send the observation data to the data processing center. The data processing center is used to perform baseline calculations between reference stations based on the observation data, and to perform overall modeling and calculations based on the baseline calculation results, thereby establishing virtual reference stations for the terminal equipment, realizing real-time RTK, and providing navigation and positioning services for the terminal equipment.

[0061] In the specific implementation process, the data processing center 101 continuously performs baseline calculations based on the real-time observation data collected by each reference station 103, and then performs overall modeling and calculations in the region based on the results of the baseline calculations. By establishing accurate error models (such as error models of the ionosphere, troposphere, and satellite orbit), a virtual reference station (VRS) that does not exist physically is generated near the mobile station (terminal device 102). Since the position of the virtual reference station is determined by the single-point positioning solution of the mobile station receiver, the baseline formed by it and the mobile station is usually only a few meters to a dozen meters. The mobile station and the virtual reference station perform carrier phase differential correction to achieve real-time RTK.

[0062] In the baseline resolution process described above, the Melbourne-Wubeen acromion (MW) method is typically used to fix the wide-lane integer ambiguity. Then, the IF combined ambiguity and the fixed wide-lane ambiguity are used to determine the ambiguity at a single frequency point. When fixing the wide-lane integer ambiguity using the MW method, the wide-lane integer ambiguity is usually obtained by smoothing the floating-point ambiguity obtained from the MW combination over a period of time and then rounding it to the nearest integer. Considering the influence of pseudorange multipath effects, one approach in the related techniques is to use a moving average method to calculate and subtract the pseudorange multipath effects in the baseline resolution. Another approach is to use a sidereal-day filtering method, which is a method that uses the daily repeatability of satellite constellations to separate and reduce multipath errors. Specifically, it separates multipath errors from the previous period's data based on a fixed double-difference ambiguity. However, the method of smoothing and rounding the floating-point ambiguity obtained by MW combination after a period of time cannot reduce the impact of pseudorange error by smoothing when there is a large trend term error in the pseudorange, such as when it is significantly affected by multipath. The method of using moving average to deal with the multipath effect is affected by the low-frequency component of pseudorange error. When the pseudorange contains low-frequency components with large amplitude, it is difficult to accurately remove the deviation value in multipath through short-term averaging. On the other hand, setting the averaging time too long will affect the continuity and reliability of the solution during the smoothing period. The traditional method of separating multipath based on fixed double difference ambiguity is affected by factors such as reference star transformation and cycle slip. It cannot uniformly handle satellites with different orbit repetition periods in the same satellite navigation system (such as MEO satellites and GEO and IGSO satellites in the Beidou system).

[0063] To address the aforementioned technical problems, the inventors of this application have discovered that, to avoid the influence of factors such as reference star transformation and to be applicable to all types of satellites, inter-station single-difference wide-lane integer ambiguity can be fixed to accurately extract inter-station single-difference multipath. Furthermore, considering that code and phase deviations at the receiver end disrupt the integer characteristics of single-difference ambiguity, the wide-lane integer ambiguity can be fixed by estimating the receiver-end code and phase deviations and then subtracting these deviation values ​​from the wide-lane floating-point ambiguity, thereby accurately extracting multipath. This solves the problem of uniform processing for different types of satellites and also improves the fixation rate of wide-lane integer ambiguity for each satellite to a certain extent. Based on this, embodiments of this application provide a method for fixing integer ambiguity.

[0064] based on Figure 1 In the application scenario shown, when fixing the wide-lane ambiguity using the MW combination method in baseline resolution, the data processing center first determines the first single-difference wide-lane floating-point ambiguity of the target satellite at the current moment based on the observation data at the current moment. Next, it obtains the single-difference trend term error corresponding to the previous moment. The difference between the previous moment and the current moment is related to the orbital repetition period of the target satellite. The single-difference trend term error is determined based on the second single-difference wide-lane floating-point ambiguity of the target satellite at the previous moment and the corresponding receiver endcode phase deviation. The second single-difference wide-lane floating-point ambiguity is determined based on the observation data at the previous moment. Then, the first single-difference wide-lane floating-point ambiguity is corrected based on the single-difference trend term error corresponding to the first single-difference wide-lane floating-point ambiguity to obtain the corrected first single-difference wide-lane floating-point ambiguity. Finally, the double-difference wide-lane integer ambiguity at the current moment is determined based on the corrected first single-difference wide-lane floating-point ambiguity.

[0065] The integer ambiguity fixing method provided in this application introduces receiver endcode phase deviation estimation and determines the single-difference trend term error based on the receiver endcode phase deviation. This accurately extracts multipath errors, allowing all satellites to use an inter-station single-difference method. By correcting the single-difference trend term error, more accurate double-difference wide-lane integer ambiguities can be calculated. This solves the problem of unified processing for different types of satellites and also improves the fixing rate of wide-lane integer ambiguities for each satellite to a certain extent.

[0066] It should be noted that, Figure 1 The schematic diagram shown is merely an example. The method and scenario for fixing integer ambiguity described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of the system and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0067] The technical solutions of this application will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0068] Figure 2 Flowchart of the method for fixing integer ambiguity provided in the embodiments of this application Figure 1 .like Figure 2 As shown, the method includes:

[0069] 201. Based on the observation data at the current moment, determine the first single-difference wide-lane floating-point ambiguity of the target satellite at the current moment.

[0070] The execution subject in this embodiment can be an electronic device with data processing capabilities, such as... Figure 1 The data processing center shown.

[0071] In this embodiment, the observation data refers to the observation data of the target satellite, which may include carrier phase observations L1 and pseudorange observations P1 at the L1 frequency point, and carrier phase observations L2 and pseudorange observations P2 at the L2 frequency point. The first single-difference wide-lane floating-point ambiguity can be the ambiguity calculated using the MW combination method.

[0072] Specifically, in calculating the first single-difference wide-lane floating-point ambiguity of the target satellite at the current moment... When this is the case, the following expression can be used:

[0073]

[0074] Where, λ wl Let f1 and f2 be the wavelengths of the wide-lane combination, and f1 and f2 be the frequencies of the two points of the wide-lane combination. and For carrier phase observations at two frequency points, P1 s and These are pseudorange observations at two frequency points.

[0075] 202. Obtain the single-difference trend term error corresponding to the previous time; the difference between the previous time and the current time is related to the orbital repetition period of the target satellite; the single-difference trend term error is determined based on the second single-difference wide-lane floating-point ambiguity of the target satellite at the previous time and the corresponding receiver endcode phase deviation; the second single-difference wide-lane floating-point ambiguity is determined based on the observation data at the previous time.

[0076] In this embodiment, the target satellite has an orbital repetition period. The previous time can be any time in the period before the current time, and the orbital position of the target satellite at the previous time is the same as its orbital position at the current time.

[0077] In this embodiment, the single-difference trend term error can be a multipath error. For single-difference observations, only inter-station differential is performed. The single-difference wide-lane floating-point ambiguity still retains the receiver-side code phase deviation, which is not eliminated. The code phase deviation disrupts the integer characteristic of the single-difference wide-lane floating-point ambiguity. Therefore, the composition of the single-difference wide-lane floating-point ambiguity includes part of the single-difference wide-lane integer ambiguity, part of the receiver-side code phase deviation, and part of the error. Among them, the error can be smoothed out by averaging. By estimating the code phase deviation, the accurate integer ambiguity can be obtained. After obtaining the integer ambiguity, the single-difference wide-lane integer ambiguity can be subtracted from the single-difference wide-lane floating-point ambiguity to accurately extract the multipath error and obtain the single-difference trend term error.

[0078] In some embodiments, the single-difference trend term error corresponding to the previous time step can be calculated in real time or pre-calculated and stored in storage. Furthermore, the single-difference trend term error can be calculated by a data processing center or by other devices; this embodiment does not limit this.

[0079] In some embodiments, to improve computational efficiency, the acquisition of the single-difference trend term error corresponding to the previous time can be pre-set, which may include: determining the previous time corresponding to the current time based on the current time, the orbital repetition period of the target satellite and the corresponding lead; determining the single-difference trend term error corresponding to the previous time from a plurality of pre-stored single-difference trend term errors based on the previous time and a first correspondence relationship; the first correspondence relationship includes the correspondence relationship between a plurality of single-difference trend term errors and a plurality of times.

[0080] For example, the orbital repetition period of MEO satellite s in the BDS system is 7 days and the lead time is 1715s. Then, for satellite s, the trend term error value at time t should be (t-86400*7+1715).

[0081] 203. Correct the first single-difference wide-lane floating-point ambiguity according to the single-difference trend term error corresponding to the first single-difference wide-lane floating-point ambiguity to obtain the corrected first single-difference wide-lane floating-point ambiguity.

[0082] Specifically, the corrected first single-difference wide-lane floating-point ambiguity can be calculated based on the following expression:

[0083]

[0084] in, For the corrected first single-difference wide-lane floating-point ambiguity, For the error of the single-difference trend term, The first single-difference wide-lane floating-point ambiguity.

[0085] 204. Determine the double-difference wide-lane integer ambiguity at the current moment based on the corrected first single-difference wide-lane floating-point ambiguity.

[0086] Specifically, after obtaining the corrected first single-difference wide-lane floating-point ambiguity, the double-difference wide-lane floating-point ambiguity can be further calculated, and then the double-difference wide-lane integer ambiguity at the current moment can be obtained by smoothing and rounding.

[0087] In some embodiments, to improve the real-time performance of integer ambiguity resolution, determining the double-difference wide-lane integer ambiguity at the current moment based on the corrected first single-difference wide-lane floating-point ambiguity may include: determining the difference between the corrected first single-difference wide-lane floating-point ambiguity and the third single-difference wide-lane floating-point ambiguity of the reference satellite corresponding to the target satellite as the double-difference wide-lane floating-point ambiguity of the target satellite; and performing real-time smoothing and rounding on the double-difference wide-lane floating-point ambiguity to obtain the double-difference wide-lane integer ambiguity.

[0088] Specifically, the double-difference wide-lane floating-point ambiguity can be calculated based on the following expression.

[0089]

[0090] Among them, s j As the reference star, For the corrected first single-difference wide-lane floating-point ambiguity, The third single-difference wide-lane floating-point ambiguity of the reference star.

[0091] The integer ambiguity fixing method provided in this embodiment introduces receiver endcode phase deviation estimation and determines the single-difference trend term error based on the receiver endcode phase deviation. This accurately extracts multipath errors, allowing all satellites to use an inter-station single-difference method. By correcting the single-difference trend term error, more accurate double-difference wide-lane integer ambiguities can be calculated. This solves the problem of unified processing for different types of satellites and also improves the fixing rate of wide-lane integer ambiguities for each satellite to a certain extent.

[0092] Figure 3 Flowchart of the method for fixing integer ambiguity provided in the embodiments of this application Figure 2 .like Figure 3 As shown, based on the above embodiments, for example in Figure 2 Based on the illustrated embodiment, this embodiment provides a detailed explanation of the method for determining the error of the single-difference trend term. This method includes:

[0093] 301. Obtain observation data of multiple satellites within the reference time period of the previous time; among the multiple satellites is a target satellite, which belongs to a target navigation system.

[0094] Specifically, the reference period can be the reference date of a previous time. Reference data is satellite observation data obtained during the reference period. Multiple satellites can belong to the same navigation system or different navigation systems.

[0095] In some embodiments, since the base station can observe multiple satellites, the single difference trend terms of multiple satellites can be calculated in parallel to improve computational efficiency.

[0096] For example, reference date data corresponding to the observed date data can be found based on the orbital repetition period of different satellites in different systems.

[0097] 302. Calculate the receiver endcode phase deviation at the previous time based on the observation data from the multiple satellites.

[0098] Specifically, for each of the multiple satellites, the second single-difference wide-lane floating-point ambiguity at multiple moments within the reference time period can be calculated to obtain a first sequence. Specifically, for each satellite, multiple instantaneous values ​​within the reference time period are calculated, i.e., multiple second single-difference wide-lane floating-point ambiguities. Each satellite corresponds to one first sequence. Thus, multiple first sequences of satellites are obtained, serving as the basis data for subsequent steps. Based on the multiple first sequences, the receiver endcode phase deviation of the target satellite at the previous moment is determined.

[0099] For example, the MW method can be used to calculate the combined value of the instantaneous inter-station single difference MW on the reference day based on formula (1). That is, the second single-difference wide-lane floating-point ambiguity.

[0100] In some embodiments, such as Figure 4 As shown, step 302 can specifically include:

[0101] 3021. Based on a preset duration, the reference time period is divided into multiple time intervals; the preset duration is related to the stable period of the code phase deviation.

[0102] 3022. For each continuous arc segment that meets the preset conditions in each time interval, based on the observation data of multiple non-GEO satellites in the target navigation system corresponding to the continuous arc segment, calculate multiple second single-difference wide-lane floating-point ambiguities corresponding to the continuous arc segment, and determine the first mean value of the multiple second single-difference wide-lane floating-point ambiguities corresponding to the continuous arc segment.

[0103] 3023. For each time interval, extract the fractional part corresponding to the multiple first averages respectively, and determine the receiver endcode phase deviation of the time interval based on the multiple fractional parts.

[0104] For example, the first mean of multiple second single-difference wide-lane floating-point ambiguities for all continuous arc segments of all satellites within each time interval is calculated sequentially, i.e., the single-difference MW combined mean.

[0105] To improve the accuracy of code phase deviation, continuous arc segments can be filtered based on preset conditions. The preset conditions can set elevation angle thresholds and conditions that the shortest arc segment length must meet, such as setting the elevation angle to be greater than 30° and the arc segment length to be no less than 1 hour.

[0106] After obtaining the mean of the single-difference MW combination for each continuous arc segment that meets the conditions, the fractional part of the mean of the MW combination of all satellites of each navigation system can be taken sequentially, that is, the fractional part of the first mean, denoted as .

[0107] In some embodiments, to improve the accuracy of calculations, a one-week flip problem can be addressed for the fractional part. The one-week flip problem refers to the following: the receiver endcode phase deviation is the same for all satellites. If the difference in the fractional parts of different satellites is close to 1, for example, the fractional parts of two satellites are located near 0.1 and -0.9 respectively, then an operation of adding or subtracting 1 is performed to adjust the fractional part deviation values ​​of all satellites to within 0.5 weeks.

[0108] After obtaining the decimal part corresponding to the first mean Then, the fractional part of the first mean of all non-GEO satellites for each navigation system is averaged to obtain the receiver endcode phase bias. This can be expressed using the following formula.

[0109]

[0110] 303. Based on the receiver endcode phase deviation, determine the single-difference wide-lane integer ambiguity of the target satellite at the previous time.

[0111] In some embodiments, such as Figure 5 As shown, step 303 can specifically include:

[0112] 3031. Based on the observation data of the target satellite corresponding to the continuous time period of the target, calculate multiple second single-difference wide-lane floating-point ambiguities corresponding to the continuous time period of the target.

[0113] 3032. For each of the multiple second single-difference wide-lane floating-point ambiguities corresponding to the target continuous time period, calculate the second difference between the second single-difference wide-lane floating-point ambiguity and the corresponding receiver endcode phase deviation; the target continuous arc segment includes the previous time period.

[0114] 3033. Calculate the second mean of multiple second differences, and round the second difference to the nearest integer to obtain the single-difference wide-lane integer ambiguity corresponding to the continuous arc segment of the target, and determine the single-difference wide-lane integer ambiguity corresponding to the continuous arc segment of the target as the single-difference wide-lane integer ambiguity of the target satellite at the previous time.

[0115] For example, from the combined MW value of each satellite After removing the bias, calculate the mean of the single-difference MW combination values ​​for all continuous arc segments of the satellites after removing the bias.

[0116] It should be noted that in the receiver endcode phase deviation calculation, the mean value is calculated for continuous arc segments within the interval, while the interval can be ignored for continuous arc segments in this step. For continuous arc segments that span at least two intervals, the meaning of continuous arc segments in the two steps can be different.

[0117] For each continuous arc segment of each satellite, the integer ambiguity of the single-difference wide-lane is determined based on the following expression, taking the nearest integer value of the MW combination after deducting the deviation value.

[0118]

[0119] For each satellite, based on the following expression, the wide lane integer ambiguity is subtracted from the single-difference MW combination to obtain the single-difference trend term error sequence for each satellite.

[0120]

[0121] 304. Based on the single-difference wide-lane integer ambiguity, determine the single-difference trend term error corresponding to the previous time step.

[0122] In some embodiments, determining the single-difference trend term error corresponding to the previous time based on the first difference between the second single-difference wide-lane floating-point ambiguity and the single-difference wide-lane integer ambiguity of the target satellite at the previous time may include: calculating the first difference between the second single-difference wide-lane floating-point ambiguity and the single-difference wide-lane integer ambiguity of the target satellite at the previous time; and performing denoising processing on the first difference to obtain the single-difference trend term error corresponding to the previous time.

[0123] For example, a low-pass filter can be used to denoise the trend term error, resulting in a denoised single-difference wide-lane floating-point ambiguity trend term error sequence.

[0124] 305. Based on the observation data at the current moment, determine the first single-difference wide-lane floating-point ambiguity of the target satellite at the current moment.

[0125] 306. Obtain the error of the single difference trend term corresponding to the previous time step.

[0126] 307. Correct the first single-difference wide-lane floating-point ambiguity according to the single-difference trend term error corresponding to the first single-difference wide-lane floating-point ambiguity to obtain the corrected first single-difference wide-lane floating-point ambiguity.

[0127] 308. Determine the double-difference wide-lane integer ambiguity at the current moment based on the corrected first single-difference wide-lane floating-point ambiguity.

[0128] In this embodiment, steps 305 to 308 are similar to steps 201 to 204 in the above embodiment, and will not be described again here.

[0129] The integer ambiguity fixing method provided in this embodiment introduces receiver endcode phase deviation estimation and determines the single-difference trend term error based on the receiver endcode phase deviation. This accurately extracts multipath errors, allowing all satellites to use an inter-station single-difference method. By correcting the single-difference trend term error, more accurate double-difference wide-lane integer ambiguities can be calculated. This solves the problem of unified processing for different types of satellites and also improves the fixing rate of wide-lane integer ambiguities for each satellite to a certain extent.

[0130] Figure 6 A schematic diagram of the structure of the integer ambiguity fixing device provided in an embodiment of this application. (See attached diagram.) Figure 6 As shown, the fixed device 60 for integer ambiguity includes: a determination module 601, an acquisition module 602, a correction module 603, and a processing module 604.

[0131] The determination module 601 is used to determine the first single-difference wide-lane floating-point ambiguity of the target satellite at the current time based on the observation data at the current time.

[0132] The acquisition module 602 acquires the single-difference trend term error corresponding to the previous time; the difference between the previous time and the current time is related to the orbital repetition period of the target satellite; the single-difference trend term error is determined based on the second single-difference wide-lane floating-point ambiguity of the target satellite at the previous time and the corresponding receiver endcode phase deviation; the second single-difference wide-lane floating-point ambiguity is determined based on the observation data at the previous time.

[0133] The correction module 603 is used to correct the first single-difference wide-lane floating-point ambiguity based on the single-difference trend term error corresponding to the first single-difference wide-lane floating-point ambiguity, so as to obtain the corrected first single-difference wide-lane floating-point ambiguity.

[0134] The processing module 604 is used to determine the double-difference wide-lane integer ambiguity at the current moment based on the corrected first single-difference wide-lane floating-point ambiguity.

[0135] The integer ambiguity fixing device provided in this application introduces receiver endcode phase deviation estimation and determines the single-difference trend term error based on the receiver endcode phase deviation. This enables accurate extraction of multipath errors, allowing all satellites to use an inter-station single-difference method. By correcting the single-difference trend term error, more accurate double-difference wide-lane integer ambiguities can be calculated. This solves the problem of unified processing for different types of satellites and also improves the fixing rate of wide-lane integer ambiguities for each satellite to a certain extent.

[0136] The integer ambiguity fixing device provided in this application embodiment can be used to execute the above method embodiment. Its implementation principle and technical effect are similar, and will not be repeated here.

[0137] Figure 7 This is a structural block diagram of a device for fixing integer ambiguity provided in an embodiment of this application. The device can be a data processing device such as a computer or server.

[0138] The device 70 may include one or more of the following components: a processing component 701, a memory 702, a power supply component 703, an input / output (I / O) interface 706, a sensor component 707, and a communication component 705.

[0139] Processing component 701 typically controls the overall operation of device 70, such as operations associated with display, telephone calls, data communication, camera operation, and recording. Processing component 701 may include one or more processors 704 to execute instructions to perform all or part of the steps of the methods described above. Furthermore, processing component 701 may include one or more modules to facilitate interaction between processing component 701 and other components. For example, processing component 701 may include a multimedia module to facilitate interaction between multimedia components and processing component 701.

[0140] Memory 702 is configured to store various types of data to support the operation of device 70. Examples of such data include instructions for any application or method operating on device 70, contact data, phonebook data, messages, pictures, videos, etc. Memory 702 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.

[0141] Power supply assembly 703 provides power to the various components of device 70. Power supply assembly 703 may include a power management system, one or more power sources, and other components associated with generating, managing, and distributing power to device 70.

[0142] I / O interface 706 provides an interface between processing component 701 and peripheral interface modules, such as keyboards, click wheels, buttons, etc. These buttons may include, but are not limited to, home buttons, volume buttons, power buttons, and lock buttons.

[0143] Sensor assembly 707 includes one or more sensors for providing state assessments of various aspects of device 70. For example, sensor assembly 707 can detect the on / off state of device 70, the relative positioning of components such as the display and keypad of device 70, changes in the position of device 70 or a component of device 70, the presence or absence of user contact with device 70, the orientation or acceleration / deceleration of device 70, and temperature changes of device 70. Sensor assembly 707 may include a proximity sensor configured to detect the presence of nearby objects without any physical contact. Sensor assembly 707 may also include an optical sensor, such as a CMOS or CCD image sensor, for use in imaging applications. In some embodiments, sensor assembly 707 may also include an accelerometer, gyroscope, magnetometer, pressure sensor, or temperature sensor.

[0144] Communication component 705 is configured to facilitate wired or wireless communication between device 70 and other devices. Device 70 can access wireless networks based on communication standards, such as WiFi, 2G, or 3G, or combinations thereof. In one exemplary embodiment, communication component 705 receives broadcast signals or broadcast-related information from an external broadcast management system via a broadcast channel. In one exemplary embodiment, communication component 705 also includes a near-field communication (NFC) module to facilitate short-range communication. For example, the NFC module may be implemented based on radio frequency identification (RFID) technology, Infrared Data Association (IrDA) technology, ultra-wideband (UWB) technology, Bluetooth (BT) technology, and other technologies.

[0145] In an exemplary embodiment, the apparatus 70 may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the methods described above.

[0146] In an exemplary embodiment, a non-transitory computer-readable storage medium including instructions is also provided, such as a memory 702 including instructions, which can be executed by a processor 704 of the device 70 to perform the above-described method. For example, the non-transitory computer-readable storage medium may be a ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0147] The aforementioned computer-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.

[0148] 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.

[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] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the integer ambiguity fixing method executed by the above-mentioned integer ambiguity fixing device.

[0151] This application also provides a positioning service system, including multiple base stations, a data processing center, and terminal devices;

[0152] The reference station is used to acquire observation data from multiple satellites and send the observation data to the data processing center.

[0153] The data processing center is used to perform baseline calculations between reference stations based on observation data, and to perform overall modeling and calculation based on the baseline calculation results to obtain an error model. Based on the error model, a virtual reference station is established for the terminal equipment.

[0154] When the data processing center performs baseline calculations between reference stations based on the observation data, it is specifically used to implement the integer ambiguity fixing method described in the above embodiments.

[0155] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for fixing integer ambiguity, characterized in that, include: Based on the observation data at the current moment, determine the first single-difference wide-lane floating-point ambiguity of the target satellite at the current moment; The single-difference trend term error corresponding to the previous time point is obtained; the difference between the previous time point and the current time point is related to the orbital repetition period of the target satellite; the single-difference trend term error is a multipath error, and is determined based on the second single-difference wide-lane floating-point ambiguity of the target satellite at the previous time point and the corresponding receiver endcode phase deviation; the second single-difference wide-lane floating-point ambiguity is determined based on the observation data at the previous time point; The first single-difference wide-lane floating-point ambiguity is corrected based on the single-difference trend term error corresponding to the first single-difference wide-lane floating-point ambiguity to obtain the corrected first single-difference wide-lane floating-point ambiguity. The difference between the corrected first single-difference wide-lane floating-point ambiguity and the third single-difference wide-lane floating-point ambiguity of the reference satellite corresponding to the target satellite is determined as the double-difference wide-lane floating-point ambiguity of the target satellite; the double-difference wide-lane floating-point ambiguity is smoothed and rounded in real time to obtain the double-difference wide-lane integer ambiguity.

2. The method according to claim 1, characterized in that, The step of obtaining the error of the single difference trend term corresponding to the previous time step includes: Based on the current time, the orbital repetition period of the target satellite, and the corresponding lead time, determine the previous time corresponding to the current time; Based on the previous time and the first correspondence, the single difference trend term error corresponding to the previous time is determined from a plurality of pre-stored single difference trend term errors; the first correspondence includes a plurality of single difference trend term errors and a correspondence between a plurality of time.

3. The method according to claim 1 or 2, characterized in that, Before obtaining the error of the single difference trend term corresponding to the previous time step, the method further includes: Acquire observation data from multiple satellites within the reference time period of the previous time; the multiple satellites include a target satellite, which belongs to a target navigation system; Calculate the receiver endcode phase deviation at the previous time point based on observation data from multiple satellites; Based on the receiver endcode phase deviation, determine the single-difference wide-lane integer ambiguity of the target satellite at the previous time. Based on the single-difference wide-lane integer ambiguity, the error of the single-difference trend term corresponding to the previous time step is determined.

4. The method according to claim 3, characterized in that, The step of calculating the receiver endcode phase deviation at the previous time point based on observation data from multiple satellites includes: Based on a preset duration, the reference time period is divided into multiple time intervals; the preset duration is related to the stability period of the code phase deviation. For each continuous arc segment that meets the preset conditions in each time interval, based on the observation data of multiple non-GEO satellites in the target navigation system corresponding to the continuous arc segment, multiple second single-difference wide-lane floating-point ambiguities corresponding to the continuous arc segment are calculated, and the first mean value of the multiple second single-difference wide-lane floating-point ambiguities corresponding to the continuous arc segment is determined. For each time interval, the fractional part corresponding to the multiple first averages is extracted, and the receiver endcode phase deviation of the time interval is determined based on the multiple fractional parts.

5. The method according to claim 3, characterized in that, The step of determining the single-difference wide-lane integer ambiguity of the target satellite at the previous time based on the receiver endcode phase deviation includes: Based on the observation data of the target satellite corresponding to the continuous time period of the target, calculate multiple second single-difference wide-lane floating-point ambiguities corresponding to the continuous time period of the target; For each of the multiple second single-difference wide-lane floating-point ambiguities corresponding to the target continuous time period, a second difference is calculated between the second single-difference wide-lane floating-point ambiguity and the corresponding receiver endcode phase deviation; the target continuous arc segment includes the previous time period; Calculate the second mean of multiple second differences, and round the second difference to the nearest integer to obtain the single-difference wide-lane integer ambiguity corresponding to the continuous arc segment of the target. Then, determine the single-difference wide-lane integer ambiguity corresponding to the continuous arc segment of the target as the single-difference wide-lane integer ambiguity of the target satellite at the previous time.

6. The method according to claim 3, characterized in that, The step of determining the single-difference trend term error corresponding to the previous time step based on the single-difference wide-lane integer ambiguity includes: Calculate the first difference between the second single-difference wide-lane floating-point ambiguity and the single-difference wide-lane integer ambiguity of the target satellite at the previous time. The first difference is denoised to obtain the single difference trend term error corresponding to the previous time point.

7. A device for fixing integer ambiguity, characterized in that, include: The determination module is used to determine the first single-difference wide-lane floating-point ambiguity of the target satellite at the current moment based on the observation data at the current moment; The acquisition module acquires the single-difference trend term error corresponding to the previous time; the difference between the previous time and the current time is related to the orbital repetition period of the target satellite; The single-difference trend term error is a multipath error, and it is determined based on the second single-difference wide-lane floating-point ambiguity of the target satellite at the previous time and the corresponding receiver endcode phase deviation; the second single-difference wide-lane floating-point ambiguity is determined based on the observation data at the previous time. The correction module is used to correct the first single-difference wide-lane floating-point ambiguity based on the single-difference trend term error corresponding to the first single-difference wide-lane floating-point ambiguity, so as to obtain the corrected first single-difference wide-lane floating-point ambiguity. The processing module is used to determine the difference between the corrected first single-difference wide-lane floating-point ambiguity and the third single-difference wide-lane floating-point ambiguity of the reference satellite corresponding to the target satellite as the double-difference wide-lane floating-point ambiguity of the target satellite; and to perform real-time smoothing and rounding on the double-difference wide-lane floating-point ambiguity to obtain the double-difference wide-lane integer ambiguity.

8. A device for fixing integer ambiguity, characterized in that, include: At least one processor and memory; The memory stores computer-executed instructions; The at least one processor executes computer execution instructions stored in the memory, causing the at least one processor to perform the integer 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, implement the integer ambiguity fixing method as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the method for fixing integer ambiguity as described in any one of claims 1 to 6.

11. A positioning service system, comprising multiple base stations, a data processing center, and terminal equipment; The reference station is used to acquire observation data from multiple satellites and send the observation data to the data processing center. The data processing center is used to perform baseline calculations between reference stations based on observation data, and to perform overall modeling and calculation based on the baseline calculation results to obtain an error model. Based on the error model, a virtual reference station is established for the terminal equipment. When the data processing center performs baseline calculations between reference stations based on the observation data, it is specifically used to implement the method for fixing integer ambiguity as described in any one of claims 1 to 6.

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