Beidou / GNSS satellite time and space matching method and system based on angular distance

Abstract

The invention discloses a Beidou / GNSS satellite time and space matching method and system based on angular distance, and the method comprises the steps: building a satellite angular distance calculation model based on an elevating angle and an azimuth angle, and carrying out the calculation to form an angular distance numerical sequence; based on the constructed angular distance numerical sequence, screening satellite pairs corresponding to the minimum angular distance one by one, and sequentially performing satellite space matching; calculating an average angular distance of all satellites in a selected time period based on the constructed angular distance numerical sequence; and performing satellite time matching by taking the calculated average angular distance as a matching index of all satellites in a selected time period. The method is suitable for a Beidou / GNSS satellite signal grafting scene, is not influenced by poor accuracy of single elevation angle or azimuth angle matching, gives consideration to satellite time and space matching, can provide rich sample data for satellite precision positioning and integrated navigation integrity monitoring, and solves the problem of high cost of actual measurement data acquisition.

Description

Technical Field

[0001] The present invention relates to a Beidou / GNSS satellite time and space matching method and system based on angular distance. Background Art

[0002] Signal grafting is a typical semi-physical simulation test method, which is a compromise between field testing and laboratory testing. Its idea is to graft the error signal onto a "clean" signal so that the grafted signal can show the characteristics of the error signal. The data simulation method based on signal grafting has the advantages of low cost and high data utilization. Typical global navigation satellite system (GNSS) data simulation is achieved using Beidou / GNSS simulators and record and playback systems (RPS). Beidou / GNSS simulators perform theoretical simulations of various Beidou / GNSS information, while RPS records signals in real environments. Both can achieve research data acquisition in the laboratory. In addition, Beidou / GNSS data simulation can also draw on the idea of ​​signal grafting: obtain errors that have a greater impact on GNSS performance in complex urban environments, graft the errors onto Beidou / GNSS data collected in open environments or into satellite-to-ground distances calculated based on open environment coordinates, so as to achieve the purpose of simulating Beidou / GNSS data in complex urban environments.

[0003] The Beidou / GNSS positioning principle shows that the Beidou / GNSS positioning accuracy is not only related to the Beidou / GNSS observation accuracy, but also affected by the Beidou / GNSS satellite distribution. Beidou / GNSS receivers can observe multiple satellites at the same time, which results in multiple satellites being grafted in open environments and multiple errors being grafted in complex environments. In addition, it is impossible to guarantee that the grafted data is consistent with the grafted error length. Therefore, in Beidou / GNSS error grafting, it is necessary to consider the satellite matching between the grafted error and the grafted source to solve the problem of "many-to-many" satellites and inconsistent data length in Beidou / GNSS error grafting. Summary of the invention

[0004] In order to reduce the impact of satellite spatial distribution and time inconsistency on the correctness of Beidou / GNSS satellite signal grafting, the present invention considers the impact of satellite distribution on GNSS positioning, and proposes a satellite spatial matching method based on angular distance and a satellite time matching method based on average angular distance, so as to select the satellite and time period closest to the complex environment satellite distribution in an open environment, so as to ensure the accuracy of satellite matching.

[0005] According to one aspect of the present invention, a Beidou / GNSS satellite time and space matching method based on angular distance is provided, which is applicable to Beidou / GNSS satellite signal grafting scenarios, including: A satellite angular distance calculation model is established based on the altitude angle and azimuth angle to calculate and form an angular distance numerical sequence; Based on the constructed angular distance numerical sequence, the satellite pairs corresponding to the minimum angular distance are selected one by one, and satellite spatial matching is performed in sequence; Based on the constructed angular distance value sequence, the average angular distance of all satellites in the selected period is calculated; The calculated average angular distance is used as the matching index of all satellites in the selected time period to perform satellite time matching.

[0006] The above technical solution establishes angular distance information based on a combination of altitude angle and azimuth angle as a satellite matching indicator. At the same time, spatial consistency and temporal consistency are taken into account during the satellite matching process to ensure the continuity and correctness of the satellite motion trajectory within the time period after matching.

[0007] As a further technical solution, a satellite angular distance calculation model is established based on the altitude angle and the azimuth angle to calculate and form an angular distance numerical sequence, including: The satellite angular distance is calculated using the altitude and azimuth angles of the two satellites to obtain the angular distance value of the two satellites at that moment, and all satellite numbers are traversed one by one to form a sequence of angular distance values ​​between different satellites.

[0008] As a further technical solution, the satellite pairs corresponding to the minimum angular distance are selected one by one, and satellite spatial matching is performed in sequence, including: Determine the satellite pair corresponding to the minimum angular distance from the constructed sequence of angular distance values ​​between different satellites as the optimal matching result of the two satellites, and delete all angular distance values ​​corresponding to the two satellites in the sequence of angular distance values; The minimum angular distance is selected from the sequence of new angular distance values ​​in turn, and the satellite pair corresponding to the minimum angular distance at this time is determined until all satellite pairs are selected and the satellite spatial matching is completed.

[0009] As a further technical solution, the average angular distance of all satellites in the target period is calculated, including: Calculate the angular distance value of the satellite pair to be matched at each moment, take the average of the angular distance values ​​of the satellite pair to be matched in the selected time period, and obtain the average angular distance value of the satellite pair to be matched in the selected time period; The average angular distance of all satellites in the selected period is calculated using the obtained satellite pairings and the average angular distance of each satellite pair.

[0010] As a further technical solution, satellite time matching is performed, including: The average angular distance is used as the matching index of all satellite pairs in the selected period, and the average angular distance of satellites in multiple time periods is calculated by translation to obtain the average angular distance value sequence in multiple time periods; The average angular distance value of the satellite pairs in all time periods is judged, and the time period with the smallest average angular distance value is taken as the final result of satellite time matching to complete satellite time matching.

[0011] According to one aspect of the present invention, a Beidou / GNSS satellite time and space matching system based on angular distance is provided, which is applicable to Beidou / GNSS satellite signal grafting scenarios, including: A satellite angular distance calculation module is used to establish a satellite angular distance calculation model based on the altitude angle and the azimuth angle, and calculate and form an angular distance numerical sequence; The satellite space matching module is used to select the satellite pairs corresponding to the minimum angular distance one by one based on the constructed angular distance value sequence, and perform satellite space matching in sequence; The satellite average angular distance calculation module is used to calculate the average angular distance of all satellites in a selected period based on the constructed angular distance value sequence; The satellite time matching module is used to perform satellite time matching by using the calculated average angular distance as the matching index of all satellites in the selected time period.

[0012] According to one aspect of the present invention specification, there is provided a BeiDou / GNSS satellite time and space matching device based on angular distance, comprising a memory and a processor, wherein the memory stores program instructions executed by the processor, and the processor calls the program instructions to execute the steps of the BeiDou / GNSS satellite time and space matching method based on angular distance.

[0013] According to one aspect of the present specification, a non-transitory computer-readable storage medium is provided, wherein the non-transitory computer-readable storage medium stores computer instructions, wherein the computer instructions enable the computer to execute the steps of the Beidou / GNSS satellite time and space matching method based on angular distance.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention aims at Beidou / GNSS satellite signal grafting, constructs the angular distance information between satellites based on the altitude angle and azimuth angle, establishes the angular distance value as the satellite matching evaluation index, solves the limitation of inconsistent satellite sky distribution caused by relying only on the altitude angle or azimuth angle, and can effectively ensure the accuracy of satellite matching.

[0015] 2. The present invention takes into account both space matching and time matching when matching satellites. It not only requires good consistency in the satellite position at a fixed time, but also requires good consistency in the satellite motion trajectory within a certain period of time. It solves the problem of matching satellite jumps only through space matching and ensures the continuity of satellite matching results within a certain period of time.

[0016] 3. The present invention uses the open environment and complex environment actually collected to verify the satellite matching performance: satellite matching can achieve matching results with good consistency in satellite sky distribution in both data collected simultaneously in the same area and dynamic vehicle-mounted data. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief introduction is given below to the drawings used in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 A schematic flow chart of a BeiDou / GNSS satellite time and space matching method based on angular distance provided in an embodiment of the present invention; Figure 2 A schematic diagram of the principle of Beidou / GNSS satellite time and space matching based on angular distance provided in an embodiment of the present invention; Figure 3 A schematic diagram of the angular distance of a satellite at a fixed time provided by an embodiment of the present invention; Figure 4 A schematic diagram of the angular distances of satellites at different times provided by an embodiment of the present invention; Figure 5 A flow chart of satellite space matching based on angular distance provided by an embodiment of the present invention; Figure 6 A flow chart of satellite time matching based on average angular distance provided by an embodiment of the present invention; Figure 7 (a)-(b) are schematic diagrams of satellite space matching results of the same group of data simulation provided by an embodiment of the present invention, (a) open environment sky map, (b) complex environment sky map; Figure 8 (a)-(b) are schematic diagrams showing the effect of the average angular distance restriction provided in an embodiment of the present invention on satellite time and space matching, (a) without the average angular distance restriction, (b) with the average angular distance restriction (threshold 30°); Fig. 9 A structural block diagram of a BeiDou / GNSS satellite time and space matching system based on angular distance provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0019] It should be noted that: The azimuth and altitude of satellites are often used to describe the position of satellites in the sky, so it is reasonable to use azimuth and altitude to construct an indicator to measure the proximity of satellites. In astronomy, angular distance is used to describe the distance relationship between stars observed from the earth. Angular distance is defined as the angle between the straight lines pointed by the observer to the two objects when the two objects are observed from a different position (i.e., a third point). Angular distance is used as an indicator to measure the proximity of satellites in Beidou / GNSS satellite matching. In Beidou / GNSS satellite spatial matching, the smaller the angular distance, the closer the distribution of satellites in the sky. The distribution of Beidou / GNSS satellites is strictly bound to time, and time matching is essentially still based on the spatial distribution of satellites. Spatial matching is selected based on a certain moment, while time matching processes time period data, and it is necessary to calculate the angular distance at each moment in the time period to measure the proximity of satellites in the time period.

[0020] The terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions, for example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to the steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0021] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. In addition, the technical features in the various embodiments or single embodiments provided by the present invention are arbitrarily combined with each other to form a new technical solution. This combination is not restricted by the sequence of steps and / or the structural composition mode, but must be based on the ability of ordinary technicians in this field to achieve. When the combination of technical solutions is contradictory or cannot be achieved, it should be considered that this combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] See also Figure 1 The embodiment of the present invention provides a Beidou / GNSS satellite time matching and space matching method based on angular distance, which is suitable for Beidou / GNSS satellite signal grafting scenarios, and includes a satellite angular distance calculation sub-process, a satellite space matching sub-process, a satellite average angular distance calculation sub-process and a satellite time matching sub-process.

[0023] Among them, the satellite angular distance calculation subprocess mainly uses the altitude angle and azimuth angle of two satellites to calculate the satellite angular distance, obtains the angular distance value of the two satellites at that moment, and traverses all satellites one by one to form a sequence of angular distance values ​​between different satellites.

[0024] The satellite space matching subprocess mainly determines the satellite pair corresponding to the minimum angular distance from the angular distance value sequence as the optimal matching result of the two satellites, and deletes all angular distance values ​​corresponding to the two satellites in the angular distance value sequence. The angular distance values ​​corresponding to the two satellites will no longer participate in the subsequent minimum angular distance screening process. The minimum angular distance is selected from the new angular distance value sequence in turn, and the satellite pair corresponding to the minimum angular distance at this time is determined until all satellite pairs are selected and the satellite space matching is completed.

[0025] The satellite average angular distance calculation subprocess first calculates the angular distance value of the satellite pair to be matched at each moment, and then takes the average of the angular distance values ​​of the satellite pair in the selected time period to obtain the average angular distance of the satellite pair in the time period. Then, the obtained satellite pairing and the average angular distance of each satellite pair are used to calculate the average angular distance of all satellites in the time period.

[0026] The satellite time matching calculation subprocess is performed after the angular distance calculation, spatial matching and average angular distance calculation. The average angular distance is used as the matching index for all satellite pairs in the period. The satellite average angular distance calculation in multiple time periods is realized through translation, and the average angular distance value sequence in multiple time periods is obtained. The average angular distance values ​​of satellite pairs in all time periods are judged, and the period with the smallest average angular distance value is taken as the final result of satellite time matching to complete satellite time matching.

[0027] The embodiment of the present invention constructs angular distance information between satellites based on altitude angle and azimuth angle, and establishes an angular distance value as a satellite matching evaluation index; taking into account satellite space matching and time matching, the angular distance evaluation is used to ensure that the satellite position has good consistency at a fixed time, and the average angular distance evaluation is used to ensure that the satellite motion trajectory has good consistency within a certain period of time.

[0028] See also Figure 2 The figure shows the technical principle framework of Beidou / GNSS satellite time and space matching based on angular distance provided by an embodiment of the present invention, including the processes of inputting satellite data to be matched, calculating satellite angular distance, satellite space matching and its judgment, calculating satellite average angular distance, satellite time matching and its judgment, etc.

[0029] (1) Satellite space matching implementation method The schematic diagram of the angular distance between two satellites when the satellites are spatially matched is shown in Figure 3, two satellites can construct two vectors with the ground observation point respectively, and the satellite angular distance is the angle between the two satellite vectors. The azimuth and altitude angles of the satellite are used to represent the unit vector of the line of sight of satellite A. , satellite B line of sight direction unit vector , as follows: (1) In the formula, and Satellite A is The azimuth and altitude at the time, and Satellite B is The azimuth and altitude at the moment. According to the relationship between the vector inner product and the angle, we can get: (2) The satellite angular distance can be calculated by vector inner product and inverse trigonometric function operations. .

[0030] (3) According to the satellite angular distance calculation formula (3), the angular distance between any two satellites can be given, and the angular distance value is used to judge the object of spatial matching. The implementation process of satellite spatial matching is given below.

[0031] During satellite space matching, the open environment The number of satellites observed at any time is m, and the complex environment There are n satellites observed at any time. Theoretically, there are open environment satellites and complex environment satellites. There are several matching situations, each of which needs to be calculated based on the matching relationship of the satellites. The angular distance of each pair of satellites is averaged to measure the proximity of the satellites under the current matching conditions, and the case with the smallest average angular distance is selected as the matching relationship between the open environment satellite and the complex environment satellite. However, the above-mentioned method of traversing multiple satellites for matching has problems such as excessive calculation and long time consumption in actual use, and cannot meet the matching calculation efficiency requirements. Therefore, in order to improve the matching efficiency and matching reliability, the present invention simplifies the satellite space matching, and changes the overall matching of all observed satellites into satellite-by-satellite matching.

[0032] According to the angular distance calculation formula (1), the angular distance between the open environment satellite and the complex environment satellite can be calculated as follows: The angular distance of each satellite pair is used to determine the spatial matching of the satellite matching relationship. The spatial matching of the satellite matching relationship satisfies two principles. Principle 1: The successfully matched satellites cannot be reused, and the satellites that have completed the matching do not participate in the subsequent matching of other satellites. Principle 2: Prioritize satellite pairs with small angular distances, and select the satellite pairs with the smallest current angular distance in turn until there are no satellites to choose from, and complete the matching of all satellites. The detailed implementation process of satellite spatial matching is as follows: Figure 5 This document is not limited to open environment Three satellites A, B, and C at time, complex environment The two satellites at time D and E are used as examples of the present invention to illustrate the satellite space matching process and the above algorithm flow: First, the angular distance between each open environment satellite and each complex environment satellite is calculated according to the angular distance calculation formula (1), the angular distance value between each open environment satellite and each complex environment satellite is obtained, and an angular distance value sequence is formed.

[0033] Secondly, the minimum angular distance is selected from the above angular distance numerical sequence, and the satellite pair corresponding to the minimum angular distance is determined. Here, satellite C and satellite D are taken as an example as the satellite pair at this moment.

[0034] Furthermore, the satellite pair corresponding to the minimum angular distance is used to determine the successfully matched satellite at this time. Here, satellite C and satellite D are taken as an example as the successfully matched satellite pair. The successfully matched satellite no longer participates in the subsequent satellite matching, that is, the minimum angular distance of the completed satellite matching is deleted from the angular distance value sequence. Then, the open environment satellites are A and B, and the complex environment satellite is E.

[0035] Then, the minimum angular distance is selected from the new angular distance value sequence, and the satellite pair corresponding to the minimum angular distance is determined. The successfully matched satellite at this time is determined through the satellite pair corresponding to the minimum angular distance as the successfully matched satellite pair.

[0036] Finally, the above process is repeated until all available satellites are matched, ending the satellite space matching process and establishing a successfully matched satellite pair.

[0037] The above process can complete the spatial matching of open environment satellites and complex environment satellites, and obtain satellite pairs that can be spatially matched, providing a basic guarantee for the correctness of subsequent satellite signal grafting work.

[0038] (2) Satellite time matching implementation method Satellite space matching is to calculate and analyze the satellite pair at a certain moment, while satellite time matching needs to consider all the data in the time period, that is, to calculate the angular distance at each moment in the time period to measure the matching degree of the satellites in the time period. Figure 4 , the observable periods of satellite A and satellite B are and , and the time lengths of the two are consistent. Time Satellite A and The angular distance of satellite B at time . Using the average angular distance Indicates time period Satellite A and time period The closeness of the distribution of satellite B in the sky, the average angular distance between satellite A and satellite B in a certain period of time is calculated as follows: (4) In the process of satellite time matching of the angular distance between any two satellites, the angular distance between satellite A and satellite B at a certain moment can be obtained according to the satellite angular distance calculation formula (3), and then the average angular distance formula (4) is used to calculate the average angular distance between satellite A and satellite B in a certain period of time.

[0039] During the satellite time matching process, the open environment data is During the period Satellite data, the satellite signal to be grafted is During the period There are observation errors for satellites. In order to make full use of satellite observation data, the length of satellite time matching is retained. Satellite data of length , matching in complex environment data The satellite time matching process is as follows: Figure 6 As shown, the present invention is The implementation process is described as an example, but the present invention is not limited to being applicable to The specific process of satellite time matching is as follows: Step 1: When When the satellite error data to be grafted is retained, the entire segment starts from the open environment data. The interception time length is Satellite data, open environment The number of satellite observations during the period is particles, complex environment The number of satellite observations during the period is Particles.

[0040] Step 2: Calculate the satellite matching between the satellite data in the open environment interception period and the satellite error data to be grafted. It should be noted that the present invention uses the mean angular distance to describe the degree of proximity of the sky distribution of two satellites in a certain period of time. Therefore, firstly calculate the angular distance value of the satellite pair composed of the satellite data in the open environment interception period and the satellite error data to be grafted at each moment according to formula (3): , then take the average of the angular distance values ​​of the satellite pair in the selected period to obtain the average angular distance of the satellite pair in the period , and the mean angular distance is used as the matching index of this satellite pair during this period.

[0041] Step 3: Calculate the mean angular distance of all satellite pairs in the same period as above , and complete the satellite-space pairing according to the satellite-space matching process.

[0042] Step 4: Using the satellite pairings and the mean angular distances of each satellite pair calculated in step 3, calculate the average angular distance according to formula (4): , the present invention uses the average angular distance as the matching index of all satellite pairs in this period.

[0043] Step 5: The data capture window is shifted by one epoch in the open environment satellite data (i.e., the shift is expressed as ), as the next interception period, repeat steps 2-4 until , indicating that the entire section of open environment satellite data has been traversed.

[0044] Step 6: Take the period with the smallest average angular distance between the satellite pairs in all periods of the above translation process as the final result of satellite time matching.

[0045] Since it is necessary to traverse the entire satellite data of the open environment, if the satellite space matching process is used to traverse all situations, the amount of satellite matching calculation will be very large. Even if the simplified satellite space matching method is used to only calculate the angular distance of the satellite at each corresponding time, the amount of calculation in this case is also very large. Therefore, considering the directional characteristics of the satellite movement, the present invention can be simplified in the specific implementation process to only select a few typical moments for average angular distance calculation, such as only calculating the average angular distance at the start time, middle time and end time of the time period, and taking the time period with the smallest average angular distance value of the three moments as the satellite time matching result.

[0046] The embodiment of the present invention implements and verifies the method of the present invention based on the PC side, see Figure 7 (a)-(b) and Figure 8 (a)-(b).

[0047] The most intuitive way to verify the correctness of the satellite time-space matching method is to directly check the satellite matching in the same area and the same period, that is, the open environment data and the complex environment data are collected in the same area at the same time. In this case, the open environment satellite can perfectly match the complex environment satellite. According to the above implementation process, the present invention prepares 3 hours of satellite data to verify the satellite time-space matching method. During the verification process, a scenario is set to simulate that the length of the complex environment data is greater than the length of the open environment data, and the middle 1 hour of data is intercepted as the open environment data, and the complete 3 hours of data is used as the complex environment data. The purpose of this verification design is to verify both the satellite space matching capability and the satellite time matching capability. Figure 7 (a) and (b) are the satellite sky images of open environment and complex environment respectively under the experimental verification. The same color tracks in (a) and (b) represent the satellites that have been successfully matched, while the gray tracks represent the satellites that have not been successfully matched. The "r" after the satellite number indicates an open environment satellite, and the red indicates that the satellite has been successfully matched; the "mp" after the satellite number indicates a complex environment satellite. Figure 7 As can be seen from (a) and (b), the satellites in the open environment and the satellites in the complex environment have achieved correct matching in both space and time. In addition, to further verify the correctness of the satellite spatiotemporal matching, the present invention also sets a scenario where the length of the urban complex environment data is shorter than the length of the open environment data, intercepts the middle 1 hour of data as the complex environment data, and the complete 3 hours of data as the open environment data. The satellite matching results obtained by the test are consistent with Figure 7 They are basically the same and can also achieve correct satellite time and space matching, so the specific satellite sky distribution map will not be repeated.

[0048] A special note: the reason why there is no interruption in the satellite trajectory in the sky map is that the present invention also regards the interruption of satellite signals as a special extreme (environmental) error, so the satellite error sequence is continuous (i.e., satellite observation is continuous), so the satellite trajectory is also continuous. At this time, when calculating the azimuth and altitude of the satellite, first determine the start and end time of the satellite with real observation values, and then calculate the azimuth and altitude within this period. The azimuth and altitude calculation is not performed during the satellite interruption period.

[0049] In addition, in order to further verify the satellite matching situation at different time periods of a day, the present invention also uses dynamic measured data in open environments and complex environments to investigate the dynamic satellite matching effect and the average angular distance constraint. Figure 8 The satellite matching results in open environment and complex environment under dynamic conditions considering the average angular distance constraint are given. Overall, after adding the average angular distance constraint, the satellite matching pairs with large trajectories can be eliminated, and the retained trajectories are relatively close. Specifically, Figure 8In (a), the average angular distance between G32_r and G31_mp (yellow) is 38.22°, the average angular distance between G16_r and G04_mp (orange) is 31.17°, and the average angular distance between G27_r and G28_mp (light purple) is 64.91°. The sky distribution of these three groups of open environment satellites and complex environment satellites is obviously different, and their average angular distance values ​​are also large. If the average angular distance value is not constrained, the sky distribution characteristics after satellite spatiotemporal matching will be greatly different. Therefore, the constraint condition that the average angular distance is less than or equal to 30° is adopted, and the satellite matching results whose average angular distance meets this constraint condition are selected (see Figure 8 (b)) can effectively eliminate unreasonable satellite matching pairs and ensure that the sky distribution characteristics after satellite matching remain basically consistent.

[0050] The present invention establishes angular distance information based on a combination of altitude angle and azimuth angle as a satellite matching index, while taking into account both spatial consistency and temporal consistency during the satellite matching process, thereby ensuring the continuity and correctness of the satellite motion trajectory within the time period after matching.

[0051] The implementation basis of each embodiment of the present invention is to implement programmed processing through a device with a processor function. Therefore, in engineering practice, the technical solutions and functions of each embodiment of the present invention are encapsulated into various modules. Based on this reality, on the basis of the above embodiments, an embodiment of the present invention provides a Beidou / GNSS satellite time and space matching system based on angular distance, which is used to execute a Beidou / GNSS satellite time and space matching method based on angular distance in the above method embodiment.

[0052] See also Fig. 9 The system includes: a satellite angular distance calculation module, which is used to establish a satellite angular distance calculation model based on the altitude angle and the azimuth angle, and calculate to form an angular distance value sequence; a satellite space matching module, which is used to screen satellite pairs corresponding to the minimum angular distance one by one based on the constructed angular distance value sequence, and perform satellite space matching in sequence; a satellite average angular distance calculation module, which is used to calculate the average angular distance of all satellites in a selected time period based on the constructed angular distance value sequence; and a satellite time matching module, which is used to perform satellite time matching by using the calculated average angular distance as a matching index for all satellites in a selected time period.

[0053] The embodiment of the present invention provides a BeiDou / GNSS satellite time and space matching system based on angular distance, which is aimed at the problem of "many-to-many" satellites and inconsistent data length in GNSS / BeiDou error grafting. Fig. 9Several modules in it build the angular distance information between satellites based on altitude angle and azimuth angle, and establish the angular distance value as the satellite matching evaluation index; taking into account the satellite space matching and time matching, the angular distance is used to evaluate the good consistency of the satellite position at a fixed time, and the average angular distance is used to evaluate the good consistency of the satellite motion trajectory within a certain period of time.

[0054] It should be noted that the system embodiment provided by the present invention is used to implement the methods in the above method embodiment as well as the methods in other method embodiments provided by the present invention. The only difference is that the corresponding functional modules are set. The principle is basically the same as the principle of the above system embodiment provided by the present invention. As long as the technical personnel in this field refer to the specific technical solutions in other method embodiments on the basis of the above system embodiment, obtain the corresponding technical means and the technical solutions composed of these technical means by combining the technical features, and on the premise of ensuring the practicality of the technical solutions, improve the modules in the above system embodiment to obtain the corresponding system class embodiments, which are used to implement the methods in other method class embodiments. For example: Based on the content of the above system embodiment, as a preferred embodiment, a Beidou / GNSS satellite time and space matching system based on angular distance is provided in the embodiment of the present invention, and the satellite angular distance calculation module is also used to execute the following instructions: The satellite angular distance is calculated using the altitude and azimuth angles of the two satellites to obtain the angular distance value of the two satellites at that moment, and all satellite numbers are traversed one by one to form a sequence of angular distance values ​​between different satellites.

[0055] Based on the content of the above system embodiment, as a preferred embodiment, a Beidou / GNSS satellite time and space matching system based on angular distance is provided in the embodiment of the present invention, and the satellite space matching module is also used to execute the following instructions: Determine the satellite pair corresponding to the minimum angular distance from the constructed sequence of angular distance values ​​between different satellites as the optimal matching result of the two satellites, and delete all angular distance values ​​corresponding to the two satellites in the sequence of angular distance values; The minimum angular distance is selected from the sequence of new angular distance values ​​in turn, and the satellite pair corresponding to the minimum angular distance at this time is determined until all satellite pairs are selected and the satellite spatial matching is completed.

[0056] Based on the content of the above system embodiment, as a preferred embodiment, a Beidou / GNSS satellite time and space matching system based on angular distance is provided in the embodiment of the present invention, and the satellite average angular distance calculation module is also used to execute the following instructions: Calculate the angular distance value of the satellite pair to be matched at each moment, take the average of the angular distance values ​​of the satellite pair to be matched in the selected time period, and obtain the average angular distance value of the satellite pair to be matched in the selected time period; The average angular distance of all satellites in the selected period is calculated using the obtained satellite pairings and the average angular distance of each satellite pair.

[0057] Based on the content of the above system embodiment, as a preferred embodiment, a Beidou / GNSS satellite time and space matching system based on angular distance is provided in the embodiment of the present invention, and the satellite time matching module is also used to execute the following instructions: The average angular distance is used as the matching index of all satellite pairs in the selected period, and the average angular distance of satellites in multiple time periods is calculated by translation to obtain the average angular distance value sequence in multiple time periods; The average angular distance value of the satellite pairs in all time periods is judged, and the time period with the smallest average angular distance value is taken as the final result of satellite time matching to complete satellite time matching.

[0058] Based on the same inventive concept as the above-mentioned embodiment, an embodiment of the present invention also provides a Beidou / GNSS satellite time and space matching device based on angular distance, including a memory and a processor, wherein the memory stores program instructions executed by the processor, and the processor calls the program instructions to execute the steps of the Beidou / GNSS satellite time and space matching method based on angular distance.

[0059] In an embodiment of the present invention, the memory may be a non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), etc., or a volatile memory (volatile memory), such as a random-access memory (RAM). The memory is any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory in an embodiment of the present invention may also be a circuit or any other device that can implement a storage function, for storing program instructions and / or data.

[0060] In the embodiments of the present invention, the processor may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and may implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. A general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the method disclosed in the embodiments of the present invention may be directly embodied as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor.

[0061] Based on the same inventive concept as the above-mentioned embodiment, an embodiment of the present invention also provides a non-transitory computer-readable storage medium, which stores computer instructions, and the computer instructions enable the computer to execute the steps of the Beidou / GNSS satellite time and space matching method based on angular distance.

[0062] In summary, the present invention provides a Beidou / GNSS satellite time matching and space matching method based on angular distance, including (1) establishing a satellite angular distance calculation model based on satellite altitude angle and azimuth angle; (2) satellite space matching determines the satellite pair corresponding to the minimum angular distance from the angular distance value sequence as the optimal result of the space matching of the two satellites, and selects the minimum angular distance from the new angular distance value sequence in turn to complete the space matching of all satellites; (3) using the angular distance value of the satellite pair to be matched at each moment to calculate the angular distance average, and using the obtained satellite pairing and the angular distance average of each satellite pair to calculate the average angular distance of all satellites in the time period; (4) realizing the calculation of the satellite average angular distance in multiple time periods by translation, obtaining the average angular distance value sequence in multiple time periods, judging the average angular distance value of the satellite pairs in all time periods, and taking the time period with the smallest average angular distance value as the final result of satellite time matching to complete satellite time matching. The present invention is applicable to the scenario of Beidou / GNSS satellite signal grafting. It is not affected by the poor matching accuracy of a single altitude angle or azimuth angle, and takes into account satellite time and space matching. It can provide rich sample data for satellite precise positioning and integrated navigation integrity monitoring, and solve the high cost problem of measured data collection.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A BeiDou / GNSS satellite time and space matching method based on angular distance is applicable to BeiDou / GNSS satellite signal grafting scenarios, and is characterized by: include: A satellite angular distance calculation model is established based on the altitude angle and azimuth angle to calculate and form an angular distance numerical sequence; Based on the constructed angular distance numerical sequence, the satellite pairs corresponding to the minimum angular distance are selected one by one, and satellite spatial matching is performed in sequence; Based on the constructed angular distance value sequence, the average angular distance of all satellites in the selected period is calculated; The calculated average angular distance is used as the matching index of all satellites in the selected time period to perform satellite time matching.

2. The BeiDou / GNSS satellite time and space matching method based on angular distance according to claim 1, characterized in that: A satellite angular distance calculation model is established based on the altitude angle and azimuth angle to calculate the angular distance numerical sequence, including: The satellite angular distance is calculated using the altitude and azimuth angles of the two satellites to obtain the angular distance value of the two satellites at that moment, and all satellite numbers are traversed one by one to form a sequence of angular distance values ​​between different satellites.

3. The BeiDou / GNSS satellite time and space matching method based on angular distance according to claim 1, characterized in that: The satellite pairs corresponding to the minimum angular distance are selected one by one, and satellite spatial matching is performed in sequence, including: Determine the satellite pair corresponding to the minimum angular distance from the constructed sequence of angular distance values ​​between different satellites as the optimal matching result of the two satellites, and delete all angular distance values ​​corresponding to the two satellites in the sequence of angular distance values; The minimum angular distance is selected from the sequence of new angular distance values ​​in turn, and the satellite pair corresponding to the minimum angular distance at this time is determined until all satellite pairs are selected and the satellite spatial matching is completed.

4. The BeiDou / GNSS satellite time and space matching method based on angular distance according to claim 1, characterized in that: Calculate the average angular distance of all satellites during the target period, including: Calculate the angular distance value of the satellite pair to be matched at each moment, take the average of the angular distance values ​​of the satellite pair to be matched in the selected time period, and obtain the average angular distance value of the satellite pair to be matched in the selected time period; The average angular distance of all satellites in the selected period is calculated using the obtained satellite pairings and the average angular distance of each satellite pair.

5. The BeiDou / GNSS satellite time and space matching method based on angular distance according to claim 4, characterized in that: Perform satellite time matching, including: The average angular distance is used as the matching index of all satellite pairs in the selected period, and the average angular distance of satellites in multiple time periods is calculated by translation to obtain the average angular distance value sequence in multiple time periods; The average angular distance value of the satellite pairs in all time periods is judged, and the time period with the smallest average angular distance value is taken as the final result of satellite time matching to complete satellite time matching.

6. The BeiDou / GNSS satellite time and space matching system based on angular distance is suitable for BeiDou / GNSS satellite signal grafting scenarios, characterized by: include: A satellite angular distance calculation module is used to establish a satellite angular distance calculation model based on the altitude angle and the azimuth angle, and calculate and form an angular distance numerical sequence; The satellite space matching module is used to select the satellite pairs corresponding to the minimum angular distance one by one based on the constructed angular distance value sequence, and perform satellite space matching in sequence; The satellite average angular distance calculation module is used to calculate the average angular distance of all satellites in a selected period based on the constructed angular distance value sequence; The satellite time matching module is used to perform satellite time matching by using the calculated average angular distance as the matching index of all satellites in the selected time period.

7. A BeiDou / GNSS satellite time and space matching device based on angular distance, characterized in that: It comprises a memory and a processor, wherein the memory stores program instructions executed by the processor, and the processor calls the program instructions to execute the steps of the Beidou / GNSS satellite time and space matching method based on angular distance as described in any one of claims 1 to 5.

8. A non-transitory computer-readable storage medium, characterized in that: The non-transitory computer-readable storage medium stores computer instructions, which enable the computer to execute the steps of the Beidou / GNSS satellite time and space matching method based on angular distance as described in any one of claims 1 to 5.

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