Occultation reference star selection method, device, electronic device and storage medium

Abstract

The present invention provides a method, device, electronic device and storage medium for selecting an occultation reference star, including: obtaining a target time period corresponding to an occultation event; determining an alternative reference star according to whether there is an effective observation quantity of the reference star corresponding to the occultation event in the target time period; obtaining a target frequency corresponding to a target observation frequency point; obtaining multipath data corresponding to the alternative reference star in the target time period according to the target frequency; and determining the target reference star corresponding to the occultation event according to the multipath data. In an embodiment of the present invention, by selecting a target reference star in an occultation event, the candidate reference star is first determined by searching for a satellite continuously tracked during the occultation event from positioning satellites, and then the multipath estimation method is used to evaluate the multipath data of the satellites of these alternative reference stars during the entire occultation event, and then the target reference star is determined according to the multipath data. In this way, the reference star with the highest accuracy among all reference stars can be obtained, and the inversion error caused by excessive multipath error of the reference star can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of satellite navigation technology, and in particular to a method, device, electronic equipment and storage medium for selecting an occultation reference star. Background Art

[0002] With the development of global navigation satellite system (GNSS) navigation technology, a variety of remote sensing detection technologies based on GNSS technology have gradually developed, and global navigation satellite system (GNSS) radio occu ltation (RO) technology is one of them. GNSS-RO technology is based on GNSS occultation signals. Through inversion, it can obtain information such as atmospheric refractive index, temperature, humidity, pressure, and ionospheric electron density. Occultation detection has gradually become a hot topic of research due to its advantages of all-weather, high precision, and global coverage.

[0003] At present, occultation receivers generally use the occultation single difference method to eliminate the influence of clock errors by subtracting the corresponding reference star observations from the occultation observations. For an occultation event, there may be multiple available reference stars. Usually, the reference star with the highest elevation angle is used as the reference star corresponding to the occultation event. However, due to the complex installation conditions on the satellite, there are often multipath signals from the satellite surface or solar panels, which deteriorate the accuracy of the reference star and thus lead to poor occultation inversion accuracy. Summary of the invention

[0004] In view of this, the present invention aims to propose a method, device, electronic device and storage medium for selecting an occultation reference star, which solves the problem of the influence of multipath effect on the accuracy of the reference star.

[0005] According to a first aspect of the present invention, a method for selecting an occultation reference star is provided, the method comprising:

[0006] Obtain a target time period corresponding to the occultation event, wherein the target time period is the start time and end time corresponding to the occultation event;

[0007] Determining a candidate reference star according to a target time period corresponding to the occultation event;

[0008] Get the target frequency corresponding to the target observation frequency point;

[0009] Acquire multipath data corresponding to the candidate reference star in the target time period according to the target frequency;

[0010] A target reference star corresponding to the occultation event is determined according to the multipath data.

[0011] Optionally, determining a candidate reference star according to a target time period corresponding to the occultation event includes:

[0012] Determine whether there is valid observation quantity of the reference star in the target time period;

[0013] If so, the reference star is used as an alternative reference star.

[0014] Optionally, acquiring a target frequency corresponding to a target observation frequency point includes:

[0015] Receive the target observation frequency sent by the user;

[0016] A target frequency corresponding to the target observation frequency point is obtained according to the target observation frequency point.

[0017] Optionally, the candidate reference star has a single GNSS system dual-frequency observation, and acquiring the multipath data corresponding to the candidate reference star in the target time period according to the target frequency includes:

[0018] Determine the pseudorange observation amount of the candidate reference star at any time and the carrier phase observation amount according to the target frequency;

[0019] The multipath data corresponding to each candidate reference star in the target time period is obtained through dual-frequency data, pseudo-range observations, and carrier phase observations.

[0020] Optionally, the multipath data corresponding to the candidate reference star in the target time period is obtained by the following formula:

[0021]

[0022]

[0023] In the above formula, i represents the satellite number, k represents the observation frequency number, and f k represents the frequency of the observed frequency point, represents the pseudo-range observation of reference frequency point k of satellite number i at time t, represents the carrier phase observation of reference frequency point k of satellite number i at time t, and j is an arbitrary value of k.

[0024] Optionally, determining a target reference star corresponding to the occultation event according to the multipath data includes:

[0025] Performing mean processing on all multipath data corresponding to each candidate reference star in the target time period to obtain a multipath mean corresponding to each candidate reference star;

[0026] A target reference star corresponding to the occultation event is determined according to the multipath mean.

[0027] Optionally, determining a target reference star corresponding to the occultation event according to the multipath data includes:

[0028] Performing standard deviation processing on all multipath data corresponding to the candidate reference star in the target time period to obtain a multipath standard deviation corresponding to each candidate reference star;

[0029] A target reference star corresponding to the occultation event is determined according to the multipath standard deviation.

[0030] According to a second aspect of the present invention, there is provided a device for selecting an occultation reference star, the device comprising:

[0031] A first acquisition module is used to acquire a target time period corresponding to the occultation event, wherein the target time period is a start time and an end time corresponding to the occultation event;

[0032] A first determination module is used to determine a candidate reference star according to a target time period corresponding to the occultation event;

[0033] The second acquisition module is used to acquire the target frequency corresponding to the target observation frequency point;

[0034] A third acquisition module is used to acquire multipath data corresponding to the candidate reference star in the target time period according to the target frequency;

[0035] The second determination module is used to determine the target reference star corresponding to the occultation event according to the multipath data.

[0036] Optionally, the first determining module includes:

[0037] The first determination submodule is used to determine whether there is a valid observation quantity of the reference star in the target time period;

[0038] The second determining submodule is configured to, if yes, use the reference star as a candidate reference star.

[0039] Optionally, the second acquisition module includes:

[0040] The receiving submodule is used to receive the target observation frequency sent by the user;

[0041] The acquisition submodule is used to acquire the target frequency corresponding to the target observation frequency point according to the target observation frequency point.

[0042] Optionally, the third acquisition module includes:

[0043] A third determination submodule is used to determine the pseudorange observation amount of the candidate reference star at any time and the carrier phase observation amount according to the target frequency;

[0044] The multipath data acquisition submodule is used to acquire the multipath data corresponding to each candidate reference star in the target time period through dual-frequency data, pseudo-range observations, and carrier phase observations.

[0045] Optionally, the second determining module includes:

[0046] A multipath mean value acquisition module is used to perform mean processing on all multipath data corresponding to each candidate reference star in the target time period to obtain a multipath mean value corresponding to each candidate reference star;

[0047] The fourth determination submodule is used to determine the target reference star corresponding to the occultation event according to the multipath mean.

[0048] Optionally, the second determining module includes:

[0049] A multipath standard deviation acquisition module, used to perform standard deviation processing on all multipath data corresponding to the candidate reference star in the target time period to obtain a multipath standard deviation corresponding to each candidate reference star;

[0050] The fifth determination submodule is used to determine the target reference star corresponding to the occultation event according to the multipath standard deviation.

[0051] According to a third aspect of the present invention, there is provided an electronic device, comprising:

[0052] processor;

[0053] a memory for storing processor-executable instructions;

[0054] Wherein, the processor is configured to execute the instructions to implement the steps of the occultation reference star selection method as described in any one of the first aspects.

[0055] According to a fourth aspect of the present invention, there is provided a storage medium storing a computer program, wherein when the computer program is executed by a processor, the steps of the method for selecting a reference star for occultation are implemented as described in any one of the first aspect.

[0056] An embodiment of the present invention provides a method for selecting an occultation reference star, which obtains a target time period corresponding to an occultation event, wherein the target time period is the start time and the end time corresponding to the occultation event; determines an alternative reference star according to the target time period corresponding to the occultation event; obtains a target frequency corresponding to a target observation frequency point; obtains multipath data corresponding to the alternative reference star in the target time period according to the target frequency; and determines the target reference star corresponding to the occultation event according to the multipath data. In the embodiment of the present invention, by selecting a target reference star in an occultation event, firstly, a satellite continuously tracked during the occultation event is searched from positioning satellites to determine the alternative reference star, and then the multipath data of the satellites of these alternative reference stars during the entire occultation event are evaluated by a multipath estimation method, and then the target reference star is determined according to the multipath data. In this way, the reference star with the highest accuracy among all reference stars can be obtained, and the inversion error caused by the excessive multipath error of the reference star can be avoided. Moreover, when the target reference star is used to calculate the additional phase to invert the refractive index, the occultation inversion accuracy can be improved.

[0057] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0059] Figure 1 is a flowchart of the steps of a method for selecting an occultation reference star provided by an embodiment of the present invention;

[0060] Figure 2 is a flowchart of the steps of another method for selecting a reference star for occultation provided by an embodiment of the present invention;

[0061] Figure 3 is a flowchart of the steps of another method for selecting a reference star for occultation provided by an embodiment of the present invention;

[0062] Figure 4 is a flowchart of the steps of another method for selecting a reference star for occultation provided by an embodiment of the present invention;

[0063] Figure 5 is a device block diagram of a device for selecting an occultation reference star provided by an embodiment of the present invention;

[0064] Figure 6It is a schematic diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0065] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0066] The terms "first", "second", etc. in the specification and claims of the present invention are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0067] In conjunction with the accompanying drawings, a method, device, electronic device and storage medium for selecting an occultation reference star provided by an embodiment of the present invention are described in detail through specific embodiments and application scenarios.

[0068] Taking the BDS / LEO occultation detection of the Earth's atmosphere as an example, it means that the radio wave signal emitted by the BDS satellite is obscured by the Earth's atmosphere, and reaches the LEO satellite after being refracted by the Earth's atmosphere and ionosphere, which is also the limb observation of the BDS satellite. The received BDS signal contains information about the Earth's atmosphere and ionosphere, so the atmospheric and ionosphere profiles can be inverted through relevant scientific inversion methods. Occultation detection is that the frequency, phase and amplitude of the signal emitted by the navigation satellite will change after passing through the ionosphere and atmosphere. Through the inversion calculation of this change, information such as atmospheric temperature, humidity, air pressure and ionospheric electron density can be obtained, which makes up for the shortcomings of traditional meteorological observation methods.

[0069] Therefore, in the embodiment of the present application, in order to avoid the inversion error caused by excessive multipath error of the reference star, the reference star with the highest accuracy among all reference stars is obtained through multipath calculation.

[0070] Reference Figure 1 , Figure 1 A schematic flow chart of a method for selecting a reference star for an occultation is provided in an embodiment of the present invention. The method for selecting a reference star for an occultation comprises the following steps:

[0071] Step 101, obtaining a target time period corresponding to an occultation event, wherein the target time period is a start time and an end time corresponding to the occultation event;

[0072] It should be noted that in the embodiment of the present application, the occultation event refers to detection based on the occultation technology. Therefore, first, the occultation event for which a reference star selection is required is selected according to the user's selection. The occultation event has a start and end time. The start time corresponding to the occultation event is recorded as t1, and the end time is recorded as t2. Therefore, the target time period is the [t1, t2] time period.

[0073] Step 102, determining a candidate reference star according to a target time period corresponding to the occultation event;

[0074] It should be noted that, in the embodiment of the present application, after the occultation event is determined, all reference stars received by the receiver can be obtained, and their number can be recorded as the first number N.

[0075] Among them, the receiver is installed on the satellite during occultation observation. When it is determined that the GNSS satellite signal has not entered the occultation state, the receiver occultation unit does not receive the GNSS signal. When it is detected that the GNSS satellite signal is in the occultation state, the receiver samples and observes the GNSS satellite signal. When the satellite passes over the satellite ground station, the telemetry data can be transmitted to the satellite ground station. The satellite ground station can continue to transmit the data to the relevant data processing center, and then process it based on these data.

[0076] Further, determining the candidate reference star according to the target time period corresponding to the occultation event includes: judging whether there is valid observation quantity of the reference star in the target time period; if so, taking the reference star as the candidate reference star.

[0077] That is, in the embodiment of the present application, the candidate reference star can be determined based on whether there is valid observation quantity of the reference star corresponding to the occultation event in the target time period.

[0078] Therefore, after receiving the reference star and the first number sent by the receiver, it is possible to determine in turn whether each reference star is continuous in the target time period [t1, t2], that is, whether all observations are available in the target time period [t1, t2], and whether all observations are valid. The specific determination method is that among the observations in the corresponding time period, (1) the pseudorange observation is a valid value, (2) the carrier phase observation is a valid value, and (3) the signal-to-noise ratio is greater than a given threshold. The observations in the target time period [t1, t2] meet the above three conditions at the same time, and the observations are considered valid. If there are continuous observations in the target time period, the reference star is placed in the candidate reference star.

[0079] Specifically, if a reference star is continuous in the time period [t1, t2], the reference star will be placed in the candidate reference stars. If it is not continuous, the reference star will not be placed in the candidate reference stars. Finally, the total number of candidate reference stars is recorded as M (M≤N).

[0080] Step 103, obtaining the target frequency corresponding to the target observation frequency point;

[0081] Further, the acquiring a target frequency corresponding to a target observation frequency includes: receiving a target observation frequency sent by a user; and acquiring a target frequency corresponding to the target observation frequency according to the target observation frequency.

[0082] It should be noted that in the embodiment of the present application, after determining the alternative reference star, the target observation frequency point can be selected according to user needs, and after determining the target observation frequency point, the corresponding target frequency can be determined.

[0083] Step 104, acquiring multipath data corresponding to the candidate reference star in the target time period according to the target frequency;

[0084] It should be noted that in the embodiment of the present application, the alternative reference star needs to have at least the capability of dual-frequency observation of a single GNSS system.

[0085] After obtaining the target observation frequency selected by the user, the multipath data of the candidate reference star corresponding to the target time period is obtained according to the target frequency, that is, the multipath calculation results of any candidate reference star i at all times of the occultation event (target time period) are counted according to the target frequency to obtain the multipath data.

[0086] Step 105: Determine a target reference star corresponding to the occultation event according to the multipath data.

[0087] It should be noted that, in the embodiment of the present application, after the multipath data is obtained, the final target reference star can be determined according to the multipath data.

[0088] The multipath effect refers to the fact that when a receiver receives the direct signal transmitted by the satellite, it also receives the reflected signal from the ground objects around the station. The two signals interfere and superimpose, causing additional time delay or phase delay, which causes the observed value to deviate from the true value, resulting in the so-called multipath error. This interference delay effect caused by the satellite signal entering the receiver through multiple reflection paths is called the multipath effect.

[0089] Therefore, multipath data is needed to determine the size of the multipath error and then to determine the target reference star corresponding to the occultation event, that is, to obtain the reference star with the highest accuracy among all reference stars.

[0090] An embodiment of the present invention provides a method for selecting an occultation reference star, which obtains a target time period corresponding to an occultation event, wherein the target time period is the start time and the end time corresponding to the occultation event; determines an alternative reference star according to the target time period corresponding to the occultation event; obtains a target frequency corresponding to a target observation frequency point; obtains multipath data corresponding to the alternative reference star in the target time period according to the target frequency; and determines the target reference star corresponding to the occultation event according to the multipath data. In the embodiment of the present invention, by selecting a target reference star in an occultation event, firstly, a satellite continuously tracked during the occultation event is searched from positioning satellites to determine the alternative reference star, and then the multipath data of the satellites of these alternative reference stars during the entire occultation event are evaluated by a multipath estimation method, and then the target reference star is determined according to the multipath data. In this way, the reference star with the highest accuracy among all reference stars can be obtained, and the inversion error caused by the excessive multipath error of the reference star can be avoided. Moreover, when the target reference star is used to calculate the additional phase to invert the refractive index, the occultation inversion accuracy can be improved.

[0091] Reference Figure 2 , Figure 2 A schematic flow chart of another method for selecting a reference star for occultation provided by an embodiment of the present invention, the method for selecting a reference star for occultation comprising the following steps:

[0092] Step 201, obtaining a target time period corresponding to an occultation event, wherein the target time period is a start time and an end time corresponding to the occultation event;

[0093] Step 202, determining a candidate reference star according to a target time period corresponding to the occultation event;

[0094] Step 203, obtaining the target frequency corresponding to the target observation frequency point;

[0095] It should be noted that in the embodiment of the present application, the above steps 201-203 refer to the previous discussion and will not be repeated here.

[0096] Step 204, determining the pseudorange observation amount of the candidate reference star at any time and the carrier phase observation amount according to the target frequency;

[0097] Step 205, obtaining multipath data corresponding to each candidate reference star in the target time period through dual-frequency data, pseudorange observations, and carrier phase observations;

[0098] It should be noted that in the embodiment of the present application, the alternative reference star needs to have at least the capability of dual-frequency observation of a single GNSS system.

[0099] The satellite number is represented by i, and the frequency of the observation point is recorded as f. k, where k is the frequency point number. The pseudo-range observation value of the reference satellite frequency point k of satellite number i at time t is recorded as The carrier phase observation of reference satellite frequency point k of satellite number i at time t is recorded as

[0100] Therefore, the receiver receives the GNSS signal of the target frequency corresponding to the alternative reference star according to the target frequency and then calculates the pseudorange observation amount and the carrier phase observation amount of the alternative reference star at any time, and then calculates the multipath size of each frequency point through the dual-frequency data using the pseudorange observation amount and the carrier phase observation amount.

[0101] Furthermore, the multipath data corresponding to the candidate reference star in the target time period is obtained by the following formula:

[0102]

[0103]

[0104] In the above formulas 1 and 2, i represents the satellite number, k represents the observation frequency number, and f k represents the frequency of the observed frequency point, represents the pseudo-range observation of reference frequency point k of satellite number i at time t, represents the carrier phase observation of reference frequency point k of satellite number i at time t, and j is an arbitrary value of k.

[0105] It should be noted that the above formula 1 calculates the multipath data of the first frequency point corresponding to the alternative reference satellite in the target time period based on the first frequency point and the j-th frequency point, that is, the left side of the equal sign is the data of the first frequency point, and j representing the second frequency point must be greater than or equal to 2 and cannot be equal to 1, otherwise it will be repeated with the first frequency point.

[0106] The above formula 2 calculates the multipath data of the jth frequency point based on the first frequency point and the jth frequency point. Similarly, j cannot be equal to 1, otherwise it is equivalent to taking the data of two identical first frequency points for calculation.

[0107] In one embodiment, when j in the above formulas 1 and 2 is 2, then the multipath data of the first frequency point and the second frequency point are calculated based on the data of the first frequency point and the second frequency point respectively.

[0108] Step 206: Determine a target reference star corresponding to the occultation event according to the multipath data.

[0109] The embodiment of the present invention selects a target reference star during an occultation event, first searches for satellites that are continuously tracked during the occultation event from positioning satellites to determine candidate reference stars, then uses a multipath estimation method to evaluate multipath data of the candidate reference stars during the entire occultation event, and then determines the target reference star based on the multipath data. In this way, the reference star with the highest accuracy among all reference stars can be obtained, and the inversion error caused by excessive multipath error of the reference star can be avoided. In addition, when the target reference star is used to calculate the additional phase to invert the refractive index, the occultation inversion accuracy can be improved.

[0110] In addition, in the embodiment of the present application, the reference star error is obtained by calculating the reference star dual-frequency pseudorange and carrier phase observation to obtain multipath data, so that the reference star selection is more reliable and more accurate.

[0111] Reference Figure 3 , Figure 3 A schematic flow chart of another method for selecting a reference star for occultation provided by an embodiment of the present invention, the method for selecting a reference star for occultation comprising the following steps:

[0112] Step 301, obtaining a target time period corresponding to an occultation event, wherein the target time period is a start time and an end time corresponding to the occultation event;

[0113] Step 302, determining a candidate reference star according to a target time period corresponding to the occultation event;

[0114] Step 303, obtaining the target frequency corresponding to the target observation frequency point;

[0115] Step 304, acquiring multipath data corresponding to the candidate reference star in the target time period according to the target frequency;

[0116] It should be noted that in the embodiment of the present application, the above steps 301-304 refer to the previous discussion and will not be repeated here.

[0117] Step 305, performing mean processing on all multipath data corresponding to each candidate reference star in the target time period to obtain a multipath mean corresponding to each candidate reference star;

[0118] Step 306: Determine a target reference star corresponding to the occultation event according to the multipath mean.

[0119] It should be noted that in the embodiment of the present application, the mean multipath value of all candidate reference stars in the occultation event is calculated, and the user can make a selection based on the mean as needed, for example, select the candidate reference star with the smallest mean, thereby selecting the target reference star with the smallest error.

[0120] Specifically, the reference star frequency point is selected for judgment according to the user's needs. Assuming that the frequency point selected by the user is k, the multipath calculation results of a reference star i at all times of the occultation event are counted, and the average value is calculated. The average value calculation formula is as follows:

[0121]

[0122] In the above formula 3, i represents the reference satellite number, n represents the number of all observations of the occultation event at all times [t1, t2], and f k Indicates the selected frequency.

[0123] The embodiment of the present invention selects a target reference star during an occultation event, first searches for satellites that are continuously tracked during the occultation event from positioning satellites to determine candidate reference stars, then uses a multipath estimation method to evaluate multipath data of the candidate reference stars during the entire occultation event, and then determines the target reference star based on the multipath data. In this way, the reference star with the highest accuracy among all reference stars can be obtained, and the inversion error caused by excessive multipath error of the reference star can be avoided. In addition, when the target reference star is used to calculate the additional phase to invert the refractive index, the occultation inversion accuracy can be improved.

[0124] In addition, in the embodiment of the present application, by averaging all multipath data corresponding to each alternative reference star in the target time period, a multipath mean corresponding to each alternative reference star is obtained, and then the target reference star corresponding to the occultation event is determined according to the multipath mean. That is, the satellite with the smallest multipath value can be selected as the target reference star to avoid inversion errors caused by excessive multipath errors of the reference star.

[0125] Reference Figure 4 , Figure 4 A schematic flow chart of another method for selecting a reference star for occultation provided by an embodiment of the present invention, the method for selecting a reference star for occultation comprising the following steps:

[0126] Step 401, obtaining a target time period corresponding to an occultation event, wherein the target time period is a start time and an end time corresponding to the occultation event;

[0127] Step 402, determining a candidate reference star according to a target time period corresponding to the occultation event;

[0128] Step 403, obtaining the target frequency corresponding to the target observation frequency point;

[0129] Step 404, acquiring multipath data corresponding to the candidate reference star in the target time period according to the target frequency;

[0130] It should be noted that, in the embodiment of the present application, the above steps 401-404 refer to the previous discussion and will not be repeated here.

[0131] Step 405, performing standard deviation processing on all multipath data corresponding to the candidate reference star in the target time period to obtain a multipath standard deviation corresponding to each candidate reference star;

[0132] Step 406: Determine a target reference star corresponding to the occultation event according to the multipath standard deviation.

[0133] It should be noted that in the embodiment of the present application, the standard deviation of the multipath values ​​of all the alternative reference stars in the occultation event is calculated, and the user can make a selection based on the standard deviation as needed, for example, select the alternative reference star with the smallest standard deviation, thereby selecting the target reference star with the smallest error.

[0134] Specifically, the reference star frequency point is selected for judgment according to the user's needs. Assuming that the frequency point selected by the user is k, the multipath calculation results of a reference star i at all times of the occultation event are counted, and the standard deviation is calculated. The standard deviation calculation formula is as follows:

[0135]

[0136] In the above formula 4, i represents the reference satellite number, n represents the number of all observations of the occultation event at all times [t1, t2], and f k Indicates the selected frequency.

[0137] The embodiment of the present invention selects a target reference star during an occultation event, first searches for satellites that are continuously tracked during the occultation event from positioning satellites to determine candidate reference stars, then uses a multipath estimation method to evaluate multipath data of the candidate reference stars during the entire occultation event, and then determines the target reference star based on the multipath data. In this way, the reference star with the highest accuracy among all reference stars can be obtained, and the inversion error caused by excessive multipath error of the reference star can be avoided. In addition, when the target reference star is used to calculate the additional phase to invert the refractive index, the occultation inversion accuracy can be improved.

[0138] In addition, in the embodiment of the present application, the standard deviation of the multipath data corresponding to the alternative reference star in the target time period is processed, and the multipath standard deviation corresponding to each alternative reference star is obtained; the target reference star corresponding to the occultation event is determined according to the multipath standard deviation, that is, the satellite with the smallest multipath standard deviation can be selected as the target reference star, avoiding the inversion error caused by excessive multipath error of the reference star.

[0139] In addition, in another embodiment, the multipath mean and multipath standard deviation corresponding to each candidate reference star may be obtained respectively, and the mean and standard deviation may be comprehensively considered to make a selection, thereby selecting a reference star with the smallest error.

[0140] The present invention also relates to a device for selecting a reference star for occultation, the device block diagram of which is shown in FIG. Figure 5As shown, including:

[0141] A first acquisition module 501 is used to acquire a target time period corresponding to an occultation event, wherein the target time period is a start time and an end time corresponding to the occultation event;

[0142] A first determination module 502 is used to determine a candidate reference star according to a target time period corresponding to the occultation event;

[0143] The second acquisition module 503 is used to acquire the target frequency corresponding to the target observation frequency point;

[0144] A third acquisition module 504 is used to acquire multipath data corresponding to the candidate reference star in the target time period according to the target frequency;

[0145] The second determination module 505 is configured to determine a target reference star corresponding to the occultation event according to the multipath data.

[0146] Optionally, the first determining module includes:

[0147] The first determination submodule is used to determine whether there is a valid observation quantity of the reference star in the target time period;

[0148] The second determining submodule is configured to, if yes, use the reference star as a candidate reference star.

[0149] Optionally, the second acquisition module includes:

[0150] The receiving submodule is used to receive the target observation frequency sent by the user;

[0151] The acquisition submodule is used to acquire the target frequency corresponding to the target observation frequency point according to the target observation frequency point.

[0152] Optionally, the third acquisition module includes:

[0153] A third determination submodule is used to determine the pseudorange observation amount of the candidate reference star at any time and the carrier phase observation amount according to the target frequency;

[0154] The multipath data acquisition submodule is used to acquire the multipath data corresponding to each candidate reference star in the target time period through dual-frequency data, pseudo-range observations, and carrier phase observations.

[0155] Optionally, the second determining module includes:

[0156] A multipath mean value acquisition module is used to perform mean processing on all multipath data corresponding to each candidate reference star in the target time period to obtain a multipath mean value corresponding to each candidate reference star;

[0157] The fourth determination submodule is used to determine the target reference star corresponding to the occultation event according to the multipath mean.

[0158] Optionally, the second determining module includes:

[0159] A multipath standard deviation acquisition module, used to perform standard deviation processing on all multipath data corresponding to the candidate reference star in the target time period to obtain a multipath standard deviation corresponding to each candidate reference star;

[0160] The fifth determination submodule is used to determine the target reference star corresponding to the occultation event according to the multipath standard deviation.

[0161] The embodiment of the present invention selects a target reference star during an occultation event, first searches for satellites that are continuously tracked during the occultation event from positioning satellites to determine candidate reference stars, then uses a multipath estimation method to evaluate multipath data of the candidate reference stars during the entire occultation event, and then determines the target reference star based on the multipath data. In this way, the reference star with the highest accuracy among all reference stars can be obtained, and the inversion error caused by excessive multipath error of the reference star can be avoided. In addition, when the target reference star is used to calculate the additional phase to invert the refractive index, the occultation inversion accuracy can be improved.

[0162] As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0163] The present invention also relates to a storage medium storing a computer program, wherein when the computer program is executed by a processor, the steps of the method for selecting a reference star for occultation are implemented as described in the first aspect.

[0164] The embodiment of the present invention further provides an electronic device, such as Figure 6 As shown, it includes a processor 601, a communication interface 602, a memory 603 and a communication bus 604, wherein the processor 601, the communication interface 602, and the memory 603 communicate with each other through the communication bus 604.

[0165] Memory 603, used for storing computer programs;

[0166] The processor 601 is used to execute the program stored in the memory 603 to implement the following steps:

[0167] Obtain a target time period corresponding to the occultation event, wherein the target time period is the start time and end time corresponding to the occultation event;

[0168] Determining a candidate reference star according to a target time period corresponding to the occultation event;

[0169] Get the target frequency corresponding to the target observation frequency point;

[0170] Acquire multipath data corresponding to the candidate reference star in the target time period according to the target frequency;

[0171] A target reference star corresponding to the occultation event is determined according to the multipath data.

[0172] The communication bus mentioned in the above terminal can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The communication bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus.

[0173] The communication interface is used for communication between the above terminal and other devices.

[0174] The memory may include a random access memory (RAM) or a non-volatile memory, such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the aforementioned processor.

[0175] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0176] In another embodiment provided by the present invention, a computer-readable storage medium is also provided, in which instructions are stored. When the computer-readable storage medium is run on a computer, the computer executes the method for selecting a reference star for occultation described in any of the above embodiments.

[0177] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integration. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state hard disk Sol Identification State Disk (SSD)), etc.

[0178] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0179] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0180] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A method for selecting an occultation reference star, characterized in that: The method comprises: Obtain a target time period corresponding to the occultation event, wherein the target time period is the start time and end time corresponding to the occultation event; Determining a candidate reference star according to a target time period corresponding to the occultation event; Get the target frequency corresponding to the target observation frequency point; Acquire multipath data of the candidate reference star corresponding to the target time period according to the target frequency; Determine a target reference star corresponding to the occultation event according to the multipath data; The multipath data corresponding to the candidate reference star in the target time period is obtained by the following formula: In the above formula, i represents the satellite number, k represents the observation frequency number, and f k represents the frequency of the observed frequency point, represents the pseudo-range observation of reference frequency point k of satellite number i at time t, represents the carrier phase observation of reference frequency point k of satellite number i at time t, and j is an arbitrary value of k.

2. The method according to claim 1, characterized in that Determining the candidate reference star according to the target time period corresponding to the occultation event comprises: Determine whether there is valid observation quantity of the reference star in the target time period; If so, the reference star is used as an alternative reference star.

3. The method according to claim 1, characterized in that The step of obtaining the target frequency corresponding to the target observation frequency point includes: Receive the target observation frequency sent by the user; A target frequency corresponding to the target observation frequency point is obtained according to the target observation frequency point.

4. The method according to claim 1, characterized in that: The acquiring, according to the target frequency, the multipath data corresponding to the candidate reference star in the target time period comprises: Determine the pseudorange observation amount of the candidate reference star at any time and the carrier phase observation amount according to the target frequency; The multipath data corresponding to each candidate reference star in the target time period is obtained through dual-frequency data, pseudo-range observations, and carrier phase observations.

5. The method according to claim 1, characterized in that Determining the target reference star corresponding to the occultation event according to the multipath data comprises: Performing mean processing on all multipath data corresponding to each candidate reference star in the target time period to obtain a multipath mean corresponding to each candidate reference star; A target reference star corresponding to the occultation event is determined according to the multipath mean.

6. The method according to claim 1, characterized in that Determining the target reference star corresponding to the occultation event according to the multipath data comprises: Performing standard deviation processing on all multipath data corresponding to the candidate reference star in the target time period to obtain a multipath standard deviation corresponding to each candidate reference star; A target reference star corresponding to the occultation event is determined according to the multipath standard deviation.

7. An occultation reference star selection device, characterized in that: The device comprises: A first acquisition module is used to acquire a target time period corresponding to the occultation event, wherein the target time period is a start time and an end time corresponding to the occultation event; A first determination module is used to determine a candidate reference star according to a target time period corresponding to the occultation event; The second acquisition module is used to acquire the target frequency corresponding to the target observation frequency point; A third acquisition module is used to acquire multipath data corresponding to the candidate reference star in the target time period according to the target frequency; A second determination module is used to determine the target reference star corresponding to the occultation event according to the multipath data; The third acquisition module is specifically used to acquire the multipath data corresponding to the candidate reference star in the target time period by using the following formula: In the above formula, i represents the satellite number, k represents the observation frequency number, and f k represents the frequency of the observed frequency point, represents the pseudo-range observation of reference frequency point k of satellite number i at time t, represents the carrier phase observation of reference frequency point k of satellite number i at time t, and j is an arbitrary value of k.

8. The device according to claim 7, characterized in that The first determining module comprises: The first determination submodule is used to determine whether there is a valid observation quantity of the reference star in the target time period; The second determining submodule is configured to, if yes, use the reference star as a candidate reference star.

9. The device according to claim 7, characterized in that The second acquisition module includes: The receiving submodule is used to receive the target observation frequency sent by the user; The acquisition submodule is used to acquire the target frequency corresponding to the target observation frequency point according to the target observation frequency point.

10. The device according to claim 7, characterized in that The third acquisition module includes: A third determination submodule is used to determine the pseudorange observation amount of the candidate reference star at any time and the carrier phase observation amount according to the target frequency; The multipath data acquisition submodule is used to acquire the multipath data corresponding to each candidate reference star in the target time period through dual-frequency data, pseudo-range observations, and carrier phase observations.

11. The device according to claim 7, characterized in that The second determining module comprises: A multipath mean value acquisition module is used to perform mean processing on all multipath data corresponding to each candidate reference star in the target time period to obtain a multipath mean value corresponding to each candidate reference star; The fourth determination submodule is used to determine the target reference star corresponding to the occultation event according to the multipath mean.

12. The device according to claim 7, characterized in that The second determining module comprises: A multipath standard deviation acquisition module, used to perform standard deviation processing on all multipath data corresponding to the candidate reference star in the target time period to obtain a multipath standard deviation corresponding to each candidate reference star; The fifth determination submodule is used to determine the target reference star corresponding to the occultation event according to the multipath standard deviation.

13. An electronic device, characterized in that: include: processor; a memory for storing processor-executable instructions; The processor is configured to execute the instructions to implement the occultation reference star selection method as described in claims 1-6.

14. A computer storage medium, when the instructions in the storage medium are executed by a processor of a mobile terminal, the mobile terminal is enabled to execute the method for selecting a reference star for occultation according to claims 1-6.

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