Station site correction method using optical angle measurement and precise ephemeris data

Abstract

The present disclosure provides a station site correction method using optical angle measurement and precise ephemeris data, belonging to the field of space object observation technology. Ground-based optical telescopes primarily obtain angle measurement data by capturing sunlight reflected from space objects. This angle measurement data is primarily used for orbit determination to obtain the orbital motion parameters of space objects and achieve orbit prediction. This method uses an optical telescope to perform angle measurement observations on high-precision ephemeris targets and corrects station coordinates. Experimental results have shown that the corrected coordinates using this method significantly improve the accuracy of angle measurement calibration. This method can correct the site coordinates of ground-based stations and improve the accuracy of optical angle measurement data.

Description

Technical Field

[0001] The present disclosure relates to the technical field of space object observation, and in particular to a site correction method using optical angle measurement and precise ephemeris data. Background Art

[0002] Over the past 60 years, the space industry has flourished, but this has also introduced hundreds of millions of space objects into outer space. These include space debris and artificial satellites, with space debris constituting the largest number. Space debris larger than 1 centimeter can cause severe damage to spacecraft in orbit, while debris smaller than 1 centimeter can also degrade spacecraft system performance. Currently, there are over 30,000 pieces of debris larger than 10 centimeters, nearly a million larger than 1 centimeter, and hundreds of millions of millimeter-sized debris. Space debris is most densely populated in key, commonly used orbits, such as Low Earth Orbit (LEO) at 500-1000 km and Geosynchronous Orbit (GEO) at 36,000 km. All confirmed spacecraft collisions have occurred in these regions. Disintegration and collision debris are the primary drivers of the growing space debris population. For example, the 2009 US-Russian satellite collision produced nearly 3,000 trackable pieces of debris. Furthermore, the launch of small satellites and large constellations is booming. The number of small satellite launch plans announced by countries around the world has reached nearly 100,000. Frequent space activities and the continuous addition of a large number of new spacecraft have led to a continuous growth in the number of space objects, which will inevitably increase the risk of collisions between spacecraft in orbit and pose severe challenges to the security of space assets.

[0003] Public content

[0004] The main purpose of the present invention is to provide a station site correction method using optical angle measurement and precise ephemeris data, aiming to solve the technical problems of low accuracy of traditional optical angle measurement data and inability to correct the site coordinates of ground-based stations.

[0005] To achieve the above objectives, the present disclosure provides a method for correcting a station location using optical angle measurement and precise ephemeris data, comprising the following steps:

[0006] Step S10: obtaining precise ephemeris data of the space object;

[0007] Step S20: Calculate the conversion value Y of the precise ephemeris data based on the precise ephemeris data * (t i );

[0008] Step S30: Obtain the observed value Y(t i ), and calculate the observed value Y(t i ) and the conversion value Y of the precise ephemeris data * (t i ) between the residual y(t i );

[0009] Step S40: establishing a normalized equation for the position correction of the ground-fixed coordinate system of the measuring station, and solving the position correction of the ground-fixed coordinate system of the measuring station;

[0010] Step S50: Correct the position vector of the ground-fixed coordinate system of the survey station, and repeat steps S20 to S40 using the corrected position vector of the ground-fixed coordinate system of the survey station until the position correction amount of the ground-fixed coordinate system of the survey station converges to the required accuracy range.

[0011] Optionally, the conversion value Y of the precise ephemeris data is calculated based on the precise ephemeris data. * (t i ) steps include:

[0012] Step S201: Align the precise ephemeris data with the observation data, and use the cubic spline difference method to obtain the time series t i The corresponding position information R(t i ), i=1, 2, 3,..., N;

[0013] Step S202: R(t i ), i=1, 2, 3, N are converted into corresponding right ascension-declination angle data.

[0014] Optionally, calculate the conversion value Y of the precise ephemeris data * (t i ) is as follows:

[0015]

[0016]

[0017] Where r = M ITRS2GCRS( t)R,r e =M ITRS2GCRS (t)R e ,r,r e are the position vectors of the space object and the station in the geocentric celestial coordinate system, R, R e are the position vectors of the space object and the station in the Earth-fixed coordinate system, ITRS2GCRS (t) is the transformation matrix from the Earth-fixed coordinate system to the Earth-centered celestial coordinate system.

[0018] Optionally, the steps of establishing a normalized equation for the position correction of the ground-fixed coordinate system of the measuring station and solving the position correction of the ground-fixed coordinate system of the measuring station include:

[0019] Step S401: Establish observation value Y(t i ) with respect to the position vector of the station's ground-fixed coordinate system, the partial derivative matrix H(t i );

[0020] Step S402: accumulating the partial derivative matrix to obtain a normalized equation for solving the position correction of the ground-fixed coordinate system of the measuring station;

[0021] Step S403: Calculate the position correction of the ground-fixed coordinate system of the measuring station.

[0022] Optionally, the observed value Y(t i ), partial derivative matrix H(t i ) satisfies the following relationship:

[0023]

[0024] Y(t i )=(α i , δ i ) T

[0025] ρ i =|r obs (t i )|

[0026] Optionally, the normalized equation of the position correction of the station's ground-fixed coordinate system satisfies the following relationship:

[0027]

[0028] The present disclosure provides a station site correction method using optical angle measurement and precise ephemeris data, belonging to the field of space object observation technology. Ground-based optical telescopes primarily obtain angle measurement data by capturing sunlight reflected from space objects. This angle measurement data is primarily used for orbit determination to obtain the orbital motion parameters of space objects and achieve orbit prediction. This method uses an optical telescope to perform angle measurement observations on high-precision ephemeris targets and corrects station coordinates. Experimental results have shown that the corrected coordinates using this method significantly improve the accuracy of angle measurement calibration. This method can correct the site coordinates of ground-based stations and improve the accuracy of optical angle measurement data. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0030] Figure 1 A flow chart of an embodiment of a method for correcting a station address using optical angle measurement and precise ephemeris data provided by the present invention;

[0031] Figure 2A flow chart of an embodiment of a method for correcting a station address using optical angle measurement and precise ephemeris data provided by the present invention;

[0032] Figure 3 The present invention provides a flow chart of an embodiment of a method for correcting a station location using optical angle measurement and precise ephemeris data.

[0033] The realization of the objectives, functional features and advantages of the present disclosure will be further explained with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present disclosure in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present disclosure without making any creative efforts shall fall within the scope of protection of the present disclosure.

[0035] It should be noted that if directional indications are involved in the embodiments of the present disclosure, the directional indications are only used to explain the relative positional relationship, movement status, etc. between the components under a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0036] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present disclosure, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme in which A and B are satisfied at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present disclosure.

[0037] The present invention provides a method for correcting a station address using optical angle measurement and precise ephemeris data, comprising the following steps:

[0038] Step S10: obtaining precise ephemeris data of the space object;

[0039] Step S20: Calculate the conversion value Y of the precise ephemeris data based on the precise ephemeris data * (t i );

[0040] Step S30: Obtain the observed value Y(t i ), and calculate the observed value Y(t i ) and the conversion value Y of the precise ephemeris data * (t i ) between the residual y(t i );

[0041] Step S40: establishing a normalized equation for the position correction of the ground-fixed coordinate system of the measuring station, and solving the position correction of the ground-fixed coordinate system of the measuring station;

[0042] Step S50: Correct the position vector of the ground-fixed coordinate system of the survey station, and repeat steps S20 to S40 using the corrected position vector of the ground-fixed coordinate system of the survey station until the position correction amount of the ground-fixed coordinate system of the survey station converges to the required accuracy range.

[0043] Specifically, an optical telescope is used to track and observe space objects with precise ephemeris data, such as GNSS satellites. The right ascension-declination angle data is calculated to obtain Y(t i ), i = 1, 2, 3, ..., N. The precise ephemeris is interpolated to the observation time, and the cubic spline difference method can be used to obtain the time series t i The corresponding position information R(t i ), i = 1, 2, 3, ..., N. The given example observation data and the corresponding precise ephemeris are shown in the table:

[0044] Table 1 Observation data and precise ephemeris of target 1:

[0045]

[0046] Table 2 Observation data and precise ephemeris of target 2:

[0047]

[0048] The initial station coordinates are: R e =(-133578329, 4872021.92, 3882636.81)

[0049] R(t i ), i = 1, 2, 3, ..., N is converted to the corresponding right ascension-declination angle data. The formula is as follows:

[0050]

[0051]

[0052] r=M ITRS2GCRS (t)R,r e =M ITRR2GCRS (t)R e

[0053] where r, r e are the position vectors of the space object and the station in the geocentric celestial coordinate system. R, R e are the position vectors of the space object and the station in the Earth-fixed coordinate system respectively. ITRS2GCRs (t) is the transformation matrix from the Earth-fixed coordinate system to the Geocentric Celestial coordinate system. The specific calculation method can be found in (IERS Conventions (2010)). It mainly uses the calculation of three transformation matrices: precession, nutation, and polar motion.

[0054] Calculate the actual observation value Y(t i ) and the precise ephemeris conversion value Y * (t i ) between the residual y(t i ).

[0055] Calculate the partial derivative matrix of the observation value with respect to the position vector of the station's ground-fixed coordinate system. Use the following formula:

[0056]

[0057] Y(t i )=(α i , δ i ) T

[0058] ρ i =|r obs (t i )|

[0059] The normalized equation for calculating the position correction of the ground-fixed coordinate system of the measuring station is obtained by accumulation.

[0060]

[0061] Solve the position correction of the ground-fixed coordinate system of the measuring station:

[0062]

[0063] Step 8: Correct the position vector of the ground-fixed coordinate system of the measuring station:

[0064] R e =R e +dR e

[0065] Repeat steps S20 to S40 using the corrected station ground-fixed coordinate system position vector until dR e Converge to the required accuracy range.

[0066] The example given here has three iterations. The three iteration stations are located at positions R in the ground-fixed coordinate system.e , the corrected observation residual y(t i ) are shown in the following table:

[0067] Table 3 Iterative convergence process

[0068]

[0069] In summary, it can be seen from the above technical solutions that the site correction method using optical angle measurement and precise ephemeris data disclosed in the present invention has at least one or part of the following beneficial effects:

[0070] (1) The matching accuracy (RMS) between the actual observation values ​​after the correction of the station coordinates and the observation values ​​converted from the high-precision ephemeris is significantly improved, which shows that the correction effect of the station coordinates is obvious.

[0071] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present disclosure. It should be understood that the above are only specific embodiments of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure should be included in the scope of protection of the present disclosure.

Claims

1. A station address correction method using optical angle measurement and precise ephemeris data, characterized in that: The steps include: Step S10: obtaining precise ephemeris data of the space object; Step S20: Calculate the conversion value of the precise ephemeris data based on the precise ephemeris data ; Step S30: Use an optical telescope to track and observe space objects with precise ephemeris data, calculate the right ascension-declination angle data, and obtain the observation value , and calculate the observed value Conversion value with precise ephemeris data The residual between ; Step S40: establishing a normalized equation for the position correction of the ground-fixed coordinate system of the measuring station, and solving the position correction of the ground-fixed coordinate system of the measuring station; Step S50: Correct the position vector of the ground-fixed coordinate system of the survey station, and repeat steps S20 to S40 using the corrected position vector of the ground-fixed coordinate system of the survey station until the position correction amount of the ground-fixed coordinate system of the survey station converges to the required accuracy range.

2. The station address correction method using optical angle measurement and precise ephemeris data according to claim 1, characterized in that: Calculate the conversion value of precise ephemeris data based on precise ephemeris data The steps include: Step S201: Align the precise ephemeris data with the observation data, and use the cubic spline difference method to obtain the time series. Corresponding position information in the earth-fixed coordinate system ; Step S202: Convert to corresponding right ascension-declination angle data.

3. The station address correction method using optical angle measurement and precise ephemeris data as claimed in claim 2, characterized in that: Calculate the conversion value of precise ephemeris data The formula is as follows: in, , are the position vectors of the space object and the station in the geocentric celestial coordinate system, are the position vectors of the space object and the station in the Earth-fixed coordinate system, It is the transformation matrix from the Earth-fixed coordinate system to the Geocentric Celestial coordinate system.

4. The station address correction method using optical angle measurement and precise ephemeris data as claimed in claim 3, characterized in that: The steps of establishing the normalized equation for the position correction of the ground-fixed coordinate system of the measuring station and solving the position correction of the ground-fixed coordinate system of the measuring station include: Step S401: Create observation values Partial derivative matrix of the position vector of the station's ground-fixed coordinate system ; Step S402: accumulating the partial derivative matrix to obtain a normalized equation for solving the position correction of the ground-fixed coordinate system of the measuring station; Step S403: Calculate the position correction of the ground-fixed coordinate system of the measuring station.

5. The method for station address correction using optical angle measurement and precise ephemeris data as claimed in claim 4, characterized in that: Observations , partial derivative matrix Satisfies the following relationship: 。 6. The method for correcting the station location using optical angle measurement and precise ephemeris data according to claim 4, wherein the measurement The normalized equation of the position correction of the station ground-fixed coordinate system satisfies the following relationship: 。

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