Method and device for calibrating test error of VICTS antenna beam pointing

Abstract

The invention discloses a test error calibration method and device for the beam pointing of a VICTS antenna, and belongs to the field of satellite communication, and the method comprises the steps: installing the VICTS antenna in a compact field, and carrying out the beam pointing test; testing the beam direction of the symmetrical side of the azimuth plane of the antenna body at a certain antenna plane included angle; calculating the angle of the normal of the antenna surface deviating from the plane wave coming direction of the compact range when the compact range turntable is in the zero position; calculating the angle value of the antenna surface deviating from the vertical direction; calculating a beam azimuth angle correction value corresponding to any beam direction; and calculating a wave beam off-axis angle correction value corresponding to any wave beam direction. According to the invention, the problem that the beam pointing test is inaccurate due to the installation error when the beam pointing of the existing VICTS antenna is tested in a compact range darkroom is solved.

Description

Technical Field

[0001] The present invention relates to the field of satellite communication technology, and more specifically, to a method and device for calibrating a test error of a VICTS antenna beam pointing. Background Art

[0002] In recent years, VICTS antennas have been increasingly used in the field of satellite communications due to their low profile, high scanning efficiency, high reliability and low cost. Beam pointing test is the technical basis for the antenna's satellite communication. The antenna's beam pointing test data is used to guide the antenna beam to accurately align with the satellite.

[0003] At present, the beam pointing of VICTS antennas is generally tested using planar near-field and spherical near-field. However, these two test fields require the full spatial beam pointing of the antenna to be tested, which results in low test efficiency and is prone to installation errors and near-to-far field conversion errors. There are many error sources, and it is difficult to obtain accurate beam pointing test results through correction. Compact fields have been widely used in antenna electrical performance index testing due to their simple composition, no need for near-to-far field conversion, high test efficiency, and low cost. For VICTS antennas, compact fields can be used for targeted beam pointing tests to improve test efficiency and accuracy.

[0004] When performing beam pointing tests in a compact field, it is necessary to record the rotation angle of the antenna body and the rotation angle of the azimuth turntable as the test results of beam pointing. However, these two angles are greatly affected by the antenna installation error. For beams near the antenna normal, a small installation error will cause a test error of tens of degrees. The installation error mainly includes the angle value of the antenna surface normal deviating from the compact field azimuth zero, and the angle value of the antenna surface deviating from the vertical direction.

[0005] Due to the inevitable errors in the antenna installation structure, the test results of the beam pointing test greatly affect the accuracy of the antenna pointing to the satellite, making it impossible for the antenna system to stably track the satellite under dynamic conditions, thereby failing to achieve stable communication. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method and device for calibrating the test error of the beam pointing of a VICTS antenna, so as to solve the problem of inaccurate beam pointing test caused by installation error when the existing VICTS antenna is tested in a compact field darkroom.

[0007] The object of the present invention is achieved through the following solutions:

[0008] A VICTS antenna beam pointing test error calibration method comprises the following steps:

[0009] S1, install the VICTS antenna in the compact field and perform beam pointing test;

[0010] S2, testing the beam pointing direction on the symmetrical side of the antenna body azimuth plane when a certain antenna surface angle is tested;

[0011] S3, calculate the angle of the antenna surface normal line deviating from the direction of the compact field plane wave when the compact field turntable is in zero position;

[0012] S4, calculate the angle value of the antenna surface deviating from the vertical direction;

[0013] S5, calculating the beam azimuth correction value corresponding to the arbitrary beam pointing;

[0014] S6, calculating the beam off-axis angle correction value corresponding to the arbitrary beam pointing.

[0015] Further, in step S1, the VICTS antenna is installed in a compact field and a beam pointing test is performed, which specifically includes the following sub-steps:

[0016] S11, install the VICTS antenna: install the antenna base on the side of the bracket, fix the bottom of the bracket on the azimuth turntable in the compact field, and align the normal of the antenna surface with the direction of the plane wave of the compact field; the angle of the normal of the antenna surface deviating from the direction of the plane wave of the compact field when the turntable of the compact field is zero due to installation error is α, and the angle of the antenna surface deviating from the vertical direction is β;

[0017] S12, test beam pointing: beam azimuth Data relationship with the antenna surface angle δ The data relationship between the beam off-axis angle θ and the antenna surface angle δ is θ=g(δ), where the antenna surface angle δ represents the angle of rotation of the antenna radiation layer relative to the feed layer, and counterclockwise is positive;

[0018] For a specified antenna plane angle δ, the antenna beam is pointed in the horizontal plane by rotating the entire antenna body, and the antenna beam is aligned with the direction of the plane wave of the compact field by rotating the compact field azimuth turntable. At this time, the rotation angle of the antenna body is the beam azimuth. The rotation angle of the turntable is the beam off-axis angle θ; and by fine-tuning The antenna gain maximum point is found by using θ and θ to determine the best beam azimuth and off-axis angle test accuracy.

[0019] Further, in step S2, the beam pointing of the symmetrical side of the antenna body azimuth plane when testing a certain antenna surface angle specifically includes the following sub-steps: for a certain antenna surface angle δ0, according to the test result of S1, its beam azimuth angle is The off-axis angle is θ0 = g(δ0); then rotate the antenna body 180 degrees and find the antenna body rotation angle corresponding to the maximum gain through fine-tuning And the rotation angle of the compact turntable

[0020] Further, in step S3, the calculation of the angle of the antenna surface normal line deviating from the direction of the compact field plane wave when the compact field turntable is in zero position specifically includes the following sub-steps: according to the test result of step S2, the off-axis angle correction value is obtained: The off-axis angle correction value is used for the beam pointing corresponding to any positive angle of the antenna surface, and the off-axis angle θ′=θ-α after the first correction is obtained.

[0021] Furthermore, in step S4, the calculating of the angle value of the antenna plane deviating from the vertical direction specifically includes the following sub-steps:

[0022] According to the test results of S2, when the antenna surface angle is δ0, the beam azimuth deviation caused by the installation error Define the antenna coordinate system as Oxyz, the normal direction of the antenna surface is the y-axis, the vertical direction is the z-axis, and the x-axis is determined by the right-hand rule; define the antenna coordinate system rotated by the error angle β as Ox′y′z′, and the rotation matrix corresponding to the angle β is R z (β); From S3, the angle δ0 corresponds to the corrected off-axis angle θ′0, and the coordinate of this direction in the coordinate system Oxyz is A, so the representation of A in the coordinate system Ox′y′z′ is A′=R x (β)A; here:

[0023] but

[0024] Among them, sβ represents sin(β), cβ represents cos(β), and so on;

[0025] At this time, the angle between the projection of A′ on the Ox′z′ plane and Ox′ is the beam azimuth offset. Right now:

[0026]

[0027] Thus, we can infer

[0028] Further, in step S5, the calculating of the beam azimuth correction value corresponding to the arbitrary beam pointing specifically includes the following sub-steps:

[0029] According to step S3, the beam off-axis angle θ corresponding to any antenna surface angle δ is obtained ′ , according to the corresponding beam azimuth offset in step S4 Then the corrected beam azimuth is:

[0030]

[0031] Further, in step S6, the calculating of the beam off-axis angle correction value corresponding to the arbitrary beam pointing specifically includes the following sub-steps:

[0032] According to step S4, the off-axis angle of the vector A′ in the coordinate system Ox′y′z′ is the actual off-axis angle of the beam, that is, the corrected off-axis angle of the beam is:

[0033]

[0034] A VICTS antenna beam pointing test error calibration device comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is loaded by the processor, any of the above methods is executed.

[0035] The beneficial effects of the present invention include:

[0036] (1) The present invention uses a compact field to implement the test of the VICTS antenna beam pointing, and the test efficiency is high.

[0037] (2) Based on the original test data, the present invention only tests one additional pointing state, and can obtain the correction values ​​of all pointing states, and almost no additional darkroom test cost is added.

[0038] (3) The present invention greatly improves the beam pointing test accuracy of the VICTS antenna by calibrating the test data, and further improves the stability and reliability of the satellite communication antenna system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0040] Figure 1 Flow chart of a beam pointing test error calibration method for a VICTS antenna in an embodiment of the present invention;

[0041] Figure 2 Schematic diagram of a compact field test scenario of a VICTS antenna in an embodiment of the present invention;

[0042] Figure 3 Schematic diagram of installation error sources of the VICTS antenna when the azimuth turntable is at zero position in an embodiment of the present invention;

[0043] Figure 4 Schematic diagram of the coordinate system of the VICTS antenna in an embodiment of the present invention. DETAILED DESCRIPTION

[0044] All features disclosed in all embodiments in this specification, or steps in all methods or processes implicitly disclosed, except for mutually exclusive features and / or steps, can be combined and / or expanded or replaced in any manner.

[0045] The specific implementation process of the present invention is as follows:

[0046] In a preferred embodiment of the present invention, Figure 1 As shown, a beam pointing test error calibration method for a VICTS antenna is proposed, comprising the following steps:

[0047] S1, install the VICTS antenna in the compact field and perform beam pointing test. Figure 2 The figure shows a schematic diagram of the compact field test scenario of the VICTS antenna. The VICTS antenna is installed by installing the antenna base on the side of a bracket (such as a wooden frame), and the bottom of the wooden frame is fixed on an azimuth turntable in the compact field, so that the normal of the antenna surface is aligned with the direction of the plane wave in the compact field. Figure 3 The figure shows the installation error source of the VICTS antenna when the azimuth turntable is at zero position, where the angle at which the normal of the antenna surface deviates from the direction of the compressed field plane wave is α, and the angle at which the antenna surface deviates from the vertical direction is β.

[0048] Beam pointing tests include beam azimuth Data relationship with the antenna surface angle δ The data relationship between the beam off-axis angle θ and the antenna surface angle δ is θ=g(δ), where the antenna surface angle δ represents the angle of rotation of the antenna radiation layer relative to the feeding layer, and counterclockwise is positive.

[0049] The test method is to rotate the entire antenna body to point the antenna beam in the horizontal plane for a specified antenna plane angle δ, and to rotate the compact field azimuth turntable to align the antenna beam with the compact field plane wave. At this time, the rotation angle of the antenna body is the beam azimuth. The turntable rotation angle is the beam off-axis angle θ.

[0050] The test accuracy of the beam azimuth and off-axis angle depends on the accuracy of the antenna beam pointing to the plane wave of the compact field, which can be adjusted by fine-tuning The maximum point of antenna gain is found by θ and θ, and the beam pointing test result at this time is most accurate.

[0051] After the beam pointing test is performed according to the above method, some original test data are obtained as shown in Table 1:

[0052] Table 1

[0053]

[0054] S2, testing the beam pointing direction of the symmetrical side of the antenna body azimuth when a certain antenna surface angle is selected. Specifically, a certain antenna surface angle δ0 = 36 is selected. According to the test results of S1, it can be known that its beam azimuth angle is The off-axis angle is θ0 = g(36) = 45.2; then rotate the antenna body 180 degrees, and find the antenna body rotation angle corresponding to the maximum gain according to the S1 test method. And the rotation angle of the compact turntable

[0055] S3, calculate the angle α that the normal line of the antenna surface deviates from the direction of the plane wave of the compact field when the compact field turntable is in zero position. Specifically, according to the test results of S2, the off-axis angle correction value is obtained: Apply this off-axis angle correction to the beam pointing corresponding to any positive angle of the antenna surface, and obtain the first corrected off-axis angle θ ′ =θ+2.8.

[0056] S4, calculate the angle value β of the antenna surface from the vertical direction. Specifically, according to the test results of S2, when the antenna surface angle is δ0=36, the beam azimuth deviation caused by the installation error like Figure 4 The figure shows the coordinate system of the VICTS antenna. The antenna coordinate system is defined as Oxyz. The normal direction of the antenna surface is the y-axis, the vertical direction is the z-axis, and the x-axis is determined by the right-hand rule. The antenna coordinate system rotated by the error angle β is Ox′y′z′. At this time, the rotation matrix corresponding to the angle β is R x (β). From S3, it can be obtained that when the angle δ0=36, the corresponding corrected off-axis angle is θ′0=48. The coordinate of this direction in the coordinate system Oxyz is A, so the representation of A in the coordinate system Ox′y′z′ is A′=R x (β)A. Here:

[0057]

[0058] where sβ represents sin(β), cβ represents cos(β), and so on.

[0059] At this time, the angle between the projection of A′ on the Ox′z′ plane and Ox′ is the beam azimuth offset. Right now

[0060]

[0061] So we can infer:

[0062]

[0063] S5, calculate the beam azimuth correction value corresponding to the arbitrary beam pointing. Specifically, according to S3, the beam off-axis angle θ corresponding to the arbitrary antenna surface angle δ can be obtained: ′ , according to the beam azimuth offset corresponding to S4 at this time The corrected beam azimuth is

[0064]

[0065] S6, calculate the beam off-axis angle correction value corresponding to the arbitrary beam pointing. Specifically, according to S4, the off-axis angle of the vector A' in the coordinate system Ox'y'z' is the actual off-axis angle of the beam, that is, the corrected beam off-axis angle is:

[0066]

[0067] According to the correction formulas of step S5 and step S6, the corrected beam pointing data is obtained as shown in Table 2:

[0068] Table 2

[0069]

[0070] The beam pointing test data before and after correction are used in the actual sway table satellite alignment test. By comparing the test results, it is found that the corrected data greatly improves the accuracy of the antenna satellite alignment. The test results verify the correctness and practicality of the error calibration method proposed in the present invention.

[0071] The units involved in the embodiments of the present invention may be implemented by software or hardware, and the units described may also be arranged in a processor. The names of these units do not, in some cases, limit the units themselves.

[0072] According to one aspect of an embodiment of the present invention, a computer program product or a computer program is provided, the computer program product or the computer program includes a computer instruction, and the computer instruction is stored in a computer-readable storage medium. A processor of a computer device reads the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the method provided in the above various optional implementations.

[0073] As another aspect, an embodiment of the present invention further provides a computer-readable medium, which may be included in the electronic device described in the above embodiment; or may exist independently without being assembled into the electronic device. The above computer-readable medium carries one or more programs, and when the above one or more programs are executed by an electronic device, the electronic device implements the method described in the above embodiment.

Claims

1. A VICTS antenna beam pointing test error calibration method, characterized in that: The following steps are involved: S1, install the VICTS antenna in the compact field and perform beam pointing test; S2, testing the beam pointing direction on the symmetrical side of the antenna body azimuth plane when a certain antenna surface angle is tested; S3, calculate the angle of the antenna surface normal line deviating from the direction of the compact field plane wave when the compact field turntable is in zero position; S4, calculate the angle value of the antenna surface deviating from the vertical direction; S5, calculating the beam azimuth correction value corresponding to the arbitrary beam pointing; S6, calculating the beam off-axis angle correction value corresponding to the arbitrary beam pointing.

2. The VICTS antenna beam pointing test error calibration method according to claim 1, characterized in that: In step S1, the VICTS antenna is installed in a compact field and a beam pointing test is performed, which specifically includes the following sub-steps: S11, install the VICTS antenna: install the antenna base on the side of the bracket, fix the bottom of the bracket on the azimuth turntable in the compact field, and align the normal of the antenna surface with the direction of the plane wave of the compact field; the angle of the normal of the antenna surface deviating from the direction of the plane wave of the compact field when the turntable of the compact field is zero due to installation error is α, and the angle of the antenna surface deviating from the vertical direction is β; S12, test beam pointing: beam azimuth Data relationship with the antenna surface angle δ The data relationship between the beam off-axis angle θ and the antenna surface angle δ is θ=g(δ), where the antenna surface angle δ represents the angle of rotation of the antenna radiation layer relative to the feed layer, and counterclockwise is positive; For a specified antenna plane angle δ, the antenna beam is pointed in the horizontal plane by rotating the entire antenna body, and the antenna beam is aligned with the direction of the plane wave of the compact field by rotating the compact field azimuth turntable. At this time, the rotation angle of the antenna body is the beam azimuth. The rotation angle of the turntable is the beam off-axis angle θ; and by fine-tuning The antenna gain maximum point is found by using θ and θ to determine the best beam azimuth and off-axis angle test accuracy.

3. The VICTS antenna beam pointing test error calibration method according to claim 1, characterized in that: In step S2, the beam pointing of the symmetrical side of the antenna body azimuth plane when testing a certain antenna surface angle specifically includes the following sub-steps: for a certain antenna surface angle δ0, according to the test result of S1, its beam azimuth angle is The off-axis angle is θ0 = g(δ0); then rotate the antenna body 180 degrees and find the antenna body rotation angle corresponding to the maximum gain through fine-tuning And the rotation angle of the compact turntable 4. The VICTS antenna beam pointing test error calibration method according to claim 3, characterized in that: In step S3, the calculation of the angle of the antenna surface normal line deviating from the direction of the compact field plane wave when the compact field turntable is in zero position specifically includes the following sub-steps: according to the test result of step S2, the off-axis angle correction value is obtained: The off-axis angle correction value is used for the beam pointing corresponding to any positive angle of the antenna surface, and the off-axis angle θ′=θ-α after the first correction is obtained.

5. The VICTS antenna beam pointing test error calibration method according to claim 4, characterized in that: In step S4, the calculating of the angle value of the antenna plane deviating from the vertical direction specifically includes the following sub-steps: According to the test results of S2, when the antenna surface angle is δ0, the beam azimuth deviation caused by the installation error Define the antenna coordinate system as Oxyz, the normal direction of the antenna surface is the y-axis, the vertical direction is the z-axis, and the x-axis is determined by the right-hand rule; define the antenna coordinate system rotated by the error angle β as Ox′y′z′, and the rotation matrix corresponding to the angle β is R x (β); From S3, the angle δ0 corresponds to the corrected off-axis angle θ′0, and the coordinate of this direction in the coordinate system Oxyz is A, so the representation of A in the coordinate system Ox′y′z′ is A′=R x (β)A; here: Among them, sβ represents sin(β), cβ represents cos(β), and so on; At this time, the angle between the projection of A′ on the Ox′z′ plane and Ox′ is the beam azimuth offset. Right now: Thus, we can infer 6. The VICTS antenna beam pointing test error calibration method according to claim 5, characterized in that: In step S5, the calculation of the beam azimuth correction value corresponding to the arbitrary beam pointing specifically includes the following sub-steps: According to step S3, the beam off-axis angle θ′ corresponding to any antenna surface angle δ is obtained, and according to step S4, the corresponding beam azimuth offset at this time is obtained. Then the corrected beam azimuth is:

7. The VICTS antenna beam pointing test error calibration method according to claim 6, characterized in that: In step S6, the calculation of the beam off-axis angle correction value corresponding to the arbitrary beam pointing specifically includes the following sub-steps: According to step S4, the off-axis angle of the vector A′ in the coordinate system Ox′y′z′ is the actual off-axis angle of the beam, that is, the corrected off-axis angle of the beam is:

8. A VICTS antenna beam pointing test error calibration device, characterized in that: The method comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is loaded by the processor, the method according to any one of claims 1 to 7 is executed.

Images