A VICTS antenna beam pointing test error calibration method and device

Abstract

The present invention discloses a VICTS antenna beam pointing test error calibration method and device, belonging to the field of satellite communications, comprising the following steps: installing the VICTS antenna in a compact range and performing a beam pointing test; testing the beam pointing of the symmetrical side of the antenna body azimuth plane at a certain antenna surface angle; calculating the angle at which the antenna surface normal deviates from the plane wave direction of the compact range when the compact range turntable is at zero position; calculating the angle value at which the antenna surface deviates from the vertical direction; calculating the beam azimuth angle correction value corresponding to any beam pointing; and calculating the beam off-axis angle correction value corresponding to any beam pointing. The present invention solves the problem of inaccurate beam pointing tests caused by installation errors when the existing VICTS antenna is tested in a compact range darkroom.

Description

Technical Field

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

[0002] In recent years, VICTS antennas have been increasingly used in satellite communications due to their low profile, high scanning efficiency, high reliability, and low cost. Beam pointing testing is the technical foundation for these antennas' satellite communications. The test data is used to guide the antenna beam's precise alignment with the satellite.

[0003] Currently, VICTS antenna beam pointing is typically tested using planar near-field or spherical near-field testing. However, these two test fields require full-space beam pointing testing of the antenna, resulting in low test efficiency and prone to installation errors and near-field to far-field conversion errors. These multiple error sources make it difficult to obtain accurate beam pointing test results through correction. Compact range testing has been widely used in antenna electrical performance testing due to its simple construction, lack of near-field to far-field conversion requirements, high test efficiency, and low cost. For VICTS antennas, a compact range can be used for targeted beam pointing testing, improving test efficiency and accuracy.

[0004] When conducting beam pointing tests in a compact range, it's necessary to record the antenna body rotation angle and the azimuth turntable rotation angle as beam pointing test results. However, these two angles are significantly affected by antenna installation errors. For beams near the antenna normal, even small installation errors can result in test errors of tens of degrees. Installation errors primarily include the angle at which the antenna plane normal deviates from the compact range azimuth zero, as well as the angle at which the antenna plane deviates from the vertical.

[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 in dynamic conditions, and thus unable to achieve stable communication. Summary of the Invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a VICTS antenna beam pointing test error calibration method and device 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 includes the following steps:

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

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

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

[0012] S4, calculate the angle value of the antenna surface 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] Furthermore, 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 to the azimuth turntable in the compact range, aligning the normal of the antenna surface with the direction of the plane wave from the compact range. The angle α at which the normal of the antenna surface deviates from the direction of the plane wave from the compact range due to installation error when the turntable is at zero position is the same as the angle β at which the antenna surface deviates from the vertical.

[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, which are used to determine the best beam azimuth and off-axis angle test accuracy.

[0019] Furthermore, 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] Furthermore, in step S3, the angle of the antenna surface normal deviating from the direction of the plane wave of the compact range when the compact range turntable is at zero position is calculated, which 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 applied to the beam pointing corresponding to any positive angle of the antenna surface, and the off-axis angle after the first correction is obtained as θ′=θ-α.

[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 offset caused by the installation error is 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); The angle δ0 obtained from S3 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; where:

[0023] but

[0024] Where 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] Furthermore, in step S5, the calculation 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 The corrected beam azimuth is:

[0030]

[0031] Furthermore, 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:

[0032] According to step S4, the off-axis angle of 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 test the VICTS antenna beam pointing, which has high test efficiency.

[0037] (2) Based on the original test data, the present invention only tests one additional pointing state to obtain correction values ​​for all pointing states, with almost no additional darkroom testing cost.

[0038] (3) The present invention greatly improves the beam pointing test accuracy of the VICTS antenna by calibrating the test data, further improving 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 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 invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0040] Figure 1 Flowchart of a beam pointing test error calibration method for a VICTS antenna according to an embodiment of the present invention;

[0041] Figure 2 Schematic diagram of a compact test scenario for a VICTS antenna according to 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 in FIG, a beam pointing test error calibration method for a VICTS antenna is proposed, which includes the following steps:

[0047] S1, install the VICTS antenna in the compact field and conduct beam pointing test. Figure 2 The figure shows a schematic diagram of the compact range test scenario for the VICTS antenna. The VICTS antenna is installed by mounting the antenna base on the side of a bracket (e.g., a wooden frame), with the bottom of the wooden frame fixed on an azimuth turntable within the compact range, so that the normal of the antenna surface is aligned with the direction of the plane wave coming from the compact range. Figure 3 Figure 2 shows the installation error sources of the VICTS antenna when the azimuth turntable is at zero position. The angle α at which the normal to the antenna surface deviates from the direction of the compact field plane wave is, and the angle β at which the antenna surface deviates from the vertical direction is.

[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 feed 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 then rotate the compact field azimuth turntable to align the antenna beam with the direction of 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 in 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 the most accurate.

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

[0052] Table 1

[0053]

[0054] S2, test 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 test method of S1. 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 at 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 to 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, we can get that when the included 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 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 in steps S5 and 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 were used in actual oscillating platform satellite alignment tests. By comparing the test results, it was found that the corrected data greatly improved the accuracy of the antenna satellite alignment. The test results verified the correctness and practicality of the error calibration method proposed in this invention.

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

[0072] According to one aspect of an embodiment of the present invention, a computer program product or computer program is provided, comprising computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the methods provided in the various optional implementations described above.

[0073] As another aspect, embodiments of the present invention further provide a computer-readable medium, which may be included in the electronic device described in the above embodiments, or may exist independently and not incorporated into the electronic device. The computer-readable medium carries one or more programs, and when executed by the electronic device, the electronic device implements the methods described in the above embodiments.

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 conduct beam pointing test; S2, testing the beam pointing direction on the symmetrical side of the antenna body azimuth plane when a certain antenna plane angle is specified; S3, calculate the angle of the antenna surface normal from the direction of the compact field plane wave when the compact field turntable is at zero position; S4, calculate the angle value of the antenna surface 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; 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 range, and align the normal of the antenna surface with the direction of the plane wave of the compact range; the angle of the normal of the antenna surface deviating from the direction of the plane wave of the compact range when the turntable is at zero position due to installation error is , the angle of the antenna surface from the vertical direction is ; S12, test beam pointing: beam azimuth Angle with antenna surface Data relationship , beam off-axis angle Angle with antenna surface Data relationship , where the antenna angle Indicates the angle of rotation of the antenna radiation layer relative to the feeding layer, counterclockwise is positive; For the specified antenna angle By rotating the entire antenna body, the antenna beam is pointed in the horizontal plane, and by rotating the compact field azimuth turntable, the antenna beam is aligned with the direction of 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 ; and by fine-tuning and Find the maximum point of antenna gain to determine the best beam azimuth and off-axis angle test accuracy; 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: , according to the test results of S1, its beam azimuth is , the off-axis angle is ; 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 field turntable ; In step S3, the angle of the antenna surface normal deviating from the direction of the compact field plane wave when the compact field turntable is at zero position is calculated, which specifically includes the following sub-steps: According to the test result of step S2, the following is obtained: , used for beam pointing corresponding to any positive angle of the antenna surface, and obtain the first corrected off-axis angle ; In step S4, the calculation 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 The beam azimuth offset caused by the installation error is ;Define the antenna coordinate system as , the normal direction of the antenna surface is Axis, vertically upward Axis, determined by the right-hand rule Axis; defined by The antenna coordinate system after rotation is , at this time the angle The corresponding rotation matrix is ; From S3, we get the angle The corresponding corrected off-axis angle is , which points to The coordinates in , then In the coordinate system The representation in is ;here: , ,but ; in, express , express , and so on; at this time, exist Projection of the plane and The angle between the beam and the ,Right now: ； Thus, we can infer .

2. The VICTS antenna beam pointing test error calibration method according to claim 1, 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, any antenna surface angle is obtained Corresponding beam off-axis angle , according to the corresponding beam azimuth offset in step S4 , then the corrected beam azimuth is: 。 3. The VICTS antenna beam pointing test error calibration method according to claim 2, 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, vector In the coordinate system The off-axis angle in is the actual off-axis angle of the beam, that is, the corrected off-axis angle of the beam is: 。 4. 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 3 is executed.

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