Antenna Testing Method and Testing Control System Based on Robot Arm

Abstract

The present invention belongs to the field of antenna and microwave technology, and discloses an antenna testing method and a testing control system based on a robotic arm for testing the performance of an antenna. The method of the present invention includes: presetting a scanning range and a scanning plane, and roughly scanning to determine the scanning center position; according to the amplitude and phase values recorded in the previous step, comparing with the preset scanning range conditions to estimate the scanning range; scanning one week along the boundary of the estimated scanning range, if the amplitude and phase read during this one-week scanning meet the preset scanning range conditions, a closed area is obtained; generating a rectangular scanning range that can cover the closed area as the formal scanning range; automatically generating a meandering scanning path according to the rectangular scanning range; scanning along the pre-determined meandering scanning path. By using the present invention, the position error accumulated in the antenna testing based on the robotic arm can be controlled within a certain range.

Description

Technical Field

[0001] The invention belongs to the field of antenna and microwave technology, and in particular relates to an antenna testing method and a testing control system based on a mechanical arm. Background Art

[0002] In recent years, with the rapid development of antenna technology and solid-state microwave devices, wireless communication and radar systems have gradually become a reality in the direction of millimeter wave frequency bands and miniaturization, and have been applied in fields such as airport security and high-precision imaging. Antennas, as devices for transmitting and receiving electromagnetic waves, are key components in wireless communication and radar systems, and their performance plays a decisive role in the performance of the entire wireless system. Therefore, the evaluation of antenna performance, especially the evaluation of radiation characteristics represented by directional pattern testing, has become an urgent research topic. In recent years, due to the high frequency and short far-field range of millimeter waves, higher accuracy requirements have been put forward for near-field test systems. Therefore, some researchers have begun to explore the use of millimeter wave antenna test systems based on multi-axis manipulators to meet the accuracy requirements of the test. At the same time, the test platform of the multi-axis robotic arm can conveniently switch between hemispherical, cylindrical, and plane scanning according to the characteristics of the test object; it can also perform far-field or near-field scanning within the motion range of the robotic arm according to the needs of the test; and even because of its small size and easy mobility, it can test some systems under test that are difficult to place in a microwave darkroom. It takes into account both test accuracy and flexibility, has multiple application prospects, and has received widespread attention from researchers.

[0003] However, some shortcomings of the multi-axis robot itself have limited the application prospects of this technology to a certain extent. For example, although the multi-axis robot has high repeatability and movement accuracy, multiple stepping will accumulate position errors. In addition, the position error generated by the multi-axis robot when the scanning path turns will be larger than that of ordinary stepping. In addition to these defects, the traditional scanning process based on the scanning frame, when directly applied to the robot test system, cannot maximize the advantages of the robot in terms of scanning orientation, stepping, etc. Summary of the invention

[0004] The purpose of the present invention is to provide an antenna testing method and a testing control system based on a robotic arm in view of the deficiencies in the prior art, aiming to control the accumulated position error within a certain range, while giving full play to the advantages of the robotic arm testing system that is flexible and can be adaptively adjusted according to the test task as much as possible.

[0005] Specifically, the present invention is implemented by adopting the following technical solutions.

[0006] In one aspect, the present invention provides an antenna testing method based on a robotic arm, comprising:

[0007] Preset the scanning range and scanning plane, and roughly scan to determine the scanning center position: Within the scanning range of the preset scanning plane, start scanning from the initial position and record the amplitude and phase values; If the position of the phase center can be determined based on the amplitude and phase values and the preset phase center judgment criteria, move the robotic arm to this position; If it cannot be determined, expand the scanning range; Until the new phase center position meets the preset phase center judgment criteria;

[0008] Adjust the scanning range and generate a spiral scanning path: Based on the amplitude and phase values recorded in the previous step, estimate the scanning range by comparing with the preset scanning range conditions; Scan around the boundary of the estimated scanning range. If the amplitude and phase read during this one-week scan meet the preset scanning range conditions, expand the scanning area outward and scan around the boundary of the new scanning area until the read amplitude and phase are lower than the preset scanning range conditions, obtaining a closed area; Generate a rectangular scanning range that can cover the closed area as the formal scanning range; Automatically generate a spiral scanning path according to the rectangular scanning range;

[0009] Scan along the pre-determined spiral scanning path.

[0010] Furthermore, the presetting the scanning range and scanning plane, and roughly scanning to determine the scanning center position includes:

[0011] (1) Preset the scanning range and scanning plane; (2) Within the scanning range of the preset scanning plane, start a one-dimensional scan along the first axis direction from the initial position and record the readings of the amplitude and phase; (3) If the scan is sufficient to determine the position of the phase center in the first axis direction according to the preset phase center judgment criteria, move the robotic arm to this position; If it cannot be determined, expand the scanning range in this axis direction; (4) Starting from the position of the phase center in the first axis direction, repeat steps (2) - (3) along the second axis direction to obtain the position of the phase center that meets the preset phase center judgment criteria as the initial phase center position; (5) If the distance between the initial position of the robotic arm and the initial phase center position is less than the preset distance, use the initial phase center position as the phase center position, otherwise use the initial phase center position as the new initial position and repeat steps (2) - (4) to find a new phase center position.

[0012] Furthermore, the antenna testing method based on the robotic arm further includes:

[0013] In the step of adjusting the scanning range and generating a spiral scanning path, it further includes generating a calibration line;

[0014] Before scanning along the pre-determined spiral scanning path, perform a pre-scan along the calibration line and record the corresponding amplitude and phase values;

[0015] In the step of scanning along the pre-determined meandering scan path, when passing through the calibration line, the read amplitude and phase values are compared with the corresponding data read during pre-scanning. When the error exceeds the set range, the probe orientation is adjusted within the scan range, and according to the preset requirements, a point with a smaller error and a smaller adjustment distance is selected to continue the scan.

[0016] Further, the calibration line is a straight line formed by connecting the phase center position and the corner position in the meandering scan path.

[0017] Further, the calibration line is a straight line extending outward from the phase center position along a certain axis.

[0018] Further, the robotic arm-based antenna testing method further includes:

[0019] During the scanning process, according to the amplitude and phase values obtained from the previous several scanning points, the length of the scanning step is adjusted within a preset range.

[0020] Further, the adjusting the length of the scanning step within a preset range includes: if the current scanning point is located in an interval where the corresponding numerical curves of the amplitude and phase obtained from the previous several scanning points change relatively smoothly, or in an interval where the amplitude is lower than a certain threshold, the length of the scanning step is increased.

[0021] Further, the robotic arm-based antenna testing method further includes:

[0022] Before each step movement, predict the possibility of the multi-axis robotic arm getting into a singularity. If there is a risk of getting into a singularity, adjust the scanning method to avoid the robotic arm getting into a singularity.

[0023] Further, the adjusting the scanning method includes adjusting the posture of the robotic arm, or locally modifying the scanning step and the moving path.

[0024] On the other hand, the present invention also provides a robotic arm-based antenna testing control system, including a multi-axis robotic arm, a test probe, a test control module, and a vector network analyzer;

[0025] The antenna under test and the test probe are respectively connected to two RF signal channels of the vector network analyzer;

[0026] The vector network analyzer is connected to the test control module and provides the acquired amplitude and phase data to the test control module in real time;

[0027] The test control module controls the multi-axis robotic arm to perform scanning according to the above-mentioned robotic arm-based antenna test method based on the amplitude and phase information from the vector network analyzer and the position information and robotic arm joint state information provided by the servo system of the multi-axis robotic arm.

[0028] The beneficial effects of the robotic arm-based antenna test method and test control system of the present invention are as follows:

[0029] Through two steps of rough scanning before scanning and scanning range adjustment, the scanning center and scanning range are approximately determined, thereby effectively controlling the truncation error of scanning within the required range of the test, while avoiding unnecessary scanning areas and saving scanning time;

[0030] Adopting a circular scanning path reduces the accumulation of position errors in the scanning center area caused by multiple turns of the scanning path. The accumulation of position errors in the peripheral scanning area can be corrected through pre-scanning;

[0031] Before scanning the readings, a pre-scanning process is carried out. When the scanning test readings pass through this point again after the pre-scanning ends, the probe position is adjusted within a certain range so that the error between the readings and the pre-scanning is within a certain range. This is because the path of the pre-scanning is simple, with fewer turns and steps. By comparing and correcting with the pre-scanning results during the test process, the continuously accumulating position errors during the scanning process can be corrected to an acceptable range;

[0032] During the test process, according to the scanning readings and test requirements, the step distance is adaptively adjusted, thereby shortening the scanning time and reducing the accumulation of step errors;

[0033] The test system predicts the possibility of the multi-axis robotic arm falling into a singularity according to the data of the robotic arm servo, and avoids the multi-axis robotic arm from falling into a singularity by pre-adjusting the robotic arm posture or locally adjusting the scanning step and scanning path.

[0034] The robotic arm-based antenna test method and test control system of the present invention, based on the motion characteristics of the multi-axis robotic arm and combined with the test requirements, realize the automation and intelligence of the test process from multiple steps, such as automatically adjusting the scanning range, automatically avoiding singularities, and adaptively adjusting the steps, etc., which can greatly improve the efficiency of antenna testing. At the same time, the position errors accumulated during the motion of the robotic arm are effectively controlled, and the efficiency and performance of the test are improved without increasing the additional test hardware cost, which has important application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the hardware system for near-field testing of a robotic arm antenna of the present invention.

[0036] Figure 2is applicable to the present invention Figure 1 Hardware control system block diagram.

[0037] Figure 3 is the overall flowchart of the antenna near-field test method according to an embodiment of the present invention.

[0038] Figure 4 is the overall flowchart of the antenna near-field test method according to another embodiment of the present invention.

[0039] Figure 5 is the flowchart for roughly scanning and approximately determining the scanning center position provided by the present invention.

[0040] Figure 6 is the flowchart for adjusting the scanning range and generating a loop scanning path provided by the present invention.

[0041] Figure 7 is a calibration line pre-scanning path and a loop scanning path provided by the present invention.

[0042] Figure 8 is a pre-scanning flowchart provided by the present invention.

[0043] Reference numerals in the figure: 1 - multi-axis robotic arm, 2 - test probe, 3 - antenna under test, 4 - support platform for the antenna under test, 5 - antenna erection platform, 6 - test cabinet, 7 - display system, 8 - vector network analyzer, 9 - test control module, 10 - near-field scanning range, 11 - near-field scanning path, 12 - near-field scanning calibration line. Detailed implementation manners

[0044] The present invention will be further described in detail below in conjunction with embodiments and with reference to the accompanying drawings. The robotic arm-based antenna test control system adopted by the present invention can be applied to the near-field test of antennas. When the scanning range of the multi-axis robotic arm meets the far-field conditions of the antenna, this test system can also be used for far-field antenna pattern measurement of the antenna.

[0045] Embodiment 1:

[0046] In an embodiment of the present invention, taking the near-field test of an antenna by a robotic arm as an example, a robotic arm-based antenna test method and test control system are introduced.

[0047] As Figure 1 shown, the robotic arm-based antenna test control system adopted in this embodiment mainly includes a multi-axis robotic arm 1, a test probe 2, a test control module 9, and a vector network analyzer 8. The test probe 2 is fixed to the wrist of the multi-axis robotic arm 1, and the antenna under test 3 is fixed to the antenna erection platform 5 through the support platform 4 for the antenna under test. The display system 7 is used to display information such as the scanning path. The display system 7, the vector network analyzer 8, and the test control module are arranged in the test cabinet 6.

[0048] The test control module 9 reads the amplitude and phase information from the vector network analyzer 8, and the position information and the robotic arm joint state information provided by the robotic arm servo system, and controls the robotic arm to perform scanning according to the robotic arm-based antenna test method of the present invention. The position information here comes from the calculation of the robotic arm servo system rather than actual measurement. The antenna test control module 9 adopted in this embodiment has three basic functions: scanning path adjustment, scanning step adjustment, and robotic arm attitude adjustment, which are used to continuously set or correct the scanning task during the whole working process and synchronize it to the multi-axis robotic arm, so as to complete the steps in the robotic arm-based antenna test method.

[0049] As Figure 2 shown, the antenna under test 3 and the test probe 2 are respectively connected to two RF signal channels of the vector network analyzer 8. The vector network analyzer 8 is connected to the test control module 9 and provides the acquired test data (amplitude and phase) to the test control module 9 in real time. The test control module 9 analyzes and adjusts the scanning path, step, or performs necessary attitude adjustment according to the pre-designed scanning trajectory, the amplitude-phase data provided by the network analyzer 8, the internal position readings and joint states provided by the servo system of the multi-axis robotic arm 1.

[0050] As Figure 3 shown, based on the above platform, in one embodiment, the process of the robotic arm-based antenna test method of the present invention includes:

[0051] I. Preset the scanning range and scanning plane, and roughly scan to determine the scanning center position;

[0052] II. Adjust the scanning range to generate a circular scanning path;

[0053] III. Scan along the pre-determined circular scanning path.

[0054] As Figure 4 shown, in another embodiment, the process of the robotic arm-based antenna test method of the present invention includes:

[0055] I. Preset the scanning range and scanning plane, and roughly scan to determine the scanning center position;

[0056] II. Adjust the scanning range to generate a circular scanning path and a calibration line;

[0057] III. Pre-scan along the calibration line direction and record data;

[0058] IV. Scan along the pre-determined circular scanning path.

[0059] The specific process of each step will be introduced in detail through specific examples below.

[0060] 1. Preset the scanning range and scanning plane, and roughly scan to determine the position of the scanning center.

[0061] Within the scanning range of the preset scanning plane, start scanning from the initial position and record the amplitude and phase values; if the position of the phase center can be determined based on the amplitude and phase values and the preset phase center judgment criterion, move the robotic arm to this position; if not, expand the scanning range; until the new phase center position meets the preset phase center judgment criterion.

[0062] Preferably, in one embodiment, as Figure 5 shown, determine the position of the scanning center according to the following steps.

[0063] (1) Preset the scanning range and scanning plane (such as a plane, cylinder surface or hemispherical surface) according to engineering experience. Figure 5 Taking the plane as an example, assume the initial position of the robotic arm is (x0, y0).

[0064] (2) Within the preset scanning range, start a one-dimensional scan along the first axis direction from the initial position and record the readings of the amplitude and phase. For example, perform a one-dimensional scan along the direction parallel to the x-axis (y = y0).

[0065] (3) If the scan is sufficient to determine the position (x1, y0) of the phase center in the first axis direction according to the preset phase center judgment criterion, move the robotic arm to this position (x1, y0); if not, expand the scanning range in the direction of this axis (x-axis).

[0066] The preset phase center judgment criterion can be set by comparing the amplitude and phase readings obtained from the current scan with the phase center. For example, it is set that within a certain range near the highest amplitude value among all the scanned points in the scanning range, the position where the phase extreme value is located is the phase center. The judgment criterion of the phase center can be inferred according to the distribution law of the amplitude and phase. Since the purpose of the present invention is not to find the phase center of the antenna to be measured, it only needs to roughly determine the position to facilitate the next step of determining the scanning range, without precise determination, thus saving the test time. The phase center judgment criterion can be determined in combination with the test time, the required test accuracy, etc.

[0067] (4) Starting from the position of the phase center in the first axis direction, repeat steps (2) - (3) along the second axis (such as the y-axis) direction to obtain the phase center position (x1, y1) that meets the preset phase center judgment criterion as the initial phase center position.

[0068] (5) If the distance between the initial position (x0, y0) of the robotic arm and the initial phase center position (x1, y1) is less than the preset distance L, then use the initial phase center position (x1, y1) as the phase center; otherwise, use the initial phase center position as the new initial position, that is, replace the values of (x0, y0) with (x1, y1), and repeat steps (2) to (4) to find the new phase center position. Note that since we do not need to accurately determine the center point of the scan, the value of L should not be too small, and it is appropriate to repeat 1 - 2 times to save test time. The preset distance L can be determined by combining the test time, the required test accuracy, etc.

[0069] By performing a certain rough adjustment scanning process before the start of the scan, the scan center can be roughly found or the scan range can be determined, so as to ensure that the truncation error of the scan is within a controllable range and avoid unnecessary scan areas.

[0070] II. Adjust the scan range to generate a spiral scan path.

[0071] As Figure 6 shown, the detailed steps are as follows:

[0072] (1) According to the amplitude and phase values recorded in Step 1, by comparing with the preset scan range conditions, estimate the scan range to obtain the estimated scan range. The preset scan range conditions here are determined by the read amplitude and phase, as well as the requirements of the test for the truncation error. For example, it can be set that when the amplitude measured by the probe is lower than a certain value relative to the amplitude at the highest point during the scan process, this point can be determined to be outside the estimated scan range.

[0073] (2) Scan along the boundary of the estimated scan range for one week. If the amplitude and phase read during this one - week scan meet the preset scan range conditions (that is, not lower than the lowest value within the preset scan range), it is considered that this area is within the preset scan range, then expand the scan area outward and scan along the boundary of the new scan area for one week until the read amplitude and phase are lower than the preset scan range conditions, obtaining a closed area;

[0074] (3) According to the closed area drawn in step (2), generate a rectangular scan range that can cover this closed area as the formal scan range;

[0075] (4) Automatically generate a spiral scan path according to this rectangular scan range.

[0076] The purpose of using a spiral path is that in the central area with a relatively high power density, the position error is at a relatively low level due to fewer step numbers and corner numbers, while the outer area relies on the calibration process, so as to ensure that the amplitude - phase error caused by the position error in the entire scan area is within a controllable range.

[0077] Further, in another embodiment, when generating a meandering scan path, a calibration line is also generated. The calibration line is used to adjust the probe position according to the acquired amplitude-phase values when the multi-axis robotic arm scans along the pre-determined meandering scan path, so that the reading error is within a certain range compared with the amplitude-phase values acquired during the pre-scan along the calibration line, in order to control the position error accumulated during the scan along the pre-determined meandering scan path. Since the pre-scan path is simple, with fewer turns and steps, during the test, by comparing and correcting with the pre-scan results, the continuously accumulating position error during the scan can be corrected to an acceptable range.

[0078] Referring Figure 7 , Figure 7 FIG. provides an example of the scanning range 10, the meandering scan path 11, and the position of the calibration line 12. In this example, a meandering scan path is adopted, and the calibration line 12 is selected as the straight line formed by connecting the phase center position and the corner position 11 in the meandering scan path. It can be understood that the calibration line can also be a straight line extending outward from the phase center position along a certain axis (X-axis or Y-axis) or other routes.

[0079] III. (Optional) Pre-scan along the calibration line direction and record data.

[0080] When using the calibration line to control the accumulated position error, before scanning along the pre-determined meandering scan path, perform a pre-scan process along the calibration line and record the corresponding amplitude and phase values.

[0081] As Figure 8 shown, scan along the calibration line set in step II respectively and record the corresponding amplitude-phase readings as the basis for position calibration in step IV.

[0082] IV. Scan along the pre-determined (step II) meandering scan path.

[0083] By adopting a meandering scan path, the accumulation of position errors caused by multiple turns of the scan path in the key scanning area can be reduced.

[0084] Further, in another embodiment, in the step of scanning along the pre-determined meandering scan path, when passing through the calibration line, compare the read amplitude and phase values with the corresponding data read during the pre-scan. When the error exceeds the set range, adjust the probe orientation within the scanning range, and according to the preset requirements, select a point with a smaller error and a smaller adjustment distance to continue scanning.

[0085] Further, in another embodiment, during the scanning process, the length of the scanning step is adjusted within a certain range according to the amplitude and phase values obtained from the previous several points. For example, if the current scanning point is located in an interval where the numerical curves of the amplitude and phase obtained from the previous several scanning points change relatively smoothly, or in an interval where the amplitude is lower than a certain threshold, the length of the scanning step is increased, so as to achieve the purpose of reducing the scanning time and at the same time reducing the accumulation of step errors.

[0086] Further, in another embodiment during the scanning process, before each step movement, the robotic arm servo system pre-sends the joint states and the joint movements to be executed to the test control module in advance. The test control module can predict in advance the possibility of the multi-axis robotic arm getting into a singularity. If there is a risk of getting into a singularity, the scanning method can be adjusted according to a certain scanning strategy to avoid the robotic arm getting into a singularity. For example: adjusting the posture of the robotic arm so that it re-enters the original scanning position in another posture; or locally modifying the scanning step and the moving path to avoid the singularity while meeting the sampling requirements.

[0087] The antenna test method and test control system based on a robotic arm according to the present invention, based on the motion characteristics of a multi-axis robotic arm and combined with test requirements, realizes the automation and intelligence of the test process from multiple steps. For example, automatically adjusting the scanning range, automatically avoiding singularities, and adaptively adjusting the steps, etc., can greatly improve the efficiency of antenna testing. At the same time, the position errors accumulated during the movement of the robotic arm are effectively controlled. Without increasing the additional test hardware cost, the efficiency and performance of the test are improved, which has important application value.

[0088] In some embodiments, certain aspects of the above technologies can be implemented by one or more processors of a processing system that executes software. The software includes one or more sets of executable instructions stored or otherwise tangibly implemented on a non-transitory computer-readable storage medium. The software may include instructions and certain data, which, when executed by one or more processors, manipulate the one or more processors to execute one or more aspects of the above technologies. The non-transitory computer-readable storage medium may include, for example, magnetic or optical storage devices, solid-state storage devices such as flash memory, cache, random access memory (RAM), or other non-volatile memory devices. The executable instructions stored on the non-temporary computer-readable storage medium may be source code, assembly language code, object code, or other instruction formats interpreted or otherwise executed by one or more processors.

[0089] A computer-readable storage medium may include any storage medium or combination of storage media that can be accessed by a computer system during use to provide instructions and / or data to the computer system. Such storage media may include, but are not limited to, optical media (e.g., compact discs (CDs), digital versatile discs (DVDs), Blu-ray discs), magnetic media (e.g., floppy disks, magnetic tapes, or magnetic hard disk drives), volatile memory (e.g., random access memory (RAM) or cache), non-volatile memory (e.g., read-only memory (ROM) or flash memory), or microelectromechanical systems (MEMS)-based storage media. The computer-readable storage medium may be embedded in the computing system (e.g., system RAM or ROM), fixedly attached to the computing system (e.g., magnetic hard disk drive), removably attached to the computing system (e.g., optical disc or universal serial bus (USB)-based flash memory), or coupled to the computer system via a wired or wireless network (e.g., network-attached storage (NAS)).

[0090] Note that not all activities or elements in the above general description are required, that a portion of a particular activity or device may not be required, and that one or more further activities or elements may be performed or included in addition to those described. Further, the order in which the activities are listed need not be the order in which they are performed. Also, these concepts have been described with reference to specific embodiments. However, those of ordinary skill in the art will recognize that various modifications and changes can be made without departing from the scope of the present disclosure as set forth in the following claims. Accordingly, the specification and drawings are to be regarded as illustrative rather than restrictive, and all such modifications are included within the scope of the present disclosure.

[0091] Benefits, other advantages, and solutions to problems have been described above with respect to specific embodiments. However, any benefit, advantage, solution to problems, or any feature that causes any benefit, advantage, or solution to occur or become more apparent should not be construed as a critical, required, or essential feature of any or all claims. Additionally, the specific embodiments disclosed above are merely illustrative, as the disclosed subject matter may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. There is no intention to limit the details of the construction or design shown herein other than as described in the following claims. It is, therefore, evident that the specific embodiments disclosed above may be altered or modified, and all such variations are considered to be within the scope of the disclosed subject matter. Accordingly, the protection sought herein is as set forth in the following claims.

Claims

1. An antenna testing method based on a robotic arm, characterized in that Including: A preset scanning range and scanning plane, and roughly scanning to determine the scanning center position: within the scanning range of the preset scanning plane, start scanning from the initial position, and record the amplitude and phase values; if the position of the phase center can be determined based on the amplitude and phase values and the preset phase center judgment criterion, move the robotic arm to this position; if it cannot be determined, expand the scanning range; until the new phase center position meets the preset phase center judgment criterion; Adjust the scanning range and generate a spiral scanning path: Based on the amplitude and phase values recorded in the previous step, estimate the scanning range by comparing with the preset scanning range conditions; scan around the boundary of the estimated scanning range for one week. If the amplitude and phase read during this one-week scan meet the preset scanning range conditions, expand the scanning area outward, scan around the boundary of the new scanning area for one week until the read amplitude and phase are lower than the preset scanning range conditions, obtaining a closed area; generate a rectangular scanning range that can cover the closed area as the formal scanning range; automatically generate a spiral scanning path according to the rectangular scanning range; Scan along the pre-determined spiral scanning path.

2. The antenna testing method based on a robotic arm according to claim 1, wherein The preset scanning range and scanning plane, and roughly scanning to determine the scanning center position include: (1) A preset scanning range and scanning plane; (2) within the scanning range of the preset scanning plane, start one-dimensional scanning along the first axis direction from the initial position, and record the readings of the amplitude and phase; (3) if the scanning is sufficient to determine the position of the phase center in the first axis direction according to the preset phase center judgment criterion, move the robotic arm to this position; if it cannot be determined, expand the scanning range in the direction of this axis; (4) repeat steps (2) to (3) along the second axis direction starting from the position of the phase center in the first axis direction to obtain the phase center position that meets the preset phase center judgment criterion as the initial phase center position; (5) if the distance between the initial position of the robotic arm and the initial phase center position is less than the preset distance, use the initial phase center position as the phase center position, otherwise use the initial phase center position as the new initial position, and repeat steps (2) to (4) to find a new phase center position.

3. The antenna testing method based on a robotic arm according to claim 1, wherein Also including: In the step of adjusting the scanning range and generating a spiral scanning path, it also includes generating a calibration line; Before scanning along the pre-determined spiral scanning path, perform a pre-scan along the calibration line and record the corresponding amplitude and phase values; In the step of scanning along the pre-determined spiral scanning path, when passing through the calibration line, compare the read amplitude and phase values with the corresponding data read during the pre-scan. When the error exceeds the set range, adjust the probe orientation within the scanning range, and according to the preset requirements, select a point with a smaller error and a smaller adjustment distance to continue scanning.

4. The method for testing an antenna based on a robotic arm according to claim 3, wherein The calibration line is a straight line formed by connecting the phase center position and the corner position in the spiral scanning path.

5. The method for testing an antenna based on a robotic arm according to claim 3, wherein The calibration line is a straight line extending outward along a certain axis from the phase center position.

6. The method for testing an antenna based on a robotic arm according to claim 3, wherein Also including: During the scanning process, adjust the length of the scanning step within a preset range according to the amplitude and phase values obtained from the previous several scanning points.

7. The antenna testing method based on a robotic arm according to claim 6, wherein Adjusting the length of the scanning step within a preset range includes: if the current scanning point is located in an interval where the numerical curves of the amplitude and phase obtained from the previous several scanning points change relatively smoothly, or in an interval where the amplitude is lower than a certain threshold, increase the length of the scanning step.

8. The antenna testing method based on a robotic arm according to claim 1, wherein It also includes: Before each step movement, predict the possibility of the multi-axis robotic arm falling into a singularity. If there is a risk of falling into a singularity, adjust the scanning method to avoid the robotic arm falling into a singularity.

9. The method for testing an antenna based on a robotic arm according to claim 8, wherein The adjustment of the scanning method includes adjusting the posture of the robotic arm, or locally modifying the scanning step and the movement path.

10. An antenna test control system based on a robotic arm, characterized in that, It includes a multi-axis robotic arm, a test probe, a test control module, and a vector network analyzer; The antenna under test and the test probe are respectively connected to two RF signal channels of the vector network analyzer; The vector network analyzer is connected to the test control module and provides the acquired amplitude and phase data to the test control module in real time; The test control module controls the multi-axis robotic arm to perform scanning according to the robotic arm-based antenna test method described in any one of claims 1 to 9 based on the amplitude and phase information from the vector network analyzer and the position information and robotic arm joint state information provided by the servo system of the multi-axis robotic arm.

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