Antenna regulation and control method capable of compensating distance from measured object along with change of phase center

Abstract

The invention is suitable for the technical field of antenna regulation and control methods, and provides an antenna regulation and control method capable of compensating the distance from a measured object along with the change of a phase center, and the method comprises the following steps: S1, building a coordinate system; s2, establishing a phase center change relational expression; s3, establishing a to-be-selected algorithm library; s4, selecting a starting test point; s5, setting basic parameters of the antenna; s6, inquiring whether compensation is carried out or not; s7, selecting an algorithm for testing; s8, starting testing; s9, calculating an actual offset; s10, adjusting and controlling the position of the antenna in real time; s11, ending the test and analyzing the result; s12, regularly maintaining the test equipment; according to the method, before an electromagnetic compatibility test, the change relation of the antenna phase center along with the working frequency is calculated, a to-be-selected algorithm library is established, the distance between the antenna phase center and a tested object is regulated and controlled in real time by applying a compensation algorithm in the test process, and the distance between the antenna phase center and the tested object is kept basically unchanged; therefore, the uncertainty caused by the change of the phase center of the antenna and the allowance of the measurement distance as the influence quantity is reduced.

Description

Technical Field

[0001] This invention belongs to the technical field of antenna control methods, and particularly relates to an antenna control method in which the distance from the object being measured can be compensated for as the phase center changes. Background Technology

[0002] In existing technologies, antennas used for electromagnetic compatibility testing employ fixed-position detection, making it impossible to adjust the distance between the antenna phase center and the object under test (DUT) in the antenna's pointing direction in real time. During actual operation, the actual phase center of the antenna shifts with changes in the operating frequency, resulting in uncertainties in the fixed-position detection results due to variations in the antenna phase center and the tolerance of the measurement distance.

[0003] The mainstream solution in existing testing methods is to accommodate the fact that uncertainty objectively exists, leading to lower measurement accuracy, and to include this uncertainty in the test results. Taking the 3-meter method test model as an example, under the conditions of a 3-meter distance and a frequency of 200MHz-1GHz, the change in the phase center will contribute 0.58dB of measurement uncertainty. That is, for a signal with an actual electric field strength of 10V / m, there may be a measurement error of about 0.7V / m. Summary of the Invention

[0004] This invention provides an antenna control method that compensates for changes in the distance to the object under test as the phase center changes. It aims to solve the problem in the prior art that the distance between the antenna phase center and the object under test in the antenna pointing direction cannot be controlled in real time, and the test results have uncertainties caused by changes in the antenna phase center and the allowable tolerance of the measurement distance.

[0005] This invention is implemented as follows: an antenna control method that compensates for changes in distance from the object being measured as the phase center changes, comprising the following steps:

[0006] S1. Establish a coordinate system: Establish a three-dimensional rectangular coordinate system with the original phase center of the antenna as the origin O;

[0007] S2. Establish the phase center change relationship, with two methods to choose from:

[0008] S2-1. Based on existing physical principles and antenna characteristics, establish a theoretical model to predict the relationship between the antenna phase center and the operating frequency, and analytically derive the relevant formula. ;

[0009] S2-2. At different operating frequencies, collect data on the actual phase center position of the antenna. Based on mathematical statistics, fit and generate a regression relationship between the antenna phase center and the operating frequency. ;

[0010] in, This is the actual operating frequency. It is the offset of the actual working phase center relative to the original position;

[0011] S3. Establish a library of candidate algorithms;

[0012] S4. Select the starting test point: Set the origin O, i.e., the original phase center of the antenna, to the starting test point. Record the initial distance between the origin O and the object under test as . ;

[0013] S5. Set antenna polarization, height, frequency range and other parameters to prepare for testing;

[0014] S6. Inquire whether to perform compensation adjustment for phase center offset; if yes, proceed to step S7; if no, proceed to step S8.

[0015] S7. Select a test algorithm: Based on actual testing needs, select a suitable test algorithm from the algorithm library established by calculation;

[0016] S8. Start testing; if option S6 is yes, proceed to step S9; if option S6 is no, proceed to step S11.

[0017] S9. Calculate the actual offset: based on the actual operating frequency. The selected test The algorithm calculates the offset of the phase center relative to the original position in real time.

[0018] Based on the initial distance At this time, the actual phase center is at a distance from the object being measured. for:

[0019] ;

[0020] S10. Real-time antenna position adjustment: The moving antenna compensates for phase center offset and maintains the actual working distance. equal to the initial distance The movement method is:

[0021]

[0022] That is, the antenna is moved in real time in the opposite direction of the phase center offset, and the moving distance is the absolute value of the phase center offset, until the test ends;

[0023] S11. Test Completion and Result Analysis: After the test is completed, the test results are recorded and analyzed.

[0024] S12. Regular maintenance of test equipment: Develop a maintenance plan based on the operating frequency and duration of the antenna test system, and perform regular maintenance and calibration.

[0025] Preferably, in S1, the positive direction of the X-axis is defined as the opposite direction of the antenna pointing direction, and the Y-axis and Z-axis are perpendicular to the Z-axis, thus establishing a rectangular coordinate system.

[0026] Preferably, in S2-1, the theoretical derivation algorithm includes two types: "calculating and establishing the relationship between the distance of the maximum radiating oscillator from the origin and the working frequency, while keeping the distance between the maximum radiating oscillator and the object under test basically unchanged" and "approximately calculating the relationship between the phase center and the working frequency using the similarity principle, while keeping the distance between the phase center and the object under test basically unchanged".

[0027] Preferably, in step S2-2, the regression analysis algorithm includes the steps of "scatter plot establishment", "regression relationship establishment", "significance test" and "regression equation selection";

[0028] Preferably, in S3, the candidate algorithm library for the phase center change relationship should include at least one of the S2-1 and S2-2 algorithms.

[0029] Preferably, in step S10, the measurement is performed using either a laser tracker or a high-precision radar.

[0030] Preferably, in step S11, the relevant data includes field strength, the state information of the object under test, operating frequency, phase center offset, and antenna movement distance.

[0031] Preferably, in step S12, periodic calibration and debugging are performed, including checking the operating status of mechanical devices and calibrating measuring equipment, to ensure the accuracy and stability of system test results.

[0032] Beneficial effects

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows: The antenna control method of the present invention, which compensates for the change in phase center of the distance from the object under test, obtains a library of candidate algorithms for the relationship between the phase center of the antenna and the operating frequency by performing theoretical calculations, theoretical approximate calculations, mathematical statistics, and regression analysis on the relationship between the phase center offset and the operating frequency before using the antenna for electromagnetic compatibility testing. After selecting the initial test point and setting the basic antenna parameters, the tester can choose whether to apply compensation control for the change in phase center. The test process of compensation control calculates the offset of the actual working phase center of the antenna relative to the original position in real time according to the selected change relationship algorithm. The antenna compensation distance is adjusted in real time according to the calculation results to keep the distance between the antenna phase center and the object under test basically unchanged, thereby reducing the uncertainty caused by the change in antenna phase center and the allowable error of measurement distance, and improving the test accuracy. Attached Figure Description

[0034] Figure 1This is a flowchart of the antenna control method of the present invention, which compensates for the change in distance from the object to be measured as the phase center changes;

[0035] Figure 2 This is a schematic diagram of the antenna parameters derived theoretically from the phase center change relationship in this invention.

[0036] Figure 3 This is a schematic diagram of the data acquisition location for the regression analysis of the phase center change relationship in this invention. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0038] Please see Figure 1 , 2 and Figure 3 This invention provides a technical solution: an antenna control method that compensates for changes in distance from the object being measured as the phase center changes, comprising the following steps:

[0039] S1. Establish a coordinate system: Establish a three-dimensional rectangular coordinate system with the original phase center of the antenna as the origin O;

[0040] S2. Establish the phase center change relationship, with two methods to choose from:

[0041] S2-1. Based on existing physical principles and antenna characteristics, establish a theoretical model to predict the relationship between the antenna phase center and the operating frequency, and analytically derive the relevant formula. ;

[0042] S2-2. At different operating frequencies, collect data on the actual phase center position of the antenna. Based on mathematical statistics, fit and generate a regression relationship between the antenna phase center and the operating frequency. ;

[0043] in, This is the actual operating frequency. It is the offset of the actual working phase center relative to the original position;

[0044] S3. Establish a library of candidate algorithms;

[0045] S4. Select the starting test point: Set the origin O, i.e., the original phase center of the antenna, to the starting test point. Record the initial distance between the origin O and the object under test as . ;

[0046] S5. Set antenna polarization, height, frequency range and other parameters to prepare for testing;

[0047] S6. Inquire whether to perform compensation adjustment for phase center offset; if yes, proceed to step S7; if no, proceed to step S8.

[0048] S7. Select a test algorithm: Based on actual testing needs, select a suitable test algorithm from the algorithm library established by calculation;

[0049] S8. Start testing; if option S6 is yes, proceed to step S9; if option S6 is no, proceed to step S11.

[0050] S9. Calculate the actual offset: based on the actual operating frequency. The selected test The algorithm calculates the offset of the phase center relative to the original position in real time.

[0051] Based on the initial distance At this time, the actual phase center is at a distance from the object being measured. for:

[0052] ;

[0053] S10. Real-time antenna position adjustment: The moving antenna compensates for phase center offset and maintains the actual working distance. equal to the initial distance The movement method is:

[0054]

[0055] That is, the antenna is moved in real time in the opposite direction of the phase center offset, and the moving distance is the absolute value of the phase center offset, until the test ends;

[0056] S11. Test Completion and Result Analysis: After the test is completed, the test results are recorded and analyzed.

[0057] S12. Regular maintenance of test equipment: Develop a maintenance plan based on the operating frequency and duration of the antenna test system, and perform regular maintenance and calibration.

[0058] Furthermore, in S1, the positive direction of the X-axis is defined as the opposite direction of the antenna pointing direction, and the Y-axis and Z-axis are perpendicular to the Z-axis, thus establishing a rectangular coordinate system.

[0059] Furthermore, in S2-1, the theoretical derivation algorithm includes two types: "calculating and establishing the relationship between the distance of the maximum radiating oscillator from the origin and the working frequency, while keeping the distance between the maximum radiating oscillator and the object under test basically unchanged" and "approximately calculating the relationship between the phase center and the working frequency using the similarity principle, while keeping the distance between the phase center and the object under test basically unchanged".

[0060] One approach is to calculate and establish the relationship between the distance of the maximum radiating oscillator from the origin and the operating frequency, while keeping the distance between the maximum radiating oscillator and the object being measured essentially constant. For example:

[0061]

[0062] The derivation process is as follows:

[0063] like Figure 1 As shown, the apex angle of the log-periodic antenna is The scaling factor is The lowest frequency is The highest frequency is The longest oscillator is The shortest period is The spacing between adjacent oscillators is .

[0064] As we know from basic antenna knowledge:

[0065] When a log-periodic antenna is excited, each element exhibits different impedances under different frequency conditions:

[0066] When the oscillator length is much smaller than half the wavelength ( When the input impedance of the oscillator is capacitive, the current in the oscillator is very small, and the radiation is relatively small;

[0067] When the length of the oscillator is close to half the wavelength ( When the input impedance of the oscillator is purely resistive, the current in the oscillator is very large, the oscillator resonates, and effective radiation is formed;

[0068] When the oscillator length is much greater than half the wavelength ( When the input impedance is inductive, the oscillator region is almost unexcited and there is almost no radiation.

[0069] As we know from the basics of wave propagation:

[0070]

[0071] but:

[0072] ;

[0073] ;

[0074] As we know from basic antenna knowledge:

[0075]

[0076] further:

[0077]

[0078] but:

[0079] ;

[0080] Number of oscillators ;

[0081] When the working frequency is When the time is right, the corresponding oscillator length should be:

[0082] ;

[0083] Since the operating frequency of the antenna element is fixed, the rounding ratio needs to be set as required:

[0084] , ;

[0085] At this moment, the distance between the oscillator and the longest oscillator is:

[0086]

[0087] The distance from the origin of the coordinate system to the longest oscillator is:

[0088]

[0089] but:

[0090]

[0091] Based on this, the relationship between the antenna phase center and the actual operating frequency was confirmed;

[0092] Secondly, by utilizing the approximation principle, the relationship between the phase center and the operating frequency is fitted and calculated, while keeping the distance between the fitted phase center and the measured object essentially constant. For example:

[0093]

[0094] The derivation process is as follows:

[0095]

[0096] Based on this, the relationship between the antenna phase center and the actual operating frequency was confirmed;

[0097] Furthermore, in S2-2, as shown in Figure 3, the selected points... , , , ……, A scatter plot was created, and a regression equation was fitted using mathematical statistics. After significance testing and selection of the regression equation, the data was transformed into a coordinate system. Prediction algorithm;

[0098] Based on this, the relationship between the antenna phase center and the actual operating frequency was confirmed;

[0099] Furthermore, in S3, the candidate algorithm library for the phase center change relationship should include at least one of the S2-1 and S2-2 algorithms.

[0100] Furthermore, in S6, a robotic arm, an electric slide rail, or other structure are used as a carrier to control the antenna for compensated movement.

[0101] Furthermore, in S10, the measurement is performed using either a laser tracker or a high-precision radar.

[0102] Furthermore, in S11, the relevant data includes field strength, the state information of the object under test, operating frequency, phase center offset, and antenna movement distance.

[0103] Furthermore, in S12, periodic calibration and debugging are performed, including checking the operating status of mechanical devices and calibrating measuring equipment, to ensure the accuracy and stability of system test results.

[0104] The working principle and usage process of this invention are as follows: A three-dimensional rectangular coordinate system is established with the original phase center of the antenna as the origin O. Theoretical calculations, approximate calculations, mathematical statistics, and regression analysis are performed on the relationship between the antenna phase center and the operating frequency to obtain a library of candidate algorithms for the relationship between the phase center offset and the operating frequency. During testing, the origin O, i.e., the original phase center of the antenna, is placed at the starting test point. The initial distance between the origin O and the object under test is denoted as... Set the basic antenna parameters; before testing, inquire whether phase center offset compensation is required. If not, perform an uncompensated test; if yes, select the compensation algorithm for the test; at the start of the test, calculate the phase center offset at the actual operating frequency using the selected algorithm. ; Real-time adjustment of antenna position, the adjustment method is as follows This means that the antenna is compensated and adjusted in real time in the opposite direction of the phase center offset, and the moving distance is the absolute value of the phase center offset, so that the actual working distance is... Maintain the initial distance The results are kept equal until the test ends; relevant data are collected, and data analysis and processing are performed.

[0105] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An antenna control method that compensates for changes in distance from the object being measured as the phase center changes, characterized in that: Includes the following steps: S1. Establish a coordinate system: Establish a three-dimensional rectangular coordinate system with the original phase center of the antenna as the origin O; S2. Establish the phase center change relationship, with two methods to choose from: S2-1. Based on existing physical principles and antenna characteristics, establish a theoretical model to predict the relationship between the antenna phase center and the operating frequency, and analytically derive the relevant formula. ; S2-2. At different operating frequencies, collect data on the actual phase center position of the antenna. Based on mathematical statistics, fit and generate a regression relationship between the antenna phase center and the operating frequency. ; in, This is the actual operating frequency. It is the offset of the actual working phase center relative to the original position; S3. Establish a library of candidate algorithms; S4. Select the starting test point: Set the origin O, i.e., the original phase center of the antenna, to the starting test point. Record the initial distance between the origin O and the object under test as . ; S5. Set the antenna polarization, altitude, and frequency range parameters to prepare for testing; S6. Inquire whether to perform compensation adjustment for phase center offset; if yes, proceed to step S7; if no, proceed to step S8. S7. Select a test algorithm: Based on actual testing needs, select a suitable test algorithm from the algorithm library established by calculation; S8. Start testing; if option S6 is yes, proceed to step S9; if option S6 is no, proceed to step S11. S9. Calculate the actual offset: based on the actual operating frequency. The selected test The algorithm calculates the offset of the phase center relative to the original position in real time. Based on the initial distance At this time, the actual phase center is at a distance from the object being measured. for: ； S10. Real-time antenna position adjustment: The moving antenna compensates for phase center offset and maintains the actual working distance. equal to the initial distance The movement method is: That is, the antenna is moved in real time in the opposite direction of the phase center offset, and the moving distance is the absolute value of the phase center offset, until the test ends; S11. Test Completion and Result Analysis: After the test is completed, the test results are recorded and analyzed. S12. Regular maintenance of test equipment: Develop a maintenance plan based on the operating frequency and duration of the antenna test system, and perform regular maintenance and calibration.

2. The antenna control method as described in claim 1, wherein the distance to the object under test can be compensated for by changes in the phase center, is characterized in that: In S1, the positive direction of the X-axis is defined as the opposite direction of the antenna pointing direction, and the Y-axis and Z-axis are perpendicular to the X-axis, thus establishing a rectangular coordinate system.

3. The antenna control method as described in claim 1, wherein the distance to the object under test can be compensated for by changes in the phase center, is characterized in that: In S2-1, the theoretical derivation algorithm includes two types: "calculating and establishing the relationship between the distance of the maximum radiating oscillator from the origin and the working frequency, while keeping the distance between the maximum radiating oscillator and the object under test basically unchanged" and "approximately calculating the relationship between the phase center and the working frequency using the similarity principle, while keeping the distance between the phase center and the object under test basically unchanged".

4. The antenna control method as described in claim 1, wherein the distance to the object under test can be compensated for by changes in the phase center, is characterized in that: In S2-2, the regression analysis algorithm includes the steps of "scatter plot establishment", "regression relationship establishment", "significance test" and "regression equation selection".

5. The antenna control method as described in claim 1, wherein the distance to the object under test can be compensated for by changes in the phase center, is characterized in that: In S3, the candidate algorithm library for the phase center change relationship should include at least one of the S2-1 and S2-2 algorithms.

6. The antenna control method as described in claim 1, wherein the distance from the object to be measured can be compensated for as the phase center changes, is characterized in that: In step S10, measurement is performed using either a laser tracker or a high-precision radar.

7. The antenna control method as described in claim 1, wherein the distance to the object under test can be compensated for by changes in the phase center, is characterized in that: In S11, the relevant data includes field strength, the state information of the object under test, operating frequency, phase center offset, and antenna movement distance.

8. The antenna control method as described in claim 1, wherein the distance from the object to be measured can be compensated for by changes in the phase center, is characterized in that: In step S12, periodic calibration and debugging are performed, including checking the operating status of mechanical devices and calibrating measuring equipment to ensure the accuracy and stability of system test results.

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