Testing Method for Phase Deflection Characteristics of Array Element Channels in Phased Array Antenna

Abstract

The method for testing the phase deflection characteristics of the phased array antenna element channels proposed by the present invention is simple, reliable, consumes little hardware resources, and is easy to implement. The present invention is realized through the following technical solutions: Step 1, test preparation: First, perform spatial position calibration; Step 2, phase center test: Send the transmit trigger signal generated by the antenna test control system to the signal source through an optical fiber, and find the phase center of the antenna element to be tested through the method of the darkroom experiment turntable to form up and down beam patterns; Step 3, deflection phase characteristic test: Use the three-dimensional adjustment mechanism to rotate the turntable of the darkroom experiment on each axis, and send the received data of all receiving channels to the data acquisition unit in the test control system respectively, measure the actual phase center and phase deflection characteristics of the antenna element, find the phase deflection characteristics of the antenna element, draw the phase deflection characteristic diagram of the antenna element according to the azimuth angle and elevation angle of deflection, and correct the channel phase of the antenna element of the phased array based on this.

Description

Technical Field

[0001] The present invention relates to a method for testing the phase deflection characteristics of a phased array antenna element channel in the field of phased array antennas. Background Art

[0002] The phased array antenna system has become an essential and indispensable part of modern antenna radar systems, playing an increasingly important role in space TT&C, navigation and positioning, as well as radar. The antenna of a phased array radar consists of many antenna elements arranged in an array. The number of elements ranges from hundreds to tens of thousands, and these elements are regularly arranged on a plane to form an array antenna. The more the number of antenna elements, the more possible azimuths the beam can have in space. By utilizing the principle of electromagnetic wave coherence, the phase of the current fed to each radiation element can be controlled by a computer to synthesize beams with different phases. This type of radar uses a computer to control the phase shifters of the antenna array, thereby changing the phase distribution on the array surface, finally forming the required beam and making the beam scan in space according to a certain rule. The radiation element sends the received echo signal to the host computer to complete the radar's search, tracking, and measurement of the target. The tests of a phased array antenna include the tests of basic characteristics such as beam pointing, beam width, antenna gain, beam nulls, sidelobe position, and sidelobe level. In a phased array antenna system, the antenna pattern is an important parameter for describing the antenna characteristics. Electronic devices for different purposes often require antennas to have different directional characteristics, that is to say, the shape of the antenna pattern often determines the technical performance of the electronic device. When searching for and tracking a target, the entire antenna system can remain stationary, and the beam pointing of the antenna does not need to be controlled by a mechanical servo system. Instead, by controlling the phase of each element in the array antenna, the required antenna pattern and beam pointing can be obtained, enabling the beam to scan in a certain airspace according to a predetermined rule. The antenna pattern is an important parameter for describing the antenna performance. For an active phased array antenna, the measurement of its pattern is usually a complex and arduous task. Usually, the measurement of the antenna pattern needs to go through two stages: near-field measurement and far-field measurement. Based on the completion of the phase measurement of each element of the phased array antenna, the antenna pattern can be calculated by mathematical methods in the near-field measurement. However, since it is difficult to truly simulate the actual usage environment of the antenna in the near-field measurement, even if the performance of an ideal antenna can be calculated, the antenna in actual use still needs to be tested through far-field measurement. In the traditional measurement of the antenna pattern, usually a single-channel and single-frequency measurement method is adopted. This measurement method is cumbersome and time-consuming, and sometimes one-sided results may be obtained, making it difficult to comprehensively characterize the frequency band response characteristics of the antenna. Since the monopulse system requires the data information of the sum and difference channels, different channels must have their own independent antenna pattern data; and considering anti-jamming, the radar must be able to operate in a relatively wide frequency range, which requires the measurement of the antenna patterns of all channels and all operating frequencies. For a radar with such a complex system, if the traditional antenna pattern test method is still used, then the test work will be a huge project.

[0003] The observed values are all based on the phase center position of the array element antenna. In fact, the phase center of the array element antenna is inconsistent with its geometric center. The deviation of the antenna phase center has an impact on the relative positioning result, which can reach several millimeters to more than a dozen millimeters depending on the antenna performance. For measurements with very high accuracy requirements, this impact cannot be ignored. The phase deflection characteristic of the array element is for... By measuring the phase of the array element antenna, finding the physical position of the phase center of the array element antenna, and based on this, measuring the phase deflection characteristic of the array element antenna is an urgent problem to be solved in the design of the phased array antenna system. The phase deflection characteristic of the array element is mainly found by means of a turntable in an anechoic chamber to find the phase center of the array element antenna to be measured, and the phase deflection characteristic of the array element antenna is tested to find the phase deflection characteristic of the array element antenna, and based on this, the channel phase of the antenna elements of the phased array is corrected. Summary of the Invention

[0004] The object of the present invention is to provide a simple and reliable test method with small consumption of hardware resources for the problems of measuring the phase center of the array element antenna and the phase deflection characteristic of the array element antenna, which are the core in the design of the phased array antenna system, and can improve the reliability of the design of the phased array antenna system. By using this method, the phase center and phase deflection characteristic of the array element antenna can be conveniently measured in engineering practice, which is used to correct the beam forming of the phased array antenna to ensure that the engineering design of the phased array antenna system meets the index requirements.

[0005] The technical solution adopted by the present invention to solve its technical problems is: a test method for the phase deflection characteristic of the phased array antenna array element channel, which is characterized by including the following steps:

[0006] Step 1, test preparation: In the microwave anechoic chamber, install the positioning device, radio frequency device, control device, calibration antenna and the array element antenna to be measured on the anechoic chamber test turntable. Before starting the phase center test of the phased array antenna system, first perform spatial position calibration. Install the laser tracker above the tripod on the anechoic chamber floor, install the target balls above the polarization axes at the tops of the two ends of the anechoic chamber test turntable respectively, and calibrate their spatial coordinates;

[0007] Step 2, phase center test: After calibrating the spatial position coordinate information of each device in the phased array antenna system, perform the phase center test to give the basic design data for the design of the phased array antenna system. Send the emission trigger signal generated by the antenna test control system to the signal source through an optical fiber. The signal source outputs continuous wave radio frequency signals of different frequencies according to the timing requirements. Find the phase center of the array element antenna to be measured by means of the anechoic chamber test turntable, determine the array element coordinate values of the phased array antenna by using the measured phase center points of the array elements, and then form the up and down beams. According to the actual rotation angle of the anechoic chamber test turntable, obtain the beam pointing accuracy of the antenna under test;

[0008] Step 3: Deflection phase characteristic test: Set the deflection angle of the turntable in the anechoic chamber experiment through software. Taking the phase center O of the array element antenna as the origin of the coordinate system, rotate the array element antenna, and use the three-dimensional adjustment mechanism to adjust each axis of the turntable in the anechoic chamber experiment to align the phase center O of the antenna under test with the center point O' of the rotating array element antenna. Send the received data of all receiving channels to the data acquisition unit in the test control system respectively to collect the phase deflection data of the array element antenna. Then, use a combination of the turntable in the anechoic chamber experiment, a high-precision mount, and an optical measurement device to measure the actual phase center and phase deflection characteristics of the array element antenna, and conduct a deflection phase characteristic test on the array element antenna to find the phase deflection characteristics of the array element antenna. According to the phase characteristic data of the array element antenna deflection angle state, draw a phase deflection characteristic diagram of the array element antenna according to the azimuth angle and elevation angle of deflection, and based on this, correct the channel phase of the antenna elements of the phased array.

[0009] The beneficial effects of the present invention compared with the prior art are as follows:

[0010] The implementation method is relatively simple and consumes less hardware resources. In the present invention, the positioning device, radio frequency device, control device, calibration antenna, and the array element antenna to be measured are all installed on the turntable in the anechoic chamber experiment. The laser tracker is installed above the tripod on the anechoic chamber floor. The target balls are respectively installed above the polarization axes at the tops of both ends of the turntable in the anechoic chamber experiment, and their spatial coordinates are calibrated; the operation is simple and fast, which is convenient for system design. Through the method of anechoic chamber microwave testing, using a combination of the turntable, a high-precision mount, and an optical measurement device to measure the phase center and phase deflection characteristics of the array element antenna, only need to use the microwave anechoic chamber turntable and traditional instruments, and according to the designed test steps, the phase center of the antenna elements of the phased array and the phase deflection characteristic data of the array elements can be obtained. It is beneficial to improve the beamforming performance of system design and reduce the system design cost.

[0011] In the present invention, the transmission trigger signal generated by the antenna test control system is sent to the signal source through an optical fiber. The signal source outputs continuous wave radio frequency signals of different frequency points according to the timing requirements. The phase center of the antenna element to be measured is found by means of a darkroom experiment turntable. The element coordinate values of the phased array antenna are determined using the measured element phase center points, and then the up and down beams are formed. According to the actual angle turned by the darkroom experiment turntable, the beam pointing accuracy of the antenna under test is obtained. By measuring the phase center of the element and the phase deflection characteristics of the element, the implementation basis for beam forming of the phased array antenna is determined. The element coordinate values of the phased array antenna are determined using the measured element phase center points, and then the up and down beams are formed. Through the work process of testing - adjusting the phase matching data - retesting, the antenna pattern that meets the system requirements can be obtained. At the same time, using the measured phase deflection characteristic data of the element, the beam forming algorithm can be further corrected to make the beam forming performance better, thereby avoiding the randomness and blindness of system design and ensuring that the engineering design of the phased array antenna system meets the index requirements.

[0012] In the present invention, a combination of a darkroom experiment turntable, a high-precision mount, and an optical measurement device is used to measure the actual phase center and phase deflection characteristics of the element antenna, and a test on the phase deflection characteristics of the element antenna is carried out to find the phase deflection characteristics of the element antenna, and the basic design data for the design of the phased array antenna system are given, which is convenient for optimization and selection according to specific circumstances during the design of the phased array antenna. According to the phase characteristic data of the element antenna deflection angle state, a phase deflection characteristic diagram of the element antenna is drawn according to the azimuth angle and elevation angle of deflection. Based on this, the channel phase of the antenna element of the phased array is corrected. Using the element antenna phase deflection angle characteristic data, a phase deflection characteristic diagram of the element antenna can be drawn according to the azimuth angle and elevation angle of deflection. The phase characteristic data of the element antenna deflection angle state: can correct the channel phase of the element antenna: the actually measured phase center can effectively represent the actual phase relationship between each element. At high frequencies, the measured phase center is closer to the feed point than the theoretical phase center, improving the reliability of the design of the phased array antenna system. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described below in conjunction with the drawings and embodiments.

[0014] Figure 1 is a schematic diagram of the principle of testing the phase deflection characteristics of the antenna element of the phased array antenna of the present invention;

[0015] Figure 2 is Figure 1 a schematic flow diagram of the phase deflection characteristic test of

[0016] Figure 3 is a schematic coordinate measurement diagram of the test of the phase center of the antenna element and the phase deflection characteristics of the antenna element of the phased array antenna;

[0017] Figure 4 It is a schematic diagram of a test device for the phase center of the array element of a phased array antenna and the phase deflection characteristics of the array element;

[0018] Figure 5 It is a schematic diagram for testing the phase deflection characteristics of the array element antenna. Figure 5 (a) It is a schematic diagram of adjusting the turntable, Figure 5 (b) It is a schematic diagram of aligning the normal lines of the calibration antenna and the dipole antenna, Figure 5 (c) It is a schematic diagram for realizing the direction of the far-field point represented by (ψ, δ);

[0019] Figure 6 It is a schematic diagram of the network of the phase center of the array element of a phased array antenna and the phase deflection characteristics of the array element. Specific implementation mode

[0020] Refer to Figures 1-3 . According to the present invention, the following steps are adopted:

[0021] Step 1, test preparation: In a microwave anechoic chamber, install the positioning device, radio frequency device, control device, positioning device, radio frequency device, control device, calibration antenna and the array element antenna to be tested on the anechoic chamber test turntable. Before starting the phase center test of the phased array antenna system, first perform spatial position calibration. Set up the laser tracker above the tripod on the ground of the anechoic chamber, install the target balls above the polarization axes at the tops of the two ends of the anechoic chamber test turntable respectively, and calibrate their spatial coordinates;

[0022] Step 2, phase center test: After calibrating the spatial position coordinate information of each device in the phased array antenna system, perform the phase center test, and give the basic design data for the design of the phased array antenna system. Send the emission trigger signal generated by the antenna test control system to the signal source through an optical fiber. The signal source outputs continuous wave radio frequency signals of different frequency points according to the timing requirements. Find the phase center of the array element antenna to be tested through the anechoic chamber test turntable. Determine the array element coordinate values of the phased array antenna by using the measured phase center points of the array elements, and then form the up and down beams. According to the actual rotation angle of the anechoic chamber test turntable, obtain the beam pointing accuracy of the antenna under test;

[0023] Step 3, Deflection Phase Characteristic Test: Set the deflection angle of the turntable in the anechoic chamber experiment through software. Taking the phase center O of the array element antenna as the origin of the coordinate system, rotate the array element antenna, and use the three-axis of the turntable in the anechoic chamber experiment of the three-dimensional adjustment mechanism to align the phase center O of the antenna under test with the center point O' of the rotating array element antenna. Send the received data of all receiving channels to the data acquisition unit in the test control system respectively, collect the phase deflection data of the array element antenna, and then measure the actual phase center and phase deflection characteristics of the array element antenna by combining the turntable in the anechoic chamber experiment, the high-precision mount and the optical measurement equipment, and conduct the deflection phase characteristic test of the array element antenna to find the phase deflection characteristics of the array element antenna. According to the phase characteristic data of the array element antenna deflection angle state, draw the phase deflection characteristic diagram of the array element antenna according to the azimuth angle and elevation angle of deflection, and based on this, correct the channel phase of the antenna elements of the phased array.

[0024] After the calibration antenna and the antenna element under test are both installed on the turntable in the anechoic chamber, start the test in the microwave anechoic chamber. In the preparation stage, calibrate the spatial positions of the beacon antenna and the antenna under test. Output the spatial position information through the laser tracker and the target ball SMR, and establish Figure 3 the XYZ spatial coordinate system of the test end turntable target, the reference end turntable target and the laser tracker shown. Use the two-axis test turntable to conduct the phase center test, output the phase center spatial position coordinates according to the spatial coordinates of the antenna under test, and output the phase center of the phase pattern in the deflection phase characteristic test to complete the test.

[0025] Refer to Figure 4 . The positioning equipment includes: the test end turntable and the calibration end turntable that mainly realize the precise positioning of the antenna under test and the movement of the sampling position, and the network switch connected by the turntable driver LAN and TTL in a dual-way manner.

[0026] The RF equipment includes: the vector network analyzer connected to the antenna under test and the calibration antenna. The RF signal RF of the calibration antenna passes through the RFB vector network analyzer, and through the low-noise RF box, it forms a complete test link in cooperation with the RF cable.

[0027] The control equipment includes the control computer and the supporting control equipment and the vector network analyzer connected through the network switch, which are used to receive the trigger signals of the positioning equipment and the RF equipment, complete the timing interaction during the test process, and at the same time have the transmission of network control commands.

[0028] Before the phase center test of the phased array antenna system starts, the test uses a laser tracker erected above the tripod on the anechoic chamber floor. Install the target balls above the polarization axes at the tops of the two end turntables respectively. Erect the tracker to fix the target balls to confirm that each position target ball can be received during the test process. Calibrate and record the test three-dimensional space coordinates, calibrate the spatial position coordinate information of the above-mentioned equipment in the phased array antenna system, and calibrate the two spatial coordinates.

[0029] The establishment of the coordinate system and the recording process are as follows: Install targets on the AZ and EL axes of the two-end three-dimensional adjustment mechanism turntable and rotate. Record the position information of each test point and fit a circle. Use the center of the circle as the phase center O of the coordinate system and the rotation center point O'. Use each axis of the three-dimensional adjustment mechanism turntable to align the positions of O and O' for spatial calibration. Use a laser tracker and a test target to set up a calibration antenna and an antenna under test, and align the phase center of the calibration antenna with the rotation center of the turntable. At the same time, establish a test space coordinate system for phase center testing and phase deflection characteristic testing;

[0030] The measurement and control work mainly includes three stages: spatial position calibration in the test preparation stage, phase center testing in test stage 1, and deflection phase characteristic testing in test stage 2. Test stage 1: Under the established spatial coordinate system, use the turntable to scan and collect the spatial phase information, and calculate the phase center coordinates (x c , y c , z c ) of the antenna under test. According to the known spatial coordinate system, give the actual position information of the phase center relative to the antenna under test;

[0031] Test stage 2: On the basis of completing test 1, use the antenna under test with a known phase center and the calibration antenna to complete the deflection phase center test.

[0032] Refer to Figure 5 . The phase center and phase deflection characteristics of the array element antenna can be measured according to the following steps. Before the test, first install the adjustment turntable as shown in Figure 5 (a) to align the calibration antenna with the normal of the dipole antenna. As shown in Figure 5 (b), take (ψ, δ) on the coordinate system to represent the direction of the far-field point. The phase direction function of the antenna array element with 0 as the reference point is Ψ0(Ψ, δ). The phase direction function of the antenna array element with the phase center point of the antenna array element as the reference point is Ψ c (Ψ, δ) = Ψ0(Ψ, δ) - k(ux c + vy c + wz c ), where u = cosδsinψ, v = sinδ, w = cosδcosψ,

[0033] Among them, δ represents the elevation angle, Ψ represents the azimuth angle, Ψ0 represents the phase direction function of the antenna array element with 0 as the reference point, and Ψ c represents the phase direction function of the antenna array element with the phase center point of the antenna array element as the reference point, and k is the phase offset characteristic factor of the array element antenna.

[0034] Ψ cThe minimum change of (Ψ, δ) within a solid angle centered at (Ψ0, δ0). Then Ω is a region near (Ψ 0, , δ0) such that the (x c , y c , z c ) coordinate values that minimize Δ satisfy

[0035] a 11 x c + a 12 y c + a 13 z c = b1

[0036] a 21 x c + a 22 y c + a 23 z c = b2

[0037] a 31 x c + a 32 y c + a 33 z c = b3

[0038] Where:

[0039] a 11 = ∫ Ω (u - u0) 2 cosδdψdδ

[0040] a 22 = ∫ Ω (v - v0) 2 cosδdψdδ

[0041] a 33 = ∫ Ω (w - w0) 2 cosδdψdδ

[0042] a 12 = a 21 = ∫ Ω (u - u0)(v - v0)cosδdψdδ

[0043] a 13 = a 31 = ∫ Ω (u - u0)(w - w0)cosδdψdδ

[0044] a 23 = a 32 = ∫ Ω(v - v0)(w - w0)cosδdψdδ

[0045]

[0046]

[0047]

[0048] is: The position (x c , y c , z c ) of the phase center can be obtained by solving the system of equations from the measured phase pattern Ψ0(Ψ, δ). Among them, a11~a33, b1~b3 are intermediate variables for calculation, μ, w, v are direction vector values, and μ0, w0, v0 are direction vector values at point 0.

[0049] As Figure 5 (d) shows, the turntable rotates the array element antenna A with the phase center O of the array element antenna as the origin according to the angle set by the software, represents the direction of the far - field point by (ψ, δ), and collects the phase deflection data of the array element antenna as: {phase deflection correction value of the array element antenna (ψ, δ)}.

[0050] Refer to Figure 6 . The phase of the array element antenna channel = calibration phase + spatial phase + {phase deflection correction value of the array element antenna (ψ, δ)}. The phase deflection characteristic data of the array element antenna can be plotted as a phase deflection characteristic diagram of the array element antenna according to the azimuth angle and elevation angle of deflection. The deflection angle characteristic data between sampling points can be obtained by interpolation using this data. The phase of the array element antenna channel can be corrected using the phase deflection angle characteristic data of the array element antenna: the phase of the array element antenna channel = calibration phase + spatial phase + {phase deflection correction value of the array element antenna (ψ, δ)}, and {phase deflection correction value of the array element antenna (ψ, δ)} is used to improve the beam - forming performance of the phased - array antenna based on this.

[0051] The above - mentioned are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several deformations and improvements can be made, and these changes and alterations should be regarded as belonging to the protection scope of the present invention.

Claims

1. A method for testing the phase deflection characteristics of a phased array antenna element channel, characterized in that The steps are as follows: Step 1, Test Preparation: In the microwave anechoic chamber, install the positioning device, radio frequency device, control device, calibration antenna and the antenna under test on the anechoic chamber test turntable. Before starting the phase center test of the phased array antenna system, first perform spatial position calibration. Set up the laser tracker above the tripod on the anechoic chamber floor, install the target balls above the polarization axes at the tops of the two ends of the anechoic chamber test turntable respectively, and calibrate their spatial coordinates; Step 2, Phase Center Test: After calibrating the spatial position coordinate information of each device in the phased array antenna system, perform the phase center test to give the basic design data for the design of the phased array antenna system. Send the emission trigger signal generated by the antenna test control system to the signal source through optical fiber. The signal source outputs continuous wave radio frequency signals of different frequencies according to the timing requirements. Find the phase center of the antenna under test through the anechoic chamber test turntable. Determine the element coordinate values of the phased array antenna using the measured element phase center points, and then form the up and down beams. According to the actual rotation angle of the anechoic chamber test turntable, obtain the beam pointing accuracy of the antenna under test; Step 3, Deflection Phase Characteristic Test: Set the deflection angle of the anechoic chamber test turntable through software. In the coordinate system with the phase center O of the element antenna as the origin, rotate the element antenna. Use the three-axis adjustment mechanism of the anechoic chamber test turntable to align the phase center O of the antenna under test with the center point O' of the rotated element antenna. Send the received data of all receiving channels to the data acquisition unit in the test control system respectively to collect the phase deflection data of the element antenna. Then, use a combination of the anechoic chamber test turntable, high-precision mount and optical measurement equipment to measure the actual phase center and phase deflection characteristics of the element antenna, and perform the deflection phase characteristic test of the element antenna to find the phase deflection characteristics of the element antenna. According to the phase characteristic data of the element antenna deflection angle state, draw the phase deflection characteristic diagram of the element antenna according to the azimuth angle and elevation angle of deflection, and based on this, correct the channel phase of the antenna elements of the phased array.

2. The method for testing the phase deflection characteristics of the phased array antenna element channels according to claim 1, characterized in that: After the calibration antenna and the antenna under test are both installed on the anechoic chamber turntable, start the test in the microwave anechoic chamber. Perform the spatial position calibration of the beacon antenna and the antenna under test in the preparation stage. Output the spatial position information through the laser tracker and the target ball SMR, and establish the XYZ spatial coordinate system of the test end turntable target, reference end turntable target and laser tracker. Use the two-axis test turntable to perform the phase center test, output the phase center spatial position coordinates according to the spatial coordinates of the antenna under test, and output the phase center of the phase direction diagram in the deflection phase characteristic test to complete the test.

3. The method for testing the phase deflection characteristics of the phased array antenna element channels according to claim 1, characterized in that: The positioning device includes: a test end turntable and a calibration end turntable that mainly achieve precise positioning of the antenna under test and movement of the sampling position, and a network switch connected by LAN and TTL of the turntable driver; the RF device includes: a vector network analyzer connected to the antenna under test and the calibration antenna, the RF signal RF of the calibration antenna passes through the RFB vector network analyzer, and through a low-noise RF box, and forms a complete test link in cooperation with RF cables; the control device includes a control computer and supporting control devices and a vector network analyzer connected through a network switch, which is used to receive the trigger signals of the positioning device and the RF device, complete the timing interaction during the test process, and simultaneously transmit network control commands.

4. The method for testing the phase deflection characteristics of the phased array antenna element channels according to claim 1, characterized in that: Before the phase center test of the phased array antenna system begins, the test is carried out by using a laser tracker installed above a tripod on the darkroom floor. The target balls are respectively installed above the polarization axes at the tops of the two end turntables. The tracker is set up to fix the target balls to confirm that the target balls at each position during the test can be received. The three-dimensional coordinates of the test are calibrated and recorded, and the spatial position coordinate information of the above-mentioned devices in the phased array antenna system is calibrated, and the spatial coordinates of the two are calibrated.

5. The method for testing the phase deflection characteristics of the phased array antenna element channels according to claim 1, characterized in that: During the establishment of the coordinate system and the recording process: the target is installed on the AZ and EL axes of the two-end three-dimensional adjustment mechanism turntable and rotated, the position information of each test point is recorded and a circle is fitted. The phase center O of the coordinate system and the rotation center point O' are the center of the circle. Using the axes of the three-dimensional adjustment mechanism turntable, align the points O and O' for spatial position calibration. Using the laser tracker and the test target, set up the calibration antenna and the antenna under test, align the phase center of the calibration antenna with the rotation center of the turntable, and at the same time establish a test space coordinate system for phase center test and phase deflection characteristic test; The measurement and control work includes space position calibration in the test preparation stage, and is divided into three stages: the phase center test in Test Stage 1 and the deflected phase characteristic test in Test Stage 2. Test Stage 1: Under the established space coordinate system, use a turntable to scan and collect the space phase information, and calculate the phase center coordinates of the antenna under test. , and give the actual position information of the phase center relative to the antenna under test according to the known space coordinate system; Test Stage 2: On the basis of completing Test 1, use the antenna under test with a known phase center and the calibration antenna to complete the deflected phase center test.

6. The method for testing the phase deflection characteristics of the phased array antenna element channels according to claim 1, characterized in that: Before the test, first install and adjust the turntable to align the calibration antenna with the normal of the dipole antenna. On the coordinate system, take to represent the direction of the far-field point. The phase direction function of the antenna array element with point O as the reference point is , and the phase direction function of the antenna array element with the phase center point of the antenna array element as the reference point is , , , ; Among them, represents the pitch angle, represents the azimuth angle, represents the antenna array element phase direction function with point O as the reference point, represents the phase center point of the antenna array element, and k is the phase offset characteristic factor of the array element antenna.

7. The method for testing the phase deflection characteristics of the phased array antenna element channels according to claim 6, characterized in that: The minimum change within a solid angle centered on is such that, for , is a region near which, for the minimum of Δ, the coordinate values satisfy: Among them: is: ; From the measured phase pattern The position of the phase center can be obtained by solving the system of equations ; where ~ and ~ are intermediate variables for calculation u and w and v are direction vector values and and are direction vector values at point O 8. The method for testing the phase deflection characteristics of the phased array antenna element channels according to claim 1, characterized in that: The turntable rotates the array antenna A with the phase center O of the array antenna as the origin according to the angle set by the software, and uses to represent the direction of the far-field point, and the collected array antenna phase deflection data is: {array antenna phase deflection correction value }.

9. The method for testing the phase deflection characteristics of the phased array antenna element channels according to claim 1, characterized in that: Element antenna channel phase = calibration phase + spatial phase + {element antenna phase deflection correction value } The element antenna phase deflection angle characteristic data is plotted into an element antenna phase deflection characteristic diagram according to the azimuth angle and elevation angle of deflection. The deflection angle characteristic data between sampling points is obtained by interpolation using this data.

10. The method for testing the phase deflection characteristics of the phased array antenna element channels according to claim 1, characterized in that: Using the characteristic data of the phase deflection angle of the array element antenna to correct the phase of the array element antenna channel: Array element antenna channel phase = calibration phase + spatial phase + {array element antenna phase deflection correction value }, {array element antenna phase deflection correction value } and improving the beamforming performance of the phased array antenna based on this.

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