An automated calibration system and method for compact range quiet zone plane wave amplitude and phase characteristics

Abstract

The application discloses a kind of automatic calibration system and method of tight field quiet zone plane wave amplitude and phase characteristics, the system includes: microwave amplitude and phase unit, scanning equipment unit and central control unit;Microwave amplitude and phase unit is used to receive signal and carry out amplitude and phase measurement to the signal;Scanning equipment unit is used to control the receiving position and attitude of detection probe;Central control unit is used to remotely control microwave amplitude and phase unit and scanning equipment unit, real-time analysis amplitude and phase data, automatically calculate quiet zone characteristics.According to scanning data, complete three index quantization of quiet zone field amplitude unevenness, quiet zone field phase unevenness and quiet zone field cross polarization, according to the result to judge the performance of tight field test system, it has reference intention for tight field initial inspection and reinspection, the application can also help user initial inspection and subsequent reinspection tight field test system performance.

Description

Technical Field

[0001] This invention relates to calibration methods, and more specifically, to an automated calibration system and method for the amplitude and phase characteristics of plane waves in a compressed field static region. Background Technology

[0002] Compacted field testing is a widely used method for testing the characteristics of high-performance radar antennas and radomes, as well as for radar target RCS testing. It boasts advantages such as wide range, high testing accuracy, and ease of use. Since the 1990s, companies worldwide have been developing various types of large-scale compacted fields. Currently, dozens of compacted fields have been built in China, varying in type and quiet zone size, resulting in significant differences in quiet zone performance. The quiet zone performance of compacted fields is currently verified by the developing units themselves. Users generally lack sufficient understanding of the design and adjustment of compacted fields, and are not clear about the details of the testing process. They can only rely on the testing reports from the developers to understand the performance of the compacted field. Furthermore, developers often use different post-processing methods for test data related to performance indicators such as amplitude ripple and amplitude taper, which may lead to concerns among users regarding the actual performance of the quiet zone. A compacted field system ultimately aims to provide a uniform plane wave with high polarization purity. Therefore, the three most crucial indicators for evaluating a compacted field system are: amplitude irregularity of the static field, phase irregularity of the static field, and cross-polarization of the static field. The first two indicators reflect the uniformity of the plane wave, while the last one reflects its polarization purity. Testing the performance of a compacted field generally refers to evaluating these three indicators.

[0003] This invention constructs a large-scale, compact field quiet zone performance automated calibration system, mainly composed of a microwave amplitude and phase system, a scanning equipment system, and a central control system. The microwave amplitude and phase system measures the amplitude and phase of the signal received by the probe. The scanning equipment system controls the receiving position and attitude of the detection probe. The central control system remotely controls the microwave amplitude and phase system and the scanning equipment system, and processes the amplitude and phase data to automatically calculate the quiet zone characteristics. This system can automatically calibrate the plane wave amplitude and phase characteristics in the quiet zone of a compact field. The calibration results are valuable for helping users adjust the phase center, pitch angle, and other settings of the feed source to achieve optimal quiet zone performance. Summary of the Invention

[0004] The purpose of this invention is to provide an automated calibration system and method for the amplitude and phase characteristics of plane waves in a compressed field static region.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An automated calibration system for the amplitude and phase characteristics of plane waves in a compressed field static region includes: a microwave amplitude and phase unit, a scanning device unit, and a central control unit;

[0007] A microwave amplitude and phase unit is used to receive signals and measure the amplitude and phase of the signals;

[0008] The scanning device unit is used to control the receiving position and orientation of the detection probe.

[0009] The central control unit is used for remote control of the microwave amplitude and phase unit and the scanning equipment unit, real-time analysis of amplitude and phase data, and automated calculation of quiet zone characteristics.

[0010] Optionally, the central control unit includes a main control computer, which includes a remote control module and a data processing module;

[0011] The scanning equipment unit includes a scanning gantry and a control chassis. The control chassis provides an external interface for exchanging scanning position parameters, polarization adjustments, position information, and test data.

[0012] Optionally, the calibration range is 0.5 GHz to 110 GHz.

[0013] Optionally, for close-range testing in the 0.5 GHz to 40 GHz band, the microwave amplitude and phase system includes a signal source, a vector network analyzer, and a receiving antenna.

[0014] Optionally, for long-distance testing in the 0.5 GHz to 40 GHz band, the microwave amplitude and phase system includes a signal source, a power amplifier, a vector network analyzer, a low-noise amplifier, and a receiving antenna.

[0015] Optionally, for tests with calibration frequencies higher than 40 GHz, a low-noise amplifier is connected at the signal receiver and a power amplifier is connected at the signal transmitter.

[0016] Optionally, the remote control module is used to control the selection of the rotating shaft, the start and end positions of the movement, the running speed, and the running status indication of the scanning device unit.

[0017] Optionally, the remote control module is used to set the instrument parameters of the signal source and vector network analyzer in the microwave amplitude and phase unit. The parameters include scan type, measurement mode, test frequency, scan time and number of points.

[0018] An automated calibration method for the amplitude and phase characteristics of plane waves in a compressed field quiet zone includes: S1, installing a scanning frame device equipped with an automated calibration system, determining the horizontal direction as the X direction, the vertical direction as the Y direction, the electromagnetic wave propagation direction as the Z direction, the cross section to be calibrated as perpendicular to the Z axis, and 0 as the center of the quiet zone;

[0019] S2. Select the calibration system configuration according to the type of compressed field being calibrated, connect the system using a stable phase cable, and preheat the system.

[0020] S3. Adjust the scanning frame relative to the incoming wave attitude so that the scanning stroke is perpendicular to the direction of the incoming wave. The central control system officially calibrates the data acquisition and completes the calculation of the static field amplitude unevenness, static field phase unevenness, and static field cross-polarization.

[0021] S4. Set the frequency to be calibrated, and record the logarithmic value of the field strength amplitude and the linear value of the field strength phase at the corresponding calibration position when the scanning frame is in the first posture state.

[0022] S5. Change the frequency point to be calibrated, repeat step S4, and obtain the amplitude and phase test data of all calibrated frequencies within the working frequency range of the compressed field feed in the first posture state of the scanning frame.

[0023] S6. Change the second scanning posture and repeat steps S4 to S5 to obtain the amplitude and phase test data of all calibrated frequencies within the working frequency range of the compressed field feed source under the second scanning posture.

[0024] S7. Change the polarization of the feed antenna and the receiving antenna, and repeat steps S4 to S6.

[0025] S8. Replace the feed source with another frequency band and repeat steps S4 to S7.

[0026] S9. Change the calibration section position and repeat steps S3 to S8 until all main polarization calibration states are completed.

[0027] Optionally, step S3 further includes setting the system operating frequency to the highest operating frequency of the compressed field being calibrated; setting microwave amplitude and phase system parameters, including transmit power, intermediate frequency bandwidth and measurement channel parameters, and controlling the feed and receiving antenna polarization to be consistent;

[0028] The test time and test compensation parameters are set according to the frequency being calibrated. The corresponding data curves are plotted using the data obtained from the calibration system. The scanning frame is controlled to make corresponding attitude adjustments according to the amplitude and phase distribution trends, so that the scanning stroke is perpendicular to the direction of the incoming wave. After the adjustment is in place, the central control system begins to formally calibrate and collect data, and completes the calculation of the amplitude unevenness, phase unevenness, and cross-polarization of the quiet field.

[0029] The beneficial effects of this invention are as follows:

[0030] This invention discloses an automated calibration system for the amplitude and phase characteristics of a plane wave in a compressed field still zone, comprising a microwave amplitude and phase unit, a scanning device unit, and a central control unit. Based on the scanning data, it quantifies three indicators: amplitude unevenness, phase unevenness, and cross-polarization of the still field. The results are used to evaluate the performance of the compressed field testing system, providing a reference for initial and subsequent testing of the compressed field. This invention can also assist users in the initial and subsequent testing of the compressed field testing system's performance. Simultaneously, the central control unit employs an "abstraction + strategy pattern" design, encapsulating changes in instrument models, decoupling algorithms, and reducing the increased system development workload caused by the diversity of compressed fields. Attached Figure Description

[0031] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0032] Figure 1 A schematic diagram of the existing probe scanning method is shown.

[0033] Figure 2 The overall block diagram of the large compact field static zone performance calibration system is shown.

[0034] Figure 3 The system configuration block diagram for close-range calibration testing is shown.

[0035] Figure 4 The system configuration block diagram for remote calibration testing is shown.

[0036] Figure 5 A schematic diagram of the scanning gantry control is shown.

[0037] Figure 6 The diagram shows the control schematic of the signal source and vector network analyzer.

[0038] Figure 7 A schematic diagram showing the calibration results of the calibration method of the present invention is presented. Detailed Implementation

[0039] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments and accompanying drawings, further explains the invention. Similar components in the drawings are indicated by the same reference numerals. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention.

[0040] Compacted field testing is a widely used method for testing the characteristics of high-performance radar antennas and radomes, as well as the RCS of radar targets. It offers advantages such as wide coverage, high testing accuracy, and ease of use. Currently, dozens of compacted fields have been built in China, with varying types and quiet zone sizes, resulting in significant differences in quiet zone performance. Therefore, there is an urgent need to develop a large-scale calibration system to calibrate the quiet zone performance of newly built or existing large-scale compacted fields, assisting users in initial and subsequent re-evaluation of the compacted field testing system's performance. This invention constructs an automated calibration system for the quiet zone performance of large-scale compacted fields, enabling automated calibration of the quiet zone performance of compacted fields, thereby ensuring the accuracy and reliability of RCS test results for antennas, radomes, and targets used in enterprise products.

[0041] There are various methods for calibrating the performance of the quiet zone in a compressed field. The most commonly used method internationally is the probe scanning method, which involves directly testing and evaluating the amplitude and phase of the plane wave field in the compressed field test area using a standard probe. Figure 1 As shown.

[0042] like Figure 2-7 As shown, the first embodiment of the present invention provides an automated calibration system for the amplitude and phase characteristics of a plane wave in a compressed field quiet zone, comprising: a microwave amplitude and phase unit, a scanning device unit, and a central control unit;

[0043] A microwave amplitude and phase unit is used to receive signals and measure the amplitude and phase of the signals;

[0044] The scanning device unit is used to control the receiving position and orientation of the detection probe.

[0045] The central control unit is used for remote control of the microwave amplitude and phase unit and the scanning equipment unit, real-time analysis of amplitude and phase data, and automated calculation of quiet zone characteristics.

[0046] In a specific example, the microwave amplitude and phase unit performs amplitude and phase measurements on the signal received by the probe, and mainly consists of a transmitting signal source, a receiving probe, and a signal receiver. The scanning device unit controls the receiving position and orientation of the detection probe and mainly consists of a scanning frame and a control chassis. The control chassis provides an external interface to exchange scanning position parameters, polarization adjustment, position information, and test data. The central control unit enables remote control of the microwave amplitude and phase unit and the scanning device unit, completing real-time measurement and amplitude and phase data analysis, and automating the calculation of quiet zone characteristics.

[0047] Specifically, a compacted field system ultimately aims to provide a uniform plane wave with high polarization purity. Therefore, the three core indicators for evaluating a compacted field system are: amplitude irregularity in the static field, phase irregularity in the static field, and cross-polarization in the static field. The first two indicators reflect the uniformity of the plane wave, while the last reflects its polarization purity. Amplitude irregularity is defined as the difference between the maximum and minimum amplitude values ​​on the intersection lines of the detection plane and the horizontal and vertical planes. Phase irregularity is defined as the difference between the maximum and minimum phase values ​​on the intersection lines of the detection plane and the horizontal and vertical planes. Cross-polarization is defined as the ratio of the measured cross-polarization value to the measured value of the same polarization; generally, the maximum value of this ratio on the detection plane is used to define the cross-polarization of that cross section. Common factors causing amplitude and phase irregularities include flatness, taper, and waviness.

[0048] In one alternative implementation, the central control unit uses an "abstraction + strategy pattern" and includes a master computer, which includes a remote control module and a data processing module.

[0049] The scanning equipment unit includes a scanning gantry and a control chassis. The control chassis provides an external interface for exchanging scanning position parameters, polarization adjustments, position information, and test data.

[0050] In one optional implementation, the system calibration range is 0.5 GHz to 110 GHz.

[0051] In one alternative implementation, for close-range testing in the 0.5 GHz to 40 GHz band, the microwave amplitude-phase system includes a signal source, a vector network analyzer, and a receiving antenna.

[0052] In one alternative implementation, for long-distance testing in the 0.5 GHz to 40 GHz band, the microwave amplitude-phase system includes a signal source, a power amplifier, a vector network analyzer, a low-noise amplifier, and a receiving antenna.

[0053] In one alternative implementation, for tests with calibration frequencies above 40 GHz, a low-noise amplifier is connected at the signal receiver and a power amplifier is connected at the signal transmitter.

[0054] In one optional implementation, the remote control module is used to control the selection of the rotating shaft, the start and end positions of the motion, the running speed, and the running status indication of the scanning device unit.

[0055] In one optional implementation, the remote control module is used to set the instrument parameters of the signal source and vector network analyzer in the microwave amplitude and phase unit, including scan type, measurement mode, test frequency, scan time and number of points.

[0056] The second embodiment of the present invention provides an automated calibration method for the amplitude and phase characteristics of plane waves in a compact field quiet zone, comprising: S1, installing a scanning frame device equipped with an automated calibration system, determining the horizontal direction as the X direction, the vertical direction as the Y direction, the electromagnetic wave propagation direction as the Z direction, the cross section to be calibrated as perpendicular to the Z axis, and 0 as the center of the quiet zone;

[0057] S2. Select the calibration system configuration according to the type of compressed field being calibrated, connect the system using a stable phase cable, and preheat the system.

[0058] S3. Adjust the scanning frame relative to the incoming wave attitude so that the scanning stroke is perpendicular to the direction of the incoming wave. The central control system officially calibrates the data acquisition and completes the calculation of the static field amplitude unevenness, static field phase unevenness, and static field cross-polarization.

[0059] S4. Set the frequency to be calibrated, and record the logarithmic value of the field strength amplitude and the linear value of the field strength phase at the corresponding calibration position when the scanning frame is in the first posture state.

[0060] S5. Change the frequency point to be calibrated, repeat step S4, and obtain the amplitude and phase test data of all calibrated frequencies within the working frequency range of the compressed field feed in the first posture state of the scanning frame.

[0061] S6. Change the second scanning posture and repeat steps S4 to S5 to obtain the amplitude and phase test data of all calibrated frequencies within the working frequency range of the compressed field feed source under the second scanning posture.

[0062] S7. Change the polarization of the feed antenna and the receiving antenna, and repeat steps S4 to S6.

[0063] S8. Replace the feed source with another frequency band and repeat steps S4 to S7.

[0064] S9. Change the calibration section position and repeat steps S3 to S8 until all main polarization calibration states are completed.

[0065] In an optional implementation, step S3 further includes setting the system operating frequency to the highest operating frequency of the compressed field being calibrated; setting microwave amplitude and phase system parameters, including transmit power, intermediate frequency bandwidth and measurement channel parameters, and controlling the feed and receiving antenna polarization to be consistent;

[0066] The test time and test compensation parameters are set according to the frequency being calibrated. The corresponding data curves are plotted using the data obtained from the calibration system. The scanning frame is controlled to make corresponding attitude adjustments according to the amplitude and phase distribution trends, so that the scanning stroke is perpendicular to the direction of the incoming wave. After the adjustment is in place, the central control system begins to formally calibrate and collect data, and completes the calculation of the amplitude unevenness, phase unevenness, and cross-polarization of the quiet field.

[0067] In the first specific embodiment, the present invention constructs a large-scale compact field static zone performance automated calibration system, mainly composed of a microwave amplitude and phase system, a scanning equipment system, and a central control system, such as... Figure 2 As shown.

[0068] The microwave amplitude and phase system enables amplitude and phase measurement of the signal received by the probe. It mainly consists of a transmitting signal source, a receiving probe, and a signal receiver.

[0069] In the calibration of plane wave amplitude and phase characteristics in the quiet zone of a compact field, the calibration range is typically 0.5 GHz to 110 GHz. For close-range testing in the 0.5 GHz to 40 GHz band, the microwave amplitude and phase system consists of a signal source, a vector network analyzer, and a receiving antenna, such as... Figure 3 As shown.

[0070] For long-distance testing in the 0.5 GHz to 40 GHz band, the microwave amplitude and phase system consists of a signal source, power amplifier, vector network analyzer, low-noise amplifier, and receiving antenna, such as... Figure 4 As shown.

[0071] When the calibration frequency is higher than 40GHz, the signal attenuation increases, so power amplifiers and low-noise amplifiers will be considered at both the transmitting and receiving ends.

[0072] The scanning equipment system can control the receiving position and attitude of the detection probe, and mainly consists of a scanning frame and a control chassis. The control chassis provides an external interface to exchange scanning position parameters, polarization adjustment, position information, and test data.

[0073] The central control system enables remote control of the microwave amplitude and phase system and the scanning equipment system, completing real-time measurement and amplitude and phase data analysis, and automating the calculation of still zone characteristics. The central control system includes a remote control module and a data processing module. The remote control module controls the scanning equipment's axis selection, start and end positions, operating speed, and operating status indications, such as... Figure 5 As shown;

[0074] For microwave amplitude and phase systems, it is necessary to set the instrument parameters for the signal source and vector network analyzer, including common scan types, measurement modes, test frequencies, scan times, and number of points, such as... Figure 6 As shown.

[0075] A compact field system ultimately aims to provide a uniform plane wave with high polarization purity. Therefore, the three core indicators for evaluating a compact field system are: amplitude irregularity in the static field, phase irregularity in the static field, and cross-polarization in the static field. The first two indicators reflect the uniformity of the plane wave, while the last one reflects its polarization purity. Amplitude irregularity is defined as the difference between the maximum and minimum amplitude values ​​on the intersection lines of the detection plane and the horizontal and vertical planes. Phase irregularity is defined as the difference between the maximum and minimum phase values ​​on the intersection lines of the detection plane and the horizontal and vertical planes. Cross-polarization is defined as the ratio of the measured cross-polarization value to the measured value of the same polarization; generally, the maximum value of this ratio on the detection plane is used to define the cross-polarization of that cross section. Common factors causing amplitude and phase irregularities include flatness, taper, and waviness.

[0076] Flatness data processing involves statistically analyzing the difference between the maximum and minimum values ​​in the measurement data, as shown in the following formula.

[0077] A fi =A ij-max -A ij-min

[0078] Tapering data processing involves statistically analyzing the difference between the maximum and minimum values ​​of the fitted data, as shown in the following formula.

[0079] A ti =A' ij-max -A' ij-min

[0080] Ripple data processing involves statistically analyzing the difference between the maximum and minimum values ​​of the measured data and the fitted data, as shown in the following formula.

[0081] A ri =±[(A ij -A' ij ) max -(A ij -A' ij ) min ] / 2

[0082] The data processing module acquires the scan data from the vector network analyzer, performs quadratic term fitting of the data curve using the least squares method, calculates the limit curve based on an upper limit of 1dB for amplitude variation and 10dB for phase variation, and performs corresponding calculations based on the definitions of flatness, taper, and waviness. This allows for a direct visual inspection of whether the amplitude and phase unevenness are within the standard range, enabling automated viewing of the compaction field calibration results. Figure 7 As shown.

[0083] In a second specific embodiment, this invention provides an automated calibration method for the amplitude and phase characteristics of a plane wave in the quiet zone of a compressed field. The invention first designs an automated calibration system for the amplitude and phase characteristics of a plane wave in the quiet zone of a compressed field, comprising a microwave amplitude and phase unit, a scanning device unit, and a central control unit. Based on the scanning data, three indicators—quiet field amplitude unevenness, quiet field phase unevenness, and quiet field cross-polarization—are quantified. The performance of the compressed field test system is evaluated based on the calibration results. During the calibration process, by analyzing the changing trends of the test curves, it is possible to determine whether there are problems with the pitch angle of the compressed field feed, the phase center position, and the edge teeth of the compressed field. Adjustments can be made accordingly until the various indicators of the test curve basically meet the design requirements. The specific implementation steps are as follows:

[0084] ① Within the quiet zone of the compressed field, use a laser tracker to precisely position and install the scanning frame equipment, defining the horizontal direction as X, the vertical direction as Y, the electromagnetic wave propagation direction as Z, the cross-section to be calibrated as perpendicular to the Z-axis, and 0 as the center of the quiet zone. Ensure the test position meets calibration requirements by designing markers within the dark chamber of the compressed field and using the laser tracker for positioning.

[0085] ② Select the appropriate calibration system configuration according to the type of compressed field being calibrated, connect the system using a compliant amplitude-stabilized phase cable, and preheat the system according to the equipment manual.

[0086] ③ Adjust the scanning frame attitude relative to the incoming wave, and set the system operating frequency to the highest operating frequency f of the compressed field being calibrated. max Set microwave amplitude and phase unit parameters, including appropriate transmit power, intermediate frequency bandwidth, measurement channel, etc., and control the polarization mode of the feed and receiving antenna to be consistent; set appropriate test time, test step size, etc. according to the frequency being calibrated, and the test compensation is generally set to one-quarter of the wavelength; use the amplitude and phase data obtained by the calibration system to draw the corresponding data curves, and control the scanning frame to make corresponding attitude adjustments according to the amplitude and phase distribution trend, so that the scanning stroke is perpendicular to the direction of the incoming wave. After the adjustment is in place, the central control system begins to formally calibrate and collect data, and completes the calculation of the amplitude unevenness, phase unevenness, and cross-polarization of the quiet field.

[0087] ④ Set the calibrated frequency f1, and record the logarithmic value A of the field strength amplitude at the corresponding calibration position Xj measured by the receiving device when the scanning frame is in attitude 1 (e.g., horizontal direction of the calibrated section). 1j The phase linearity p with the field strength 1j .

[0088] ⑤ Change the frequency point f being calibrated i Repeat step ④ until the amplitude and phase test data A of all calibrated frequencies within the working frequency range of the feed source under scanning posture 1 is obtained. ij and P ij .

[0089] ⑥ Change the scanning posture 2 (e.g., the vertical direction of the cross section being calibrated), and repeat steps ④ to ⑤ until the amplitude and phase test data of all calibrated frequencies within the working frequency range of the feed source under the scanning posture 2 state are obtained.

[0090] ⑦ Change the polarization of the feed antenna and the receiving antenna, and repeat steps ④ to ⑥.

[0091] ⑧ Replace with a feed source in a different frequency band and repeat steps ④ to ⑦.

[0092] ⑨ Change the calibration section position and repeat steps ③ to ⑧ until all principal polarization calibration states are completed.

[0093] In the central control unit, considering the different models of instruments used, including signal sources and vector network analyzers, an "abstraction + strategy model" is used to encapsulate the impact of instrument model changes in order to coordinate instrument control. This method defines microwave amplitude and phase system control algorithms, encapsulates them separately, and allows them to be interchangeable. Changes in the encapsulated algorithms do not affect the central control system controlling the microwave amplitude and phase system.

[0094] With the development of stealth and anti-stealth technologies and satellite technology, the requirements for the accuracy and functionality of high-performance radar antennas, radome characteristic testing, and radar target RCS testing are becoming increasingly stringent. This has led to a rising demand in China for large-scale quiet zone compact testing systems. Dozens of compact testing systems have been built domestically, varying in type and quiet zone size, and exhibiting significant differences in quiet zone performance. For newly built or existing large-scale compact testing systems, this invention can assist users in the initial and subsequent re-inspection of the performance of the compact testing system.

[0095] This invention designs an automated calibration system and method for the amplitude and phase characteristics of plane waves in the quiet zone of a compressed field, comprising a microwave amplitude and phase system, a scanning equipment system, and a central control system. After the calibration equipment is fully installed, it can quantify three indicators—amplitude irregularity, phase irregularity, and cross-polarization—based on the scanning data, providing real-time evaluation of the performance of the compressed field testing system. This has reference value for initial and re-inspection of compressed fields. Simultaneously, the central control system employs an "abstraction + strategy pattern" design, encapsulating changes in instrument models, decoupling algorithms, and reducing the increased system development workload caused by the diversity of compressed fields.

[0096] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. An automated calibration system for the amplitude and phase characteristics of a plane wave in a compressed field static region, characterized in that, The system is used to perform an automated calibration method for the amplitude and phase characteristics of plane waves in the static region of a compressed field, the method including: S1. Install the scanning frame equipment, determine the horizontal direction as X, the vertical direction as Y, the electromagnetic wave propagation direction as Z, the cross section to be calibrated as perpendicular to the Z axis, and 0 as the center of the quiet zone; S2. Select the calibration system configuration according to the type of compressed field being calibrated, connect the system using a stable phase cable, and preheat the system. S3. Adjust the scanning frame relative to the incoming wave attitude so that the scanning stroke is perpendicular to the direction of the incoming wave. The central control system officially calibrates the data acquisition and completes the calculation of the static field amplitude unevenness, static field phase unevenness, and static field cross-polarization. S4. Set the frequency to be calibrated, and record the logarithmic value of the field strength amplitude and the linear value of the field strength phase at the corresponding calibration position when the scanning frame is in the first posture state. S5. Change the frequency point to be calibrated, repeat step S4, and obtain the amplitude and phase test data of all calibrated frequencies within the working frequency range of the compressed field feed in the first posture state of the scanning frame. S6. Change the second scanning posture and repeat steps S4~S5 to obtain the amplitude and phase test data of all calibrated frequencies within the working frequency range of the compressed field feed source under the second scanning posture state. S7. Change the polarization of the feed antenna and the receiving antenna, and repeat steps S4 to S6. S8. Replace the feed source with another frequency band and repeat steps S4~S7; S9. Change the position of the calibration section and repeat steps S3 to S8 until all principal polarization calibration states are completed. The calibration system includes: a microwave amplitude and phase unit, a scanning equipment unit, and a central control unit; A microwave amplitude and phase unit is used to receive signals and measure the amplitude and phase of the signals; The scanning device unit is used to control the receiving position and orientation of the detection probe; The central control unit is used to remotely control the microwave amplitude and phase unit and the scanning equipment unit, analyze amplitude and phase data in real time, and automatically calculate the quiet zone characteristics. The central control unit is used to acquire the scanning data of the microwave amplitude and phase unit, perform quadratic term fitting of the data curve using the least squares method, and calculate the limit curve by combining the upper limit of amplitude change and the upper limit of phase change. Then, it performs calculations of the amplitude unevenness, phase unevenness, and cross polarization of the static field according to the definitions of flatness, taper, and ripple. The central control unit is also used to encapsulate the control algorithm of the microwave amplitude and phase system, so that the control algorithms corresponding to different instrument models can be interchanged, thereby encapsulating the impact caused by changes in instrument models. Step S3 further includes setting the system operating frequency to the highest operating frequency of the compressed field being calibrated; setting microwave amplitude and phase system parameters, including transmit power, intermediate frequency bandwidth and measurement channel parameters, and controlling the polarization of the feed and receiving antenna to be consistent; The test time and test compensation parameters are set according to the frequency being calibrated. The corresponding data curves are plotted using the data obtained from the calibration system. The scanning frame is controlled to make corresponding attitude adjustments according to the amplitude and phase distribution trends, so that the scanning stroke is perpendicular to the direction of the incoming wave. After the adjustment is in place, the central control system begins to formally calibrate and collect data, and completes the calculation of the amplitude unevenness, phase unevenness, and cross-polarization of the quiet field.

2. The automated calibration system for the amplitude and phase characteristics of plane waves in the static region of a compressed field according to claim 1, characterized in that, The central control unit includes a main control computer, which includes a remote control module and a data processing module. The scanning equipment unit includes a scanning frame and a control chassis. The control chassis provides an external interface for exchanging scanning position parameters, polarization adjustment, position information, and test data.

3. The automated calibration system for the amplitude and phase characteristics of plane waves in the static region of a compressed field according to claim 1, characterized in that, The calibration range is 0.5 GHz to 110 GHz.

4. The automated calibration system for the amplitude and phase characteristics of plane waves in the static region of a compressed field according to claim 3, characterized in that, For close-range testing in the 0.5 GHz to 40 GHz band, the microwave amplitude and phase system includes a signal source, a vector network analyzer, and a receiving antenna.

5. The automated calibration system for the amplitude and phase characteristics of plane waves in the static region of a compressed field according to claim 3, characterized in that, For long-distance testing in the 0.5 GHz to 40 GHz band, the microwave amplitude and phase system includes a signal source, a power amplifier, a vector network analyzer, a low-noise amplifier, and a receiving antenna.

6. The automated calibration system for the amplitude and phase characteristics of plane waves in the static region of a compressed field according to claim 3, characterized in that, For tests with calibration frequencies higher than 40 GHz, connect a low-noise amplifier to the signal receiver and a power amplifier to the signal transmitter.

7. The automated calibration system for the amplitude and phase characteristics of plane waves in the static region of a compressed field according to claim 2, characterized in that, The remote control module is used to control the selection of the rotating shaft, the start and end positions of the movement, the running speed, and the running status indication of the scanning device unit.

8. The automated calibration system for the amplitude and phase characteristics of plane waves in the static region of a compressed field according to claim 2, characterized in that, The remote control module is used to set the instrument parameters of the signal source and vector network analyzer in the microwave amplitude and phase unit. The parameters include scan type, measurement mode, test frequency, scan time and number of points.

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