Multi-wavelength phase calibration method for X-digital phased array antenna

Abstract

The present invention provides a multi-wavelength phase calibration method for an X-ray digital transmission phased array antenna. The calibration method is implemented by a calibration device, which includes a digital transmission phased array antenna to be measured, an L-shaped tooling, a waveguide probe and a counterweight. The digital transmission phased array antenna to be measured and the counterweight are both installed on the L-shaped tooling, and a waveguide probe is arranged directly opposite the L-shaped tooling. Beneficial effects of the present invention: Compared with the single-wavelength normal pointing calibration, the present invention uses multi-wavelength simultaneous calibration during calibration, which reduces the calibration error and makes the measurement result more accurate. When collecting data at the same time, the sampling time of the single-wavelength data and the multi-wavelength data is the same. When the array scale is large, the present invention can obtain multi-channel multi-wavelength phases in one test, and the test efficiency is high.

Description

Technical Field

[0001] The invention belongs to the field of active phased array antenna testing, and in particular relates to a multi-wavelength phase calibration method for an X-digital transmission phased array antenna. Background Art

[0002] With the development of modern test methods and equipment, antenna test technology has made great progress. At present, the main test methods are far-field test, compact field test, and planar near-field test. Antenna far-field test technology is the first to appear and mature. In the actual test process, the test field should be large enough to eliminate the influence of wavefront curvature on test accuracy. Due to the increasingly harsh electromagnetic environment, the increase in the electrical size of the antenna aperture and the requirement for confidentiality of research work, people use near-field test instead of far-field test. Antenna planar near-field test uses a probe with known characteristics to sample the field close to the antenna surface to obtain the amplitude and phase distribution on the antenna aperture, and then converts the near-field data into far-field through FFT conversion. The whole process of near-field test is carried out in a microwave darkroom. The reflection level, multipath interference and electromagnetic environment interference in the test environment are suppressed. Near-field test is not affected by external weather and can work all day and night, shortening the test cycle. Compact field test simulates a field of infinite length with the help of plane waves generated by antennas such as reflectors and horns.

[0003] The antenna planar near-field test uses a probe with known characteristics to scan on a plane several wavelengths (3-10λ) away from the antenna to be tested, measure the amplitude and phase distribution of the antenna at discrete points on the plane, and determine the radiation characteristics of the far-field region of the antenna to be tested through strict mathematical transformation. The antenna near-field test system has the function of testing and calibrating each channel, the function of collecting the detection data of the transmission and reception status from the amplitude and phase monitoring component, and the function of batch calculation and processing of multi-wavelength plane near-field test data. The test data of multi-channel and multi-wavelength can be obtained through a near-field test. Since the probes of the near-field measurement system are all linearly polarized waveguide antennas, the accuracy is high when calibrating the linear polarization antenna array or circular polarization array with the same unit arrangement direction. However, the current multi-wavelength phase calibration of the or circular polarization array has the problem that the value of the multi-channel wavelength cannot be obtained at one time, the test efficiency is low, and the calibration error is large when calibrating multiple wavelengths. After synthesizing the far-field radiation pattern, the radiation pattern performance of each wavelength of the antenna is poor. Summary of the invention

[0004] In view of this, the present invention aims to propose a multi-wavelength phase calibration method for an X-digital transmission phased array antenna to solve at least one problem existing in the above-mentioned prior art.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] A multi-wave phase calibration method for an X-ray digital transmission phased array antenna, the calibration method is implemented by a calibration device, the calibration device comprises a digital transmission phased array antenna to be measured, an L-shaped tooling, a waveguide probe and a counterweight, the digital transmission phased array antenna to be measured and the counterweight are both installed on the L-shaped tooling, and a waveguide probe is arranged directly opposite the L-shaped tooling;

[0007] The calibration method includes the following steps:

[0008] S1. Install the digital transmission phased array antenna to be tested on the L-shaped fixture, and then place it on the platform in the darkroom. Adjust the fixture so that the aperture of the digital transmission phased array antenna to be tested is parallel to the aperture of the waveguide probe. Connect the digital transmission phased array antenna to be tested and the vector network with a radio frequency cable, and connect the host computer and the darkroom operation computer with a control cable.

[0009] S2. Keep the long side of the waveguide probe parallel to the ground, and test the vertical polarization amplitude A of each channel and each wave position according to the set scanning step and channel sequence. cz and phase φ cz ;

[0010] S3. Keep the long side of the waveguide probe perpendicular to the ground, and test the horizontal polarization amplitude A of each channel and each wave position according to the set scanning step and channel sequence. sp and phase φ sp ;

[0011] S4. The vertical polarization amplitude A of each channel and each wave position is obtained. cz and phase φ cz and horizontal polarization amplitude A sp and phase φ sp , converted to complex form, the formula is as follows:

[0012] , , where E cz Represents the vertical electric field, E sp represents the horizontal electric field, i represents an imaginary number, and i 2 =-1;

[0013] S5, using Euler's formula, replace E in step S4 cz and E sp Convert to trigonometric function relationship and calculate E 合 =E cz +E sp , so

[0014] E 合 =A cz ×(cos(φ cz )+i×sin(φ cz ))+A sp ×(cos(φ sp)+i×sin(φ sp ))

[0015] =A cz ×cos(φ cz )+A sp ×cos(φ sp )+i×(A cz ×sin(φ cz )+A sp ×sin(φ sp ));

[0016] φ 合 =arctan((A cz ×sin(φ cz )+A sp ×sin(φ sp )) / (A cz ×cos(φ cz )+A sp ×cos(φ sp )));

[0017] S6. According to the unit arrangement and unit spacing, the phase value of each unit at each wave position is calculated, and the minimum value among the phase values ​​of each channel at each wave position is found. This minimum value is used as the minuend, and the phase value of each channel at each wave position is subtracted from this minimum value to obtain the normalized phase value φ. 归 ;

[0018] S7. Calculate the difference between the two Δφ=φ 合 -φ 归 , calculate the Δφ of each channel at each wave position, find the minimum value, and use this minimum value as the minuend, subtract this minimum value from the phase value of each channel at each wave position, so as to obtain the normalized phase value Δφ 归 ;

[0019] S8, the obtained Δφ 归 , input into the phased array antenna to be tested, repeat steps S2 to S7, and get Δφ 归 , compare the two Δφ 归 If the difference is ≤1, the calibration is completed.

[0020] Furthermore, in step S1, the material of the L-shaped tooling is aluminum alloy.

[0021] Further, in step S2 and step S3, the data transmission phased array antenna and waveguide probe to be tested are both set to 4 times of the wavelength in the distance calibration mode and the test pattern mode.

[0022] Furthermore, in step S2 and step S3, the set scanning step and scanning order are calculated according to the arrangement of antenna elements and the distance from center to center of the elements, and the channel where the upper left corner element of the phased array antenna aperture to be measured is located is defined as channel 1.

[0023] Further, in step S4, the vertical polarization amplitude and phase, horizontal polarization amplitude and phase measured in each channel and each wave position obtained in the test in step S2 and step S3 are converted into complex form by the formula, and the formula expression is E=A×e iφ , where E represents the electric field, A represents the measured amplitude, and φ represents the measured phase.

[0024] Further, in step S5, the two complex expressions in step S4 are converted into trigonometric function relations by Euler's formula, real numbers are added to real numbers, complex numbers are added to complex numbers, and the formula φ is used. 合 =arctan((A cz ×sin(φ cz )+A sp ×sin(φ sp )) / (A cz ×cos(φ cz )+A sp ×cos(φ sp )))Calculate the circular polarization phase.

[0025] Further, in step S6, the phase value of each unit at each wave position is calculated according to the unit arrangement and the unit spacing, which is calculated by the following formula: φ=-360×(sin(theta)×cos(phi)×XLocation+sin(theta)×sin(phi)×YLocation) / lambda, wherein theta represents the off-axis angle, phi represents the rotation angle, XLocation represents the X-axis coordinate of the unit, YLocation represents the Y-axis coordinate of the unit, and lambda represents the wavelength of the corresponding frequency;

[0026] The phase value of each channel at each wave position is calculated, and the minimum value is found. This minimum value is used as the minuend, and the phase value of each channel at each wave position is subtracted from this minimum value to obtain the normalized phase value φ 归 .

[0027] Compared with the prior art, the multi-wavelength phase calibration method of the X-digital transmission phased array antenna described in the present invention has the following advantages:

[0028] (1) Compared with the single-wavelength normal pointing calibration, the multi-wavelength phase calibration method of the X-ray digital transmission phased array antenna described in the present invention adopts multi-wavelength simultaneous calibration during calibration, which reduces the calibration error and makes the measurement result more accurate. When collecting data at the same time, the sampling time of the single-wavelength data and the multi-wavelength data is the same. When the array scale is large, the present invention can obtain multi-channel multi-wavelength phases in one test, and the test efficiency is high.

[0029] (2) The X-ray digital transmission phased array antenna multi-wave phase calibration method described in the present invention obtains data and calculates it in the form of a matrix through Matlab, which reduces the time of manual calculation and ensures the accuracy.

[0030] (3) Compared with the original single-line polarization calibration, the multi-wavelength phase calibration method of the X-digital transmission phased array antenna described in the present invention adopts a circular polarization form of synthesizing two polarizations, vertical polarization and horizontal polarization, which is closer to the actual circular polarization characteristics of the unit. Therefore, the calibration error is lower, and the synthesis performance of the active phased array can be improved. It is reflected in the far-field radiation pattern that the synthesized circular polarization performance is better and the axis ratio is lower. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 A schematic diagram of the distribution of antenna units according to an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of placing the antenna to be tested and the waveguide probe in the near-field test chamber according to an embodiment of the present invention;

[0034] Figure 3 The figure is a flow chart of a calibration method according to an embodiment of the present invention.

[0035] Description of reference numerals:

[0036] 1. Phased array antenna for data transmission to be tested; 2. L-shaped tooling; 3. Waveguide probe; 4. Counterweight. DETAILED DESCRIPTION

[0037] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0040] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0041] like Figures 1 to 3 As shown, a multi-wave phase calibration method for an X-shaped digital transmission phased array antenna is implemented by a calibration device, which includes a digital transmission phased array antenna 1 to be measured, an L-shaped fixture 2, a waveguide probe 3 and a counterweight 4. The digital transmission phased array antenna 1 to be measured and the counterweight 4 are both installed on the L-shaped fixture 2, and a waveguide probe 3 is provided on one side of the L-shaped fixture 2. The calibration method includes the following steps:

[0042] S1. Install the digital transmission phased array antenna 1 to be tested on the L-shaped fixture 2, and then place it on the platform in the darkroom. Adjust the fixture so that the antenna surface is parallel to the waveguide probe 3 surface. Connect the antenna and the vector network with the relevant RF cable, and connect the host computer and the darkroom operation computer with the control cable.

[0043] S2. Keep the long side of the waveguide probe 3 parallel to the ground, and test the vertical polarization amplitude A of each channel and each wave position according to the given scanning step and channel sequence. cz and phase φ cz .

[0044] S3. Keep the long side of waveguide probe 3 perpendicular to the ground, and test the horizontal polarization amplitude A of each channel and each wave position according to the given scanning step and channel sequence. sp and phase φ sp .

[0045] S4. The vertical polarization amplitude A of each channel and each wave position is obtained cz and phase φ cz and horizontal polarization amplitude A sp and phase φ sp , converted to complex form, the formula is as follows:

[0046] , , where E cz Represents the vertical electric field, E sp represents the horizontal electric field, i represents an imaginary number, and i 2 =-1;

[0047] S5. Use Euler's formula to replace E in step S4 cz and E sp Convert to trigonometric function relationship and calculate E 合 =E cz +E sp , so

[0048] E 合 =A cz ×(cos(φ cz )+i×sin(φ cz ))+A sp ×(cos(φ sp )+i×sin(φ sp ))

[0049] =A cz ×cos(φ cz )+A sp ×cos(φ sp )+i×(A cz ×sin(φ cz )+A sp ×sin(φ sp ));

[0050] φ 合 =arctan((A cz ×sin(φ cz )+A sp ×sin(φ sp )) / (A cz ×cos(φ cz )+A sp ×cos(φ sp )));

[0051] S6. According to the unit arrangement and unit spacing, calculate the phase value of each unit at each wave position, find the minimum value among the phase values ​​of each channel at each wave position, and use this minimum value as the minuend, subtract this minimum value from the phase value of each channel at each wave position, so as to obtain the normalized phase value φ 归 .

[0052] S7. Calculate the difference between the two Δφ=φ 合 -φ 归 , calculate the Δφ of each channel at each wave position, find the minimum value among them, and use this minimum value as the minuend, subtract this minimum value from the phase value of each channel at each wave position, so as to obtain the normalized phase value Δφ 归 .

[0053] S8. The obtained Δφ 归 , input into the phased array antenna to be tested, repeat steps S2-S7, and get Δφ 归 , compare the two Δφ 归 If the difference is ≤1, the calibration is completed.

[0054] In a preferred embodiment of the present invention, in step S1, the data transmission phased array antenna 1 to be measured is installed on an L-shaped tooling 2. The L-shaped tooling 2 is designed to be L-shaped and made of aluminum alloy, which is convenient for installing the data transmission phased array antenna 1 to be measured and placing the counterweight 4. The position of the L-shaped tooling 2 is adjusted to keep it level with the waveguide probe 3.

[0055] The L-shaped tooling 2 has a counterweight 4 at the back to keep the phased array antenna 1 to be tested stable. When other antennas to be tested are replaced, the position can be fixed without readjusting the position, thus saving measurement time.

[0056] In a preferred embodiment of the present invention, in steps S2 and S3, the distance between the phased array antenna 1 to be tested and the waveguide probe 3 in both the calibration mode and the test pattern mode is set to 4 times the wavelength.

[0057] In a preferred embodiment of the present invention, in steps S2 and S3, the given scanning step and scanning order are calculated according to the arrangement of antenna elements and the distance from center to center of the elements. The channel where the element at the upper left corner of the antenna aperture is located is usually defined as channel 1.

[0058] In a preferred embodiment of the present invention, in step 4, the vertical polarization amplitude and phase, horizontal polarization amplitude and phase measured at each wave position of each channel obtained in the test of step 2 and step 3 are converted into complex form by a formula, and the formula expression is E=A×e iφ , A represents the measured amplitude, and φ represents the measured phase.

[0059] In a preferred embodiment of the present invention, in step 5, the two complex expressions in step 4 are converted into trigonometric function relationships by Euler's formula, real numbers are added to real numbers, complex numbers are added to complex numbers, and the formula φ is used to convert the two complex expressions in step 4 into trigonometric function relationships by Euler's formula. 合 =arctan((A cz ×sin(φ cz )+A sp ×sin(φ sp )) / (A cz ×cos(φ cz )+A sp ×cos(φ sp )))Calculate the circular polarization phase.

[0060] In a preferred embodiment of the present invention, in step 6, the phase value of each unit at each wave position is calculated according to the unit arrangement mode and the unit spacing, and is calculated by the following formula φ=-360×(sin(theta)×cos(phi)×XLocation+sin(theta)×sin(phi)×YLocation) / lambda, where theta represents the off-axis angle, phi represents the rotation angle, XLocation represents the X-axis coordinate of the unit, YLocation represents the Y-axis coordinate of the unit, and lambda represents the wavelength of the corresponding frequency;

[0061] The phase values ​​of each channel at each wave position are calculated, and the minimum value among them is found. This minimum value is used as the minuend, and the phase value of each channel at each wave position is subtracted from this minimum value to obtain the normalized phase value φ 归 .

[0062] The present invention has the following advantages:

[0063] Compared with the single-wavelength normal pointing calibration, the present invention adopts multi-wavelength simultaneous calibration during calibration, which reduces the calibration error and makes the measurement result more accurate. When collecting data at the same time, the sampling time of single-wavelength data and multi-wavelength data is the same. When the array scale is large, the present invention can obtain multi-channel multi-wavelength phases in one test, and the test efficiency is high.

[0064] The data is obtained and calculated in the form of a matrix using Matlab, which reduces the time of manual calculation while ensuring the accuracy.

[0065] Compared with the original single-line polarization calibration, the use of vertical polarization and horizontal polarization to synthesize circular polarization is closer to the actual circular polarization characteristics of the unit, so the calibration error is lower, which can improve the synthesis performance of the active phased array, which is reflected in the far-field radiation pattern as the synthesized circular polarization performance is better and the axis is lower.

[0066] The present invention is designed for fast multi-channel multi-wavelength phase calibration of circularly polarized antennas, and provides a method for multi-wavelength calibration of digital transmission active phased array circularly polarized antennas. The vertical component and horizontal component of each channel and each wavelength of the digital transmission phased array antenna to be measured are respectively measured using a waveguide probe, converted into a complex form through a mathematical formula, and the vertical component and the horizontal component are added to extract the added circular polarization phase; the theoretical phase of each channel and each wavelength is calculated according to the unit distribution coordinates and the direction of each wavelength, forming a matrix of j rows and k columns; the difference is calculated by comparing the test value with the theoretical value, and the difference is injected into the active phased array antenna until the difference reaches the required requirement. The present invention can obtain the value of multi-channel wavelength in one test, has high test efficiency, calibrates multiple wavelengths at the same time, has a small calibration error, and after synthesizing the far-field directional pattern, the directional pattern performance of each wavelength of the antenna will be better.

[0067] Example 1

[0068] according to Figure 2 , Figure 3 A method for calibrating multiple wave positions of a digital transmission active phased array circularly polarized antenna comprises the following steps:

[0069] 1. Install the data transmission phased array antenna 1 to be tested on the L-shaped fixture 2, and ensure that the antenna (i.e. the data transmission phased array antenna 1 to be tested) is parallel to the fixing surface of the L-shaped fixture 2. The design of the L-shaped fixture 2 should ensure that the antenna remains stable during the test.

[0070] 2. Place the installed L-shaped fixture 2 and antenna on the platform in the darkroom, and adjust the position and angle of the L-shaped fixture 2 to make the antenna aperture parallel to the aperture of the waveguide probe 3. In this step, use precise measuring tools to ensure the parallelism between the antenna aperture and the aperture of the waveguide probe 3.

[0071] Connect the antenna to the RF cable of the vector network analyzer to test the RF performance of the antenna. At the same time, connect the control cable to connect the host computer to the darkroom operation computer for remote control and data acquisition.

[0072] 3. Keep the long side of the waveguide probe 3 parallel to the ground to ensure that the probe remains stable during the test. Figure 1 Antenna layout method, calculate the coordinates of each unit, and then test the vertical polarization amplitude A of each channel and each wave position according to the channel sequence and scanning step cz and phase φ cz , import the measured data into Matlab to form two array matrices with j rows and k columns, where j is the number of channels and K is the number of wave bits, one is the amplitude matrix and the other is the phase matrix.

[0073] 4. Keep the long side of the waveguide probe 3 perpendicular to the ground to ensure that the probe remains stable during the test. Figure 1 Antenna layout method, calculate the coordinates of each unit, and then test the horizontal polarization amplitude A of each channel and each wave position according to the channel sequence and scanning step cz and phase φ cz , import the measured data into Matlab, and also form two array matrices with j rows and k columns, where j is the number of channels and K is the number of wave bits, one is the amplitude matrix and the other is the phase matrix.

[0074] 5. Convert the vertical polarization amplitude Acz matrix and phase φcz matrix, as well as the horizontal polarization amplitude Asp matrix and phase φsp matrix obtained in steps S2 and S3, into complex form. The specific formula is:

[0075] , , where E cz Represents the vertical electric field, E sp represents the horizontal electric field, i represents an imaginary number, and i 2 =-1.

[0076] 6. Calculate the composite electric field. Use Euler's formula to convert Ecz and Esp into trigonometric function relationships and calculate the composite electric field Etotal. The specific formula is:

[0077] E 合 =E cz +E sp

[0078] =A cz ×(cos(φcz)+i×sin(φcz))+A sp ×(cos(φsp)+i×sin(φsp))

[0079] =A cz ×cos(φcz)+A sp ×cos(φsp)+i×(A cz ×sin(φcz)+A sp ×sin(φsp));

[0080] Calculate the phase φ of the resultant electric field 合 , the formula is:

[0081] φ 合 =arctan((A cz ×sin(φcz)+A sp ×sin(φsp)) / (A cz ×cos(φcz)+A sp ×cos(φsp)));

[0082] 7. Through steps 5 and 6, the synthesized circularly polarized electric field phase can be obtained, and the phase is an array matrix with j rows and k columns.

[0083] 8. According to the unit arrangement and unit spacing, the phase value of each unit at each wave position is calculated by the following formula:

[0084] φ=-360×(sin(theta)×cos(phi)×XLocation+sin(theta)×sin(phi)×YLocation) / lambda;

[0085] theta represents the off-axis angle, phi represents the rotation angle, XLocation represents the unit X-axis coordinate, YLocation represents the unit Y-axis coordinate, and lambda represents the wavelength of the corresponding frequency.

[0086] For the convenience of calculation, the phase values ​​of each channel at each wave position are calculated, the minimum value among them is found, and this minimum value is used as the minuend, and the phase value of each channel at each wave position is subtracted from this minimum value to obtain the normalized phase value φ 归 .

[0087] 9. φ obtained from steps 6 and 8 合 and φ 归 , calculate the difference between the two Δφ=φ 合 -φ 归 , calculate the Δφ of each channel at each wave position, find the minimum value among them, and use this minimum value as the minuend, subtract this minimum value from the phase value of each channel at each wave position, so as to obtain the normalized phase value Δφ 归 According to the number of phase shifters, the shift code ΔM is obtained by following step 10. jk , input the shift code into the digital transmission phased array antenna to be tested, and then repeat steps 2-9 until ΔM jk ≤1, calibration is completed.

[0088] 10. According to the number of bits of the digital phase shifter, the phase shifter is selected as 8 bits, and the calculation formula for converting the phase value into the shift code is:

[0089] M=φ / 180 / 2 8 ;

[0090] Then the shift code is rounded without retaining the decimal places.

[0091] The data matrix of the circular polarization phase synthesized from the vertical polarization component and the horizontal polarization component of the present invention is shown in Table 1 below.

[0092] Table 1

[0093] .

[0094] 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, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A multi-wave phase calibration method for X-digital phased array antenna, characterized in that: The calibration method is implemented by a calibration device, which includes a phased array antenna for data transmission and measurement to be measured, an L-shaped tooling, a waveguide probe and a counterweight. The phased array antenna for data transmission and measurement to be measured and the counterweight are both installed on the L-shaped tooling, and a waveguide probe is arranged directly opposite the L-shaped tooling; The calibration method includes the following steps: S1. Install the digital transmission phased array antenna to be tested on the L-shaped fixture, and then place it on the platform in the darkroom. Adjust the fixture so that the aperture of the digital transmission phased array antenna to be tested is parallel to the aperture of the waveguide probe. Connect the digital transmission phased array antenna to be tested and the vector network with a radio frequency cable, and connect the host computer and the darkroom operation computer with a control cable. S2. Keep the long side of the waveguide probe parallel to the ground, and test the vertical polarization amplitude A of each channel and each wave position according to the set scanning step and channel sequence. cz and phase φ cz ; S3. Keep the long side of the waveguide probe perpendicular to the ground, and test the horizontal polarization amplitude A of each channel and each wave position according to the set scanning step and channel sequence. sp and phase φ sp ; S4. The vertical polarization amplitude A of each channel and each wave position is obtained. cz and phase φ cz and horizontal polarization amplitude A sp and phase φ sp , converted to complex form, the formula is as follows: Among them, E cz Represents the vertical electric field, E sp represents the horizontal electric field, i represents an imaginary number, and i 2 = -1; S5, using Euler's formula, replace E in step S4 cz and E sp Convert to trigonometric function relationship and calculate E 合 =E cz +E sp , so E 合 =A cz ×(cos(φ cz )+i×sin(φ cz ))+A sp ×(cos(φ sp )+i×sin(φ sp )) =A cz ×cos(φ cz )+A sp ×cos(φ sp )+i×(A cz ×sin(φ cz )+A sp ×sin(φ sp )); f 合 =arctan((A cz ×sin(φ cz )+A sp ×sin(φ sp )) / (A cz ×cos(φ cz )+A sp ×cos(φ sp ))); S6. According to the unit arrangement and unit spacing, the phase value of each unit at each wave position is calculated, and the minimum value among the phase values ​​of each channel at each wave position is found. This minimum value is used as the minuend, and the phase value of each channel at each wave position is subtracted from this minimum value to obtain the normalized phase value φ. 归 ; In step S6, the phase value of each unit at each wave position is calculated according to the unit arrangement and unit spacing, which is calculated by the following formula: φ = -360 × (sin (theta) × cos (phi) × XLocation+sin(theta)×sin(phi)×YLocation) / lambda, where theta represents the off-axis angle, phi represents the rotation angle, XLocation represents the unit X-axis coordinate, YLocation represents the unit Y-axis coordinate, and lambda represents the wavelength of the corresponding frequency; The phase value of each channel at each wave position is calculated, and the minimum value is found. This minimum value is used as the minuend, and the phase value of each channel at each wave position is subtracted from this minimum value to obtain the normalized phase value φ 归 ; S7, calculate the difference between the two Δφ=φ 合 -φ 归 , calculate the Δφ of each channel at each wave position, find the minimum value, and use this minimum value as the minuend, subtract this minimum value from the phase value of each channel at each wave position, so as to obtain the normalized phase value Δφ 归 ; S8, the obtained Δφ 归 , input into the phased array antenna to be tested, repeat steps S2 to S7, and get Δφ 归 , compare the two Δφ 归 If the difference is ≤1, the calibration is completed.

2. The multi-wavelength phase calibration method of X-ray digital transmission phased array antenna according to claim 1, characterized in that: In step S1, the material of the L-shaped tooling is aluminum alloy.

3. The multi-wavelength phase calibration method of X-ray digital transmission phased array antenna according to claim 1, characterized in that: In step S2 and step S3, the data transmission phased array antenna and waveguide probe to be tested are both set to 4 times of the wavelength in the distance calibration mode and the test pattern mode.

4. The multi-wavelength phase calibration method of X-ray digital transmission phased array antenna according to claim 1, characterized in that: In step S2 and step S3, the set scanning step and scanning order are calculated according to the antenna array element arrangement and the distance from center to center of the array element, and the channel where the array element at the upper left corner of the aperture of the phased array antenna to be measured is located is defined as channel 1.

5. The multi-wavelength phase calibration method of X-ray digital transmission phased array antenna according to claim 1, characterized in that: In step S4, the vertical polarization amplitude and phase, horizontal polarization amplitude and phase measured in each channel and each wave position obtained in the test in step S2 and step S3 are converted into complex form by the formula, and the formula expression is E=A×e iφ , where E represents the electric field, A represents the measured amplitude, and φ represents the measured phase.

6. The multi-wavelength phase calibration method of X-ray digital transmission phased array antenna according to claim 1, characterized in that: In step S5, the two complex expressions in step S4 are converted into trigonometric function relations by Euler's formula, real numbers are added to real numbers, complex numbers are added to complex numbers, and the formula φ is used to convert the two complex expressions into trigonometric function relations. 合 =arctan((A cz ×sin(φ cz )+A sp ×sin(φ sp )) / (A cz ×cos(φ cz )+A sp ×cos(φ sp )))Calculate the circular polarization phase.

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