Waveguide probe structure, and calibration device and calibration method of antenna array

Abstract

The invention provides a waveguide probe structure, and a calibration device and a calibration method of an antenna array, and belongs to the technical field of antennas. The waveguide probe structure comprises a waveguide coaxial converter, a tapered waveguide and a first straight waveguide, wherein the waveguide coaxial converter is configured to transmit and receive two orthogonal linear polarization signals; the tapered waveguide is provided with a first waveguide cavity, and the first waveguide cavity is provided with a first waveguide port and a second waveguide port which are arranged along the length direction of the first waveguide cavity; the first waveguide port is connected with the waveguide coaxial converter, and the second waveguide port is connected with the first straight waveguide; the size of the cross section of the first waveguide cavity is monotonically increased in the direction from the first waveguide port to the second waveguide port; the first straight waveguide is provided with a second waveguide cavity, and the size of the cross section of the second waveguide cavity is equal to the size of the second waveguide port.

Description

Waveguide probe structure, antenna array calibration device and calibration method Technical Field

[0001] The present disclosure belongs to the field of antenna technology, and particularly relates to a waveguide probe structure, an antenna array calibration device, and a calibration method. Background Art

[0002] Adjustable reflectarray antennas typically implement beamforming and beam scanning based on the voltage-absolute phase response curve of the reflector element. Due to processing errors during the manufacturing process of the reflector elements, it is difficult to ensure the consistency of the individual reflector elements in the reflectarray antenna. For example, the initial phase and phase shift range of each reflector element vary significantly, meaning that the voltage-absolute phase response curve of each reflector element is different. If the reflectarray is phase-matched based on the voltage-absolute phase response curve of the reflector element, it will cause phase matching errors, resulting in the beam pointing not being able to scan as expected, such as beam deformation, gain reduction, or even the inability to reconstruct the beam.

[0003] Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art and provides a waveguide probe structure, an antenna array calibration device and a calibration method.

[0005] In a first aspect, an embodiment of the present disclosure provides a waveguide probe structure, which includes a waveguide-to-coaxial converter, a gradient waveguide, and a first straight waveguide; wherein,

[0006] The waveguide-to-coaxial converter is configured to transmit and receive two orthogonal linear polarization signals;

[0007] The gradient waveguide has a first waveguide cavity, and the first waveguide cavity has a first waveguide port and a second waveguide port arranged along its length; the first waveguide port is connected to the waveguide coaxial converter, and the second waveguide port is connected to the first straight waveguide; the size of the cross section of the first waveguide cavity increases monotonically in the direction from the first waveguide port to the second waveguide port;

[0008] The first straight waveguide has a second waveguide cavity, and the size of the cross section of the second waveguide cavity is equal to the size of the second waveguide port.

[0009] Wherein, the waveguide-to-coaxial converter comprises a second straight waveguide, a first feeding port, a second feeding port and an isolation component;

[0010] The feeding directions of the first feeding port and the second feeding port are orthogonal; the second straight waveguide has a third waveguide cavity, and the first feeding port, the second feeding port and the isolation component are all installed on the side wall of the second straight waveguide and extend into the third waveguide cavity; the isolation component is located between the first feeding port and the second feeding port and parallel to one of them.

[0011] The waveguide probe structure further includes a first fixing component, which is mounted on a side wall of the second straight waveguide and has a plurality of mounting holes.

[0012] Wherein, the first fixing component includes a flange.

[0013] Wherein, the waveguide-to-coaxial converter and the gradient waveguide are fixedly connected via a second fixing component.

[0014] Wherein, the second fixing component includes a flange.

[0015] Wherein, the opening angle of the gradient waveguide is 1.5° to 2.5°.

[0016] Wherein, the waveguide probe structure further includes a gasket, and the gasket is fixed on the end face of the first straight waveguide facing away from the gradient waveguide.

[0017] The length of the first straight waveguide is greater than the wavelength corresponding to the cutoff frequency of the transmitted microwave signal.

[0018] In a second aspect, an embodiment of the present disclosure provides a calibration device for an antenna array, which includes a waveguide probe structure, a vector network analyzer, and a controller; wherein the waveguide probe structure adopts any of the waveguide probe structures described above;

[0019] The vector network analyzer is configured to transmit a microwave signal through the waveguide probe structure to an in-array unit to be calibrated, receive a microwave signal reflected by the in-array unit and transmitted through the waveguide probe structure, and analyze the received microwave signal to obtain network parameters of the in-array unit based on a relationship between incident microwaves and reflected microwaves.

[0020] The controller is configured to analyze the vector network analyzer to obtain the network parameters of the array unit based on the relationship between the incident microwave and the reflected microwave, and obtain the calibration error through a preset algorithm.

[0021] In a third aspect, an embodiment of the present disclosure provides a calibration method for an antenna array, the method employing the calibration device described above; the antenna array includes M×N array elements, where one of M and N is a positive integer greater than or equal to 1, and the other is a positive integer greater than or equal to 2; the method comprising: calibrating the M×N array elements sequentially based on a pre-acquired reference phase codebook; the reference phase codebook including correspondences between multiple test voltages, reference amplitudes, and reference phases;

[0022] The steps of calibrating the array unit for the i-th row and j-th column include:

[0023] Sequentially loading the test voltages in the reference phase codebook to the array unit in the i-th row and j-th column, and after each loading of the test voltage, transmitting the microwave signal radiated by the array unit in the i-th row and j-th column to a vector network analyzer through a waveguide probe structure, so that the vector network analyzer collects the network parameters of the array unit in the i-th row and j-th column based on the relationship between the incident microwave and the reflected microwave; 0 < i ≤ M, 0 < j ≤ N, i and j are both positive integers;

[0024] Based on the array unit in the i-th row and j-th column, under different test voltages, the network parameters of the waveguide probe structure and the array unit based on the relationship between the incident microwave and the reflected microwave collected by the vector network analyzer, obtaining a first S-parameter matrix;

[0025] The controller processes the first S parameter matrix to obtain a normalized S parameter matrix of the antenna unit in the i-th row and j-th column under each test voltage, and determines a target voltage absolute phase response curve and a target voltage amplitude response curve corresponding to the antenna unit in the i-th row and j-th column; the normalized S parameter matrix is ​​used to characterize the network parameters of the array unit in the i-th row and j-th column under the test voltage based on the relationship between the incident microwave and the reflected microwave.

[0026] The step of processing the first S parameter matrix to obtain a normalized S parameter matrix of the antenna unit in the i-th row and j-th column at each test voltage includes:

[0027] Placing the waveguide probe structure on a reflective component, transmitting the microwave signal reflected by the reflective component to a vector network analyzer through the waveguide probe structure, so that the vector network analyzer analyzes the waveguide probe structure and the reflective component to establish network parameters based on the relationship between the incident microwave and the reflected microwave;

[0028] The vector network analyzer determines the second S-parameter matrix based on the network parameters of the waveguide probe structure and the reflective component based on the relationship between the incident microwave and the reflected microwave;

[0029] The controller obtains a normalized S parameter matrix of the antenna unit in the i-th row and j-th column at each test voltage based on vector subtraction between the first S parameter matrix and the second S parameter matrix.

[0030] Wherein, when the working mode of the antenna array is circular polarization, the step of determining the target voltage absolute phase response curve and the target voltage amplitude response curve corresponding to the antenna unit in the i-th row and j-th column includes:

[0031] The normalized S parameter matrix is ​​transformed into a linear-circular polarization basis to determine a target voltage absolute phase response curve and a target voltage amplitude response curve corresponding to the antenna unit in the i-th row and j-th column.

[0032] The calibration method further includes the step of obtaining a reference phase codebook; the reference phase codebook includes a corresponding relationship response curve between the test voltage and the reference phase of each array unit, and a corresponding relationship response curve between the test voltage and the reference amplitude;

[0033] Acquiring the response curve of the corresponding relationship between the test voltage and the reference phase, and the response curve of the corresponding relationship between the test voltage and the reference amplitude in the array unit in the i-th row and j-th column includes:

[0034] Based on a pre-acquired test voltage set, the test voltages in the test voltage set are sequentially loaded onto the array unit in the i-th row and j-th column; a waveguide probe structure is placed on the array unit in the i-th row and j-th column, and a vector network analyzer obtains network parameters of the array unit in the i-th row and j-th column and the waveguide probe structure based on a relationship between incident microwaves and reflected microwaves through waveguide probe structure analysis, thereby determining a first reference S-parameter matrix; 0 < i ≤ M, 0 < j ≤ N, where i and j are both positive integers;

[0035] Placing a waveguide probe structure on a reflective component, using a vector network analyzer to collect microwave signals reflected by the reflective component through the waveguide probe structure, and analyzing network parameters between the reflective component and the waveguide probe structure based on a relationship between incident microwaves and reflected microwaves to determine a second reference S-parameter matrix;

[0036] The controller obtains a normalized reference S parameter matrix based on the first reference S parameter matrix and the second reference S parameter matrix, and processes the normalized reference S parameter matrix to determine a corresponding relationship response curve between the test voltage and the reference phase in the i-th row and j-th column of the array unit, as well as a corresponding relationship response curve between the test voltage and the reference amplitude.

[0037] Wherein, the material of the reflective component is copper or aluminum. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG1 is a schematic diagram of a waveguide probe structure placed on an antenna array according to an embodiment of the present disclosure.

[0039] FIG. 2 is a top view of a phase shifter in an array according to an embodiment of the present disclosure.

[0040] FIG3 is a cross-sectional view taken along line AA′ in FIG2 .

[0041] FIG4 is a cross-sectional view taken along line BB′ in FIG2 .

[0042] FIG5 is a front view of the waveguide probe structure according to an embodiment of the present disclosure.

[0043] FIG6 is a top view of the waveguide probe structure according to an embodiment of the present disclosure.

[0044] FIG7 is a schematic diagram of a gasket of a waveguide probe structure according to an embodiment of the present disclosure.

[0045] FIG8 is a flowchart of a calibration method for an antenna array according to an embodiment of the present disclosure.

[0046] FIG9 is a flowchart of obtaining a reference phase codebook in the antenna array calibration method according to an embodiment of the present disclosure.

[0047] FIG10 a is a voltage-amplitude response curve of the main polarization (right-hand circular polarization) when the working mode of the antenna array is right-hand circular polarization and the working frequency is 19.725 GHz.

[0048] FIG10 b is a cross-polarization (left-hand circular polarization) voltage-amplitude response curve when the antenna array operates in right-hand circular polarization mode at a frequency of 19.725 GHz.

[0049] FIG11 a is a voltage-absolute phase response curve of the main polarization (right-hand circular polarization) when the working mode of the antenna array is right-hand circular polarization and the working frequency is 19.725 GHz.

[0050] FIG11 b is a cross-polarization (left-hand circular polarization) voltage-absolute phase response curve when the antenna array operates in right-hand circular polarization mode at a frequency of 19.725 GHz.

[0051] FIG12 a shows the amplitude distribution when the antenna array is calibrated to 0° at a working frequency of 19.725 GHz and the working mode of the antenna array is right-hand circular polarization.

[0052] FIG12 b shows the phase distribution when the antenna array is calibrated to 0° at a working frequency of 19.725 GHz and the working mode of the antenna array is right-hand circular polarization.

[0053] FIG13 a shows the amplitude distribution when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz and the antenna array beam angle is 90°.

[0054] FIG13 b shows the phase distribution when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz and the antenna array beam angle is 90°.

[0055] FIG13 c shows the theoretical phase distribution when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz and the antenna array beam angle is 90°.

[0056] Figure 13d shows the phase error distribution when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz and the antenna array beam angle is 90°. DETAILED DESCRIPTION

[0057] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0058] Unless otherwise defined, the technical or scientific terms used in this disclosure should have the usual meanings understood by people with ordinary skills in the field to which this disclosure belongs. The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one", "an" or "the" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0059] Figure 1 is a schematic diagram of a waveguide probe structure placed on an antenna array according to an embodiment of the present disclosure. As shown in Figure 1 , in this embodiment of the present disclosure, the antenna array may include M×N array elements 10, each of which may include p×q array elements 100. One of M and N is a positive integer greater than or equal to 1, and the other is a positive integer greater than or equal to 2. Both p and q are integers greater than or equal to 2. In the following description, p=q=2 is used as an example. However, it should be understood that this does not limit the scope of protection of this embodiment of the present disclosure. The antenna array in this embodiment of the present disclosure is a reflectarray, and each array element 100 may include a phase adjustment unit and a radiating unit. The phase adjustment unit may shift the phase of a received microwave signal and radiate it through the reflective unit. The reflective unit may also receive microwave signals and transmit them to the phase adjustment unit for phase shifting. The reflective unit may include, but is not limited to, a reflective patch. The phase adjustment unit may include, but is not limited to, a phase shifter. In this embodiment of the present disclosure, a differential two-wire phase shifter is used as an example. The adjustable dielectric layer in the phase shifter may include, but is not limited to, a liquid crystal layer. In the embodiment of the present disclosure, the adjustable dielectric layer is taken as a liquid crystal layer as an example.

[0060] Figure 2 is a schematic diagram of a first exemplary phase shifter according to an embodiment of the present disclosure; Figure 3 is a cross-sectional view taken along line AA in Figure 2; and Figure 4 is a cross-sectional view taken along line BB in Figure 2. As shown in Figures 5 and 6, the phase shifter includes a first dielectric substrate 40 and a second dielectric substrate 50 disposed opposite each other, a first main line 21, a second main line 22, a plurality of spaced patch electrodes 23, and a liquid crystal layer 60. The liquid crystal layer 60 is formed between the first dielectric substrate 40 and the second dielectric substrate 50. The first and second main lines 21, 22 extend in the same direction and are both disposed on the side of the first dielectric substrate 40 proximal to the liquid crystal layer 60. A plurality of spaced patch electrodes 23 are arranged side by side along the direction in which the first main line 21 extends, and the patch electrodes 23 are disposed on the side of the second dielectric substrate 50 proximal to the liquid crystal layer 60. The orthographic projections of the two opposing ends of the patch electrodes 23 along their extension direction onto the first dielectric substrate 40 overlap with the orthographic projections of the first and second main lines 21, 22 onto the first dielectric substrate 40, respectively. In this case, the first main line 21 and the second main line 22 respectively form a capacitor area with the overlapping area of ​​the patch electrode 23. By loading different voltages on the first main line 21, the second main line 22 and the patch electrode 23, an electric field is formed in the overlapping area of ​​the first main line 21 and the patch electrode 23, and an electric field is also formed in the overlapping area of ​​the second main line 22 and the patch electrode 23, so that the dielectric constant of the liquid crystal molecules in the overlapping area of ​​the first main line 21 and the patch electrode 23 and the overlapping area of ​​the second main line 22 and the patch electrode 23 changes, thereby realizing phase shift of the microwave signal.

[0061] It should be noted that the phase shifter illustrated in Figures 3 and 4 also includes a reference electrode layer 70. In reality, the operation of the phase shifter does not depend on the reference electrode layer 70. When the phase shifter is integrated into an antenna, one or more reference electrode layers 70 are required. Of course, if the antenna itself has a reference electrode layer 70 integrated into it, the reference electrode layer 70 of the phase shifter can also be shared with the reference electrode layer 70 in the antenna. The reference electrode layer 70 can be disposed on the side of the first dielectric substrate 40 facing away from the liquid crystal layer 60, or on the side of the second dielectric substrate 50 facing away from the liquid crystal layer 60. Furthermore, the reference electrode layer 70 includes, but is not limited to, a ground layer. As long as the reference electrode layer 70 forms a current loop with the first main line 21 and the patch electrode 23, and with the second main line 22 and the patch electrode 23, it is sufficient. For a reflectarray antenna, the reference electrode layer 70 can also serve as a reflector.

[0062] In some examples, the patch electrodes 23 in the phase shifter can be electrically connected via a connecting electrode 24. In this case, when the phase shifter is operating, the same bias voltage can be applied to each patch electrode 23, thereby facilitating control. The orthographic projection of the connecting electrode 24 on the first dielectric substrate 40 does not overlap with the orthographic projections of the first trunk line 21 and the second trunk line 22 on the first dielectric substrate 40.

[0063] In some examples, the patch electrodes 23 in the phase shifter are arranged periodically, for example, with equal spacing between the patch electrodes 23. In some examples, the areas of overlap between the orthographic projections of the first main line 21 on the first dielectric substrate 40 and the patch electrodes 23 are equal; and / or the areas of overlap between the orthographic projections of the second main line 22 on the first dielectric substrate 40 and the patch electrodes 23 are equal. This arrangement facilitates control of the phase shifter. Furthermore, the widths of the patch electrodes 23 can be equal, and the lengths of the patch electrodes 23 can also be equal.

[0064] In some examples, the first and second main lines 21, 22 in the phase shifter can both be straight transmission lines. The first and second main lines 21, 22 can extend parallel to each other. This arrangement facilitates miniaturization of the phase shifter and, in turn, helps achieve a high degree of antenna integration. Of course, the first and second main lines 21, 22 can also be curved, and the shapes of the first and second main lines 21, 22 are not limited in the presently disclosed embodiments.

[0065] The inventors discovered that due to the different thicknesses of liquid crystals during the manufacturing process, the applied voltage decreases as the distance between the driving signal lines increases, resulting in uneven performance of each unit phase shifter in the array.

[0066] In response to the above technical problems, the following technical solutions are provided in the embodiments of the present disclosure.

[0067] FIG5 is a front view of the waveguide probe structure of the embodiment of the present disclosure; FIG6 is a top view of the waveguide probe structure of the embodiment of the present disclosure; FIG7 is a schematic diagram of the gasket 1e of the waveguide probe structure of the embodiment of the present disclosure; As shown in FIG1, 5-7, the embodiment of the present disclosure provides a waveguide probe structure, whose operating frequency is 17-21 GHz, located in the K band (18 to 27 GHz). The waveguide probe structure is mainly used in the calibration method of the adjustable array unit 10 to transmit microwave signals to the adjustable array unit 10 to be measured. The microwave signals transmitted and received by the waveguide probe are then analyzed by a vector network analyzer to obtain network parameters based on the relationship between the incident microwave and the reflected microwave. Finally, the network parameters based on the measured relationship between the incident microwave and the reflected microwave are processed and analyzed by a controller.

[0068] The waveguide probe structure includes a waveguide-to-coaxial converter 1a, a tapered waveguide 1b, and a first straight waveguide 1c. The waveguide-to-coaxial converter 1a is configured to transmit and receive two orthogonal linearly polarized signals. The tapered waveguide 1b has a first waveguide cavity with a first waveguide opening and a second waveguide opening positioned opposite each other along its length. The cross-sectional dimensions of the first waveguide cavity increase monotonically in the direction from the first waveguide opening to the second waveguide opening, i.e., the longitudinal cross-section of the first waveguide cavity is horn-shaped. The first waveguide opening of the first waveguide cavity is connected to the waveguide-to-coaxial converter 1a, and the second waveguide opening of the first waveguide cavity is connected to the first waveguide. The first straight waveguide 1c has a second waveguide cavity, and the cross-sectional dimensions of the second waveguide cavity are equal to those of the second waveguide opening.

[0069] It should be noted that the cross section of the first waveguide cavity refers to the cross section obtained by cutting the first waveguide cavity along the length direction perpendicular to the first waveguide cavity. The waveguide cavities of the waveguide-coaxial converter 1a, the tapered waveguide 1b, and the first straight waveguide 1c are compatible. For example, the cross sections of the waveguide cavities of the waveguide-coaxial converter 1a, the tapered waveguide 1b, and the first straight waveguide 1c are all rectangular or circular. In the embodiment disclosed herein, the cross sections of the waveguide cavities of the waveguide-coaxial converter 1a, the tapered waveguide 1b, and the first straight waveguide 1c are all square. The second waveguide cavity of the first straight waveguide 1c is a rectangular cavity, that is, the cross-sectional dimensions of the second waveguide cavity at each position along its length are the same. When the cross section of the waveguide cavity is square, the equal dimensions of the cross sections of the two refer to the equal length and width of the cross sections of the two; when the cross section of the waveguide cavity is circular, the equal dimensions of the cross sections of the two refer to the equal length and diameter of the cross sections of the two; when the cross section of the waveguide cavity is rectangular, the length of the cross sections of the two refer to the equal length and diameter of the cross sections of the two; and when the cross section of the waveguide cavity is rectangular, the length of the cross sections of the two refer to the double length and width of the cross sections of the two.

[0070] The waveguide probe structure provided in the embodiment of the present disclosure forms a stable main mode working mode by adding a first straight waveguide 1c on the side of the tapered waveguide 1b away from the waveguide-to-coaxial converter 1a.

[0071] In some examples, the waveguide-to-coaxial converter 1a includes a second straight waveguide, a first feeding port 101, a second feeding port 102, and an isolation component 103. The second straight waveguide has a third waveguide cavity, and the third waveguide cavity has a third waveguide port that is compatible with and connected to the first waveguide cavity. The first feeding port 101 and the second feeding port 102 are coaxial structures fed in two orthogonal directions. The first feeding port 101, the second feeding port 102, and the isolation component 103 are all mounted on the side wall of the second straight waveguide away from the third waveguide port and extend into the third waveguide cavity. The isolation component 103 is located between the first feeding port 101 and the second feeding port 102, and is arranged parallel to one of the two. For example, the third straight waveguide includes a first side wall, a second side wall, a third side wall, and a fourth side wall connected in a clockwise direction, the first feeding port 101 is mounted on the first side wall and extends into the third waveguide cavity, and the second feeding port 102 and the isolation component 103 are mounted on the second feeding port 102 and extend into the third waveguide cavity. For example, the first feeding port 101 and the second feeding port 102 both have probes. In this case, the intersection of the extended structure of the probe of the first feeding port 101 and the axis of the third waveguide cavity is the first intersection, the intersection of the extended structure of the probe of the second feeding port 102 and the axis of the third waveguide cavity is the second intersection, and the intersection of the extended structure of the isolation component 103 and the axis of the third waveguide cavity is the third intersection. The third intersection is located between the first intersection and the second intersection, and the second intersection is closer to the third waveguide port than the first intersection. Furthermore, the isolation component 103 traverses the third waveguide cavity, and the coupling between the first feeding port 101 and the second feeding port 102 can be effectively reduced by providing the isolation component 103. The isolation component 103 can be cylindrical and made of an ideal conductive material, such as copper, aluminum or other good metal conductors.

[0072] Furthermore, the length of the first waveguide cavity matches the operating frequency band of 17-21 GHz, which is located in the K band. The side wall of the first straight waveguide 1c is made of a metal material with a certain thickness, for example, the thickness of the side wall of the first waveguide cavity is 4 mm.

[0073] Furthermore, a first fixing assembly 1d is mounted on the sidewall of the second straight waveguide for securing it to an external device, such as a motor or bracket, that controls the position of the waveguide probe structure. For example, mounting holes 104 are provided on the first fixing assembly 1d to facilitate securing it to external equipment. In one example, the first fixing assembly 1d can be a flange, specifically a circular flange, and the mounting holes 104 can be evenly spaced along the circumference of the circular flange.

[0074] Furthermore, the waveguide-to-coaxial converter 1a can be secured to the tapered waveguide 1b via a second securing assembly 1f. Specifically, the second securing assembly 1f can be secured to the sidewall of the tapered waveguide 1b, and then fixedly connected to the first securing assembly 1d. For example, the second securing assembly 1f can be secured to the first securing assembly 1d via screws. In one example, the second securing assembly 1f can be a flange, such as a square flange, which can be secured to the circular flange of the first securing assembly 1d via screws.

[0075] In some examples, the function of the tapered waveguide 1b is to align the third waveguide opening of the second straight waveguide with the boundary of the subarray element to be measured. The longitudinal cross-section of the tapered waveguide 1b is horn-shaped, and the sidewalls of the tapered waveguide 1b are made of metal of a certain thickness. For example, the sidewalls of the tapered waveguide 1b are 4 mm thick. Furthermore, the opening angle of the tapered waveguide 1b is approximately 1.5° to 2.5°, for example, 2°.

[0076] In some examples, the second waveguide cavity of the first straight waveguide 1c has a fourth waveguide port and a fifth waveguide port arranged opposite each other along its length. The second waveguide port of the first waveguide cavity communicates with the fourth waveguide port of the second waveguide cavity, and both are of the same size. When the waveguide probe structure transmits a microwave signal to the on-array unit 10, the fifth waveguide port faces the on-array unit 10, aligns with the edge of the on-array unit 10, and covers the on-array unit 10, thereby measuring the average reflection response characteristics of multiple on-arrays 100 in the array unit 10. For example, when the on-array unit 10 includes 2×2 on-arrays 100, and the fifth waveguide port is square, the inner side length of the fifth waveguide port is equal to the length of two on-arrays 100. When the size of the array unit 10 increases, for example, when a single array unit 10 includes 3×3 arrays 100 or 4×4 arrays 100, to shorten the time required to extract the characteristics of the array unit 10, the size of the corresponding fifth waveguide port is increased compared to a 2×2 array unit 10. This means that the size of the second waveguide port of the tapered waveguide 1b is correspondingly increased. When a single array unit 10 includes 3×3 arrays 100, if the fifth waveguide port is square, the inner side length of the fifth waveguide port is equal to the length of three arrays 100. When a single array unit 10 includes 4×4 arrays 100, if the fifth waveguide port is square, the inner side length of the fifth waveguide port is equal to the length of four arrays 100. In these cases, the sizes of the third waveguide port of the second straight waveguide and the first waveguide port of the tapered waveguide 1b remain unchanged compared to a 2×2 array unit 10.

[0077] Furthermore, the incident angle of the microwave signal corresponding to the main mode working mode in the waveguide can be calculated using the following formula.

[0078]

[0079] Wherein, λ is the wavelength corresponding to the operating frequency, and a is the side length of the fifth waveguide opening of the first straight waveguide 1c.

[0080] Furthermore, the sidewalls of the first straight waveguide 1c are made of metal with a certain thickness, for example, 4 mm. The function of the first straight waveguide 1c is to establish a stable main mode operating mode. The gradient waveguide 1b exhibits discontinuities during microwave signal transmission. To minimize or even eliminate the impact of these discontinuities on the unit reflection response, the length of the first straight waveguide 1c should be greater than the wavelength corresponding to the cutoff frequency, for example, 45 mm.

[0081] In some examples, the waveguide probe structure of the embodiment of the present disclosure not only includes the above-mentioned structure, but also may include a gasket 1e, which is fixed on the end face of the first straight waveguide 1c away from the gradient waveguide 1b. For example: the gasket 1e is fixed to the end face of the first straight waveguide 1c away from the gradient waveguide 1b by a conductive adhesive. It should be noted that the gasket 1e is annular, and its opening corresponds to the waveguide cavity of the first straight waveguide 1c, and the size of the physical part of the gasket 1e is adapted to the thickness of the side wall of the first straight waveguide 1c. In the embodiment of the present disclosure, bonding the gasket 1e to the end face of the first straight waveguide 1c away from the gradient waveguide 1b can effectively avoid scratching the surface of the antenna array when measuring through the waveguide probe structure. In addition, when measuring at different array units 10, it is only necessary to move the waveguide probe structure on the surface of the antenna array, and there is no need to lift the waveguide probe structure.

[0082] Furthermore, the gasket 1e is a conductive elastic gasket 1e with a certain thickness, which can be 1.57 mm. The thickness of the gasket 1e can also be selected according to specific test requirements. The gasket 1e is a conductive elastic body, a waveguide lining, and is made of conductive rubber.

[0083] The present disclosure also provides an antenna array calibration device, which includes a waveguide probe structure, a vector network analyzer, and a controller. The waveguide probe structure may adopt any of the aforementioned structures. The vector network analyzer is configured to transmit a microwave signal through the waveguide probe structure to an array unit 10 to be calibrated, and to receive a microwave signal reflected by the array unit 10 and transmitted via the waveguide probe structure, and to analyze and obtain network parameters of the array unit 10 based on the relationship between the incident microwave and the reflected microwave based on the received microwave signal; and the controller is configured to analyze the network parameters based on the relationship between the incident microwave and the reflected microwave obtained by the vector network analyzer, and to obtain a calibration error through a preset algorithm.

[0084] The present disclosure provides a calibration method for an antenna array, which adopts the calibration device described above. It should be noted that in this calibration method, a waveguide probe structure having two feeding ports connected to a vector network analysis, namely, the first feeding port 101 and the second feeding port 102 described above, is taken as an example. The antenna array calibrated by this calibration method includes M×N array units 10, and each array unit 10 may include p×q array units 100. Wherein, M and N are both 12, and p and q are both 2. That is, the antenna array includes 576 arrays 100, that is, 576 phase shifters.

[0085] The antenna array calibration method of the embodiment of the present disclosure includes: calibrating M×N array elements 10 based on a pre-acquired reference phase codebook. The reference phase codebook includes a plurality of correspondences between test voltages and amplitudes and phases; for example, the reference phase codebook includes a response curve of the correspondence between test voltages and reference phases, and a response curve of the correspondence between test voltages and reference amplitudes. FIG8 is a flow chart of the antenna array calibration method of the embodiment of the present disclosure; as shown in FIG8 , the steps of calibrating the array element 10 in the i-th row and j-th column include:

[0086] S11. Sequentially load the test voltages in the reference phase-matching codebook to the array unit 10 in the i-th row and j-th column. After each test voltage is loaded, transmit the microwave signal reflected by the array unit 10 in the i-th row and j-th column to the vector network analyzer through the waveguide probe structure, so that the vector network analyzer collects the network parameters of the array unit 10 in the i-th row and j-th column based on the relationship between the incident microwave and the reflected microwave; 0<i≤M, 0<j≤N, i and j are both positive integers.

[0087] It should be noted that applying a test voltage to the i-th row, j-th column of the array unit 10 refers to applying a test voltage to each phase shifter in the array 100 of the array unit 10. Specifically, the voltage difference between the first and second electrode layers of the phase shifter is the test voltage. Under different test voltages, the phase shifter's phase shift angle to the microwave signal varies, resulting in different phases and amplitudes.

[0088] In some examples, step S11 may include sequentially loading the test voltages in the reference phase codebook to the array unit 10 in the i-th row and j-th column, and after each test voltage is loaded, the vector network analyzer transmits a microwave signal of a specific frequency band (for example, 17-21 GHz, located in the K band) to the array unit 10 in the i-th row and j-th column through the first feeding port 101 and the second feeding port 102 of the waveguide probe structure, and after phase shifting the microwave signal in the array unit 10 in the i-th row and j-th column, the microwave signal is reflected, and the vector network analyzer collects the phase and amplitude of the phase-shifted microwave signal through the first feeding port 101 and the second feeding port 102 of the waveguide probe structure to obtain network parameters based on the relationship between the incident microwave and the reflected microwave.

[0089] In some examples, the calibration method in the disclosed embodiments may include step S10 of obtaining a phase-matching codebook at a specific beam angle. The reference phase-matching codebook includes a corresponding relationship response curve between the test voltage and reference amplitude at each array element 10, as well as a corresponding relationship response curve between the test voltage and reference phase. The corresponding relationship response curve between the test voltage and reference phase, as well as the corresponding relationship response curve between the test voltage and reference amplitude at the array element 10 in the i-th row and j-th column, can be obtained using the following steps, as shown in FIG9 .

[0090] S101. Based on the pre-acquired test voltage set, the test voltages in the test voltage set are sequentially loaded to the array unit 10 in the i-th row and j-th column; the waveguide probe structure is placed on the array unit 10 in the i-th row and j-th column, and the vector network analyzer transmits a microwave signal of a specific band (for example, 17-21 GHz, a microwave signal in the K band) to the array unit 10 in the i-th row and j-th column through the first feeding port 101 and the second feeding port 102 of the waveguide probe structure. The array unit 10 in the i-th row and j-th column reflects the phase-shifted microwave signal, and the vector network analyzer collects the phase-shifted microwave signal through the first feeding port 101 and the second feeding port 102 of the waveguide probe structure, and analyzes the network parameters of the waveguide probe structure and the array unit 10 in the i-th row and j-th column based on the relationship between the incident and reflected microwave signals, and determines the first reference S parameter matrix. The first reference S parameter matrix includes a first reference phase S parameter matrix and a first reference amplitude S parameter matrix, which are respectively used and Represented by, see equations (1) and (2).

[0091]

[0092]

[0093] Among them, the above formula represents the ratio of the phase of the microwave signal sent from the first feeding port 101 and the amplitude of the microwave signal reflected back from the array unit 10, obtained by the vector network analyzer; represents the ratio of the phase of the microwave signal sent from the second feeding port 102 and the amplitude of the microwave signal reflected from the array unit 100, obtained by the vector network analyzer; represents the phase difference between the amplitude of the microwave signal sent from the first feeding port 101 and the received microwave signal reflected from the array unit 10, obtained by the vector network analyzer; It represents the phase difference between the amplitude of the microwave signal sent from the second feeding port 102 and the received microwave signal reflected from the array unit 10 and obtained by the vector network analyzer.

[0094] The test voltage set may include 53 voltage values ​​ranging from 0V to 16.5V.

[0095] In some examples, in step S101, the waveguide probe structure may contact the antenna array, meaning that the waveguide opening of the waveguide probe structure covers the i-th row, j-th column in array unit 10. Of course, in step S101, a certain distance between the waveguide probe structure and the antenna array is also acceptable. This is sufficient as long as the orthographic projection of the waveguide probe structure on the first dielectric substrate covers the area of ​​the i-th row, j-th column in array unit 10 (and does not cover other areas of array unit 10). It should be noted that the distance between the waveguide probe structure and the antenna array can be kept relatively small, preferably no more than 0.5 mm.

[0096] S102. Place the waveguide probe structure on the reflector assembly. The vector network analyzer transmits a microwave signal of a specific band (for example, 17-21 GHz, a microwave signal in the K band) to the reflector assembly through the first feeding port 101 and the second feeding port 102 of the waveguide probe structure. The reflector assembly reflects the microwave signal. The vector network analyzer collects the microwave signal through the first feeding port 101 and the second feeding port 102 of the waveguide probe structure, and analyzes the network parameters of the waveguide probe structure and the reflector assembly based on the relationship between the incident and reflected microwave signals, and determines the second reference S parameter matrix. The second reference S parameter matrix includes a second reference phase S parameter matrix and a second reference amplitude S parameter matrix, which are respectively used and Representation, see equations (3) and (4).

[0097]

[0098]

[0099] S103. The controller obtains a normalized reference S parameter matrix based on the first reference S parameter matrix and the second reference S parameter matrix. In some examples, step S103 specifically includes subtracting the first reference S parameter matrix from the second reference S parameter matrix vector to obtain a normalized reference S parameter matrix. The normalized reference S parameter matrix includes a normalized reference amplitude S parameter matrix. (See formula (5)) and the normalized reference phase S parameter matrix (See formula (6)).

[0100]

[0101]

[0102] In the disclosed embodiment, the first reference S-parameter matrix is ​​normalized by the second reference S-parameter matrix to obtain a normalized reference S-parameter matrix. This approach eliminates the influence of the waveguide probe structure itself, so that the determined characteristics are only the network parameters of the i-th row and j-th column element based on the relationship between the incident and reflected microwave signals.

[0103] S104 , the controller processes the normalized reference S parameter matrix to determine a corresponding relationship response curve between the test voltage and the reference phase, and a corresponding relationship response curve between the test voltage and the reference amplitude in the i-th row and j-th column of the array unit 10 .

[0104] In some examples, step S104 may include changing the relative units of the normalized reference amplitude S parameter matrix from logarithmic form to linear form. (See formula (7)), the unit of the normalized reference phase S parameter matrix is ​​changed from degrees to radians (See formula (8)), and then the complex form of the normalized reference S parameter matrix S is obtained Norm (See formula (9)), and corresponds to the linear polarization direction.

[0105]

[0106]

[0107]

[0108] If the antenna array operates in linear polarization mode, a response curve of the corresponding relationship between the test voltage and the reference phase in the i-th row and j-th column of the array unit 10 and a response curve of the corresponding relationship between the test voltage and the reference amplitude can be determined based on the complex form of the normalized reference S-parameter matrix.

[0109] If the working mode of the antenna array is circular polarization, it is necessary to perform a linear-circular polarization basis transformation (see formula (10)) and then determine the corresponding relationship response curve between the test voltage and the reference phase in the i-th row and j-th column of the array unit 10, as well as the corresponding relationship response curve between the test voltage and the reference amplitude.

[0110]

[0111] It should be noted that during the process of obtaining the reference phase codebook, if a problem is detected in a particular on-array unit 10 based on the obtained response curves of the test voltage versus reference phase and the test voltage versus reference amplitude for that on-array unit 10, it is necessary to perform the aforementioned test using on-array units 100 adjacent to that on-array unit 100 to identify the on-array unit with the problem. For example, if an on-array unit 100 includes four on-array units, each on-array unit and its adjacent on-array units located in different on-array units 10 form a 2×2 on-array unit 100. Testing is then performed in the aforementioned manner to obtain response curves of the test voltage versus reference phase and the test voltage versus reference amplitude, thereby determining whether the on-array unit 100 has a problem. The problematic on-array unit 100 is removed from the subsequent calibration process, and the normal on-array units 100 in that on-array unit 10 can be calibrated using the aforementioned method using the surrounding on-array units 100 to form an on-array unit 10.

[0112] S12. Analyze and obtain a first S-parameter matrix based on the phase and amplitude of the microwave signal collected by the vector network analyzer at different test voltages in the array unit 10 at the i-th row and j-th column.

[0113] It should be noted that since the vector network analyzer can collect the phase and amplitude of the microwave signal in the network parameters based on the relationship between the incident microwave and the reflected microwave, the first S parameter matrix analyzed at this time includes the first phase S parameter matrix and the first amplitude S parameter matrix.

[0114] In some examples, the first phase S parameter matrix and the first amplitude S parameter matrix obtained by analysis with a vector network analyzer in step S12 may be the same as those in step S101 above, and thus will not be repeated here.

[0115] S13. Process the first S parameter matrix to obtain a normalized S parameter matrix of the antenna unit in the i-th row and j-th column at each test voltage, and determine a target voltage absolute phase response curve and a target voltage amplitude response curve corresponding to the antenna unit in the i-th row and j-th column; the normalized S parameter matrix is ​​used to characterize a reference phase and a reference amplitude of a network parameter microwave signal of the array unit 10 in the i-th row and j-th column under the test voltage, which is established based on the relationship between the incident microwave and the reflected microwave.

[0116] In some examples, step S13 may include the following steps:

[0117] S131. Place the waveguide probe structure on the reflection component. The vector network analyzer transmits a microwave signal of a specific frequency band (for example, 17-21 GHz, a microwave signal in the K band) to the reflection component through the first feeding port 101 and the second feeding port 102 of the waveguide probe structure. The reflection component reflects the microwave signal. The vector network analyzer collects the phase-shifted microwave signal through the first feeding port 101 and the second feeding port 102 of the waveguide probe structure, analyzes the phase and amplitude of the microwave signal, and determines a second S-parameter matrix.

[0118] The method of determining the second S-parameter matrix by the vector network analyzer is the same as that of the above step S102 , and therefore will not be repeated here.

[0119] S132. The controller obtains a normalized calibration S-parameter matrix based on the first S-parameter matrix and the second S-parameter matrix. In some examples, step S132 specifically includes vector-subtracting the first S-parameter matrix from the second S-parameter matrix to obtain a normalized S-parameter matrix. The normalized S-parameter matrix includes a normalized phase S-parameter matrix and a normalized amplitude S-parameter matrix.

[0120] In some examples, in step S132 , the normalized phase S parameter matrix and the normalized amplitude S parameter matrix obtained by processing by the controller may be the same as in step S103 , and thus will not be repeated here.

[0121] S133 , the controller processes the normalized S parameter matrix to determine a corresponding relationship response curve between the test voltage and the reference phase in the i-th row and the j-th column of the array unit 10 , and a corresponding relationship response curve between the test voltage and the reference amplitude.

[0122] In some examples, step S13 may include changing the relative units of the normalized amplitude S parameter matrix from logarithmic form to linear form, changing the units of the normalized phase S parameter matrix from degrees to radians, and then obtaining the complex form of the normalized S parameter matrix, corresponding to the linear polarization direction.

[0123] If the working mode of the antenna array is linear polarization, then the corresponding relationship response curve between the test voltage and phase in the i-th row and j-th column of the array unit 10 and the corresponding relationship response curve between the test voltage and amplitude can be determined based on the complex form of the normalized S-parameter matrix.

[0124] If the working mode of the antenna array is circular polarization, it is necessary to perform a linear-circular polarization basis transformation, and then determine the corresponding relationship response curve between the test voltage and phase and the corresponding relationship response curve between the test voltage and amplitude in the array unit 10 in the i-th row and j-th column.

[0125] By comparing the obtained response curve of the corresponding relationship between the test voltage and the phase with the response curve of the corresponding relationship between the test voltage and the reference phase in the reference phase codebook, the phase error distribution of each in-array unit 10 can be obtained. By comparing the obtained response curve of the corresponding relationship between the test voltage and the amplitude with the response curve of the corresponding relationship between the test voltage and the reference amplitude in the reference phase codebook, the amplitude error distribution of each in-array unit 10 can be obtained.

[0126] In some examples, the antenna array calibration method of the embodiment of the present disclosure also includes a step of calibrating the phase shift of each sub-array of the antenna array to 0° before step S11, thereby leveling the initial phase to ensure the accuracy of the subsequent pure phase shift matching using the relative phase shift curve.

[0127] According to the above calibration method, the antenna array with a working mode of right-hand circular polarization and a working frequency of 19.725 GHz is calibrated. When the beam pointing angle is 90° (normal), one of the array elements 10 is a test area. Combined with Figures 10a, 10b, 11a, 11b, 12a, 12b, 13a, 13b, 13c and 13d, Figure 10a is the main polarization (right-hand circular polarization) voltage-amplitude response curve when the working mode of the antenna array is right-hand circular polarization and a working frequency of 19.725 GHz. Figure 10b is the cross-polarization (left-hand circular polarization) voltage-amplitude response curve when the working mode of the antenna array is right-hand circular polarization and a working frequency of 19.725 GHz. Figure 11a is the main polarization (right-hand circular polarization) voltage-absolute phase response curve when the working mode of the antenna array is right-hand circular polarization and a working frequency of 19.725 GHz. Figure 11b shows the cross-polarization (left-hand circular polarization) voltage-absolute phase response curve when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz. Figure 12a shows the amplitude distribution of the antenna array when the antenna array is calibrated to 0° when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz. Figure 12b shows the phase distribution of the antenna array when the antenna array is calibrated to 0° when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz. Figure 13a shows the amplitude distribution of the antenna array when the antenna array beam angle is 90° when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz. Figure 13b shows the phase distribution of the antenna array when the antenna array beam angle is 90° when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz. Figure 13c shows the theoretical phase distribution of the antenna array when the antenna array beam angle is 90° when the antenna array operates in right-hand circular polarization at a frequency of 19.725 GHz. Figure 13c shows the phase error distribution when the antenna array operates in right-hand circular polarization at 19.725 GHz and has a beam angle of 90°. The average error is -2.6°, and the standard deviation is 6.2°.

[0128] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A waveguide probe structure comprising a waveguide-to-coaxial converter, a gradient waveguide, and a first straight waveguide; wherein: The waveguide-to-coaxial converter is configured to transmit and receive two orthogonal linear polarization signals; The gradient waveguide has a first waveguide cavity, and the first waveguide cavity has a first waveguide port and a second waveguide port arranged along its length; the first waveguide port is connected to the waveguide coaxial converter, and the second waveguide port is connected to the first straight waveguide; the size of the cross section of the first waveguide cavity increases monotonically in the direction from the first waveguide port to the second waveguide port; The first straight waveguide has a second waveguide cavity, and the size of the cross section of the second waveguide cavity is equal to the size of the second waveguide port.

2. The waveguide probe structure according to claim 1, wherein: The waveguide-to-coaxial converter includes a second straight waveguide, a first feeding port, a second feeding port and an isolation component; The feeding directions of the first feeding port and the second feeding port are orthogonal; the second straight waveguide has a third waveguide cavity, and the first feeding port, the second feeding port and the isolation component are all installed on the side wall of the second straight waveguide and extend into the third waveguide cavity; the isolation component is located between the first feeding port and the second feeding port and parallel to one of them.

3. The waveguide probe structure according to claim 2, wherein: The invention also includes a first fixing component, which is installed on the side wall of the second straight waveguide and has a plurality of mounting holes.

4. The waveguide probe structure according to claim 3, wherein: The first fixing assembly includes a flange.

5. The waveguide probe structure according to claim 1, wherein: The waveguide-to-coaxial converter is fixedly connected to the gradient waveguide via a second fixing component.

6. The waveguide probe structure according to claim 5, wherein: The second fixing assembly includes a flange.

7. The waveguide probe structure according to claim 1, wherein: The opening angle of the gradient waveguide is 1.5° to 2.5°.

8. The waveguide probe structure according to any one of claims 1 to 6, wherein: The invention also includes a gasket fixed on the end face of the first straight waveguide facing away from the gradient waveguide.

9. The waveguide probe structure according to any one of claims 1 to 6, wherein: The length of the first straight waveguide is greater than the wavelength corresponding to the center frequency of the transmitted microwave signal.

10. A calibration device for an antenna array, comprising a waveguide probe structure, a vector network analyzer, and a controller; wherein: The waveguide probe structure comprises the waveguide probe structure according to any one of claims 1 to 9; The vector network analyzer is configured to transmit the microwave signal to the array unit to be calibrated through the waveguide probe structure under the control of the controller, and receive the microwave signal reflected by the array unit and transmitted through the waveguide probe structure, and analyze the received microwave signal to obtain the network parameters of the array unit based on the relationship between the incident microwave and the reflected microwave. The controller is configured to analyze the vector network analyzer to obtain network parameters based on the relationship between the incident microwave and the reflected microwave, and obtain a calibration error through a preset algorithm.

11. A method for calibrating an antenna array, the method using the calibration device according to claim 10; the antenna array comprising M×N array elements, where one of M and N is a positive integer greater than or equal to 1, and the other is a positive integer greater than or equal to 2; the method comprising: Based on the pre-acquired reference phase codebook, the M×N array elements are calibrated in sequence; The reference phase codebook includes corresponding relationships between multiple test voltages and reference amplitudes and reference phases; The steps of calibrating the array unit for the i-th row and j-th column include: Sequentially loading the test voltages in the reference phase codebook to the array unit in the i-th row and j-th column, and after each loading of the test voltage, transmitting the microwave signal radiated by the array unit in the i-th row and j-th column to a vector network analyzer through a waveguide probe structure, so that the vector network analyzer collects the network parameters of the array unit in the i-th row and j-th column based on the relationship between the incident microwave and the reflected microwave; 0 < i ≤ M, 0 < j ≤ N, i and j are both positive integers; Based on the array unit in the i-th row and j-th column, under different test voltages, the vector network analyzes network parameters based on the relationship between the incident microwave and the reflected microwave to obtain a first S parameter matrix; The controller processes the first S parameter matrix to obtain a normalized S parameter matrix of the antenna unit in the i-th row and j-th column under each test voltage, and determines a target voltage absolute phase response curve and a target voltage amplitude response curve corresponding to the antenna unit in the i-th row and j-th column; the normalized S parameter matrix is ​​used to characterize the network parameters of the array unit in the i-th row and j-th column under the test voltage based on the relationship between the incident microwave and the reflected microwave.

12. The antenna array calibration method according to claim 11, wherein: The step of processing the first S parameter matrix to obtain a normalized S parameter matrix of the antenna unit in the i-th row and j-th column at each test voltage includes: placing the waveguide probe structure on a reflective component, and transmitting a microwave signal reflected by the reflective component to a vector network analyzer via the waveguide probe structure, so that the vector network analyzer analyzes the waveguide probe structure and the reflective component to establish network parameters based on a relationship between incident and reflected microwave signals; The vector network analyzer determines a second S-parameter matrix based on the waveguide probe structure and the reflective component obtained by analysis and network parameters based on the relationship between the incident and reflected microwave signals; The controller obtains a normalized S parameter matrix of the antenna unit in the i-th row and j-th column at each test voltage based on vector subtraction between the first S parameter matrix and the second S parameter matrix.

13. The antenna array calibration method according to claim 11 or 12, wherein: When the operating mode of the antenna array is circular polarization, the step of determining the target voltage absolute phase response curve and the target voltage amplitude response curve corresponding to the antenna unit in the i-th row and j-th column includes: The normalized S parameter matrix is ​​transformed into a linear-circular polarization basis to determine a target voltage absolute phase response curve and a target voltage amplitude response curve corresponding to the antenna unit in the i-th row and j-th column.

14. The antenna array calibration method according to claim 11, wherein: The method further includes the step of obtaining a reference phase codebook; the reference phase codebook includes a corresponding relationship response curve between the test voltage and the reference phase of each array unit, and a corresponding relationship response curve between the test voltage and the reference amplitude; Acquiring the response curve of the corresponding relationship between the test voltage and the reference phase, and the response curve of the corresponding relationship between the test voltage and the reference amplitude in the array unit in the i-th row and j-th column includes: Based on a pre-acquired test voltage set, the test voltages in the test voltage set are sequentially loaded onto the array unit in the i-th row and j-th column; a waveguide probe structure is placed on the array unit in the i-th row and j-th column, and a vector network analyzer obtains network parameters of the array unit in the i-th row and j-th column and the waveguide probe structure based on a relationship between incident and reflected microwave signals through waveguide probe structure analysis, thereby determining a first reference S-parameter matrix; 0 < i ≤ M, 0 < j ≤ N, where i and j are both positive integers; Placing the waveguide probe structure on the reflective component, and using a vector network analyzer to analyze network parameters of the reflective component and the waveguide probe structure based on a relationship between incident and reflected microwave signals, thereby determining a second reference S-parameter matrix; The controller obtains a normalized reference S parameter matrix based on the first reference S parameter matrix and the second reference S parameter matrix, and processes the normalized reference S parameter matrix to determine a corresponding relationship response curve between the test voltage and the reference phase in the i-th row and j-th column of the array unit, as well as a corresponding relationship response curve between the test voltage and the reference amplitude.

15. The antenna array calibration method according to claim 11, wherein: The reflective component is made of copper or aluminum.

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