Far-field calibration method for full-channel open array antenna, electronic equipment and storage medium

Abstract

The invention discloses a full-channel open array antenna far-field calibration method, electronic equipment and a storage medium. The method comprises the following steps: establishing a two-dimensional plane mathematical model of a to-be-calibrated array antenna; obtaining coordinate data of each array unit in the array antenna model; dividing the overall directional diagram by the active unit directional diagram to obtain a first array factor; converting the first array factor into a () space to obtain a second array factor; determining a sampling point according to the second array factor; calculating to obtain a weighting coefficient matrix according to the coordinate data of the sampling points and the coordinate data of the array units; and calculating array excitation information according to the weighting coefficient matrix and the second array factor to complete array backstepping calibration. According to the method, all-channel opening backstepping calibration can be carried out on the array antenna with the non-half-wavelength array spacing and irregular arrangement, almost no requirement for array factors exists, and the application range is obviously expanded.

Description

Technical Field

[0001] The present invention relates to the field of array antenna back-calculation calibration, and in particular to a far-field calibration method, electronic equipment and storage medium for a full-channel open array antenna. Background Art

[0002] In active phased array, it is common that each antenna unit has a corresponding T / R module, that is, one channel corresponds to one unit antenna. The general form of planar array antenna is as follows: Figure 1 This method allows for independent and precise control of each antenna element. The array antenna can be calibrated using various methods, including the rotating electric vector method and the phase-commutation measurement method. However, for fully open array antennas, it is impossible to control the switching of individual elements, so the traditional calibration method (rotating electric vector method) cannot be used. In this case, a comprehensive FFT-based method can be used for inverse calculation, but this method has some problems: The existing full-channel open array antenna calibration method has the following shortcomings: (1) The FFT-based comprehensive inverse method has strict requirements on the array spacing. For a linear array, the array factor expression is as follows: (1) Where, Represents the coordinate of the u direction in the u,v space, which can be understood as the x in f(x). express The array factor, n represents the nth unit in the array; N represents the unit summary in the array; represents the current amplitude and phase corresponding to the nth unit; k represents the coordinate index in the u direction and the kth point in the u direction; K represents the total number of grid points in the u direction; d represents the array spacing; Indicates wavelength; The expression for the inverse Fourier transform is as follows: (2) Where, the inverse Fourier transform converts the data from the frequency domain to the time domain, Represents a discrete sequence in the time domain, and n is the index of the time domain sampling point; Represents a discrete sequence in the frequency domain, representing the complex amplitude of different frequency components, and k is the index of the frequency domain sampling point.

[0003] Based on equations (1) and (2), if FFT transformation can be applied to the calculation of array antenna patterns, the following corresponding relationship must be satisfied: (3) because and ,but This condition must be met, that is, only the array antenna back-calculation with an array spacing of half a wavelength can be processed.

[0004] (2) The FFT-based integrated inverse method has strict requirements for the array layout. In the above point (1), it has been made clear that if you want to use the FFT integrated method to calibrate the array antenna, the array spacing must be half a wavelength. This also means that the array antenna can only be arranged in a regular array at this time, and it cannot handle array inverse in sparse arrays.

[0005] (3) The FFT-based comprehensive inverse method has certain requirements for the array factor. This method is to inversely infer the array excitation situation by performing FFT transformation on the input array factor. The ideal array factor range of the algorithm is -1≤u≤1, -1≤v≤1 (for a one-dimensional array, it is generally only the u in the u,v space; for a two-dimensional array, it needs to include the entire u,v two-dimensional space; it can be understood as x relative to xy, that is, the relationship between the one-dimensional line vector and the two-dimensional plane). However, the array factor in the (u,v) space obtained in the actual test is limited to the range of u^2+v^2≤1, as shown in the attached figure. Figure 2 As shown in the figure, it can be seen that compared with the (u,v) space range of the ideal array factor, the (u,v) space given by the actual test is reduced. This also means that the calibration method has certain requirements for the array factor, that is, the effective information of the array factor should be distributed as much as possible in the range of u^2+v^2≤1, which also limits the use scenario of the calibration method to a certain extent. Summary of the Invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a far-field calibration method, electronic equipment and storage medium for a full-channel open array antenna.

[0007] The object of the present invention is achieved through the following technical solutions: A first aspect of the present invention provides a far-field calibration method for an all-channel open array antenna, comprising the following steps: Establish a two-dimensional plane mathematical model of the array antenna to be calibrated and determine the global rectangular coordinate system of the array antenna model; Get the coordinates of each array element in the array antenna model in the global rectangular coordinate system. Coordinate data; Obtain the overall radiation pattern of the array antenna to be calibrated by actual measurement , and obtain the active unit pattern of the central array unit of the array antenna model through simulation ; The overall direction map Divided by the active unit pattern Get the first factor ,Right now ;in represents the pitch angle, Indicates azimuth; The first factor Depend on( Space conversion to ( ) space to obtain the second array factor ,in ; Based on the second factor exist The number of sampling points P is selected based on the spatial distribution, and the sampling points are determined to be spatial Coordinate data and the second matrix factor corresponding to the sampling point ; Based on the sampling point Coordinate data and array elements Coordinate data, calculate the weight coefficient matrix A; According to the weighted coefficient matrix A and the second matrix factor =b to calculate the array excitation information x, and the calculation formula is Ax=b; thus completing the array back-calculation.

[0008] Furthermore, the simulation method includes HFSS or CST.

[0009] Furthermore, the weighted coefficient matrix A and the second matrix factor =b calculates array excitation information x, including: Perform matrix singular value decomposition on the weight coefficient matrix A and solve the matrix singular value based on the SVD method. ,in is the left singular component; is a singular value; for ; Singular Values Processing, using different methods to process singular values ​​according to the different properties of the system ; Project the right end vertex and calculate the orthogonal projection of the left singular vector space , ; Solve the scaling transformation, and perform scaling transformation on the singular value of each non-zero singular component according to the corresponding method of singular value processing based on the different properties of the system; The right singular vectors are reconstructed to obtain the final solution.

[0010] Furthermore, the singular values ​​are processed in different ways according to different properties of the system, including: For stable systems, the direct pseudo-inverse method is used; For ill-conditioned systems, regularization is used method.

[0011] Furthermore, the ill-conditioned system refers to a system of equations that is extremely sensitive to small changes in input data including the coefficient matrix and the right-hand end vertex, resulting in a significant amplification of the solution error; the opposite is true for a stable system.

[0012] According to a second aspect of the present invention, an electronic device is provided, comprising a storage unit and a processing unit, wherein the storage unit stores computer instructions that can be run on the processing unit, and when the processing unit runs the computer instructions, the steps of the full-channel open array antenna far-field calibration method as described in the first aspect are executed.

[0013] According to a third aspect of the present invention, a storage medium is provided on which computer instructions are stored. When the computer instructions are executed, the steps of the far-field calibration method of the full-channel open array antenna as described in the first aspect are executed.

[0014] The beneficial effects of the present invention are: The calibration method in this exemplary embodiment uses mathematical derivation to clarify the relationship between array factor and array excitation, and establishes a mathematical model for inversely inferring the array excitation algorithm from the array factor. This method breaks away from traditional FFT synthesis concepts, eliminating the issues inherent in traditional FFT synthesis inverse algorithms, such as the requirement for half-wavelength array spacing and a regular array layout.

[0015] Based on this calibration method, full-channel open reverse calibration can be performed on array antennas with non-half-wavelength array spacing and irregular arrays, and there are almost no requirements for the array factor, which also significantly expands the application scope of this method (compared to traditional calibration methods). BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a general planar array antenna in the prior art; Figure 2 In the existing technology Space diagram; Figure 3 The present invention provides a flowchart of a far-field calibration method for a full-channel open array antenna according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0017] The technical solution of the present invention is described clearly and completely below with reference to the accompanying drawings. It is apparent that the embodiments described are only a portion of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0018] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as "center," "up," "down," "left," "right," "vertical," "horizontal," "inside," and "outside" are based on the directions or positional relationships described in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0019] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention.

[0020] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0021] First, the implementation logic of this method is explained, taking a two-dimensional plane array as an example: For a two-dimensional planar array with M rows and N columns, assume that the two-dimensional planar array has Q units; the number of sampling points in the u, v space is P. Its array factor and array element position And the relationship between incentive settings is as follows: (4) In formula (4), Represents the matrix factor, which is a matrix containing Direction and Two-dimensional function of direction; Represents the excitation (including amplitude and phase) of the m-row and n-column unit; Indicates the position of the m-row and n-column unit in the x direction; Indicates the position of the m-row and n-column unit in the x direction; , , k represents the wave number ( ), which is wavelength dependent. For a fixed and , expand formula (4) to get: (5) In formula (5), 、 are all known quantities related to m and n, The physical meaning of the array is Unit pairs The first in space The weighted effect of the sampling points, 、 For the array excitation setting, further expand Equation (4) to: (6) Equation (6) can be further simplified to: (7) It can be seen from formula (7) that if If the matrix is ​​known, the matrix can be solved to obtain (array excitation), The specific solution formula is as follows: (8) From formula (8), we can see that for Any one in the matrix , if the corresponding and 、 and Known, the corresponding weighting coefficient can be solved.

[0022] See also Figure 3 , Figure 3 A flowchart of a far-field calibration method for an all-channel open array antenna provided in an exemplary embodiment of the present invention is shown, comprising the following steps: S1: Establish a two-dimensional plane mathematical model of the array antenna to be calibrated and determine the global rectangular coordinate system of the array antenna model.

[0023] In a specific exemplary embodiment, the array antenna unit size is 64 (Q=64), the array spacing is 15mm, and the operating frequency is 8GHz-12GHz (i.e., the ratio of array spacing to wavelength is 0.4-0.6). The global rectangular coordinate system is established with the geometric center of the array antenna in the two-dimensional plane as the origin of the global coordinate system. , For the direction of transmission, The plane is the plane of the array.

[0024] S2: Get the coordinates of each array element in the array antenna model in the global rectangular coordinate system Coordinate data.

[0025] In a specific exemplary embodiment, each array element is abstracted as a particle on a plane, and the position of the particle is determined by the position of the physical geometric center of each element in the array in the global coordinate system. For each element q, its position in the global coordinate system can be obtained. Position information on a plane .

[0026] S3: Obtain the overall radiation pattern of the array antenna to be calibrated by actual measurement , and obtain the active unit pattern of the central array unit of the array antenna model through simulation ; The overall direction map Divided by the active unit pattern Get the first factor ,Right now in represents the pitch angle, Indicates the azimuth.

[0027] In a specific exemplary embodiment, the overall directional pattern of the array antenna is obtained by actual measurement in a darkroom. , obtain the active unit pattern of a central unit of the array through HFSS or CST simulation Finally, Calculated The first factor in space .

[0028] S4: The first array factor Depend on( Space conversion to ( ) space to obtain the second array factor ,in .

[0029] S5: Based on the second array factor exist The distribution of space selects the number of sampling points P , and determine the sampling point at spatial The coordinate information of the coordinate data and the corresponding , , Q is the number of array elements in the array antenna to be calibrated; S6: Based on the sampling point Coordinate data and array elements Coordinate data, calculate the weight coefficient matrix A; The expression is as follows: in, The solution formula is as follows: in, represents the wave number, is the antenna operating frequency, is the speed of light; and Respectively represent the Units in Direction and Coordinates of direction; and Respectively The first in space Sampling points in Direction and The coordinate of the direction, k represents the wave number. The physical meaning of the array is Unit pairs The first in space The weighted effect of the sampling points.

[0030] S7: According to the weighted coefficient matrix A and the second matrix factor =b to calculate the array excitation information x, the calculation formula is Ax=b; thus completing the array back-calculation. Among them, the relevant equations are established based on the array factor solution principle , the equations are expressed as follows: Among them, the coefficient matrix It is known that the array factor matrix It is known that the array excitation information matrix , and then solve the system of equations to get the solution of x.

[0031] In summary, the calibration method in this exemplary embodiment uses mathematical derivation to clarify the relationship between array factor and array excitation, and establishes a mathematical model for inversely inferring the array excitation algorithm from the array factor. This method breaks away from traditional FFT synthesis concepts, eliminating the issues inherent in traditional FFT synthesis inverse algorithms, such as the requirement for half-wavelength array spacing and a regular array layout.

[0032] Based on this calibration method, full-channel open reverse calibration can be performed on array antennas with non-half-wavelength array spacing and irregular arrays, and there are almost no requirements for the array factor, which also significantly expands the application scope of this method (compared to traditional calibration methods).

[0033] More preferably, in an exemplary embodiment, the weighted coefficient matrix A and the second matrix factor =b calculates array excitation information x, including: S8: Perform matrix singular value decomposition on the weighted coefficient matrix A and solve the matrix singular value based on the SVD method. ,;in for Orthogonal matrix, representing the left singular component; for Diagonal matrix, elements , represents the singular value; for Orthogonal matrix, representing the right singular components; The value of each element can be solved by the corresponding function of Matlab.

[0034] S9: Singular Values Processing, using different methods to process singular values ​​according to the different properties of the system In a specific exemplary embodiment, the singular values ​​are processed in different ways according to different properties of the system, including: For stable systems, a direct pseudo-inverse method is used: For ill-conditioned systems, regularization is used method: Where, Indicates wavelength.

[0035] It should be noted that the so-called pathological system refers to a system of equations that is extremely sensitive to slight changes in the input data, including the coefficient matrix and the right-hand end vertex, resulting in a significant amplification of the error of the solution; the opposite is true for a stable system; generally in mathematics, it can be directly judged by the norm condition number of the coefficient matrix A; the larger its value, the more serious the system pathology; and in actual engineering applications, a preset standard threshold is used (that is, the condition number is greater than the preset standard threshold, which means it is considered to be a pathological system) to determine whether the system is pathological.

[0036] S10: Project the right end vertex and calculate the orthogonal projection of the left singular vector space; The c vector is obtained in step S10, which lays the foundation for solving the d vector in step 11. The b here corresponds to the b in Ax=b. It is obtained by the singular value decomposition of the matrix in step S8; c is the intermediate variable obtained after projection, which is convenient for subsequent use.

[0037] It should be noted that for this step: First, perform singular value decomposition on matrix A: ; Among them, the left singular matrix U is an orthogonal matrix, which is the standard orthogonal basis of the output space; the right singular matrix V is the standard orthogonal basis of the input space.

[0038] Then on this basis, the projection right end top .

[0039] (This is why left singular vectors are introduced.) Its mathematical essence is to transform the problem into an optimal coordinate system, thereby decoupling the original system of equations and facilitating solution and regularization. The b here is the b in Ax=b.

[0040] S11: Descaling transformation, performing scaling transformation on the singular value of each non-zero singular component according to the corresponding method of singular value processing based on the different properties of the system; The essence of this step is to suppress the negative impact of small singular values ​​on the solution by modifying the inverse of the singular values, thereby achieving the separation of the physical dominant mode and the noise mode.

[0041] S12: Reconstruct the right singular vectors to obtain the final solution.

[0042] In mathematical logic, in step 12, x is obtained by multiplying the V vector and the d vector, wherein the V vector is obtained by the matrix singular value decomposition in step S8, and the d vector is obtained by the scaling transformation in step S11.

[0043] It should be noted that, first, S10 is used to determine the coordinate c of the right vertex b in the left singular space U. Second, S11 is used to solve the right projection signal c to obtain d. Its physical essence is to achieve the transformation from signal space to source space. The numerical function can control the propagation of pathological systems through scaling. Finally, S12 is used to solve d and V to obtain the final solution. Here, V is the right singular matrix (obtained by S8), and d is the scaled coefficient vector (obtained by S11). With the same inventive concept as the above exemplary embodiment, another exemplary embodiment of the present invention provides an electronic device, comprising a storage unit and a processing unit, wherein the storage unit stores computer instructions that can be executed on the processing unit, and when the processing unit executes the computer instructions, the processing unit executes the following Figure 1 The steps of the far-field calibration method of the full-channel open array antenna.

[0044] The electronic device is implemented as a general-purpose computing device. Components of the electronic device may include, but are not limited to, the at least one processing unit, the at least one storage unit, and a bus connecting different system components (including the storage unit and the processing unit).

[0045] The storage unit stores program codes that can be executed by the processing unit, so that the processing unit performs the steps according to various exemplary embodiments of the present invention described in the "Exemplary Method" section above. For example, the processing unit can perform the following steps: Figure 1 The method shown in .

[0046] The storage unit may include a readable medium in the form of a volatile memory unit, such as a random access memory unit (RAM) and / or a cache memory unit, and may further include a read-only memory unit (ROM).

[0047] The storage unit may also include a program / utility having a set (at least one) of program modules, such program modules including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0048] The bus can represent one or more of several types of bus structures, including a memory unit bus or memory unit controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus architectures.

[0049] The electronic device may also communicate with one or more external devices (e.g., keyboards, pointing devices, Bluetooth devices, etc.), one or more devices that enable a user to interact with the electronic device, and / or any device that enables the electronic device to communicate with one or more other computing devices (e.g., routers, modems, etc.). Such communication may be performed via an input / output (I / O) interface. Furthermore, the electronic device may also communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) via a network adapter. The network adapter communicates with other modules of the electronic device via a bus. It should be understood that other hardware and / or software modules may be used in conjunction with the electronic device, including but not limited to microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0050] Through the above description, it is easy for those skilled in the art to understand that the example embodiments described herein can be implemented through software or through a combination of software and necessary hardware. Therefore, the technical solution according to this exemplary embodiment can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, a USB flash drive, a mobile hard drive, etc.) or on a network, and includes several instructions to enable a computing device (such as a personal computer, a server, a terminal device, or a network device, etc.) to execute the method according to this exemplary embodiment.

[0051] With the same inventive concept as the above exemplary embodiment, another exemplary embodiment of the present invention provides a storage medium having computer instructions stored thereon, which, when executed, execute the steps of the full-channel open array antenna far-field calibration method as described in the first aspect.

[0052] Based on this understanding, the technical solution of this embodiment, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product (program product). The computer software product is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention.

[0053] The program product may be implemented in any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or component, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0054] A computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable signal medium may also be any readable medium other than a readable storage medium that can transmit, propagate, or transfer a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0055] The program code embodied on the readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0056] The program code for performing the operations of the present invention may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, and the like, as well as conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a stand-alone software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving a remote computing device, the remote computing device may be connected to the user computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0057] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications can be made based on the above descriptions. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications derived therefrom remain within the scope of protection of the present invention.

Claims

1. A far-field calibration method for an array antenna with all channels open, characterized by: The following steps are involved: Establish a two-dimensional plane mathematical model of the array antenna to be calibrated and determine the global rectangular coordinate system of the array antenna model; Get the coordinates of each array element in the array antenna model in the global rectangular coordinate system. Coordinate data; Obtain the overall radiation pattern of the array antenna to be calibrated by actual measurement , and obtain the active unit pattern of the central array unit of the array antenna model through simulation ; The overall direction map Divided by the active element pattern Get the first factor ,Right now ;in represents the pitch angle, Indicates azimuth; The first factor Depend on( Space conversion to ( ) space to obtain the second array factor ,in ; Based on the second factor exist The number of sampling points P is selected based on the spatial distribution, and the sampling points are determined to be spatial Coordinate data and the second matrix factor corresponding to the sampling point ; Based on the sampling point Coordinate data and array elements Coordinate data, calculate the weight coefficient matrix A; According to the weighted coefficient matrix A and the second matrix factor =b to calculate the array excitation information x, and the calculation formula is Ax=b; thus completing the array back-calculation.

2. The far-field calibration method for an all-channel open array antenna according to claim 1, characterized in that: The simulation method includes HFSS or CST.

3. The far-field calibration method for an all-channel open array antenna according to claim 1, characterized in that: According to the weighting coefficient matrix A and the second matrix factor =b calculates array excitation information x, including: Perform matrix singular value decomposition on the weight coefficient matrix A and solve the matrix singular value based on the SVD method. ,in is the left singular component; is a singular value; for ; Singular Values Processing, using different methods to process singular values ​​according to the different properties of the system ; Project the right end vertex and calculate the orthogonal projection of the left singular vector space , ; Solve the scaling transformation, and perform scaling transformation on the singular value of each non-zero singular component according to the corresponding method of singular value processing based on the different properties of the system; The right singular vectors are reconstructed to obtain the final solution.

4. The far-field calibration method for an all-channel open array antenna according to claim 3, characterized in that: The singular values ​​are processed in different ways according to the different properties of the system, including: For stable systems, the direct pseudo-inverse method is used; For ill-conditioned systems, regularization is used method.

5. The far-field calibration method for an all-channel open array antenna according to claim 4, characterized in that: The ill-conditioned system refers to a system of equations that is extremely sensitive to small changes in input data including the coefficient matrix and the right-hand end vertex, resulting in a significant amplification of the error in the solution; the opposite is true for a stable system.

6. An electronic device comprising a storage unit and a processing unit, wherein the storage unit stores computer instructions that can be executed on the processing unit, characterized in that: When the processing unit runs the computer instructions, the processing unit performs the steps of the full-channel open array antenna far-field calibration method as described in any one of claims 1 to 5.

7. A storage medium having computer instructions stored thereon, characterized in that: When the computer instructions are executed, the steps of the full-channel open array antenna far-field calibration method as described in any one of claims 1 to 5 are executed.

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