A phased array radar far-field beamforming system and beamforming method

Abstract

The application provides a phased array radar far-field beam forming system and a beam forming method, and belongs to the technical field of phased array radars, and solves the problem that a large amount of time and operation resources are consumed in the simulation verification process of a traditional phased array antenna and a radome, wherein the forming system comprises an amplitude weighting array generation module, an array topology structure design lookup table database, a software module and an antenna array simulation module; the software module comprises human-computer interface submodules, input data submodules, program calling submodules and data output submodules which are sequentially connected; the amplitude weighting array generation module, the array topology structure design lookup table database and the antenna array simulation module are bidirectionally and communicatively connected with the program calling submodules, and an antenna array simulation program comprises beam pointing control submodules, phase weighting array generation submodules, array beam simulation submodules and simulation parameter output submodules which are sequentially connected.

Description

Technical Field

[0001] This invention relates to a phased array radar far-field beamforming system and beamforming method, belonging to the field of phased array radar technology. Background Technology

[0002] Phased array antennas can control the amplitude and phase of each element to regulate the array's amplitude and phase distribution, thereby achieving the desired beamforming state. In practical applications of phased array antennas, a radome structure is often added depending on the application scenario. The radome isolates the radar antenna from the external environment, forming a relatively sealed space inside. This protects the radar antenna within the radome from interference from harsh external environments, making the use and maintenance of the antenna array more convenient, improving the reliability of electronic components, and extending the radar's service life. However, because the structure and materials of the radome itself affect the radiation characteristics of the internal antenna, it is necessary to simulate the effects of the antenna array beam and the radome on the internal antenna during the design of phased array antennas and their radomes.

[0003] Traditional phased array antenna and radome design often requires starting from the array elements, designing a reasonable array topology and feeding circuit based on the required array far-field beam parameters, and then verifying the design through simulation software after completing the corresponding structural and parameter design. This process often consumes a lot of time and computing resources. Summary of the Invention

[0004] To address the problem that traditional phased array antenna and radome simulation verification processes require significant time and computational resources, this invention proposes a phased array radar far-field beamforming system and beamforming method.

[0005] The technical solution adopted by the present invention to solve the above problems is as follows: The phased array radar far-field beamforming system proposed by the present invention includes an amplitude weighted array generation module, an array topology design lookup table database, a software module, and an antenna array simulation module;

[0006] The software module provides a user input data page and a human-computer interaction page, calls different modules, and outputs the calculation results of the amplitude-weighted array generation module, the array topology design lookup database, and the antenna array simulation module as the overall array beam control design scheme.

[0007] The amplitude weighting array generation module calculates the amplitude weighting array required for beamforming based on the amplitude weighting matrix of the user input data using the inseparable Chebyshev matrix and transmits it to the software module.

[0008] The array topology design lookup database is based on the user's requirements for array size. It obtains high-dimensional matrix data by linearly fitting the relationship between array topology and array beam main lobe width and main and side lobe gain, and then looks up the data in a table to obtain the array topology design scheme and transmit it to the software module.

[0009] The antenna array simulation module is used to simulate and verify the topology design scheme of the array. It obtains the phase weighting matrix in the design scheme through the beam pointing control calculation relationship of the phased array, outputs the antenna far-field radiation pattern required by the corresponding scheme, and transmits it to the software module.

[0010] Preferably, the software module includes a human-computer interface submodule, an input data submodule, a program call submodule, and a data output submodule connected in sequence;

[0011] The human-computer interface submodule is used for human-computer interaction;

[0012] The input data submodule is used to receive the expected antenna array performance data input by the user, which includes the expected main lobe width, main lobe gain, side lobe gain, and array size.

[0013] The program calls sub-modules for the amplitude-weighted array generation module, the array topology design lookup database, and the antenna array simulation module to design the overall array beam control scheme.

[0014] The data output submodule is used to output the overall array beam control design scheme.

[0015] Preferably, the amplitude-weighted array generation module, the array topology design lookup database, and the antenna array simulation module are all bidirectionally connected to the program calling submodule.

[0016] Preferably, the antenna array simulation program includes a beam pointing control submodule, a phase-weighted array generation submodule, an array beam simulation submodule, and a simulation parameter output submodule connected in sequence.

[0017] The beam pointing control submodule is used to calculate the beam pointing control relationship of the phased array;

[0018] The phase-weighted array generation submodule is used to calculate the phase distribution relationship and, in conjunction with the phased array beam pointing control relationship, calculate the phase-weighted matrix of the array topology design scheme.

[0019] The array beam simulation submodule is used to calculate the antenna far-field pattern required for array topology design.

[0020] The simulation parameter output submodule is used to transmit the phase weighting matrix and antenna far-field pattern to the software module.

[0021] A method for far-field beamforming in phased array radar includes:

[0022] Step 1: The user inputs the expected array size, main lobe width, main lobe gain, and side lobe gain through the human-machine interface submodule and the data input submodule;

[0023] Step 2: Call the amplitude weighted array generation module through the program call submodule. Based on the amplitude weighted matrix of the user input data, calculate the amplitude weighted array required for beamforming using the inseparable Chebyshev matrix and transmit it to the software module.

[0024] Step 3: The program calls the array topology design lookup database through the submodule. Based on the expected array size, main lobe and side lobe gain and main lobe width, the array cell spacing parameters are obtained by querying the high-dimensional matrix obtained by fitting the linear relationship between the array topology and the corresponding parameters. The array topology design scheme is then obtained and transmitted to the software module.

[0025] Step 4: Call the antenna array simulation module through the program calling submodule to simulate the obtained amplitude-weighted array and array topology design scheme;

[0026] Step 5: Obtain the phase weighting matrix in the design scheme through the beam pointing control submodule, phase weighting array generation submodule and array beam simulation submodule, output the corresponding required antenna far-field radiation pattern and transmit it to the software module through the simulation parameter output submodule;

[0027] Step 6: The software module takes the received amplitude weighting matrix, phase weighting matrix and array topology design as the overall array beam control design and outputs them through the data output submodule.

[0028] The beneficial effects of this invention are:

[0029] (1) This invention can adjust different array beam parameters according to different array sizes and application requirements, including main lobe width, main lobe gain, side lobe gain and beam pointing, and can adjust the simulation accuracy according to different requirements to achieve a balance between simulation speed and accuracy requirements.

[0030] (2) The present invention can quickly provide the corresponding array far-field radiation pattern and the corresponding array design scheme according to the required parameters, which can be used for verification work such as radome design, saving the required resources and time to a certain extent.

[0031] (3) The present invention uses an inseparable Chebyshev matrix to regulate the main and side lobe gain of the array far-field beam. Compared with the traditional Chebyshev matrix, the regulation scheme can only achieve Chebyshev distribution and corresponding gain control in the horizontal and vertical directions. The present invention has the feature that it has Chebyshev distribution in any section in the beam pointing direction and can guarantee the gain control effect at the same time.

[0032] (4) The present invention can be adapted to various types of array element antennas. By importing the far-field radiation pattern of the corresponding array element antenna, the present invention can design a control scheme based on its specific characteristic parameters to adapt to the corresponding array. Attached Figure Description

[0033] Figure 1 A structural block diagram of a phased array radar far-field beamforming system provided by the present invention;

[0034] Figure 2 This is a schematic diagram of the distribution of the inseparable Chebyshev matrix provided by the present invention. Figure 2 In the diagram, (a) is a schematic diagram of the current distribution weighting matrix of the array, and (b) is the far-field pattern of the array.

[0035] Figure 3 This is a schematic diagram illustrating the main lobe and side lobe gain control effect provided by the present invention.

[0036] Figure 4 This is a schematic diagram illustrating the effect of main lobe width control provided by the present invention.

[0037] Figure 5 A schematic diagram illustrating the control effect when the beam pointing at -30° in the horizontal direction, as provided by this invention;

[0038] Figure 6 A schematic diagram illustrating the control effect when the beam pointing is 10° horizontally and -20° pitch, as provided by the present invention.

[0039] Figure 7 This is a flowchart illustrating a phased array radar far-field beamforming method provided by the present invention. Detailed Implementation

[0040] Specific implementation method one: as follows Figure 1 As shown, the structure of a phased array radar far-field beamforming system according to this embodiment includes:

[0041] Amplitude-weighted array generation module, array topology design lookup database, software module, and antenna array simulation module;

[0042] The amplitude weighting array generation module calculates the amplitude weighting array required for beamforming based on the amplitude weighting matrix of the user input data using the inseparable Chebyshev matrix and transmits it to the software module.

[0043] The array topology design lookup database is based on the user's requirements for array size. It obtains high-dimensional matrix data by linearly fitting the relationship between array topology and array beam main lobe width and main and side lobe gain, and then looks up the data in a table to obtain the array topology design scheme and transmit it to the software module.

[0044] The software module includes a human-machine interface submodule, an input data submodule, a program call submodule, and a data output submodule connected in sequence. It is used to provide a user input data page and a human-machine interaction page, call different modules, and output the calculation results of the amplitude-weighted array generation module, the array topology design lookup database, and the antenna array simulation module as the overall array beam control design scheme. The amplitude-weighted array generation module, the array topology design lookup database, and the antenna array simulation module are all bidirectionally connected to the program call submodule.

[0045] The human-machine interface submodule is used for human-machine interaction; the input data submodule is used to receive the expected antenna array performance data input by the user, which includes the expected main lobe width, main lobe gain, side lobe gain, and array size; the program call submodule is used for the amplitude-weighted array generation module, the array topology design lookup database, and the antenna array simulation module to design the overall array beam control scheme; the data output submodule is used to output the overall array beam control design scheme.

[0046] The human-computer interface submodule of the software module is divided into three functional areas: input parameter area, output parameter area, and image display area. The input parameter area allows users to input parameters such as the array size, main lobe width, main and side lobe gain, and beam pointing, and can select between 1-degree and 0.1-degree resolutions according to different needs. The output parameter area displays the actual parameters of the array beam generated by the program and outputs the specific array design scheme corresponding to the beam as a data file in the corresponding format. The image display area visually displays the array beam and array design scheme generated by the program in the form of images.

[0047] The antenna array simulation module includes a beam pointing control submodule, a phase weighted array generation submodule, an array beam simulation submodule, and a simulation parameter output submodule connected in sequence. It is used to simulate and verify the topology design scheme of the array, obtain the phase weighting matrix in the design scheme through the beam pointing control calculation relationship of the phased array, output the antenna far-field radiation pattern required by the corresponding scheme, and transmit it to the software module.

[0048] The beam pointing control submodule is used to calculate the beam pointing control relationship of the phased array; the phase weighted array generation submodule is used to calculate the phase distribution relationship and, in combination with the phased array beam pointing control relationship, calculate the phase weighted matrix of the array topology design scheme; the array beam simulation submodule is used to calculate the antenna far-field pattern required for the array topology design scheme; and the simulation parameter output submodule is used to transmit the phase weighted matrix and the antenna far-field pattern to the software module.

[0049] Specific Implementation Method Two: Combining Figure 2-7 This embodiment will be described as follows: Figure 7 As shown, the steps of the phased array radar far-field beamforming method described in this embodiment include:

[0050] S1: The user inputs the expected array size, main lobe width, main lobe gain, and side lobe gain through the human-machine interface submodule and the data input submodule;

[0051] S2: The amplitude weighting array generation module is called through the program calling submodule. Based on the amplitude weighting matrix of the user input data, the amplitude weighting array required for the corresponding beamforming is calculated using the inseparable Chebyshev matrix and transmitted to the software module.

[0052] Main and side lobe gain control: This implementation achieves main and side lobe gain control for the far-field beam of the antenna array on any φ-section using an inseparable Chebyshev matrix. The Chebyshev polynomial is a solution to the Chebyshev differential equation, and its expression is:

[0053]

[0054] The solution is:

[0055]

[0056] For T m From (x0) = R, we can obtain:

[0057]

[0058] In formulas (1)-(3), m is the order of the polynomial, and R is the ratio of the main lobe value to the side lobe value.

[0059] For a traditional Chebyshev matrix distribution, its weighted distribution on the antenna array surface is separable, and the resulting array far-field radiation pattern is equivalent to the superposition of radiation patterns from two linear arrays in mutually perpendicular directions. Therefore, the array can only guarantee that the current distribution in the directions of the two linear arrays conforms to the Chebyshev distribution. However, in radiation pattern sections outside these two directions, since the circuit distribution in the section direction is a vector superposition of the two linear array directions, its directivity will be reduced to a certain extent and will not conform to the Chebyshev distribution with equal sidelobes.

[0060] This implementation uses an inseparable Chebyshev matrix for the inseparable design of the array current distribution, which ensures that the array pattern is in any... The current distribution on the cross-section conforms to the Chebyshev distribution, thereby achieving more perfect beam main and side lobe gain control.

[0061] The current distribution of a non-separable Chebyshev array can be expressed as:

[0062] For an M×M planar array, when M=2N:

[0063]

[0064] When M = 2N + 1:

[0065]

[0066] In formulas (4) and (5), N is any positive integer;

[0067] Based on the array main and side lobe gain control logic obtained from the inseparable Chebyshev matrix, taking a 64×64 element array as an example, when the main lobe gain and side lobe gain are set to arbitrary values, the array's gain is determined according to the difference between the main and side lobe gains. Figure 2 (a) shows the current distribution weighting matrix and as shown in the figure. Figure 2 (b) The far-field patterns of the arrays shown all conform to an inseparable Chebyshev distribution:

[0068] After determining the distribution of the array current weighting matrix by the difference between the main lobe gain and the side lobe gain, the values ​​of the current weighting matrix are increased as a whole to meet the specific main lobe gain requirements based on the specific value of the main lobe gain.

[0069] To verify the effectiveness of the main and side lobe gain control, a 64×64 element array is used as an example. For simplicity in data verification, this implementation method sets the side lobe gain to 0dB and the main lobe gain to 20dB, 30dB, 40dB, 50dB, and 60dB respectively. The program's main and side lobe gain control effect is as follows: Figure 3 As shown;

[0070] As can be seen from the program's implementation, the array pattern conforms to the Chebyshev distribution with equal sidelobes, and the main lobe gain values ​​are 20.0422dB, 30.0422dB, 40.0422dB, 50.0422dB, and 60.0422dB, respectively, while the sidelobe gain controls are 0.0266dB, 0.0266dB, -0.0748dB, -0.5662dB, and 0.0399dB, respectively.

[0071] This invention utilizes an inseparable Chebyshev matrix to regulate the main and side lobe gains of the array far-field beam. Compared to the traditional Chebyshev matrix-based regulation scheme, which can only achieve Chebyshev distribution and corresponding gain control in the horizontal and vertical directions, this invention features a Chebyshev distribution in any cross section along the beam pointing direction while simultaneously ensuring gain control effectiveness.

[0072] S3: The program calls the array topology design lookup database through the submodule. Based on the expected array size, main lobe and side lobe gain and main lobe width, the array cell spacing parameters are obtained by querying the high-dimensional matrix obtained by fitting the linear relationship between the array topology and the corresponding parameters. The array topology design scheme is then obtained and transmitted to the software module.

[0073] Main lobe width control: This implementation method uses a high-dimensional matrix data obtained by linearly fitting the relationship between the array topology and the main lobe width and the main and side lobe gains of the array beam to look up a table, thereby providing a topology design scheme for the array and realizing the main lobe width control.

[0074] This implementation records the original main lobe width data of the array obtained after main and side lobe gain adjustment, and integrates it with array topology data such as array size and element spacing into a high-dimensional matrix. The correspondence between array topology data and main lobe width is supported by a high-dimensional correspondence table through linear fitting. Based on specific settings, the main lobe width of the array pattern can be further controlled on the basis of accurate main and side lobe gain control.

[0075] Based on the relationship between the main lobe width and the array topology, a rough correspondence between the array size and the main lobe width control range can be determined, as shown in Table 1:

[0076] Table 1

[0077] Minimum width 28 12 4 2.2 1.1 0.5 0.2 Maximum width 60 34 20 10 6 3 1.4

[0078] Using a 64×64 array as an example, the accuracy of main lobe width control within the adjustable range of the program is verified. The program's main lobe width control effect is as follows: Figure 4As shown in the program results, when the expected main lobe width is set to 1°, 1.5°, 2°, and 2.5° respectively, the program generates results of 1.2°, 1.6°, 2°, and 2.6°. Therefore, the average control error of the program in the case of a 64×64 array is 7.6%. For other array sizes, from 4×4 to 128×128 arrays, the control errors are 2.6%, 2.5%, 5.2%, 7.6%, and 10.5% respectively. It is evident that as the main lobe width decreases, the program's control accuracy for the main lobe width is somewhat limited.

[0079] S4: Call the antenna array simulation module through the program call submodule to simulate the obtained amplitude-weighted array and array topology design scheme;

[0080] S5: The phase weighting matrix in the design scheme is obtained through the beam pointing control submodule, the phase weighting array generation submodule and the array beam simulation submodule. The corresponding required antenna far-field radiation pattern is output and transmitted to the software module through the simulation parameter output submodule.

[0081] Beam pointing control: In this embodiment, beam pointing control is achieved by performing phase compensation between array elements in both the pitch and horizontal directions. The relationship between the array beam pointing and the phase difference between array elements in a single direction is as follows:

[0082]

[0083] In formula (6), θ is the beam pointing angle. λ is the phase difference between adjacent array elements, λ is the signal wavelength, and d is the spacing between array elements.

[0084] After determining the beam pointing in both the elevation and horizontal directions, the overall beam pointing can be controlled by the vector sum of these two directions. Due to the inherent limitations of the rectangular phased array structure, the far-field pattern of the array will be distorted when the beam pointing exceeds a certain range. Therefore, the scanning range of the array designed in this program is limited to ±30° in both the horizontal and elevation directions. The control effect is as follows:

[0085] When the beam pointing direction is set to horizontal -30°, the control effect is as follows: Figure 5 As shown, when the beam direction is set to 10° horizontally and -20° vertically, the control effect is as follows: Figure 6 As shown in the diagram, the beam pointing control is quite accurate when the beam pointing is controlled in a single direction, either horizontally or in the pitch direction. When the program performs two-dimensional beam pointing control, the error term increases for one-dimensional control, but it remains within an acceptable range overall.

[0086] S6: The software module takes the received amplitude weighting matrix, phase weighting matrix and array topology design scheme as the overall array beam control design scheme and outputs them through the data output submodule.

[0087] In summary, this invention can adjust different array beam parameters according to different array sizes and application requirements, including main lobe width, main lobe gain, side lobe gain, and beam pointing. Furthermore, the simulation accuracy can be adjusted according to different needs to achieve a balance between simulation speed and accuracy requirements. At the same time, this invention can be adapted to various types of array element antennas. By importing the far-field radiation pattern of the corresponding array element antenna, this invention can design a control scheme based on its specific characteristic parameters to adapt to the corresponding array.

[0088] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent substitutions, and improvements made to the above embodiments without departing from the scope of the present invention, based on the technical essence of the present invention and within the spirit and principles of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A phased array radar far-field beamforming system, characterized in that, The structure of the phased array radar far-field beamforming system includes: Amplitude-weighted array generation module, array topology design lookup database, software module, and antenna array simulation module; The software module is used to provide a user input data page and a human-computer interaction page, call different modules, and output the calculation results of the amplitude-weighted array generation module, the array topology design lookup database and the antenna array simulation module as the overall array beam control design scheme. The software module includes a human-computer interface submodule, an input data submodule, a program call submodule, and a data output submodule connected in sequence. The human-computer interface submodule is used for human-computer interaction; The input data submodule is used to receive the expected antenna array performance data input by the user, wherein the expected antenna array performance data includes the expected main lobe width, main lobe gain, side lobe gain and array size. The program calling submodule is used by the amplitude-weighted array generation module, the array topology design lookup database, and the antenna array simulation module to design the overall array beam control scheme. The data output submodule is used to output the overall array beam control design scheme; The amplitude weighting array generation module calculates the amplitude weighting array required for beamforming based on the user input data using an inseparable Chebyshev matrix and transmits it to the software module. The array topology design lookup database, based on the user's requirements for array size, obtains high-dimensional matrix data by linearly fitting the relationship between the array topology and the array beam main lobe width and main and side lobe gains, and then performs a lookup to obtain the array topology design scheme, which is then transmitted to the software module. The antenna array simulation module is used to simulate and verify the topology design scheme of the array. It obtains the phase weighting matrix in the design scheme through the beam pointing control calculation relationship of the phased array, outputs the antenna far-field radiation pattern required by the corresponding scheme, and transmits it to the software module. The antenna array simulation module includes a beam pointing control submodule, a phase weighted array generation submodule, an array beam simulation submodule, and a simulation parameter output submodule connected in sequence. The beam pointing control submodule is used to calculate the phased array beam pointing control relationship. The phase-weighted array generation submodule is used to calculate the phase distribution relationship and, in conjunction with the phased array beam pointing control relationship, calculate the phase-weighted matrix of the array topology design scheme. The array beam simulation submodule is used to calculate the antenna far-field pattern required for the array topology design scheme. The simulation parameter output submodule is used to transmit the phase weighting matrix and antenna far-field pattern to the software module.

2. The phased array radar far-field beamforming system according to claim 1, characterized in that, The amplitude-weighted array generation module, the array topology design lookup table database, and the antenna array simulation module are all bidirectionally connected to the program calling submodule.

3. A phased array radar far-field beamforming method, applied to the phased array radar far-field beamforming system described in any one of claims 1-2, characterized in that, include: Step 1: The user inputs the expected array size, main lobe width, main lobe gain, and side lobe gain through the human-machine interface submodule and the data input submodule; Step 2: Call the amplitude weighted array generation module through the program call submodule. Based on the user input data, calculate the amplitude weighted array required for beamforming using the inseparable Chebyshev matrix and transmit it to the software module. Step 3: The program calls the array topology design lookup database through the submodule. Based on the expected array size, main lobe and side lobe gain and main lobe width, the array cell spacing parameters are obtained by querying the high-dimensional matrix obtained by fitting the linear relationship between the array topology and the corresponding parameters. The array topology design scheme is then obtained and transmitted to the software module. Step 4: Call the antenna array simulation module through the program calling submodule to simulate the obtained amplitude-weighted array and array topology design scheme; Step 5: Obtain the phase weighting matrix in the design scheme through the beam pointing control submodule, phase weighting array generation submodule and array beam simulation submodule, output the corresponding required antenna far-field radiation pattern and transmit it to the software module through the simulation parameter output submodule; Step 6: The software module takes the received amplitude-weighted array, phase-weighted matrix, and array topology design as the overall array beam control design and outputs it through the data output submodule.

Images