A fast calculation method of large-scale array antenna pattern based on subarray decomposition synthesis

Abstract

The application discloses a kind of based on subarray decomposition synthesis large-scale array antenna pattern fast calculation method, belong to antenna technical field, to solve the existing large-scale array antenna pattern calculation, efficiency is low, the problem of high scale-down experiment cost.The application is according to large-scale array antenna layout mode and excitation information and is decomposed into several small-scale subarrays, by calculating the pattern of each subarray and single element, and then the pattern of large-scale array antenna is synthesized.The application effectively realizes the simplified calculation of large-scale array antenna pattern from the perspective of reducing the size of the array, compared with the full-size calculation of large-scale array antenna, the provided method significantly reduces the calculation amount and improves the calculation efficiency, and based on the method, the characteristics of large-scale array antenna pattern can be simulated by a small-scale verification system, thereby reducing the experimental cost and risk, providing a reference for the design, engineering implementation and testing of large-scale array antenna.

Description

Technical Field

[0001] This invention belongs to the field of antenna technology, specifically relating to a method for rapid calculation of radiation patterns of large-scale array antennas based on subarray decomposition and synthesis. Background Technology

[0002] In the design and engineering implementation of array antennas, iterative calculations of radiation characteristics such as radiation patterns are required multiple times. In some cases, scaled-down experiments are also necessary to further optimize the array layout, reduce design risks, and control engineering costs, thereby ensuring that the final design meets technical specifications. However, for large-scale array antennas, the large number of array elements results in stringent computational conditions, low computational efficiency, and even the inability to perform full-size calculations. Scaled-down experiments are complex to set up, and to ensure their effectiveness, the array antenna size often needs to remain constant, leading to high costs. Therefore, it is necessary to study a fast calculation method for the radiation pattern of large-scale array antennas based on subarray decomposition and synthesis. This method reduces the computational load of each iteration of the large-scale array antenna calculation, improves design efficiency, and allows for the construction of a new verification system based on the simplified calculation method to accurately simulate the radiation pattern characteristics of large-scale array antennas.

[0003] The radiation pattern product principle indicates that the radiation pattern of an array antenna is jointly determined by the radiation patterns of the array element antennas and the array factor. However, numerical simulations or theoretical prediction methods, such as those based on current distribution and spatial superposition principles, or those based on aperture impulse response, often perform calculations on the entire array size, obtaining only the array factor and radiation pattern of the entire array. They do not fundamentally simplify the calculation of the array antenna radiation pattern by reducing the array size. Furthermore, when setting up and conducting scaled-down experiments, to ensure geometric and electromagnetic similarity, only the volume of the array antenna is reduced proportionally, while the overall size usually remains unchanged. This results in high additional manufacturing and testing costs.

[0004] In summary, there are currently no relevant theories or methods to simplify the calculation of radiation patterns for large-scale array antennas by reducing the size of the array antenna. Therefore, it is necessary to explore methods to obtain radiation patterns for large-scale array antennas by synthesizing the radiation pattern characteristics of small-scale subarrays. This would fundamentally reduce the computational load of numerical simulations or theoretical predictions, improve computational efficiency, and allow for the construction of new small-scale array verification systems to accurately simulate and obtain the radiation pattern characteristics of large-scale array antennas. This is of great significance for the design and engineering implementation of large-scale array antennas. Summary of the Invention

[0005] (a) Technical problems to be solved This invention aims to solve the technical problems of existing large-scale array antenna pattern calculations being huge, inefficient, difficult to implement at full scale, and costly and risky scaled-down experiments. It provides a simplified calculation method based on small-scale subarray decomposition and synthesis, which balances calculation accuracy and efficiency while reducing the difficulty of experimental verification.

[0006] (II) Technical Solution To address the aforementioned problems, this invention proposes a rapid calculation method for the radiation pattern of a large-scale array antenna based on subarray decomposition and synthesis. The core idea is to decompose the large-scale array antenna into several small-scale subarrays based on the array factor decomposition rules. By calculating the radiation patterns of the subarrays and individual elements, and then synthesizing them according to a specific formula, the original array radiation pattern is obtained, fundamentally reducing the computational scale and improving computational efficiency. The process and steps of this method are as follows: Figure 1 As shown, the details are as follows: S1. Define the layout and excitation information for large-scale array antennas. The aperture surface of the large-scale array antenna is rectangular.

[0007] The large-scale array antenna layout mainly includes the number of array elements, the arrangement method, and the spacing between array elements.

[0008] Massive Array Antennas contain M × N Each array element is arranged at equal intervals along the E-plane. M Arranged at equal intervals in the row and H-plane directions N Column, i.e. M × N (E×H); Regarding the element spacing, the element spacing in the E-plane direction is... dE The spacing between the array elements in the H-plane direction is dH The element spacing is the distance between the centers of the radiating apertures of adjacent elements in the E-plane or H-plane direction.

[0009] The excitation information of the massive MIMO antenna includes the excitation signal, and the phase difference or time delay between each element during beam scanning in the E-plane or H-plane direction. The phase difference is used for time-harmonic mode array antennas, and the time delay is used for ultra-wideband pulsed radiation array antennas.

[0010] All elements of the massive MIMO antenna use the same excitation signal; regarding the phase difference or time delay during beam scanning, when beam scanning is performed in the E-plane direction, the phase difference or time delay between two adjacent rows of elements is... α When beam scanning is performed in the H-plane direction, the phase difference or time delay between two adjacent array elements is: β .

[0011] Based on the layout and excitation information of the aforementioned large-scale array antenna, it is denoted as: M [E:dE,α] × N [H:dH,β] .

[0012] S2. Construct several subarrays based on the layout and excitation information of the large-scale array antenna in S1. The number of subarrays is typically 8, named A. i ( i =1,2,3,…,8).

[0013] The elements of the subarrays are all elements of the large-scale array antenna in S1. The layout and excitation information of each subarray are as follows: The arrangement of subarray A1 is as follows: M - m )×( N - n (E×H), the element spacing is the same as that of the large-scale array antenna in S1, and the phase difference or time delay between elements is also the same as that of the large-scale array antenna. Let A1 be denoted as: ( M - m ) [E:dE,α] ×( N - n ) [H:dH,β] ; Subarray A2 is arranged in a 2×2 (E×H) pattern, with the element spacing along the E-plane being... mdE Phase difference or time delay is mα The spacing between the array elements in the H-plane direction is ndH Phase difference or time delay is nβ Let A2 be denoted as: 2 [E:mdE,mα] ×2 [H:ndH,nβ] ; The arrangement of subarray A3 is as follows: M - m )× n (E×H), the element spacing is consistent with the large-scale array antenna in S1, and the phase difference or time delay between elements is also consistent with the large-scale array antenna. A3 is denoted as: ( M - m ) [E:dE,α] × n [H:dH,β] ; Subarray A4 is arranged in a 2×2 pattern, with the element spacing along the E-plane being [missing information]. mdE Phase difference or time delay is mα The spacing between the array elements in the H-plane direction is ( N - n ) dH The phase difference or time delay is ( N- n ) β Let A4 be denoted as: 2 [E:mdE,mα] ×2 [H: (N-n)dH,(N-n)β] ; The arrangement of subarray A5 is as follows m ×( N - n (E×H), the element spacing is the same as that of the large-scale array antenna in S1, and the phase difference or time delay between elements is also the same as that of the large-scale array antenna. Let A5 be denoted as: m [E:dE,α] ×( N - n ) [H:dH,β] ; The subarray A6 is arranged in a 2×2 (E×H) pattern, and the spacing between the array elements on the E-plane is ( M - m ) dE The phase difference or time delay is ( M - m ) α The spacing between the array elements in the H-plane direction is ndH Phase difference or time delay is nβ Let A6 be denoted as: 2 [E:(M-m)dE, (M-m)α] ×2 [H:ndH,nβ] ; The arrangement of subarray A7 is as follows m × n (E×H), the element spacing is consistent with the large-scale array antenna in S1, and the phase difference or time delay between elements is also consistent with the large-scale array antenna. Let A7 be denoted as... m [E:dE,α] × n [H:dH,β] ; The subarray A8 is arranged in a 2×2 (E×H) pattern, and the spacing between the array elements on the E-plane is ( M - m ) dE The phase difference or time delay is ( M - m ) α The spacing between the array elements in the H-plane direction is ( N - n ) dH The phase difference or time delay is ( N - n ) β Let A8 be denoted as: 2 [E:(M-m)dE, (M-m)α] ×2 [H: (N-n)dH,(N-n)β] .

[0014] in, m and nThe values ​​of are respectively: 1 < m < M, 1 < n < N; Subarrays A2, A4, A6, and A8 are all 2×2 arrays, but the spacing between array elements and the phase difference or time delay between array elements are different.

[0015] Furthermore, when M =2 m , N =2 n When a large-scale array antenna consists of an even number of rows and an even number of columns, in order to reduce the number of subarrays and improve working efficiency, the number of subarrays can be reduced to two, namely A1 and A2. Furthermore, when M =2 m +1, N =2 n That is, when a large-scale array antenna is composed of odd-numbered rows and even-numbered columns, the number of subarrays can be reduced to 4, namely A1, A2, A5, and A6. Similarly, when M =2 m , N =2 n +1 means that when the large-scale array antenna is composed of an even number of rows and an odd number of columns, the number of subarrays can also be reduced to 4, namely A1, A2, A3, and A4. And when M =2 m +1, N =2 n +1 means that when a large-scale array antenna consists of an odd number of rows and columns, it still requires the construction of 8 subarrays.

[0016] In particular, when M =4 m , N =4 n That is, the number of rows of a large-scale array antenna. M Number of columns N When all numbers are multiples of 4, we can first construct two subarrays, namely subarray A9:2. [E:2mdE, 2mα] ×2 [H:2ndH, 2nβ] Subarray A 10 :2 m [E:dE,α] ×2 n [H:dH,β] At this time, subarray A 10 Since both the number of rows and columns are even, to further improve work efficiency, we can continue with A. 10 Then construct a smaller subarray A1: m [E:dE,α] × n [H:dH,β] Subarray A2: 2 [E:mdE,mα] ×2 [H:ndH,nβ] To simplify the calculation of subarray A 10This can significantly reduce the size of the constructed subarray. That is, for this type of array antenna, it can be further decomposed and constructed according to the layout characteristics of the constructed subarray. By analogy, although the number of subarrays increases, the size of the subarray will be significantly reduced and the computational efficiency will be greatly improved.

[0017] S3. Calculate the radiation patterns of each subarray and individual element antennas respectively. The radiation pattern mainly includes the E-plane radiation pattern and the H-plane radiation pattern, and can be a frequency domain radiation pattern or a time domain radiation pattern.

[0018] The single array element antenna mentioned above refers to the array element that constitutes a large-scale array antenna.

[0019] Using the same excitation signal as that of a large-scale array antenna, the radiation patterns of each subarray in S2 are calculated through numerical simulation or prediction methods, and are respectively represented as follows: F i ( θ , The subscripts are consistent with the subscripts of the subarray names in S2. The radiation pattern of a single array element antenna is also calculated. f ( θ , ).

[0020] The aforementioned θ The angle is the pitch angle. The angle refers to the azimuth angle.

[0021] The E-plane pattern is F i ( θ ,π / 2) [ =π / 2，-π / 2≤θ≤π / 2] The H-plane pattern is F i ( θ ,0) [ =0，-π / 2≤θ≤π / 2] .

[0022] S4. Synthesize the large-scale array antenna pattern from the patterns of each subarray and individual array element antennas. The radiation pattern of the large-scale array antenna is consistent with that in S3, mainly including the E-plane radiation pattern and the H-plane radiation pattern.

[0023] The radiation pattern of a large-scale array antenna is obtained by combining the radiation patterns of each subarray and a single antenna calculated in S3. The calculation method for this combination is as follows.

[0024] Furthermore, when M =2 m , N=2 n When a large-scale array antenna consists of an even number of rows and even number of columns, its radiation pattern synthesis calculation method can be simplified to:

[0025] Furthermore, when M =2 m +1, N =2 n When a large-scale array antenna consists of odd-numbered rows and even-numbered columns, its radiation pattern synthesis calculation method can be simplified to:

[0026] Similarly, when M =2 m , N =2 n +1, meaning that when a large-scale array antenna consists of an even number of rows and an odd number of columns, its radiation pattern synthesis calculation method can be simplified to...

[0027] In particular, when M =4 m , N =4 n That is, the number of rows of a large-scale array antenna. M Number of columns N When all are multiples of 4, the method for calculating the composite radiation pattern is as follows:

[0028] The E-plane orientation pattern is as follows: F ( θ The H-plane pattern is (0); F (0, ).

[0029] (III) Beneficial Effects Compared with the prior art, the present invention has the following beneficial effects: 1. The method provided by this invention synthesizes the radiation pattern of a large-scale array antenna by combining the radiation patterns of several small-scale subarrays. Compared with the full-size calculation of the large-scale array antenna, the amount of calculation is significantly reduced and the calculation efficiency is significantly improved.

[0030] 2. The method provided by this invention offers a new approach for experimentally verifying the design results of large-scale array antennas. It sets up a new small-scale array verification system based on the array elements of a large-scale array antenna, eliminating the need to manufacture new antennas and set up scaled-down experiments to obtain the radiation pattern of the large-scale array antenna. Therefore, the cost is lower and the risk is more controllable. Furthermore, even for scaled-down experiments, the scale and cost of the scaled-down experiments can be reduced based on the method provided by this invention.

[0031] 3. The method provided by this invention can be applied to array antennas operating in time-harmonic mode, as well as to the simplified calculation of the radiation pattern characteristics of ultra-wideband time-domain pulse radiation large-scale array antennas, and is applicable to any array element form. Attached Figure Description

[0032] Figure 1 A flowchart illustrating the implementation of the method provided by this invention; Figure 2 The method provided by this invention includes the large-scale array antenna layout and the excitation information during E-plane beam scanning; Figure 3 The method provided by this invention includes the large-scale array antenna layout and the excitation information during H-plane beam scanning; Figure 4 The subarrays A1 and A2 required to be constructed in the method provided by this invention; Figure 5 The subarrays A3 and A4 required to be constructed in the method provided by this invention; Figure 6 The subarrays A5 and A6 required to be constructed in the method provided by this invention; Figure 7 The subarrays A7 and A8 required to be constructed in the method provided by this invention; Figure 8 The array element of the large-scale array antenna in the method embodiment provided by the present invention; Figure 9 The excitation signal waveform of the large-scale array antenna in the method embodiment provided by the present invention; Figure 10 In the method embodiment provided by the present invention, subarray A1 is in Figure 9 Time-domain radiation pattern under pulse excitation (including beam scanning); Figure 11 In the method embodiment provided by the present invention, subarray A2 is in Figure 9 Time-domain radiation pattern under pulse excitation (including beam scanning); Figure 12 The method embodiments provided by the present invention Figure 8 The array element antenna shown is in Figure 9 Temporal radiation pattern under excitation; Figure 13 A comparison of the simplified calculation results (including beam scanning) of the E-plane time-domain radiation pattern of the large-scale array antenna obtained in the method embodiment provided by the present invention. Figure 14 A comparison of the simplified calculation results (including beam scanning) of the H-plane time-domain radiation pattern of the large-scale array antenna obtained in the method embodiment provided by the present invention. Detailed Implementation

[0033] The present invention will now be described and explained in detail with reference to the accompanying drawings.

[0034] This invention provides a fast calculation method for the radiation pattern of a large-scale array antenna based on subarray decomposition and synthesis. The basic principle is as follows: The principle of pattern multiplication in array antennas indicates that the pattern of an array antenna can be obtained by multiplying the pattern of a single element antenna by the array factor. The pattern of a single element antenna varies depending on the antenna structure, while the array factor is independent of the element antennas themselves, depending only on the number of elements and the array layout. Decomposing the array factor reveals that the array factor of a large-scale array antenna is a combination of the array factors of several smaller subarrays. Therefore, the calculation of the array factor of a large-scale array antenna can be transformed into the calculation of the array factors of several smaller subarrays, significantly reducing the computational load and resource consumption, thus simplifying the calculation. In actual calculations, the pattern of the subarrays is usually obtained. Therefore, it is necessary to calculate the pattern of a single element antenna, obtain the array factor of the subarray according to the pattern multiplication principle, synthesize the array factors of the large-scale array antenna from the array factors of each subarray, and finally obtain the pattern of the large-scale array antenna from the known array factor of the large-scale array antenna and the pattern of a single element antenna.

[0035] The above mainly applies to the case of in-phase and in-amplitude excitation. When the array antenna operates in beam scanning mode, there is still a phase difference between the array elements. According to the expression for the array factor, the influence of the phase difference on the array factor is the same as the influence of the array antenna layout and element spacing. Therefore, the radiation pattern of a large-scale array antenna in beam scanning mode can still be obtained according to the above conditions. In addition, when the large-scale array antenna is a time-domain pulse radiation array antenna, there is a time delay between the elements. According to the Fourier transform, the time delay in the time domain is exactly the phase change in the frequency domain. Therefore, the above principle can also be applied to the simplified calculation of the time-domain radiation pattern of a large-scale time-domain pulse radiation array antenna.

[0036] In summary, the core technology of this invention lies in simplifying the calculation of large-scale array antenna radiation patterns into the calculation of several small-scale subarray radiation patterns and individual array element radiation patterns, based on the decomposition results and rules of array antenna factors, thereby significantly improving computational efficiency and reducing the demand for computational resources. Figure 1 A flowchart of the method provided by the present invention is given.

[0037] Specifically, the technical solution of the present invention includes the following steps: S1. Define the layout and excitation information of the large-scale array antenna. like Figure 2 ,3 As shown, the large-scale array antenna has a rectangular radiating aperture, and the entire array antenna consists of... M × N It consists of several array elements, which are evenly spaced along the E-plane direction. M Arranged at equal intervals in the row and H-plane directions N The array, or the arrangement of the antennas in the array, is as follows: M × N (E×H); Regarding the element spacing, the element spacing in the E-plane direction is... dE The spacing between the array elements in the H-plane direction is dH The element spacing is the distance between the centers of the radiation apertures of adjacent elements in the E-plane or H-plane direction; when beam scanning is performed, there is also a phase difference or time delay between the elements, such as... Figure 2 As shown, when performing beam scanning in the E-plane direction, the phase difference or time delay between two adjacent rows of array elements is: α ,like Figure 3 As shown, when performing beam scanning in the H-plane direction, the phase difference or time delay between two adjacent array elements on the left and right is... β The phase difference mentioned above is mainly used for narrowband array antennas, and the time delay can be used for narrowband array antennas or time-domain pulse radiation array antennas.

[0038] Based on the above layout and excitation information, the large-scale array antenna is denoted as... M [E:dE,α] × N [H:dH,β] .

[0039] S2. Construct several subarrays based on the layout and excitation information of the large-scale array antenna in S1. Based on the array elements of the large-scale array antenna in S1, eight subarrays are constructed and named A. i ( i =1,2,3,…,8).

[0040] The number of elements, layout, element spacing, and phase difference or time delay of each subarray are as follows: Subarray A1: ( M - m ) [E:dE,α] ×( N - n ) [H:dH,β] Subarray A2: 2 [E:mdE,mα] ×2 [H:ndH,nβ] ; Subarray A3: ( M - m ) [E:dE,α] × n [H:dH,β] Subarray A4: 2 [E:mdE,mα] ×2[H: (N-n)dH,(N-n)β] ; Subarray A5: m [E:dE,α] ×( N - n ) [H:dH,β] Subarray A6: 2 [E:(M-m)dE, (M-m)α] ×2 [H:ndH,nβ] ; Subarray A7: m [E:dE,α] × n [H:dH,β] Subarray A8: 2 [E:(M-m)dE, (M-m)α] ×2 [H: (N-n)dH,(N-n)β] .

[0041] The above subarrays are as follows Figure 4 , 5 As shown in Figures 6 and 7, the element spacing, phase difference, or time delay between elements in subarrays A1, A3, A5, and A7 are consistent with those of a large-scale array antenna. Subarrays A2, A4, A6, and A8 are all 2×2 arrays, but the element spacing is increased by a certain multiple compared to a large-scale array antenna, and the phase difference or time delay between elements is also increased by a corresponding multiple based on the phase difference or time delay of the large-scale array antenna. Subarray A2: The spacing between array elements in the E-plane direction is mdE Phase difference or time delay is mα The spacing between the array elements in the H-plane direction is ndH Phase difference or time delay is nβ ; Subarray A4: The spacing between array elements in the E-plane direction is mdE Phase difference or time delay is mα The spacing between the array elements in the H-plane direction is ( N - n ) dH The phase difference or time delay is ( N - n ) β ; Subarray A6: The spacing between array elements in the E-plane direction is ( M - m ) dE The phase difference or time delay is ( M - m ) α The spacing between the array elements in the H-plane direction is ndH Phase difference or time delay is nβ ; Subarray A8: The spacing between array elements in the E-plane direction is ( M - m ) dE The phase difference or time delay is ( M -m ) α The spacing between the array elements in the H-plane direction is ( N - n ) dH The phase difference or time delay is ( N - n ) β .

[0042] In the above construction process, 1 < m < M ,1< n < N .

[0043] Furthermore, when M =2 m , N =2 n When a large-scale array antenna consists of an even number of rows and an even number of columns, in order to reduce the number of subarrays and improve working efficiency, the number of subarrays can be reduced to two, namely A1 and A2. That is, at this time, subarrays A1, A3, A5, and A7 are the same, and subarrays A2, A4, A6, and A8 are the same. when M =2 m +1, N =2 n When a large-scale array antenna is composed of odd-numbered rows and even-numbered columns, the number of subarrays can be reduced to 4, namely A1, A2, A5, and A6. That is, at this time, subarrays A1 and A3 are the same, subarrays A2 and A4 are the same, subarrays A5 and A7 are the same, and subarrays A6 and A8 are the same. Similarly, when M =2 m , N =2 n +1 means that when the large-scale array antenna is composed of an even number of rows and an odd number of columns, the number of subarrays can also be reduced to 4, namely A1, A2, A3, and A4. That is, at this time, subarrays A1 and A5 are the same, A2 and A6 are the same, subarrays A3 and A7 are the same, and subarrays A4 and A8 are the same. And when M =2 m +1, N =2 n +1 means that when a large-scale array antenna consists of an odd number of rows and columns, it still requires the construction of 8 subarrays.

[0044] In particular, when M =4 m , N =4 n That is, the number of rows of a large-scale array antenna. M Number of columns N When all numbers are multiples of 4, we can first construct two subarrays, namely subarray A9:2.[E:2mdE, 2mα] ×2 [H:2ndH, 2nβ] Subarray A 10 :2 m [E:dE,α] ×2 n [H:dH,β] At this time, subarray A 10 Since both the number of rows and columns are even, to further improve work efficiency, we can continue with A. 10 Then construct a smaller subarray A1: m [E:dE,α] × n [H:dH,β] Subarray A2: 2 [E:mdE,mα] ×2 [H:ndH,nβ] To simplify the calculation of subarray A 10 This is equivalent to constructing a total of 3 subarrays: A9, A1, and A2. However, the largest subarray, A1, is smaller than the initial subarray A. 10 The size is reduced by a quarter. That is, for this type of array antenna, an even number of rows and columns of subarrays can be constructed first, and then the subarrays can be decomposed and constructed again, and so on. Although the number of subarrays increases, the size will be significantly reduced and the computational efficiency will be greatly improved.

[0045] S3. Calculate the radiation patterns of each subarray and individual element antennas respectively. Radiation patterns mainly include E-plane and H-plane radiation patterns, and can be in the frequency domain or time domain. The E-plane radiation pattern typically corresponds to the azimuth angle. φ =π / 2; the H-plane orientation pattern usually corresponds to the azimuth angle. φ The result when =0.

[0046] Using the same excitation signal as large-scale array antennas, such as Figure 9 As shown, the radiation patterns of each subarray in S2 under synchronous excitation and beam scanning conditions are calculated using numerical simulation or prediction methods, respectively. Figure 10 , Figure 11 As shown, and respectively represented as F i ( θ , φ The subscripts are consistent with the subscripts of the subarray names in S2. The radiation pattern of a single array element antenna is also calculated. f ( θ , φ )like Figure 12 As shown, this single element antenna is an element that constitutes a large-scale array antenna. A typical element antenna is as follows: Figure 8 As shown.

[0047] S4. Synthesize the large-scale array antenna pattern from the patterns of each subarray and individual array element antennas. The radiation pattern of a large-scale array antenna is obtained by combining the radiation patterns of each subarray calculated in S3 and the radiation patterns of individual array element antennas. The calculation method for the synthesis is as follows.

[0048] Furthermore, when M =2 m , N =2 n When a large-scale array antenna consists of an even number of rows and even number of columns, its radiation pattern synthesis calculation method can be simplified to:

[0049] Furthermore, when M =2 m +1, N =2 n When a large-scale array antenna consists of odd-numbered rows and even-numbered columns, its radiation pattern synthesis calculation method can be simplified to:

[0050] Similarly, when M =2 m , N =2 n +1, meaning that when a large-scale array antenna consists of an even number of rows and an odd number of columns, its radiation pattern synthesis calculation method can be simplified to...

[0051] In particular, when M =4 m , N =4 n That is, the number of rows of a large-scale array antenna. M Number of columns N When all are multiples of 4, the method for calculating the composite pattern is as follows:

[0052] The radiation pattern of the massive MIMO antenna in S1 is obtained by simplifying the calculation using the above method, and can be compared with the radiation pattern of the massive MIMO antenna obtained directly using numerical simulation or prediction methods, such as... Figure 13 , Figure 14 As shown. This completes the simplified calculation of the radiation pattern for a large-scale array antenna.

[0053] In summary, in order to significantly maximize the effectiveness of the method provided by this invention, the layout characteristics of large-scale array antennas can be analyzed and considered in S1 and S2 to minimize the number of subarrays or the size of each subarray, thereby significantly improving computational efficiency.

[0054] The above content has described and explained the basic principles and key problem-solving ideas of the method provided by the present invention. In order to better describe the method and implementation process provided by the present invention, the following embodiments are given, and a more detailed demonstration and further explanation are given below in conjunction with the accompanying drawings.

[0055] Example In this embodiment, the array element of the large-scale array antenna whose radiation pattern is to be calculated is a Vivaldi antenna, such as... Figure 8 As shown, the antenna dimensions are 297 mm × 210 mm, consistent with the size of an A4 sheet of paper, with the radiation direction pointing towards the shorter side. The array antenna is arranged in an 8 × 14 (E × H) configuration. M =8、 N =14, such as Figure 2 , 3 As shown, there are 8 rows in the E-plane direction, and the spacing between adjacent array elements is... dE =220 mm, with 14 columns in the H-plane direction, and the spacing between adjacent array elements is... dH =180 mm. The array antenna is in time-domain pulse radiation mode, and the excitation waveform of each element is consistent, all being zero-order Gaussian pulses with a pulse width of 0.6 ns, such as Figure 9 As shown.

[0056] When the array antennas are synchronously excited Figure 2 , 3 The time delay Δ shown φ E =Δ φ H =0 ns; When beam scanning is performed on the E-plane, the time delays corresponding to scanning angles of 10°, 20°, and 30° are respectively Δ φ E = α =0.127 ns, 0.251 ns, 0.367 ns; when performing beam scanning in the H-plane, the time delays corresponding to scanning angles of 10°, 20°, and 30° are respectively Δ φ H = β =0.104 ns, 0.205 ns, 0.300 ns.

[0057] The above describes the layout and excitation information of the large-scale array antenna whose radiation pattern is to be calculated.

[0058] like Figure 1 As shown, according to the simplified calculation method provided by the present invention, the layout of the large-scale array antenna is first analyzed, and its number of rows ( M =8) and column number ( NSince all numbers (=14) are even, only two subarrays are needed to simplify the calculation of their radiation patterns. Let m = M / 2=4, n = N / 2=7, the two subarrays are subarray A1 and subarray A2, as follows Figure 4 As shown, the elements of these two subarrays are consistent with those of a large-scale array antenna. Subarray A1 has a 4-element layout. [E:dE,α] ×7 [H:dH,β] That is, the element spacing and time delay between elements of this subarray are consistent with those of a large-scale array antenna; the layout of subarray A2 is 2 [E: 4dE, 4α] ×2 [H: 7dH, 7β] That is, the spacing between the array elements in the E-plane direction is 4. dE The time delay is 4 α The spacing between the array elements in the H-plane direction is 7. dH The time delay is 7 β .

[0059] like Figure 1 As shown, after the construction is completed, numerical simulations are used to calculate the E-plane and H-plane radiation patterns of subarrays A1 and A2 during synchronous excitation and beam scanning, respectively. Figure 10 , 11 As shown, the E-plane and H-plane radiation patterns of a single array element antenna are calculated simultaneously, as follows: Figure 12 As shown.

[0060] Based on the calculated results, the radiation patterns of the large-scale array antenna are synthesized according to the method provided in this invention, thereby obtaining the E-plane and H-plane radiation patterns. These patterns are then compared with the full-scale numerical simulation results of the large-scale array antenna. Figure 13 , 14 As shown in the comparison chart, the two results match well. The table below presents a comparison of the quantization results of the 3 dB beamwidth of the large-scale array antenna under synchronous excitation and different beam scanning angles.

[0061]

[0062] Comparing the quantization results of 3 dB beamwidth, the simplified calculation method provided by this invention has a deviation of less than 3% compared to the full-size numerical simulation results of large-scale array antennas. Furthermore, the method provided by this invention only requires two small-scale subarrays to complete the calculation, demonstrating the effectiveness of this invention.

[0063] The above description, in conjunction with specific embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the inventive concept, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for fast calculation of radiation patterns of large-scale array antennas based on subarray decomposition and synthesis, characterized in that, Includes the following steps: S1 specifies the layout and excitation information for large-scale array antennas: The large-scale array antenna has a rectangular aperture and contains M×N array elements. The elements are arranged in M ​​rows at equal intervals along the E-plane and N columns at equal intervals along the H-plane. The element spacing along the E-plane and H-plane is as follows: dE , dH ; All elements of the massive MIMO antenna use the same excitation signal. When performing beam scanning in the E-plane or H-plane direction, the phase difference or time delay between adjacent elements are respectively... α , β ; Let the above large-scale array antenna be denoted as A: M [E:dE,α] × N [H:dH,β] ; S2 constructs eight subarrays based on the large-scale array antenna layout and excitation information: Subarray A1 contains ( M - m )×( N - n ) array elements, with the same element spacing and excitation information as A, denoted as A1: ( M - m ) [E:dE,α] ×( N - n ) [H:dH,β] Subarray A2 contains a total of 2×2 array elements, and the spacing between array elements in the E-plane direction is... mdE Phase difference or time delay is mα The spacing between the array elements in the H-plane direction is ndH Phase difference or time delay is nβ Let A2 be denoted as: 2 [E:mdE,mα] ×2 [H:ndH,nβ] ; Subarray A3 contains ( M - m )× n Each array element has the same element spacing and excitation information as A. Let A3 be denoted as: ( M - m ) [E:dE,α] × n [H:dH,β] Subarray A4 contains a total of 2×2 array elements, and the element spacing in the E-plane direction is... mdE Phase difference or time delay is mα The spacing between the array elements in the H-plane direction is ( N - n ) dH Phase difference or time delay is ( N - n ) β Let A4 be denoted as: 2 [E:mdE,mα] ×2 [H: (N-n)dH,(N-n)β] ; Subarray A5 contains a total of m ×( N - n A5 consists of 10 array elements, with the same element spacing and excitation information as A. Let A5 be denoted as: m [E:dE,α] ×( N - n ) [H:dH,β] Subarray A6 contains 2×2 array elements, and the spacing between array elements in the E-plane direction is ( M - m ) dE Phase difference or time delay is ( M - m ) α The spacing between the array elements in the H-plane direction is ndH Phase difference or time delay is nβ Let A6 be denoted as: 2 [E:(M-m)dE, (M-m)α] ×2 [H:ndH,nβ] ; Subarray A7 contains a total of m × n Each array element has the same element spacing and excitation information as A. Let A7 be denoted as... m [E:dE,α] × n [H:dH,β] Subarray A8 contains a total of 2×2 array elements, and the spacing between array elements in the E-plane direction is ( M - m ) dE Phase difference or time delay is ( M - m ) α The spacing between the array elements in the H-plane direction is ( N - n ) dH Phase difference or time delay is ( N - n ) β Let A8 be denoted as: 2 [E:(M-m)dE, (M-m)α] ×2 [H: (N-n)dH,(N-n)β] . S3 calculates the radiation patterns of each subarray and individual array element antenna respectively: The calculated radiation patterns of each subarray are respectively represented as follows: F i ( θ , Meanwhile, the radiation pattern of a single array element antenna was calculated as follows: f ( θ , ). S4 synthesizes the large-scale array antenna pattern from the antenna patterns of each subarray and individual array element: The calculation method for synthesizing the radiation patterns of a large-scale array antenna from the radiation patterns of each subarray and individual array element antennas is as follows: .

2. The method for fast calculation of large-scale array antenna radiation patterns based on subarray decomposition and synthesis according to claim 1, characterized in that, The range of values ​​for m is 1 < m < M, and the range of values ​​for n is 1 < n < N.

3. The method for fast calculation of large-scale array antenna radiation patterns based on subarray decomposition and synthesis according to claim 1, characterized in that, when M =2 m , N =2 n When a large-scale array antenna consists of an even number of rows and columns, its radiation pattern synthesis calculation method can be simplified to... .

4. The method for fast calculation of large-scale array antenna radiation patterns based on subarray decomposition and synthesis according to claim 1, characterized in that, when M =2 m +1, N =2 n When a large-scale array antenna consists of odd-numbered rows and even-numbered columns, its radiation pattern synthesis calculation method can be simplified to... .

5. The method for fast calculation of large-scale array antenna radiation patterns based on subarray decomposition and synthesis according to claim 1, characterized in that, when M =2 m , N =2 n +1, meaning that when a large-scale array antenna consists of an even number of rows and an odd number of columns, its radiation pattern synthesis calculation method can be simplified to... .

6. The method for fast calculation of large-scale array antenna radiation patterns based on subarray decomposition and synthesis according to claim 1, characterized in that, when M =4 m , N =4 n That is, the number of rows of a large-scale array antenna. M Number of columns N When all are multiples of 4, the method for calculating the composite pattern is as follows: .

7. The method for fast calculation of large-scale array antenna radiation patterns based on subarray decomposition and synthesis according to claim 1, characterized in that, The radiation pattern includes a frequency domain radiation pattern or a time domain radiation pattern, which is applicable to both time-harmonic mode array antennas and ultra-wideband time-domain pulse radiation array antennas.

8. The method according to claim 1, characterized in that, The phase differences α and β are used for the time-harmonic mode array antenna, and the time delay α and β For use in ultra-wideband time-domain pulse radiation array antennas.

9. The method according to claim 1, characterized in that, In step S3, the radiation patterns of each subarray and individual array elements are calculated using numerical simulation or theoretical prediction methods.

10. The method according to claim 1, characterized in that, The element spacing mentioned in step S1 dE and dH The distance between the centers of the radiating apertures of adjacent array elements; the radiation pattern includes the E-plane radiation pattern (corresponding to...). =π / 2) and H-plane radiation pattern (corresponding to =0).

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