Irregular antenna subarrays, phased array antennas, and design methods for phased array antennas

Abstract

The present invention provides an irregular antenna subarray, a phased array antenna, and a design method for a phased array antenna. The irregular antenna subarray includes: a plurality of antenna units arranged in a matrix form, each row and each column of the matrix includes at least two antenna units, and the distance between any two adjacent antenna units is equal; at least one radio frequency interface is provided on the matrix plane, each radio frequency interface corresponds to an antenna combination consisting of any four adjacent antenna units arranged in a matrix form, the radio frequency interface is located at the center point of the four adjacent antenna units arranged in a matrix form in the corresponding antenna combination, the radio frequency interface is equidistant from the four adjacent antenna units arranged in a matrix form and is connected to any one of the antenna units; for any antenna unit, it is connected to at most one radio frequency interface, and it belongs to at least one antenna combination with a corresponding radio frequency interface. The phased array antenna composed of the irregular antenna subarray provided by the present invention can effectively improve the sidelobe suppression level.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to an irregular antenna subarray, a phased array antenna, and a design method for the phased array antenna. Background Art

[0002] In recent years, the rapid development of active phased array antenna technology, characterized by high power and high efficiency, has provided an effective technical approach for significantly increasing radar range. This has significantly improved antenna systems in terms of reliability, stealth, anti-interference capabilities, and multi-target tracking capabilities. Existing phased array antennas can reduce sidelobe levels by thinning the arrays into smaller units. While this approach offers the greatest advantage of reduced complexity and cost, it struggles to achieve optimal results in scenarios with high sidelobe requirements. Summary of the Invention

[0003] Embodiments of the present invention provide an irregular antenna subarray, a phased array antenna, and a design method for a phased array antenna to address the problems in the prior art of sparsely distributing phased array antennas based on subarrays, such as low sidelobe suppression and inflexible subarray sparse distribution.

[0004] In a first aspect, an embodiment of the present invention provides an irregular antenna subarray, including:

[0005] multiple antenna units;

[0006] The multiple antenna units are arranged in a matrix form, each row and each column of the matrix includes at least two antenna units, and the distance between any two adjacent antenna units is equal;

[0007] At least one RF interface is also provided on the matrix plane, each RF interface corresponds to an antenna combination, the antenna combination is composed of any four adjacent antenna units arranged in a matrix form, the RF interface is located at the center point of the four adjacent antenna units arranged in a matrix form in the corresponding antenna combination, the RF interface is equidistant from the four adjacent antenna units arranged in a matrix form and is connected to any one of the four adjacent antenna units arranged in a matrix form; and, for any antenna unit, the antenna unit is connected to at most one RF interface, and the antenna unit belongs to at least one target antenna combination, and the target antenna combination is an antenna combination having a corresponding RF interface.

[0008] In a second aspect, an embodiment of the present invention provides a phased array antenna, wherein the phased array antenna is composed of a plurality of basic regular antenna sub-arrays and a plurality of irregular antenna sub-arrays as described in the first aspect above;

[0009] Among them, the basic regular antenna subarray includes multiple antenna units arranged in a matrix form, and each antenna unit is correspondingly connected to a radio frequency interface; the multiple basic regular antenna subarrays are fully distributed in the middle position of the phased array antenna surface, and the multiple irregular antenna subarrays are sparsely distributed at the edge positions of the phased array antenna surface.

[0010] In a possible implementation, a distance between any two adjacent antenna units in the irregular antenna subarray is the same as a distance between any two adjacent antenna units in the basic regular antenna subarray.

[0011] In a possible implementation manner, the irregular antenna subarray and the basic regular antenna subarray have the same number of radio frequency interfaces.

[0012] In a possible implementation, the irregular antenna subarray is divided into different types according to different antenna units connected to each radio frequency interface in the irregular antenna subarray;

[0013] The number of types of the irregular antenna sub-arrays in the phased array antenna does not exceed a preset value.

[0014] In a possible implementation, the basic regular antenna subarray is a 2×2 subarray formed by 4 antenna units arranged in a matrix form, and the irregular antenna subarray is a 3×3 subarray formed by 9 antenna units arranged in a matrix form.

[0015] In a possible implementation, the number of the irregular antenna subarrays is 48, and the number of the basic regular antenna subarrays is 72.

[0016] In a third aspect, an embodiment of the present invention provides a method for designing a phased array antenna, the method being used to generate the phased array antenna as described in the second aspect or any possible implementation of the second aspect;

[0017] The method comprises:

[0018] The positions of the basic regular antenna subarrays, the irregular antenna subarrays, and the positions of the antenna units connected to the radio frequency interface in each irregular antenna subarray are used as optimization variables. The optimal values of each of the optimization variables are found through an optimization algorithm to obtain the phased array antenna.

[0019] In a possible implementation, the optimization algorithm is a genetic algorithm, and finding the optimal value of each optimization variable by the genetic algorithm includes:

[0020] Setting parameters for a genetic algorithm and generating an initial population; wherein each individual in the initial population is a set of optimization variables, and each set of optimization variables includes a position of a basic regular antenna subarray, a position of an irregular antenna subarray, and a position of an antenna unit connected to a radio frequency interface in each irregular antenna subarray;

[0021] Calculate the fitness value corresponding to each individual and determine the individual corresponding to the maximum fitness value;

[0022] Selecting, crossing over, and mutating individuals in the initial population to generate a new population;

[0023] Calculate the fitness value corresponding to each individual in the new population, and update the individual corresponding to the maximum fitness value, and iterate continuously until the maximum number of iterations is reached;

[0024] The optimal value of each optimization variable is determined according to the individual corresponding to the maximum fitness value.

[0025] In a possible implementation, the formula for calculating the fitness value corresponding to each individual in the new population is:

[0026] y=abs(MSLL)

[0027]

[0028]

[0029]

[0030]

[0031] Wherein, y is the formula for calculating the fitness value corresponding to each individual in the new population, abs represents the absolute value function, MSLL is the maximum sidelobe level of the elevation projection pattern, S represents θ=θ0, The sidelobe interval of the elevation projection pattern, ψ0 represents half the main lobe width, F theta (θ) is the elevation projection pattern function of the phased array antenna surface, is the radiation pattern function of the phased array antenna, N1 and N2 represent the number of basic regular antenna subarrays and the number of irregular antenna subarrays in the phased array antenna, respectively. xi d yi They represent the horizontal and vertical coordinates of each antenna unit when the plane rectangular coordinate system is established with the center of the phased array antenna as the origin. represents the unit field, j is the unit of the imaginary part of the complex number, k is the wave number corresponding to the operating frequency of the phased array antenna, Indicates the beam pointing angle.

[0032] An embodiment of the present invention provides an irregular antenna subarray, which includes multiple antenna units; the multiple antenna units are arranged in a matrix form, each row and each column of the matrix includes at least two antenna units, and the distance between any two adjacent antenna units is equal; at least one radio frequency interface is also provided on the matrix plane, each radio frequency interface corresponds to an antenna combination, the antenna combination is composed of any four adjacent antenna units arranged in a matrix form, the radio frequency interface is located at the center point of the four adjacent antenna units arranged in a matrix form in the corresponding antenna combination, the radio frequency interface is equidistant from the four adjacent antenna units arranged in a matrix form and is connected to any one of the four adjacent antenna units arranged in a matrix form; and for any antenna unit, the antenna unit is connected to at most one radio frequency interface, and the antenna unit belongs to at least one target antenna combination, and the target antenna combination is an antenna combination having a corresponding radio frequency interface. The phased array antenna composed of irregular antenna subarrays provided by the embodiment of the present invention can realize the sparse distribution of the phased array antenna based on the subarray as a unit and the sparse distribution of the phased array antenna based on the antenna as a unit, which can increase the degree of freedom of antenna unit optimization and effectively improve the sidelobe suppression level. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 Schematic diagram of a typical 4-element AiP package provided by an embodiment of the present invention;

[0035] Figure 2 This is an example diagram of the array plane of a phased array antenna constructed with 4 array elements AiP provided in an embodiment of the present invention;

[0036] Figure 3 : This is a simulated radiation pattern of a phased array antenna constructed with 4 array elements AiP provided in an embodiment of the present invention;

[0037] Figure 4 This is an example diagram of an array plane of a phased array antenna provided by an embodiment of the present invention;

[0038] Figure 5 This is an example diagram of an array plane of a phased array antenna provided by an embodiment of the present invention;

[0039] Figure 6 This is a schematic diagram illustrating a type of irregular antenna subarray provided by an embodiment of the present invention;

[0040] Figure 7 This is an example diagram of an array plane of a phased array antenna provided by an embodiment of the present invention;

[0041] Figure 8 is a simulated radiation pattern of a phased array antenna provided by an embodiment of the present invention;

[0042] Figure 9 This is a schematic diagram illustrating a type of irregular antenna subarray provided by an embodiment of the present invention;

[0043] Figure 10 This is a schematic diagram illustrating a type of irregular antenna subarray provided by an embodiment of the present invention;

[0044] Figure 11 This is a flowchart of an implementation method for designing a phased array antenna provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In the following description, specific details such as particular system structures and techniques are provided for purposes of illustration, not limitation, to facilitate a thorough understanding of the embodiments of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

[0046] In order to make the purpose, technical solutions and advantages of the present invention more clear, specific embodiments will be described below with reference to the accompanying drawings.

[0047] Taking the AiP subarray as an example, for an AiP (Antenna in Package) module containing multiple antennas, a single module is regarded as a subarray. Figure 1 A typical 4-element AiP packaging diagram provided in an embodiment of the present invention is shown in FIG. Figure 1 As shown, the antenna units in each module are usually arranged in a regular rectangular pattern, with the antenna spacing slightly larger than half a wavelength (depending on the required grating-free scanning angle). In this form, AiP sub-arrays are used to form a larger-scale phased array, which is generally arranged in a regular rectangular pattern. Figure 2 An example diagram of the array plane of a phased array antenna constructed with 4 array elements AiP provided in an embodiment of the present invention is shown in FIG. Figure 2 As shown, the phased array antenna is composed of 4 array elements AiP rectangular array, Figure 3 The simulated radiation pattern of the phased array antenna constructed by the 4-element AiP provided in the embodiment of the present invention is as follows: Figure 3 As shown, the sidelobe suppression level of the phased array antenna is about 13dB. The main object of the present invention is to propose an array method based on sub-array AiP with better sidelobe suppression capability.

[0048] Figure 4 This is an example diagram of a phased array antenna provided in an embodiment of the present invention. In the prior art, if there is a higher requirement for sidelobe suppression, the following can be used: Figure 4 The phased array antenna shown here uses a tangential array configuration to improve sidelobe suppression. If sidelobe suppression still fails to meet requirements, antenna synthesis can be performed based on specifications, using amplitude weighting to reduce sidelobe suppression to the required level. Amplitude weighting is typically implemented using a digitally controlled attenuator within the TR, a common beamforming method used in receiving phased arrays.

[0049] For the transmitting phased array, since we do not want to waste precious transmitting power, we can suppress the side lobes by optimizing the antenna sparse distribution. Figure 5 An example diagram of a phased array antenna provided in an embodiment of the present invention is shown in FIG. Figure 5 As shown in the figure, this method can not only suppress the side lobes, but also reduce the hardware cost of the phased array by reducing the number of channels. Figure 5 They can be placed inside a regular grid or randomly arranged through optimization.

[0050] although Figure 5 The array arrangement shown in [1] has the advantage of not wasting any TR channels. However, it can only be thinned out in subarray units, rather than arbitrarily thinning out each antenna. This constraint results in suboptimal optimization, making it difficult to achieve the optimization goal in scenarios with high sidelobe requirements.

[0051] Based on this, an embodiment of the present invention provides an irregular antenna subarray, which includes: multiple antenna units.

[0052] The multiple antenna units are arranged in a matrix form, each row and each column of the matrix includes at least two antenna units, and the distance between any two adjacent antenna units is equal.

[0053] At least one RF interface is also provided on the matrix plane, each RF interface corresponds to an antenna combination, the antenna combination is composed of any four adjacent antenna units arranged in a matrix form, the RF interface is located at the center point of the four adjacent antenna units arranged in a matrix form in the corresponding antenna combination, the distance between the RF interface and the four adjacent antenna units arranged in a matrix form is equal and is connected to any one of the four adjacent antenna units arranged in a matrix form; and, for any antenna unit, the antenna unit is connected to at most one RF interface, and the antenna unit belongs to at least one target antenna combination, and the target antenna combination is an antenna combination with a corresponding RF interface.

[0054] In this embodiment, the following specific implementation examples are used only to illustrate the construction principle of the irregular antenna subarray, but not to limit the irregular antenna subarray. Figure 6The schematic diagram of a class of irregular antenna subarrays provided by the embodiment of the present invention is as follows: Figure 6 As shown, Figure 6 5 types of 9-choose-4 irregular antenna subarrays are shown. The irregular antenna subarray includes 9 antenna units, including 4 active antenna units (active antenna units are antenna units connected to the radio frequency interface) and 5 parasitic antenna units (parasitic antenna units are antenna units not connected to the radio frequency interface, that is, non-active antenna units, in Figure 6 Indicated by blank cells; in the actual design of an irregular antenna subarray, the non-active antenna unit can exist in the form of a parasitic antenna unit; or the non-active antenna can be directly removed, leaving only the active antenna. ), the 9 antenna units are arranged in a matrix, with each row and column of the matrix including 3 antenna units, and the distance between any two adjacent antenna units is equal. Four RF interfaces are provided on the matrix plane, each corresponding to an antenna combination consisting of any 4 adjacent antenna units arranged in a matrix. The RF interface is located at the center point of the 4 adjacent antenna units arranged in a matrix in the corresponding antenna combination. The RF interface is equidistant from the 4 adjacent antenna units arranged in a matrix and is connected to any one of the 4 adjacent antenna units arranged in a matrix. For any antenna unit in the irregular antenna subarray, the antenna unit is connected to at most one RF interface, and the antenna unit belongs to at least one antenna combination with a corresponding RF interface.

[0055] In this embodiment, to ensure that the RF interface in an irregular antenna subarray satisfies the equal-phase condition to its four adjacent antenna elements arranged in a matrix, the distance between any two adjacent antenna elements in the irregular antenna subarray is equal. Furthermore, under the equal-phase constraint, multiple irregular antenna subarrays can be derived. A phased array antenna composed of multiple irregular antenna subarrays can achieve sparse distribution of the phased array antenna based on subarrays or antenna elements, effectively improving the degree of freedom of antenna element optimization and sidelobe suppression capabilities.

[0056] An embodiment of the present invention provides an irregular antenna subarray, which includes multiple antenna units; the multiple antenna units are arranged in a matrix form, each row and each column of the matrix includes at least two antenna units, and the distance between any two adjacent antenna units is equal; at least one radio frequency interface is also provided on the matrix plane, each radio frequency interface corresponds to an antenna combination, the antenna combination is composed of any four adjacent antenna units arranged in a matrix form, the radio frequency interface is located at the center point of the four adjacent antenna units arranged in a matrix form in the corresponding antenna combination, the radio frequency interface is equidistant from the four adjacent antenna units arranged in a matrix form and is connected to any one of the four adjacent antenna units arranged in a matrix form; and for any antenna unit, the antenna unit is connected to at most one radio frequency interface, and the antenna unit belongs to at least one target antenna combination, and the target antenna combination is an antenna combination having a corresponding radio frequency interface. The phased array antenna composed of irregular antenna subarrays provided by the embodiment of the present invention can realize the sparse distribution of the phased array antenna based on the subarray as a unit and the sparse distribution of the phased array antenna based on the antenna as a unit, which can increase the degree of freedom of antenna unit optimization and effectively improve the sidelobe suppression level.

[0057] An embodiment of the present invention provides a phased array antenna. The phased array antenna is composed of a plurality of basic regular antenna sub-arrays and a plurality of irregular antenna sub-arrays.

[0058] Among them, the basic regular antenna subarray includes multiple antenna units arranged in a matrix form, and each antenna unit is connected to a corresponding radio frequency interface; multiple basic regular antenna subarrays are fully distributed in the middle position of the phased array antenna surface, and multiple irregular antenna subarrays are sparsely distributed at the edge positions of the phased array antenna surface.

[0059] In this embodiment, the following specific implementation examples are used only to illustrate the arrangement principle of the phased array antenna, but not to limit the phased array antenna. Figure 7 An example diagram of a phased array antenna provided in an embodiment of the present invention is shown. Figure 8 For the simulated radiation pattern of a phased array antenna provided in the embodiment of the present invention, please refer to Figure 7 and Figure 8 According to the antenna integration principle, an amplitude-weighted distribution with low sidelobes has the characteristics of reduced center attenuation and large edge attenuation. Based on this, the following phased array antenna layout concept is designed: multiple basic regular antenna subarrays are fully arrayed in the center of the phased array antenna array, and multiple irregular antenna subarrays are sparsely arrayed at the edges of the phased array antenna array. Specifically, the subarray arrangement positions of the multiple irregular antenna subarrays and the positions of the antenna units connected to the RF interface in the irregular antenna subarrays are obtained through algorithm optimization. The optimization algorithm can be a genetic algorithm, a particle swarm algorithm, or other optimization algorithm, which is not limited in this application.

[0060] like Figure 7 As shown, only Figure 7 The phased array antenna shown in the figure is an example and does not limit the composition of the phased array antenna. Figure 7 The center of the phased array antenna array shown is used as the origin to establish a plane rectangular coordinate system. The phased array antenna will be divided into four quadrants, and the arrangement positions of the sub-arrays in the four quadrants are mirror-symmetrically distributed, that is, the part of the phased array antenna contained in the first quadrant and the part of the phased array antenna contained in the second quadrant are mirror-symmetrical about the Y axis, the part of the phased array antenna contained in the first quadrant and the part of the phased array antenna contained in the fourth quadrant are mirror-symmetrical about the X axis, and the part of the phased array antenna contained in the first quadrant and the part of the phased array antenna contained in the third quadrant are symmetrical about the origin. There is no overlap between the sub-arrays in the phased array antenna. In order to reduce the complexity of the phased array antenna array layout process, it is often only necessary to optimize the sub-array position and sub-array type in one of the four quadrants (for example, the first quadrant). In this way, the computational complexity of the algorithm is also effectively reduced. However, when actually designing a phased array antenna, in order to effectively improve the sidelobe suppression capability of the phased array antenna, the phased array antenna array can also be directly arranged by optimizing the position and type of each sub-array in the entire phased array antenna array. In this case, if a plane rectangular coordinate system is established with the center of the array surface of the designed phased array antenna as the origin, some phased array antennas divided into the four quadrants may not be distributed in a mirror-symmetrical manner.

[0061] In this embodiment, the phased array antenna is sparsely distributed using subarrays as units, which reduces the number of subarrays to reduce the hardware cost of the phased array antenna while effectively improving the sidelobe suppression level, so that the optimized phased array antenna has better sidelobe suppression capability.

[0062] Optionally, as a specific implementation of the phased array antenna provided in an embodiment of the present invention, the spacing between any two adjacent antenna units in the irregular antenna subarray is the same as the spacing between any two adjacent antenna units in the basic regular antenna subarray.

[0063] In this embodiment, please refer to Figure 7 , only Figure 7 The phased array antenna is used as an example, but is not limited to this. Figure 7 The phased array antenna in this example is composed of multiple 9-choose-4 irregular antenna subarrays and multiple basic regular antenna subarrays. The distance between any two adjacent antenna elements in the 9-choose-4 irregular antenna subarray is equal to the distance between any two antenna elements in the basic regular antenna subarray. Typically, the distance between any two adjacent antenna elements in the irregular antenna subarray and the distance between any two antenna elements in the basic regular antenna subarray are 0.5λ-0.7λ, where λ is the wavelength corresponding to the operating frequency of the phased array antenna.

[0064] by Figure 7 Take the application of the phased array antenna in the phased array radar as an example. In the phased array radar, one end of the T / R component is connected to the antenna and the other end is connected to the intermediate frequency processing unit to form a wireless transceiver system. The function of this wireless transceiver system is to amplify, phase shift and attenuate the signal. Figure 7 The phased array antenna shown is composed of a basic regular antenna subarray and a 9-choose-4 irregular antenna subarray. The basic regular antenna subarray is a 2×2 subarray formed by 4 antenna elements arranged in a matrix, and the 9-choose-4 irregular antenna subarray is a 3×3 subarray formed by 9 antenna elements arranged in a matrix. The 9-choose-4 irregular antenna subarray and the basic regular antenna subarray can use the same T / R components, and the RF interfaces on the T / R components are connected to the corresponding antenna elements at equal distances. Furthermore, when designing a phased array antenna, the spacing between any two adjacent antenna elements in the irregular antenna subarray can also be different from the spacing between any two adjacent antenna elements in the basic regular antenna subarray. In the actual design process of phased array antennas, the selection of the distance between any two adjacent antenna elements in each subarray is related to factors such as the size of the antenna elements and the lobe width of the array radiation pattern. Therefore, under the requirement of effectively improving the sidelobe suppression capability of the phased array antenna, for each type of subarray in the phased array antenna array, the distance between any two adjacent antenna elements in the irregular antenna subarray and the distance between any two adjacent antenna elements in the basic regular antenna subarray can be different. As long as the distance between the RF interface of the same type of subarray and the four adjacent antenna elements arranged in a matrix form in its corresponding antenna combination is equal, the equal phase requirement is met.

[0065] Optionally, as a specific implementation of the phased array antenna provided in an embodiment of the present invention, the irregular antenna subarray and the basic regular antenna subarray have the same number of radio frequency interfaces.

[0066] In this embodiment, Figure 7 In the illustrated phased array antenna, the 9-choose-4 irregular antenna subarray has the same number of RF interfaces as the basic regular antenna subarray. Furthermore, in actual design of a phased array antenna, the number of RF interfaces in the irregular antenna subarray and the basic regular antenna subarray can also be different. Figure 9 For an example diagram of a class of irregular antenna subarrays provided by an embodiment of the present invention, please refer to Figure 9 , Figure 9 4 types of 6-choose-4 irregular antenna subarrays are shown, and the number of RF interfaces of the irregular antenna subarray is 2. Figure 9Taking the construction of a phased array antenna using 6-select-4 irregular antenna subarrays and basic regular antenna subarrays as an example, multiple basic regular antenna subarrays are fully arrayed in the middle position of the phased array antenna array, and multiple 6-select-4 irregular antenna subarrays are sparsely arrayed at the edge positions of the phased array antenna array. Specifically, the subarray arrangement positions of the multiple 6-select-4 irregular antenna subarrays and the positions of the antenna units connected to the RF interface in the 6-select-4 irregular antenna subarrays are obtained through algorithm optimization. The optimization algorithm can be a genetic algorithm, a particle swarm algorithm, or other optimization algorithms, which is not limited in this application. In this phased array antenna, the number of RF interfaces in the two types of subarrays used is not the same.

[0067] Optionally, as a specific implementation of the phased array antenna provided in an embodiment of the present invention, the irregular antenna subarrays are divided into different types according to different antenna units connected to each radio frequency interface in the irregular antenna subarray.

[0068] The number of irregular antenna subarrays in the phased array antenna does not exceed a preset value.

[0069] In this embodiment, Figure 6 Taking the 9-choose-4 irregular antenna subarray shown as an example, the antenna units connected to each RF interface in the 9-choose-4 irregular antenna subarray are different, and the irregular antenna subarrays formed are also different. In order to ensure that each RF interface in each irregular antenna subarray of the phased array antenna is connected to its corresponding four adjacent antenna units arranged in a matrix form to meet the equal phase condition, a constraint is set that the positions of the antenna units to be connected to the four RF interfaces in the 9-choose-4 irregular antenna subarray are not allowed to have the three antenna units in the outermost row or outermost column selected and connected at the same time. On this basis, the types of 9-choose-4 irregular antenna subarrays available are C9 4 -4=122 types. Furthermore, in order to reduce process complexity and manufacturing cost, the types of 9-choose-4 irregular antenna subarrays usually selected do not exceed 5. Figure 9 This is a schematic diagram illustrating a class of irregular antenna subarrays provided by an embodiment of the present invention. Figure 10 Please refer to the schematic diagram of the principle of a class of irregular antenna subarrays provided in the embodiment of the present invention. Figure 9 and Figure 10 , Figure 9 There are several examples of 6-choose-2 irregular antenna subarrays. Figure 10 The figure shows multiple examples of 16-choose-4 irregular antenna subarrays. In the process of designing phased array antennas, in order to reduce process complexity, the appropriate type and number of irregular antenna subarrays can be selected according to actual conditions.

[0070] In this embodiment, in order to further improve the sidelobe suppression capability of the phased array antenna, the irregular antenna subarrays are divided into different types according to the different antenna units connected to each RF interface in the irregular antenna subarray. In each type of irregular antenna subarray, the phased array antenna can be sparsely distributed based on each antenna unit, which effectively increases the degree of freedom of antenna optimization and the sidelobe suppression capability of the phased array antenna.

[0071] Optionally, as a specific implementation of the phased array antenna provided in an embodiment of the present invention, the basic regular antenna subarray is a 2×2 subarray formed by 4 antenna units arranged in a matrix form, and the irregular antenna subarray is a 3×3 subarray formed by 9 antenna units arranged in a matrix form.

[0072] Please refer to Figure 7 In this embodiment, the basic regular antenna subarray is a 2×2 subarray formed by 4 antenna units arranged in a matrix form, and the 9-choose-4 irregular antenna subarray is a 3×3 subarray formed by 9 antenna units arranged in a matrix form.

[0073] Optional, please refer to Figure 7 As a specific implementation of the phased array antenna provided in an embodiment of the present invention, in this embodiment, the number of 9-choose-4 irregular antenna subarrays in the phased array antenna is 48, and the number of basic regular antenna subarrays is 72. The phased array antenna is a low-sidelobe sparse array with a scale of 480 elements.

[0074] An embodiment of the present invention provides a method for designing a phased array antenna, which is used to generate the above phased array antenna or the phased array antenna described in any one of the above possible implementations.

[0075] The method includes:

[0076] The positions of the basic regular antenna subarrays, the irregular antenna subarrays, and the positions of the antenna units connected to the RF interface in each irregular antenna subarray are used as optimization variables. The optimal values of each optimization variable are found through an optimization algorithm to obtain a phased array antenna.

[0077] In this embodiment, Figure 11 Please refer to the implementation flow chart of the design method of the phased array antenna provided in the embodiment of the present invention. Figure 7 and Figure 11 In this embodiment, a subarray-level hybrid layout genetic algorithm under multiple constraints is provided to design a phased array antenna to construct Figure 7 Take the phased array antenna shown as an example, Figure 7The subarray types of phased array antennas include basic regular antenna subarrays and irregular antenna subarrays. Considering the symmetry of the array radiation pattern in space, when designing the phased array antenna, a plane rectangular coordinate system is constructed with the center of the phased array antenna as the origin. The phased array antenna is evenly divided into four quadrants, and the entire array surface presents a four-quadrant mirror-symmetrical distribution structure. Considering the problem of reducing the complexity of the phased array antenna array layout process, only the subarray position and subarray type in one of the four quadrants (for example, the first quadrant) need to be optimized. In this way, the computational complexity is also effectively reduced. Figure 7 As shown, the center of the phased array antenna is fully populated with 2×2 subarrays, while the edge of the phased array antenna is sparsely populated with 9-choose-4 irregular antenna subarrays. The positions of the 2×2 subarrays in the phased array antenna, the sparse positions of the 9-choose-4 irregular antenna subarrays, and the selected positions of the antenna units connected to the RF interface in each 9-choose-4 irregular antenna subarray are used as optimization variables. A genetic algorithm is used to find the optimal value of each optimization variable to obtain the phased array antenna. Furthermore, the optimization algorithm can also be a particle swarm optimization algorithm or other optimization algorithm, which is not limited in this application.

[0078] In this embodiment, through genetic operations such as selection, crossover, and mutation under multiple constraints, the positions of the 2×2 subarrays in the phased array antenna, the sparse positions of the 9-choose-4 irregular antenna subarrays, and the selected positions of the antenna units connected to the RF interface in each 9-choose-4 irregular antenna subarray are optimized to obtain the optimized optimal phased array antenna. Figure 8 Through simulation, the normalized radiation pattern of the optimal phased array antenna was obtained. It can be seen from the figure that the sidelobe level of the optimal phased array antenna reached -24.5dB, which effectively improved the sidelobe suppression capability of the phased array antenna.

[0079] Optionally, as a specific implementation of the phased array antenna design method provided in an embodiment of the present invention, the optimization algorithm is a genetic algorithm, and finding the optimal value of each of the optimization variables through the genetic algorithm includes:

[0080] The parameters of the genetic algorithm are set and an initial population is generated. Each individual in the initial population is a set of optimization variables. Each set of optimization variables includes the position of a basic regular antenna subarray, the position of an irregular antenna subarray, and the position of antenna units connected to a radio frequency interface in each irregular antenna subarray.

[0081] Calculate the fitness value corresponding to each individual and determine the individual corresponding to the maximum fitness value.

[0082] Individuals in the initial population are selected, crossed over, and mutated to generate a new population.

[0083] Calculate the fitness value corresponding to each individual in the new population, and update the individual corresponding to the maximum fitness value, and iterate continuously until the maximum number of iterations is reached.

[0084] The optimal value of each optimization variable is determined according to the individual corresponding to the maximum fitness value.

[0085] Optionally, as a specific implementation of the phased array antenna design method provided in an embodiment of the present invention, the formula for calculating the fitness value corresponding to each individual in the new population is:

[0086] y=abs(MSLL)

[0087]

[0088]

[0089]

[0090]

[0091] Wherein, y is the formula for calculating the fitness value corresponding to each individual in the new population, abs represents the absolute value function, MSLL is the maximum sidelobe level of the elevation projection pattern, S represents θ=θ0, The sidelobe interval of the elevation projection pattern, ψ0 represents half the main lobe width, F theta (θ) is the elevation projection pattern function of the phased array antenna surface, is the radiation pattern function of the phased array antenna, N1 and N2 represent the number of basic regular antenna subarrays and the number of irregular antenna subarrays in the phased array antenna, respectively. xi d yi They represent the horizontal and vertical coordinates of each antenna unit when the plane rectangular coordinate system is established with the center of the phased array antenna as the origin. represents the unit field, j is the unit of the imaginary part of the complex number, k is the wave number corresponding to the operating frequency of the phased array antenna, Indicates the beam pointing angle.

[0092] In this embodiment, Figure 7 Taking the phased array antenna shown in the figure as an example, a plane rectangular coordinate system XOY is established with the center of the phased array antenna plane as the origin. The radiation pattern function of the phased array antenna array is: in, is the radiation pattern function of the phased array antenna, N1 and N2 represent the number of basic regular antenna subarrays and the number of irregular antenna subarrays in the phased array antenna, respectively. xi d yiThey represent the horizontal and vertical coordinates of each antenna unit when the plane rectangular coordinate system is established with the center of the phased array antenna as the origin. represents the unit field, j is the unit of the imaginary part of the complex number, k is the wave number corresponding to the operating frequency of the phased array antenna, Represents the beam pointing angle. According to the definition of Maximum Sidelobe Level (MSLL), in order to ensure that the radiation pattern is omnidirectional and has low side lobes in the radiation space, the fitness function is taken as the maximum sidelobe level MSLL of the elevation projection radiation pattern: Among them, F theta (θ) is the elevation projection pattern function of the phased array antenna, max represents the maximum value function, S represents θ=θ0, When the side lobe interval of the elevation projection pattern is , the main lobe zero power point of the elevation projection pattern is 2ψ0, then The optimization goal is set to: max(abs(MSLL)), where abs represents the absolute value function. After genetic operations such as selection, crossover, and mutation under multiple constraints, the optimal sparse array layout is obtained as follows Figure 7 As shown, the middle part of the phased array antenna array adopts a full array of 2×2 sub-arrays, and the edge position adopts five sparse arrays of 3×3 sub-arrays. The simulated radiation pattern of the phased array antenna is shown in Figure 8 As shown in the figure, its sidelobe level reaches -24.5dB, which greatly reduces the sidelobe of the phased array antenna array.

[0093] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.

Claims

1. An irregular antenna subarray, characterized in that: include: multiple antenna units; The multiple antenna units are arranged in a matrix form, each row and each column of the matrix includes at least two antenna units, and the distance between any two adjacent antenna units is equal; At least one RF interface is also provided on the matrix plane, each RF interface corresponds to an antenna combination, the antenna combination is composed of any four adjacent antenna units arranged in a matrix form, the RF interface is located at the center point of the four adjacent antenna units arranged in a matrix form in the corresponding antenna combination, the RF interface is equidistant from the four adjacent antenna units arranged in a matrix form and is connected to any one of the four adjacent antenna units arranged in a matrix form; and, for any antenna unit, the antenna unit is connected to at most one RF interface, and the antenna unit belongs to at least one target antenna combination, and the target antenna combination is an antenna combination having a corresponding RF interface.

2. A phased array antenna, characterized in that: The phased array antenna is composed of a plurality of basic regular antenna sub-arrays and a plurality of irregular antenna sub-arrays as claimed in claim 1; Among them, the basic regular antenna subarray includes multiple antenna units arranged in a matrix form, and each antenna unit is correspondingly connected to a radio frequency interface; the multiple basic regular antenna subarrays are fully distributed in the middle position of the phased array antenna surface, and the multiple irregular antenna subarrays are sparsely distributed at the edge positions of the phased array antenna surface.

3. The phased array antenna according to claim 2, wherein: The spacing between any two adjacent antenna units in the irregular antenna subarray is the same as the spacing between any two adjacent antenna units in the basic regular antenna subarray.

4. The phased array antenna according to claim 2, wherein: The irregular antenna subarray and the basic regular antenna subarray have the same number of radio frequency interfaces.

5. The phased array antenna according to claim 2, wherein: Classifying the irregular antenna subarray into different types according to different antenna units connected to each radio frequency interface in the irregular antenna subarray; The number of types of the irregular antenna sub-arrays in the phased array antenna does not exceed a preset value.

6. The phased array antenna according to claim 2, wherein: The basic regular antenna subarray is a 2×2 subarray formed by 4 antenna units arranged in a matrix form, and the irregular antenna subarray is a 3×3 subarray formed by 9 antenna units arranged in a matrix form.

7. The phased array antenna according to claim 6, wherein: The number of the irregular antenna subarrays is 48, and the number of the basic regular antenna subarrays is 72.

8. A method for designing a phased array antenna, characterized in that: The method is used to generate the phased array antenna according to any one of claims 2 to 7; The method comprises: The positions of the basic regular antenna subarrays, the irregular antenna subarrays, and the positions of the antenna units connected to the radio frequency interface in each irregular antenna subarray are used as optimization variables. The optimal values of each of the optimization variables are found through an optimization algorithm to obtain the phased array antenna.

9. The method for designing a phased array antenna according to claim 8, wherein: The optimization algorithm is a genetic algorithm, and the optimal value of each optimization variable is found by the genetic algorithm, including: Setting parameters for a genetic algorithm and generating an initial population; wherein each individual in the initial population is a set of optimization variables, and each set of optimization variables includes a position of a basic regular antenna subarray, a position of an irregular antenna subarray, and a position of an antenna unit connected to a radio frequency interface in each irregular antenna subarray; Calculate the fitness value corresponding to each individual and determine the individual corresponding to the maximum fitness value; Selecting, crossing over, and mutating individuals in the initial population to generate a new population; Calculate the fitness value corresponding to each individual in the new population, and update the individual corresponding to the maximum fitness value, and iterate continuously until the maximum number of iterations is reached; The optimal value of each optimization variable is determined according to the individual corresponding to the maximum fitness value.

10. The method for designing a phased array antenna according to claim 9, wherein: The formula for calculating the fitness value corresponding to each individual in the new population is: y=abs(MSLL) Wherein, y is the formula for calculating the fitness value corresponding to each individual in the new population, abs represents the absolute value function, MSLL is the maximum sidelobe level of the elevation projection pattern, S represents θ=θ0, The sidelobe interval of the elevation projection pattern, ψ0 represents half the main lobe width, F theta (θ) is the elevation projection pattern function of the phased array antenna surface, is the radiation pattern function of the phased array antenna, N1 and N2 represent the number of basic regular antenna subarrays and irregular antenna subarrays in the phased array antenna, respectively. They represent the horizontal and vertical coordinates of each antenna unit when the plane rectangular coordinate system is established with the center of the phased array antenna as the origin. represents the unit field, j is the unit of the imaginary part of the complex number, k is the wave number corresponding to the operating frequency of the phased array antenna, Indicates the beam pointing angle.

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