Lightweight design method of phased array antenna

Abstract

This invention discloses a lightweight design method for phased array antennas. The phased array antenna adopts a lightweight design approach, using a composite structure of a carbon fiber mounting frame and an aluminum honeycomb sandwich support plate for the load-bearing structure. This reduces the overall weight of the device while meeting load-bearing requirements. By rationally utilizing the structural shapes of the components, the discrete structural design is transformed into an integrated functional structure design. The component structure is designed as a long strip shape, and the front and back components of the load-bearing structure are arranged in a cross shape. This method improves the overall stiffness of the phased array antenna without increasing weight. The fundamental frequency of the phased array antenna is greater than 100Hz, effectively avoiding coupled vibration between the phased array antenna and the platform. The structural stiffness meets the requirements for mechanical environmental resistance design.

Description

Technical Field

[0001] This invention belongs to the field of phased array antenna support structure, and specifically relates to a lightweight design method for phased array antennas. Background Technology

[0002] The structure supporting phased array antennas is developing towards larger aperture, higher heat dissipation, higher integration, and higher performance, which leads to a continuous increase in the structural size, array size, and weight of phased array antennas. As the structural size and weight increase, the overall structural stiffness of the phased array antenna will further decrease. If the first-order natural vibration frequency of the phased array antenna can be guaranteed to be ≥100Hz, the coupling vibration between the phased array antenna and the platform can be effectively avoided, reducing the risk of failure of internal components of the phased array antenna due to vibration.

[0003] Patent application 202310903910.X discloses a frameless phased array antenna support structure, which improves the structural rigidity of the passive antenna through gridded reinforcing ribs; patent application 202310969759.X discloses a spaceborne integrated SAR satellite platform, which solves the problems of high-precision unit installation requirements and low structural strength by padding a 2-3mm metal shim on the honeycomb board. The above-mentioned existing inventions, by increasing rigidity through additional reinforcing ribs and metal shims, result in increased weight and limit the utilization of effective space. Summary of the Invention

[0004] The purpose of this invention is to provide a lightweight design method for phased array antennas. By combining the lightweight load-bearing structure with the functional structure in an integrated design, the overall rigidity is improved while achieving weight reduction.

[0005] The technical solution for achieving the present invention is: a lightweight design method for a phased array antenna, comprising the following steps:

[0006] Step 1: Due to the limitations of platform space size, weight, and usage environment requirements, the phased array antenna size must not exceed 800 mm × 700 mm × 200 mm, and the weight must not exceed 50 kg. The phased array antenna must also have the characteristics of low profile, lightweight, and efficient heat dissipation.

[0007] Step 2: Considering the function of the phased array antenna, design the structure of the phased array antenna:

[0008] A phased array antenna includes an active subarray, a supporting structure, a first component, a second component, and a third component;

[0009] Step 3: Considering the lightweight requirements of the load-bearing structure, design the load-bearing structure for the phased array antenna:

[0010] The load-bearing structure includes a support plate and a mounting frame;

[0011] Step 4: Considering the lightweight requirements, design the installation frame;

[0012] Step 5: Considering lightweight requirements, design the support plate;

[0013] Step 6: Consider the stiffness requirements of the phased array antenna and design the structural layout of the phased array antenna.

[0014] Compared with the prior art, the significant advantages of this invention are:

[0015] (1) The phased array antenna bearing structure adopts a lightweight design concept. The bearing structure adopts a composite structure of carbon fiber mounting frame and aluminum honeycomb sandwich panel support plate, which reduces the weight of the whole machine while meeting the bearing requirements.

[0016] (2) Make reasonable use of the structural shape of the components to transform the discrete structural design into an integrated functional structural design. The component structure is designed as a long strip shape. The front and back components of the load-bearing structure are arranged in a cross shape. This method improves the overall stiffness of the phased array antenna without increasing the weight. The fundamental frequency of the phased array antenna is greater than 100Hz, which effectively avoids the coupling vibration between the phased array antenna and the platform. The structural stiffness meets the requirements of the anti-mechanical environment design. Attached Figure Description

[0017] Figure 1 This is a diagram of the structure supporting a phased array antenna.

[0018] Figure 2 This is a diagram of the load-bearing structure.

[0019] Figure 3 This is a diagram showing the components of the installation frame.

[0020] Figure 4 This is a diagram of the support plate assembly.

[0021] Figure 5 This is a layout diagram of the integrated functional structure.

[0022] Figure 6 This is the first-order mode shape diagram of the phased array antenna. Detailed Implementation

[0023] Combination Figure 1 , Figure 2 , Figure 3 , Figure 4 A lightweight design method for phased array antennas, comprising the following steps:

[0024] Step 1: Due to limitations in platform space size, weight, and usage environment, the phased array antenna must be no larger than 800 mm × 700 mm × 200 mm and no larger than 50 kg. The phased array antenna must also have the characteristics of low profile, lightweight, and efficient heat dissipation.

[0025] Step 2: Consider the function of the phased array antenna and design its structure.

[0026] The phased array antenna includes an active subarray 1, a support structure 2, a first component 3, a second component 4, and a third component 5. The phased array antenna uses the support structure 2 as the mounting interface. The active subarray 1 is arranged on the front of the support structure 2, and the first component 3, the second component 4, and the third component 5 are arranged on the back of the support structure 2. Each component is integrated using a combination of blind plugging and cable interconnection according to the structural layout.

[0027] The first component, 3, is used for wave control.

[0028] The second component, 4, is used for power supply.

[0029] The third component, Component 5, is used for the distribution of wave control and power supply.

[0030] Step 3: Considering the lightweight requirements of the support structure 2, design the support structure 2 of the phased array antenna.

[0031] The load-bearing structure 2 includes a support plate 6 and a mounting frame 7. Considering lightweight requirements, the mounting frame 7 is made of carbon fiber laminate, with a density of 1.8 g / cm³. 3 Compared to traditional metal materials (aluminum alloy has a density of 2.7 g / cm³), 3 The density of titanium alloy is 4.45 g / cm³. 3Carbon fiber composites have a relatively light weight, with a specific strength of approximately 2.72 GPa and a specific modulus of approximately 127.8 GPa. Compared to traditional metal materials (aluminum alloys have a specific strength of approximately 0.14 GPa and a specific modulus of approximately 24.5 GPa, and titanium alloys have a specific strength of approximately 0.895 GPa and a specific modulus of approximately 22.5 GPa), they have higher specific strength and specific modulus. Moreover, the phased array antenna support structure 2 is installed on the outer surface of the spacecraft. The space environment, such as deep cryogenic space and solar radiation, has a huge impact on its temperature. The material of the support structure is required to have high dimensional stability and a small coefficient of linear expansion. Carbon fiber composites can achieve a coefficient of expansion close to zero through reasonable layup design. The support plate 6 is made of aluminum honeycomb sandwich panel, a typical lightweight structural component consisting of upper and lower panels and a honeycomb core. The panels and the honeycomb core are bonded together with adhesive. The panels are thin sheet materials with high strength and stiffness, while the core is a lightweight honeycomb material. Due to the continuous support of the honeycomb core on the upper and lower panels, the thin panels can fully exert their in-plane tensile or compressive load-bearing capacity without buckling, exhibiting high specific strength and specific stiffness performance. After 3D modeling and calculation, the structural scheme of the load-bearing structure 2, which uses a composite structure of carbon fiber mounting frame 7 and support plate 6 (aluminum honeycomb sandwich panel), can reduce the weight by at least 50% compared to the structural scheme using a single thick metal sheet. The support plate 6 and mounting frame 7 are connected and fixed by several screws, forming the main load-bearing structure of the phased array antenna after assembly. This provides mounting surfaces, mounting space, and mounting positioning for the active subarray 1, the first component 3, the second component 4, and the third component 5, while ensuring the required rigidity for component installation.

[0032] Step 4: Considering the lightweight requirements, design the installation frame 7.

[0033] The mounting frame 7 is made of high-strength carbon fiber material and consists of a support frame 8 and several reinforcing members 9. The support frame 8 adopts a "C"-shaped cross-section structure, and is reinforced by the reinforcing members 9. The reinforcing members 9 and the support frame 8 are bonded and fixed together using room-temperature curing structural adhesive. The coefficient of thermal expansion of carbon fiber along its fiber direction is negative. The inner layer of the carbon fiber frame uses a quasi-isotropic layup design (0°, 45°, -45°, 90°) to achieve a coefficient of thermal expansion approaching zero. At least 10% of the material is laid up at angles of 0°, 45°, -45°, and 90° in each of the four main directions. The outer surface of the carbon fiber frame uses a (45°, -45°) layup design to improve the material's impact resistance.

[0034] Step 5: Considering the lightweight requirements, design the support plate 6.

[0035] The support plate 6 adopts a honeycomb sandwich panel structure, consisting of an upper panel 10, a lower panel 11, and a honeycomb core 12 in the middle. The upper panel 10, lower panel 11, and honeycomb core 12 are bonded together with adhesive. To meet the strength and stiffness requirements of the honeycomb sandwich panel, the thickness of the upper panel 10 and lower panel 11 is sufficient to withstand the in-plane tensile, compressive, and shear stresses caused by the design load, and the honeycomb core 12 has sufficient height, transverse shear strength, and stiffness. The upper panel 10 and lower panel 11 are made of 0.3mm thick 2A12 T4 aluminum alloy, and the honeycomb core 12 is made of 4×0.04 square regular hexagonal 5A02 aluminum honeycomb with a thickness of 19.4mm. The thickness of the entire support plate 6 is 20mm. The sidewalls of the honeycomb core 12 are perforated to allow residual air to escape when working in a vacuum environment. The adhesive used between the upper panel 10, the lower panel 11, and the middle honeycomb core 12 is J-78B epoxy resin adhesive, which is cured at 120℃. To achieve the installation and positioning of the internal components of the phased array antenna, embedded parts 13 are inserted during the manufacturing process of the honeycomb sandwich panel. Before the honeycomb sandwich panel cures, the embedded parts 13 and the honeycomb core 12 are bonded together with J-78D foam adhesive, and then bonded to the upper panel 10 and the lower panel 11 for co-curing. To ensure the accuracy of the mounting hole positions for the active subarray 1, the first component 3, the second component 4, and the third component 5, holes are machined as a whole after the honeycomb sandwich panel has cured and formed. Several parallel heat pipes 14 are also provided between the embedded parts 13 in the honeycomb sandwich panel. The height of the heat pipes 14 is consistent with the height of the honeycomb core 12, so that the heat pipes 14 and the upper panel 10 and the lower panel 11 are in good contact. The heat pipes 14 achieve the heat dissipation and temperature uniformity requirements of the active subarray 1, the first component 3, the second component 4 and the third component 5.

[0036] Step 6: Consider the stiffness requirements of the phased array antenna and design the structural layout of the phased array antenna.

[0037] Assuming that the active subarray 1, the first component 3, the second component 4, and the third component 5 are discrete structural components, and their structural shapes do not provide additional stiffness to the support plate 6, the weight of the active subarray 1, the first component 3, the second component 4, and the third component 5 is simulated using mass points. The simulation shows that the fundamental frequency of the phased array antenna is 45-55Hz, which is much less than 100Hz. There is a risk of coupled vibration between the phased array antenna and the platform.

[0038] Combination Figure 5By making reasonable use of the structural shapes of the active subarray 1, the first component 3, the second component 4, and the third component 5, the discrete structural design is transformed into an integrated functional structural design. The active subarray 1, the first component 3, the second component 4, and the third component 5 are designed in a long strip shape. The active subarray 1 is arranged in a cross shape with the first component 3, the second component 4, and the third component 5 respectively. Through the above arrangement, without increasing the weight, the structural shapes of the active subarray 1, the first component 3, the second component 4, and the third component 5 provide additional stiffness to the support plate 6, thereby improving the overall stiffness of the phased array antenna.

[0039] Combination Figure 6 After layout optimization and adjustment, the component modeling was incorporated into the simulation model. The simulation showed that the fundamental frequency of the phased array antenna was 123.3Hz, which is greater than 100Hz. This effectively avoids coupling vibration between the phased array antenna and the platform, and the structural stiffness meets the design requirements for anti-mechanical environment.

Claims

1. A lightweight design method for a phased array antenna, characterized in that, The steps are as follows: Step 1: Due to the limitations of platform space size, weight, and usage environment requirements, the phased array antenna size must not exceed 800 mm × 700 mm × 200 mm, and the weight must not exceed 50 kg. The phased array antenna must also have the characteristics of low profile, lightweight, and efficient heat dissipation. Step 2: Considering the function of the phased array antenna, design the structure of the phased array antenna: The phased array antenna includes an active subarray (1), a support structure (2), a first component (3), a second component (4), and a third component (5); Step 3: Considering the lightweight requirements of the supporting structure (2), design the supporting structure (2) of the phased array antenna: The load-bearing structure (2) includes a support plate (6) and a mounting frame (7); Step 4: Considering the lightweight requirements, design the installation frame (7). Step 5: Considering the lightweight requirements, design the support plate (6). Step 6: Consider the stiffness requirements of the phased array antenna and design the structural layout of the phased array antenna.

2. The lightweight design method for a phased array antenna according to claim 1, characterized in that: In step 2, the phased array antenna uses the carrier structure (2) as the installation interface. The front of the carrier structure (2) is arranged with the source subarray (1), and the back of the carrier structure (2) is arranged with the first component (3), the second component (4), and the third component (5). Each component is integrated according to the structural layout using a combination of blind plugging and cable interconnection.

3. The lightweight design method for a phased array antenna according to claim 2, characterized in that: The first component (3) is used for wave control, the second component (4) is used for power supply, and the third component (5) is used for the allocation of wave control and power supply.

4. The lightweight design method for a phased array antenna according to claim 2, characterized in that: In step 3, the support plate (6) and the mounting frame (7) are connected and fixed by several screws. After assembly, they form the main load-bearing structure of the phased array antenna, providing the mounting surface, mounting space and mounting positioning for the active subarray (1), the first component (3), the second component (4) and the third component (5), and ensuring the rigidity required for component installation.

5. The lightweight design method for a phased array antenna according to claim 4, characterized in that: In step 4, the mounting frame (7) is made of high-strength carbon fiber material. The mounting frame (7) consists of a support frame (8) and several reinforcing members (9). The support frame (8) adopts a "C" shaped cross-section structure. The reinforcing members (9) are used to strengthen the support frame (8). The reinforcing members (9) and the support frame (8) are bonded and fixed with room temperature curing structural adhesive. The thermal expansion coefficient of carbon fiber along the fiber direction is negative. The inner layer of the mounting frame adopts a quasi-isotropic ply design of 0°, 45°, -45°, and 90° to make the expansion coefficient of the material approach zero. The ply at angles of 0°, 45°, -45°, and 90° in the four main directions accounts for at least 10% of the total. The outer surface of the mounting frame adopts a 45° and -45° ply design to improve the impact resistance of the material.

6. The lightweight design method for a phased array antenna according to claim 5, characterized in that: In step 5, the support plate (6) adopts a honeycomb sandwich panel structure. The support plate (6) consists of an upper panel (10), a lower panel (11) and a middle honeycomb core (12). The upper panel (10), the lower panel (11) and the middle honeycomb core (12) are bonded together with adhesive. In order to meet the strength and stiffness requirements of the honeycomb sandwich panel, the thickness of the upper panel (10) and the lower panel (11) is sufficient to withstand the in-plane tensile, compressive and shear stress caused by the design load. The honeycomb core (12) has sufficient height, transverse shear strength and stiffness.

7. The lightweight design method for a phased array antenna according to claim 6, characterized in that: In order to achieve the installation and positioning of the internal components of the phased array antenna, embedded parts (13) are embedded in the honeycomb sandwich panel during the manufacturing process. Before the honeycomb sandwich panel is cured, the embedded parts (13) and the honeycomb core (12) are bonded together with J-78D foam adhesive, and then bonded together with the upper panel (10) and the lower panel (11) and co-cured. In order to ensure the accuracy of the mounting hole positions of the active subarray (1), the first component (3), the second component (4), and the third component (5), the honeycomb sandwich panel is machined after curing. Several parallel heat pipes (14) are also provided between the embedded parts (13) in the honeycomb sandwich panel. The height of the heat pipes (14) is consistent with the height of the honeycomb core (12), so that the heat pipes (14) and the upper panel (10) and the lower panel (11) are in good contact. The heat pipes (14) achieve the heat dissipation and temperature uniformity requirements of the active subarray (1), the first component (3), the second component (4), and the third component (5).

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