Radar antenna cover of a multilayer composite structure

Abstract

The utility model relates to antenna cover technical field especially is a radar antenna cover of multilayer composite structure, including antenna cover body, the antenna cover body includes hydrophobic antifouling layer, first skin layer, gradient formula honeycomb core layer, impedance matching overlayer, second skin layer from outside to inside in proper order, and hydrophobic antifouling layer, first skin layer, gradient formula honeycomb core layer, impedance matching overlayer, second skin layer each layer is closely attached along the thickness direction, and is integrated through the hot-pressing solidification nodule, and the edge adopts laser seal welding, and the hydrophobic antifouling layer, first skin layer, gradient formula honeycomb core layer, impedance matching overlayer, second skin layer are set from outside to inside in proper order to the antenna cover body, and through impedance matching overlayer design and low-loss skin material selection, the reflection loss problem caused by the existing structure impedance abrupt change has been solved, and the gradient formula honeycomb core layer is combined Kevlar fibre suture line, makes the antenna cover impact strength promotion.

Description

Technical Field

[0001] This utility model relates to the field of radome technology, and in particular to a radar radome with a multi-layer composite structure. Background Technology

[0002] As a key component protecting the antenna system from environmental corrosion, the radar radome must simultaneously meet two core requirements: electromagnetic wave transmission and mechanical protection.

[0003] In existing technologies, radar radomes mostly adopt a three-layer honeycomb sandwich structure (upper and lower skins + single-aperture honeycomb core). However, this structure has obvious defects: in order to ensure wave transmission, the skin thickness needs to be reduced, resulting in insufficient mechanical strength, especially for ultra-large radomes that are prone to deformation; the single-aperture honeycomb core is difficult to balance the requirements of rigidity and lightweight, and cracks are prone to propagate over a large area after impact.

[0004] Therefore, we urgently need a radar radome with a multi-layered composite structure. Utility Model Content

[0005] This utility model addresses the shortcomings of existing technologies by providing the following technical solution: a multi-layer composite radar radome, comprising a radome body, wherein the radome body comprises, from the outside to the inside, a hydrophobic and antifouling layer, a first skin layer, a gradient honeycomb core layer, an impedance matching transition layer, and a second skin layer, wherein each of the hydrophobic and antifouling layer, the first skin layer, the gradient honeycomb core layer, the impedance matching transition layer, and the second skin layer is tightly bonded together along the thickness direction and is solidified into a single unit by hot pressing, and the edges are sealed by laser welding; The gradient honeycomb core layer is a closed-cell honeycomb structure. The honeycomb pore size of the gradient honeycomb core layer increases in a stepwise manner from the side near the first skin layer to the side near the impedance matching transition layer. Each of the first skin layer, the gradient honeycomb core layer, and the impedance matching transition layer is provided with Kevlar fiber sutures that run through the thickness direction. The Kevlar fiber sutures are evenly distributed in a mesh pattern. The bottom of the radome body is welded and fixed with an annular reinforcing base, and the annular reinforcing base is an aluminum alloy component.

[0006] As an improvement to the above technical solution, the hydrophobic and antifouling layer is a fluorine-modified epoxy resin-based composite material component, and the thickness of the hydrophobic and antifouling layer is 0.1-0.3mm, the static contact angle is ≥150°, and the roll-off angle is ≤10°.

[0007] As an improvement to the above technical solution, both the first skin layer and the second skin layer are quartz fiber cloth reinforced epoxy resin composite material components, and the thickness of both the first skin layer and the second skin layer is 0.8-1.5mm, the dielectric constant εᵣ=3.8±0.2, and the loss tangent tanδ<0.008.

[0008] As an improvement to the above technical solution, the total thickness of the gradient honeycomb core layer is 12-20mm, the outermost honeycomb pore diameter is 2-3mm, the innermost honeycomb pore diameter is 5-8mm, and the honeycomb wall of the gradient honeycomb core layer is made of glass fiber reinforced phenolic resin material with a thickness of 0.15-0.25mm.

[0009] As an improvement to the above technical solution, the impedance matching transition layer is a polytetrafluoroethylene composite material component, and the thickness of the impedance matching transition layer satisfies d=λ0 / (4√εᵣ), where λ0 is the center wavelength of the radar operating frequency band, εᵣ is the dielectric constant of the transition layer, and the dielectric constant εᵣ=2.2±0.1.

[0010] As an improvement to the above technical solution, the diameter of the Kevlar fiber suture is 0.3-0.5mm, the mesh spacing is 20-30mm, and the hot-pressing curing temperature of the Kevlar suture is the same as that of the gradient honeycomb core layer, which is 120-150℃.

[0011] The beneficial effects of this utility model are: By sequentially configuring a hydrophobic antifouling layer, a first skin layer, a gradient honeycomb core layer, an impedance matching transition layer, and a second skin layer on the radome body from the outside to the inside, and through the design of the impedance matching transition layer and the selection of low-loss skin materials, the transmittance is increased to ≥96%, and the multi-band insertion loss is <0.8dB, solving the reflection loss problem caused by the impedance abrupt change in the existing structure. The gradient honeycomb core layer combined with Kevlar fiber stitching improves the impact resistance of the radome and reduces the weight compared to traditional structures, meeting the surface accuracy requirements of ultra-large radomes. The hydrophobic antifouling layer enables pollutants to detach on their own, and the mesh stitching design effectively prevents crack propagation and extends the service life of the radome. Furthermore, all layers of materials are resistant to high and low temperatures (-55℃~125℃) and salt spray corrosion, making them suitable for radar systems in complex environments such as shipborne and airborne systems. Attached Figure Description

[0012] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a cross-sectional view of the radome body in this utility model; Figure 3 This utility model Figure 3 Enlarged structural diagram at point A in the middle; Figure 4 This is a structural diagram of the gradient honeycomb core layer in this utility model.

[0013] Reference numerals: 10, radome body; 11, hydrophobic and antifouling layer; 12, first skin layer; 13, gradient honeycomb core layer; 14, impedance matching transition layer; 15, second skin layer; 20, annular reinforcing base. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this utility model clearer, the following provides a more detailed description of the utility model. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the utility model.

[0015] Please see Figure 1-4 This utility model provides a technical solution: a multi-layer composite radar radome, including a radome body 10. The radome body 10 includes, from the outside to the inside, a hydrophobic and antifouling layer 11, a first skin layer 12, a gradient honeycomb core layer 13, an impedance matching transition layer 14, and a second skin layer 15. The hydrophobic and antifouling layer 11, the first skin layer 12, the gradient honeycomb core layer 13, the impedance matching transition layer 14, and the second skin layer 15 are tightly bonded together along the thickness direction and are solidified into a whole by hot pressing. The edges are sealed by laser welding. The gradient honeycomb core layer 13 is a closed-cell honeycomb structure. The honeycomb pore size of the gradient honeycomb core layer 13 increases in a stepwise manner from the side near the first skin layer 12 to the side near the impedance matching transition layer 14. Each of the first skin layer 12, the gradient honeycomb core layer 13, and the impedance matching transition layer 14 is provided with Kevlar fiber sutures that run through the thickness direction. The Kevlar fiber sutures are evenly distributed in a mesh. An annular reinforcing seat 20 is welded and fixed to the bottom of the radome body 10, and the annular reinforcing seat 20 is an aluminum alloy component.

[0016] In this embodiment, the radome body 10 is sequentially provided with a hydrophobic and antifouling layer 11, a first skin layer 12, a gradient honeycomb core layer 13, an impedance matching transition layer 14, and a second skin layer 15 from the outside to the inside. Through the design of the impedance matching transition layer 14 and the selection of low-loss skin materials, the transmittance is increased to ≥96%, and the multi-band insertion loss is <0.8dB, which solves the reflection loss problem caused by the impedance change in the existing structure. The gradient honeycomb core layer 13, combined with Kevlar fiber stitching, improves the impact resistance of the radome and reduces the weight compared to the traditional structure, meeting the surface accuracy requirements of ultra-large radomes. The hydrophobic and antifouling layer 11 enables pollutants to detach on their own. The mesh stitching design effectively prevents crack propagation and improves the service life of the radome.

[0017] Specifically, the hydrophobic and antifouling layer 11 is a fluorine-modified epoxy resin-based composite material component, and the thickness of the hydrophobic and antifouling layer 11 is 0.1-0.3 mm, with a static contact angle ≥150° and a roll-off angle ≤10°. In this embodiment, a fluorine-modified epoxy resin-based composite material with a thickness of 0.1-0.3 mm is used. Through the synergistic design of surface micro-nano structures and low surface energy materials, a superhydrophobic effect with a static contact angle ≥150° and a roll-off angle ≤10° is achieved. This allows rainwater and dust to roll off quickly, preventing pollutants from adhering and affecting wave transmittance. It also has UV resistance and anti-aging properties.

[0018] Specifically, the first skin layer 12 and the second skin layer 15 are both quartz fiber cloth reinforced epoxy resin composite material components, and the thickness of the first skin layer 12 and the second skin layer 15 are both 0.8-1.5mm, the dielectric constant εᵣ=3.8±0.2, and the loss tangent tanδ<0.008.

[0019] In this embodiment, quartz fiber cloth reinforced epoxy resin composite material with a thickness of 0.8-1.5mm is selected. This material has stable dielectric properties (εᵣ=3.8±0.2, tanδ<0.008), which can reduce electromagnetic wave attenuation and provide good structural support. The outer skin resists external impact, and the inner skin is close to the antenna side to ensure signal penetration efficiency.

[0020] Specifically, the total thickness of the gradient honeycomb core layer 13 is 12-20mm, the outermost honeycomb pore diameter is 2-3mm, the innermost honeycomb pore diameter is 5-8mm, and the honeycomb wall of the gradient honeycomb core layer 13 is made of glass fiber reinforced phenolic resin material with a thickness of 0.15-0.25mm. The diameter of the Kevlar fiber suture is 0.3-0.5mm, the mesh spacing is 20-30mm, and the hot pressing curing temperature of the Kevlar suture is the same as that of the gradient honeycomb core layer 13, which is 120-150℃.

[0021] In this embodiment, the gradient honeycomb core layer 13 has a total thickness of 12-20mm and adopts a closed-cell honeycomb structure. The outer layer of small-diameter honeycomb enhances the structural rigidity, while the inner layer of large-diameter honeycomb achieves lightweighting, balancing the requirements of strength and weight reduction. Kevlar fiber stitching is set in the layer, which can effectively prevent crack propagation after impact and improve the structure's damage resistance.

[0022] Specifically, the impedance matching transition layer 14 is a polytetrafluoroethylene composite material component, and the thickness of the impedance matching transition layer 14 satisfies d=λ0 / (4√εᵣ), where λ0 is the center wavelength of the radar operating frequency band, εᵣ is the dielectric constant of the transition layer, and the dielectric constant εᵣ=2.2±0.1.

[0023] In this embodiment, a polytetrafluoroethylene (PTFE) vinyl composite material with a dielectric constant εᵣ=2.2±0.1 is used, and its thickness is designed according to the quarter-wavelength impedance transformation principle (d=λ0 / (4√εᵣ)). This layer can alleviate the impedance abrupt change between the first skin layer and the gradient honeycomb core layer, reduce electromagnetic wave reflection loss, and improve the multi-band wave transmission stability. The above embodiments are only used to illustrate the technical solution of this utility model, and are not intended to limit it.

Claims

1. A multi-layered composite radar radome, comprising a radome body (10), characterized in that: The antenna radome body (10) includes, from the outside to the inside, a hydrophobic and antifouling layer (11), a first skin layer (12), a gradient honeycomb core layer (13), an impedance matching transition layer (14), and a second skin layer (15). The hydrophobic and antifouling layer (11), the first skin layer (12), the gradient honeycomb core layer (13), the impedance matching transition layer (14), and the second skin layer (15) are tightly bonded together along the thickness direction and are solidified into a whole by hot pressing. The edges are sealed by laser welding. The gradient honeycomb core layer (13) is a closed-cell honeycomb structure. The honeycomb pore size of the gradient honeycomb core layer (13) increases in a stepwise manner from the side near the first skin layer (12) to the side near the impedance matching transition layer (14). Each layer of the first skin layer (12), the gradient honeycomb core layer (13), and the impedance matching transition layer (14) is provided with Kevlar fiber sutures that penetrate along the thickness direction. The Kevlar fiber sutures are evenly distributed in a mesh. The bottom of the antenna radome body (10) is welded and fixed with an annular reinforcing seat (20), and the annular reinforcing seat (20) is an aluminum alloy component.

2. The radar radome with a multi-layer composite structure according to claim 1, characterized in that: The hydrophobic and antifouling layer (11) is a fluorine-modified epoxy resin-based composite material component, and the thickness of the hydrophobic and antifouling layer (11) is 0.1-0.3mm, the static contact angle is ≥150°, and the roll-off angle is ≤10°.

3. The radar radome with a multi-layer composite structure according to claim 1, characterized in that: The first skin layer (12) and the second skin layer (15) are both quartz fiber cloth reinforced epoxy resin composite material components, and the thickness of the first skin layer (12) and the second skin layer (15) is 0.8-1.5mm, the dielectric constant εᵣ=3.8±0.2, and the loss tangent tanδ<0.

008.

4. The radar radome with a multi-layer composite structure according to claim 1, characterized in that: The total thickness of the gradient honeycomb core layer (13) is 12-20mm, the outermost honeycomb pore diameter is 2-3mm, the innermost honeycomb pore diameter is 5-8mm, and the honeycomb wall of the gradient honeycomb core layer (13) is made of glass fiber reinforced phenolic resin material with a thickness of 0.15-0.25mm.

5. A multi-layer composite radar radome according to claim 1, characterized in that: The impedance matching transition layer (14) is a polytetrafluoroethylene composite material component, and the thickness of the impedance matching transition layer (14) satisfies d=λ0 / (4√εᵣ), where λ0 is the center wavelength of the radar operating frequency band, εᵣ is the dielectric constant of the transition layer, and the dielectric constant εᵣ=2.2±0.

1.

6. The radar radome with a multi-layer composite structure according to claim 1, characterized in that: The diameter of the Kevlar fiber suture is 0.3-0.5 mm, the mesh spacing is 20-30 mm, and the hot pressing curing temperature of the Kevlar fiber suture is the same as that of the gradient honeycomb core layer (13), which is 120-150℃.

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