An L-band hyperboloidal skin conformal antenna unit

Abstract

This invention discloses an L-band hyperboloid skin conformal antenna element, comprising a radiating and feeding layer with a first preset curvature, a reflective layer with a second preset curvature, and an RF connector, wherein the first preset curvature is greater than the second preset curvature; the radiating and feeding layer includes a conformally configured broadband dipole radiator and a balun feed structure, the broadband dipole radiator being fitted to the inner side of the aircraft skin, one end of the balun feed structure being electrically connected to the broadband dipole radiator, and the other end being electrically connected to the RF connector; a honeycomb structure is provided between the radiating and feeding layer and the reflective layer. This invention designs a curved conformal (curvature 1) radiating and feeding layer and a curved conformal (curvature 2) reflective layer, which can broaden the operating frequency band, widen the elevation coverage airspace, eliminate traditional metal mounting beams and metal components, enhance strength, reduce weight, and achieve miniaturization / low profile.

Description

Technical Field

[0001] This invention relates to the field of conformal antenna technology, and more particularly to an L-band hyperboloid skin conformal antenna element. Background Technology

[0002] From a direct perspective of domestic and international aircraft development trends, new aircraft feature flat, thin, smooth, and streamlined curved shapes, blurring the traditional concepts of fuselage, wings, and tail. Furthermore, traditional antenna designs are no longer sufficient to meet the requirements of flat, smooth, streamlined, high-strength, low-weight, and miniaturized aircraft.

[0003] Antennas protruding from the fuselage of an aircraft are typically blade or whip antennas. Installing antennas inside the fuselage requires a radome, which protrudes from the fuselage to form a bulge. These traditional antennas can negatively impact aircraft characteristics. Therefore, improvements to traditional antennas are essential for new aircraft. Among these improvements, conformal antennas with skin have become an important research focus due to their high strength, low weight, miniaturization, and excellent aerodynamic performance.

[0004] Currently, most conformal antennas on airborne platforms use metal cavities or metal I-beams for mounting, which results in larger antenna size and weight, leading to higher installation costs. Furthermore, airborne conformal antennas typically have a radome that conforms to the skin, resulting in insufficient curvature of the antenna radiator itself. This leads to inadequate elevation coverage of the radiation pattern, creating blind spots for certain electronic systems.

[0005] Meanwhile, traditional airborne antennas, when fitted with a beam-type metal reflector, suffer from a narrow operating bandwidth due to the interference and superposition principle between the electromagnetic waves radiated by the antenna and those reflected by the metal reflector. This often fails to meet the requirements of electronic information systems. Summary of the Invention

[0006] To meet the wideband operating requirements of electronic information systems (two octaves, covering the L-band: 1–2 GHz), this invention proposes a conformal antenna design with a skin, achieving spatial coverage of elevation angles greater than ±60° within the band, miniaturization, and low weight. The design incorporates a conformal (curvature 1) radiation and feed layer and a conformal (curvature 2) reflector, which broadens the operating bandwidth and elevation coverage area. It eliminates traditional metal mounting beams and components, enhancing strength, reducing weight, and achieving miniaturization (low profile). Simultaneously, it achieves a VSWR ≤2 in the L-band (two octaves: 1–2 GHz) and 3 dB beam coverage in elevation angles greater than ±60°.

[0007] The technical solution adopted in this invention is as follows:

[0008] An L-band hyperboloid skin conformal antenna element includes a radiating and feeding layer with a first preset curvature, a reflective layer with a second preset curvature, and an RF connector, wherein the first preset curvature is greater than the second preset curvature; the radiating and feeding layer includes a conformally configured broadband dipole radiator and a balun feed structure, the broadband dipole radiator being fitted to the inner side of the aircraft skin, one end of the balun feed structure being electrically connected to the broadband dipole radiator, and the other end being electrically connected to the RF connector; a honeycomb structure is provided between the radiating and feeding layer and the reflective layer.

[0009] Furthermore, the broadband dipole radiator and the balun feed structure are highly integrated and manufactured by integral etching, with the radiator containing the feed structure and the feed structure containing the radiator.

[0010] Furthermore, the broadband dipole radiator and balun feed structure are formed by etching a metal film, which includes a polyimide metal film.

[0011] Furthermore, after the shape of the broadband dipole radiator is etched out from the polyimide metal film, it undergoes an anti-oxidation surface treatment and is then bonded to the inside of the skin with an adhesive film.

[0012] Furthermore, the radiation and feeding layer, through the form of double-layer film and hole edge alignment, in conjunction with the positioning of the radiator and the feed line, forms a broadband dipole radiator and a balun feeding structure.

[0013] Furthermore, a lightweight honeycomb structure is sandwiched between the radiation and feeding layer and the reflective layer, and cured by an adhesive film.

[0014] Furthermore, the surface of the reflective layer is metallized by attaching a metal film onto a conductive adhesive.

[0015] Furthermore, the conformal structure formed by the radiation and feeding layer and the reflective layer also includes a wedge structure.

[0016] The beneficial effects of this invention are as follows:

[0017] 1. The conformal antenna element of the present invention can achieve 3dB beam coverage in the elevation airspace greater than ±60°, and can significantly reduce the antenna size and weight.

[0018] 2. The conformal antenna element of the present invention has excellent performance and good broadband characteristics: such as a front-to-back ratio of more than 10dB and a voltage standing wave ratio of less than 2 within the frequency band.

[0019] 3. The conformal feeding form of the radiator-balun in the conformal antenna unit of the present invention solves the difficulties of conformal feeding of the skin, and has high structural strength and is easy to implement.

[0020] 4. The conformal antenna element of the present invention has a simple structure, light weight, low profile, high strength, and stable electrical performance, making it suitable for mass production. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of an L-band hyperboloid skin conformal antenna element according to an embodiment of the present invention.

[0022] Figure 2 This is a schematic diagram of the broadband dipole radiator and balun feed structure before and after conformal operation in an embodiment of the present invention. Detailed Implementation

[0023] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments are now described. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention; that is, the described embodiments are only a part of the embodiments of the invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] like Figure 1 As shown, this embodiment provides an L-band hyperboloid skin conformal antenna element, including a radiating and feeding layer with a first preset curvature, a reflective layer with a second preset curvature, and an RF connector. The first preset curvature is greater than the second preset curvature. The radiating and feeding layer includes a conformally configured broadband dipole radiator and a balun feed structure. The broadband dipole radiator is attached to the inner side of the aircraft skin. One end of the balun feed structure is electrically connected to the broadband dipole radiator, and the other end is electrically connected to the RF connector. Figure 1 As shown, a honeycomb structure is provided between the radiation and feeding layer and the reflective layer.

[0025] Currently, the height of a traditional dipole antenna is approximately 1 / 2 wavelength, while the broadband dipole radiator in this embodiment reduces the height to 1 / 4 wavelength by widening the oscillator, thereby reducing the antenna profile and facilitating platform installation.

[0026] like Figure 2 As shown, the broadband dipole radiator and balun feed structure are highly integrated and manufactured through integral etching. The broadband dipole radiator and balun feed structure do not require welding connections, thus transmitting the incident electromagnetic waves to the rear-end RF connector. Its advantage lies in its ability to withstand higher pressures in areas with large deformation during flight.

[0027] Preferably, the broadband dipole radiator and the balun feed structure are formed by etching a metal film. More preferably, the metal film can be a polyimide-based metal film. After the broadband dipole radiator is etched with the radiator shape from the polyimide metal film, it undergoes an anti-oxidation surface treatment and is then bonded to the inside of the skin using an adhesive film.

[0028] Preferably, a 0.5-1 mm cyanate ester is sandwiched between the two radiators of the broadband dipole radiator. The broadband dipole radiator is connected to the balun feed structure to form a radiation / feed layer. This structure is both the aircraft skin structure and the antenna radiation structure.

[0029] Preferably, in order to broaden the bandwidth and pitch beamwidth, the curvature and distance of the reflective layer are designed, and the surface of the reflective layer is metallized by attaching a metal film to the cyanate ester material to achieve the same reflective effect as a metal plate.

[0030] The curvature of the antenna reflector layer differs from that of the radiating and feeding layers; the radiating and feeding layers exhibit a higher degree of curvature compared to the reflector layer. A lightweight, high-strength honeycomb is sandwiched between the radiating and feeding layers and the reflector layer, and the two layers are cured together using an adhesive film.

[0031] In summary, the L-band hyperboloid skin conformal antenna element proposed in this embodiment is designed with a conformal (curvature 1) radiation and feed layer and a conformal (curvature 2) reflector, which can broaden the operating frequency band, widen the elevation coverage airspace, eliminate traditional metal mounting beams and metal components, enhance strength, reduce weight, and achieve miniaturization (low profile); at the same time, the VSWR is ≤2 in the L-band (two octaves: 1~2GHz), and 3dB beam coverage in the elevation airspace greater than ±60° is achieved.

[0032] It should be noted that, regarding the radiation and feeding layers involved in this embodiment, if the shape, size, etc. are not considered, radiators with other shapes, sizes, etc. can be used, and other feeding methods can also achieve the above functions.

[0033] It should be noted that the materials involved in this embodiment can be replaced depending on the different usage environments. For example, the cyanate ester-honeycomb-polyimide metal film material system can be replaced with other materials.

[0034] It should be noted that the hyperbolic shape structure involved in this embodiment can be replaced by a wedge or similar structure.

[0035] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. An L-band hyperboloid skin conformal antenna element, characterized in that, The system includes a radiating and feeding layer with a first preset curvature, a reflective layer with a second preset curvature, and an RF connector, wherein the first preset curvature is greater than the second preset curvature; the radiating and feeding layer includes a conformally configured broadband dipole radiator and a balun feeding structure, wherein the broadband dipole radiator is fitted to the inner side of the aircraft skin, and one end of the balun feeding structure is electrically connected to the broadband dipole radiator, and the other end is electrically connected to the RF connector; a honeycomb structure is provided between the radiating and feeding layer and the reflective layer; the broadband dipole radiator reduces its height to 1 / 4 wavelength by widening the oscillator.

2. The L-band hyperboloid skin conformal antenna element according to claim 1, characterized in that, The broadband dipole radiator and the balun feed structure are highly integrated and manufactured by integral etching. The radiator contains the feed structure, and the feed structure contains the radiator.

3. The L-band hyperboloid skin conformal antenna element according to claim 1, characterized in that, The broadband dipole radiator and balun feed structure are formed by etching a metal film, which includes a polyimide metal film.

4. The L-band hyperboloid skin conformal antenna element according to claim 3, characterized in that, The broadband dipole radiator is formed by etching the shape of the radiator from a polyimide metal film, then applying an anti-oxidation surface treatment, and finally attaching it to the inside of the skin with an adhesive film.

5. The L-band hyperboloid skin conformal antenna element according to claim 1, characterized in that, The radiation and feed layer, through double-layer film application and aperture edge alignment, combined with the positioning of the radiator and feed line, forms a broadband dipole radiator and balun feed structure.

6. The L-band hyperboloid skin conformal antenna element according to claim 1, characterized in that, A lightweight honeycomb structure is sandwiched between the radiation and feeding layer and the reflective layer, and is cured by an adhesive film.

7. The L-band hyperboloid skin conformal antenna element according to claim 1, characterized in that, The surface of the reflective layer is metallized by attaching a metal film onto conductive adhesive.

8. An L-band hyperboloid skin conformal antenna element according to any one of claims 1-7, characterized in that, The conformal structure formed by the radiation and feeding layer and the reflective layer also includes a wedge structure.

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