Novel metasurface matching layer for ultra-wideband curved array antenna

Abstract

The invention discloses a novel metasurface matching layer for an ultra wide band curved surface array antenna, which comprises a curved surface supporting material layer, a dielectric substrate and a metasurface metal layer, and is characterized in that the dielectric substrate is bent and conformal on the curved surface supporting material layer, and the metasurface metal layer is arranged on the dielectric substrate; and a plurality of metasurface units are uniformly distributed on the metasurface metal layer. According to the novel metasurface matching layer, curved surface conformal can be realized, and the broadband impedance matching capability and the large-angle scanning performance of the ultra-wideband curved surface array antenna can be improved. According to the equivalent model theory of the novel metasurface matching layer, the novel metasurface matching layer provided by the embodiment of the invention can be equivalent to a dielectric layer with a high dielectric constant, the impedance matching of the antenna is improved, and compared with a common dielectric layer, the novel metasurface matching layer for the ultra-wideband curved surface array antenna provided by the embodiment of the invention has the advantages of light weight, low cost and the like. The cost is low, the processing is easy, and the development prospect is great.

Description

Technical Field

[0001] The present invention relates to the technical field of phased array antennas, and in particular to a novel metasurface matching layer for ultra-wideband curved array antennas. Background Art

[0002] A phased array antenna is an antenna that changes the shape of the radiation pattern by controlling the feeding phase of the radiating elements in the array antenna. The phased array antenna is composed of multiple antenna elements, and each array element (or a group of array elements) is connected to a controllable phase shifter. The relative feeding phase between the array elements is changed by controlling the size of the phase shift of these phase shifters, thereby changing the phase distribution of the electromagnetic waves on the antenna array surface, so that the beam scans in space according to a certain rule. If the amplitude and phase of the electromagnetic waves radiated by the antenna unit are accurately controlled, a highly directive antenna beam can be synthesized in space. When the amplitude and phase of the signal transmitted by each antenna unit channel are changed, the antenna beam can be quickly scanned and its shape changed. Compared with traditional mechanical scanning antennas, phased array antennas have the advantages of easy beam shaping, arbitrary change of beam direction, and easy formation of multiple beams.

[0003] Ultra-wideband phased array (UWB) technology combines the advantages of ultra-wideband technology and phased array technology. It uses ultra-wideband signals to transmit information and uses phased array technology to achieve beam pointing and shape control. By controlling the phase and amplitude of each antenna unit, the ultra-wideband phased array can form multiple beams in different directions, thereby achieving simultaneous tracking and measurement of multiple targets. Ultra-wideband phased arrays have attracted much attention in multi-functional applications. Ultra-wideband phased arrays have the advantages of high resolution, high precision, and strong anti-interference ability. They use multiple beams, polarizations, and frequency bands to achieve different functions. Existing planar array antenna technology can achieve a 10-fold frequency range by loading a planar matching layer technology. The introduction of the bending of the radiation structure will cause the antenna impedance characteristics to change, and the change is more significant at a large scanning angle. At this time, loading a planar matching layer will cause structural adaptation problems, and it will not be able to play the role of smoothing the impedance of the curved array port, resulting in a significant reduction in the working frequency band. Summary of the invention

[0004] The purpose of the present invention is to provide a new type of metasurface matching layer for an ultra-wideband curved array antenna to solve the technical problems existing in the prior art. The metasurface matching layer can achieve curved surface conformality and has the ability to improve the broadband impedance matching of the ultra-wideband curved array antenna.

[0005] The present invention is achieved through the following technical solutions:

[0006] A novel metasurface matching layer for an ultra-wideband curved array antenna provided by an embodiment of the present invention includes: a curved surface support material layer, a dielectric substrate, and a metasurface metal layer. The dielectric substrate is bent and conformal on the curved surface support material, and the metasurface metal layer is disposed on the dielectric substrate. A plurality of metasurface units are periodically arranged on the metasurface metal layer.

[0007] Further, the metasurface unit is a metasurface with a transverse sub-wavelength microstructure.

[0008] Further, the metasurface unit is a rectangular or square patch, and a cross-shaped slit is provided at the center of the rectangular or square patch.

[0009] Further, the metasurface unit is in the shape of an open-loop.

[0010] Further, the distance between adjacent metasurface units is 0.2 mm to 10 mm.

[0011] Further, the curved surface support material is a foam material or a Teflon material.

[0012] Further, the relative permittivity of the dielectric substrate is 1.05 to 5.

[0013] Further, the radius of curvature of the curved surface support material and the dielectric substrate is 0.1λ to 2λ.

[0014] Further, the thickness of the dielectric substrate is 0.5 mm to 2.2 mm.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0016] A novel metasurface matching layer for an ultra-wideband curved array antenna provided by an embodiment of the present invention realizes conformal shaping, and can improve the broadband impedance matching ability and large-angle scanning performance of the ultra-wideband curved array antenna. According to the equivalent model theory of the novel metasurface matching layer, the novel metasurface matching layer proposed by the embodiment of the present invention can be equivalent to a dielectric layer with a high dielectric constant, which improves the antenna impedance matching. Compared with a common dielectric layer, the novel metasurface matching layer for an ultra-wideband curved array antenna provided by the embodiment of the present invention has the advantages of light weight, low cost, easy processing, etc., and has great development prospects. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts. In the drawings:

[0018] Figure 1 Schematic diagram of a novel metasurface matching layer for an ultra-wideband curved array antenna provided by the first embodiment of the present invention;

[0019] Figure 2 Cross-sectional view of a novel metasurface matching layer for an ultra-wideband curved array antenna provided by the first embodiment of the present invention;

[0020] Figure 3 Top view of a novel metasurface matching layer for an ultra-wideband curved array antenna provided by the first embodiment of the present invention;

[0021] Figure 4 Equivalent relative permittivity curve graph of a novel metasurface matching layer for an ultra-wideband curved array antenna provided by the first embodiment of the present invention;

[0022] Figure 5 Equivalent relative permeability curve graph of a novel metasurface matching layer for an ultra-wideband curved array antenna provided by the first embodiment of the present invention;

[0023] Explanation of the reference numerals in the drawings:

[0024] 1 - Curved support material layer, 2 - Dielectric substrate, 3 - Metasurface metal layer, 4 - Metasurface unit. Detailed implementation manners

[0025] In the present invention, unless otherwise clearly specified and defined, terms such as "installed", "connected", "connected to", "fixed", etc. shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components or the interaction relationship between two components. The "first", "second" and similar terms mentioned in this application do not represent any order, quantity or importance, but are only used to distinguish different components. Similarly, terms such as "a" or "one" do not represent a quantity limit, but mean that there is at least one. In the implementation of this application, "and / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In the description of the embodiments of this application, unless otherwise stated, the meaning of "multiple" is two or more. For example, multiple positioning posts refer to two or more positioning posts. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0026] The embodiments of the present invention will be described in detail below.

[0027] Please refer to Figure 1-3, a novel metasurface matching layer for an ultra-wideband curved array antenna provided by the first embodiment of the present invention includes: a curved support material layer 1, a dielectric substrate 2, and a metasurface metal layer 3. The dielectric substrate 2 is bent and conformal to the curved support material 1, and the metasurface metal layer 3 is disposed on the dielectric substrate 2. A plurality of metasurface units 4 are periodically arranged on the metasurface metal layer 3.

[0028] The curved support material plays a crucial role in the ultra-wideband curved array antenna, mainly including: The curved support material serves as the substrate of the metasurface matching layer, which can provide stable physical support for the metasurface units, ensuring that they maintain the correct position and shape during the operation of the ultra-wideband curved array antenna, thereby ensuring the stable and reliable performance of the ultra-wideband curved array antenna. In practical applications, the curved support material needs to have sufficient strength and stiffness to withstand these external stresses, prevent the metasurface matching layer from deforming, being damaged or falling off, and thus ensure the normal operation of the ultra-wideband curved array antenna. The electromagnetic properties (such as dielectric constant, permeability, etc.) of the curved support material will affect the propagation of electromagnetic waves in the metasurface matching layer. By selecting a suitable curved support material, parameters such as the propagation speed, phase, and amplitude of electromagnetic waves can be adjusted, thereby optimizing the radiation pattern, gain, bandwidth, and other performance of the ultra-wideband curved array antenna. In the ultra-wideband curved array antenna, in order to improve the efficiency and gain of the ultra-wideband curved array antenna, it is necessary to minimize the reflection of signals between the ultra-wideband curved array antenna and the surrounding environment as much as possible. The curved support material can act as an impedance matching layer. By adjusting its electromagnetic properties, it can be matched with the impedance of the antenna and the surrounding environment, thereby reducing signal reflection and improving the radiation efficiency of the ultra-wideband curved array antenna. The curved support material needs to have good flexibility and processability, be able to conform to the shape of the curved object, and achieve conformal installation of the ultra-wideband curved array antenna and the curved object, thereby reducing the impact of the ultra-wideband curved array antenna on the aerodynamic performance and stealth performance of the curved object.

[0029] The dielectric substrate plays important roles such as physical support, signal conduction, and electromagnetic property regulation. As the carrier of the feeding network of the ultra-wideband curved array antenna, the dielectric substrate can transmit the radio frequency signals generated by the transmitter to the radiation elements of the ultra-wideband curved array antenna, and at the same time transmit the signals received by the ultra-wideband curved array antenna to the receiver. In the ultra-wideband curved array antenna, the dielectric substrate can also distribute the signals to each radiation element to realize beam formation and scanning. The electromagnetic characteristics such as the dielectric constant and magnetic permeability of the dielectric substrate will affect the propagation of electromagnetic waves in the ultra-wideband curved array antenna. By selecting a suitable dielectric substrate material, parameters such as the propagation speed, phase, and amplitude of electromagnetic waves can be adjusted, so as to optimize the performance of the ultra-wideband curved array antenna such as radiation pattern, gain, and bandwidth. The loss characteristics of the dielectric substrate will affect the efficiency and performance of the antenna. Selecting a low-loss dielectric substrate material can reduce the energy loss of the signal during transmission and improve the radiation efficiency of the antenna. The dielectric substrate can be used as an electromagnetic shielding material to suppress the electromagnetic interference inside and outside the ultra-wideband curved array antenna and improve the anti-interference ability of the ultra-wideband curved array antenna. The dielectric substrate in this embodiment is bent and conformal to the curved support material, realizing curved conformal.

[0030] A number of metasurface units are evenly distributed on the metasurface metal layer, which can improve the broadband impedance matching ability of the ultra-wideband curved array antenna. Specifically, the metasurface units can be equivalent to dielectric blocks with specific dielectric constants, magnetic permeabilities, and wave impedances. In this embodiment, by setting the shape, size, and arrangement of the metasurface units, their equivalent electromagnetic parameters are changed to better match the input impedance of the ultra-wideband curved array antenna in a wide frequency band and the characteristic impedance of free space, thereby reducing reflection and improving the transmission efficiency. The presence of the metasurface units can change the current distribution on the surface of the ultra-wideband curved array antenna. Reasonably designing the metasurface unit structure to make the current distribution on the surface of the ultra-wideband curved array antenna more uniform or distributed according to a specific pattern helps to reduce the change in the input impedance of the antenna and reduce the impedance mismatch phenomenon caused by uneven current distribution, thereby improving the broadband impedance matching ability. The metasurface units can suppress the propagation of surface waves in the antenna. Surface waves may cause energy loss during transmission or impedance mismatch. By suppressing surface waves, more energy can be transmitted along the desired path, improving the radiation efficiency and broadband impedance matching performance of the ultra-wideband curved array antenna.

[0031] In a novel metasurface matching layer for an ultra-wideband curved array antenna provided in another embodiment of the present invention, metasurface units 4 are periodically arranged on a metasurface metal layer 3, and the metasurface units 4 are metasurfaces with lateral sub-wavelength microstructures. These metasurfaces can flexibly control characteristics of electromagnetic waves such as polarization, amplitude, phase, polarization mode, and propagation mode. The structural units of this metasurface have characteristics of sub-wavelength scale in the lateral direction (i.e., the direction parallel to the surface). During actual application, the shapes, sizes, arrangement manners, and material characteristics of these microstructures can be set according to actual requirements to achieve various control effects on electromagnetic waves.

[0032] In a novel metasurface matching layer for an ultra-wideband curved array antenna provided in another embodiment of the present invention, there is a certain distance between adjacent metasurface units 4. The distance between adjacent metasurface units 4 is 0.2 mm to 10 mm. The selectable numerical range of the distance between adjacent metasurface units is wide, and appropriate values can be set according to actual situations.

[0033] By adjusting structural parameters such as the physical dimensions of the metasurface units, the required electromagnetic response is generated to achieve impedance matching with the ultra-wideband curved array antenna and the transmission line at different frequencies, and the matching frequency range is expanded. In a novel metasurface matching layer for an ultra-wideband curved array antenna provided in another embodiment of the present invention, the metasurface unit 4 can be a rectangular or square patch. A cross-shaped slot or a star-shaped slot is provided at the center of the rectangular or square patch. The size of the metasurface unit 4 is 20 mm × 20 mm. The distance between adjacent metasurface units 4 is 4 mm. The metasurface units 4 are arranged in a 7×15 periodic pattern on the curved surface. The width of the cross-shaped slot is 2.2 mm, and the length is 15.2 mm. The widths and lengths of the cross-shaped slot or the star-shaped slot can be adjusted to improve the performance of the metasurface matching layer. Shapes such as cross-shaped slots or star-shaped slots can improve the matching characteristics of the ultra-wideband curved array antenna, especially the matching characteristics for large-angle scanning. In this embodiment, the metasurface unit is a rectangular patch, and a cross-shaped slot is provided on the rectangular patch.

[0034] In a novel metasurface matching layer for an ultra-wideband curved array antenna provided in another embodiment of the present invention, the metasurface unit 4 can also be in the shape of a split ring. The metasurface unit 4 can also be made into various other shapes. Different types of shapes have different matching characteristics, and can be set into different shapes according to actual situations.

[0035] In a novel metasurface matching layer for an ultra-wideband curved array antenna provided in another embodiment of the present invention, the curved surface support material is a foam material or a Teflon material with a low dielectric constant.

[0036] When selecting the dielectric substrate, it is necessary to have good flexibility and processability, be able to conform to the shape of the curved object, and achieve conformal installation of the ultra-wideband curved array antenna and the curved object. In a novel metasurface matching layer for an ultra-wideband curved array antenna provided in another embodiment of the present invention, the relative permittivity of the dielectric substrate is 1.05 to 5. Preferably, a dielectric substrate with a relative permittivity of 2.2 is selected. The advantages of using a dielectric substrate with a relative permittivity of 2.2 are as follows: the signal propagation speed is faster, which can reduce the signal transmission delay, and it also helps to reduce the distortion and aberration of the signal during transmission, improve the signal quality, and can also reduce the energy loss during signal transmission, improve the signal transmission efficiency, and reduce signal attenuation.

[0037] In a novel metasurface matching layer for an ultra-wideband curved array antenna provided in another embodiment of the present invention, the thickness of the dielectric substrate is 0.5 mm to 2.2 mm. Preferably, a dielectric substrate with a thickness of 1.024 mm is selected.

[0038] In a novel metasurface matching layer for an ultra-wideband curved array antenna provided in another embodiment of the present invention, the curvature radii of the curved support material and the dielectric substrate are 0.1λ to 2λ. The advantages of setting the curvature radius of the dielectric substrate to 0.1λ to 2λ are as follows: it helps to make the current distribution and electromagnetic field distribution of the antenna more reasonable, thereby enhancing the gain of the antenna, enabling the signal to be transmitted farther and more clearly; it can achieve good impedance matching within a relatively wide frequency range, reduce signal reflection, improve signal transmission efficiency, and enable the antenna to work better in ultra-wideband applications; it keeps the impedance of the antenna relatively stable, ensuring that the antenna can have good performance under different working conditions.

[0039] In a novel metasurface matching layer for an ultra-wideband curved array antenna provided in another embodiment of the present invention, the thickness of the curved support material layer is 2 mm to 12 mm. Preferably, a curved support material with a thickness of 10 mm is selected.

[0040] The working principle of a novel metasurface matching layer for an ultra-wideband curved array antenna provided in an embodiment of the present invention is as follows: The metasurface matching layer can be used as a layer of high-permittivity material with a certain thickness. Since the relative permittivity of air is 1, the high-permittivity material can achieve a smooth transition from the antenna to free space and improve impedance matching. As Figure 4 、 5As shown, by adjusting the width \(d_s\) of the cross-shaped slot, the equivalent relative permittivity and equivalent permeability of the novel metasurface matching layer within a ten-fold frequency bandwidth in the UHF band are calculated according to the equivalent theory. Through simulation analysis, as the width \(d_s\) of the cross-shaped slot decreases, the equivalent relative permeability of the novel metasurface matching layer changes slightly, while the equivalent relative permittivity increases, which has a better improvement effect on the impedance matching of the antenna. However, resonance frequency points are likely to appear in the high-frequency band, and the width of the cross-shaped slot needs to be reasonably selected during actual use.

[0041] A novel metasurface matching layer for a ultra-wideband curved array antenna provided by an embodiment of the present invention realizes conformal shaping on the curved surface, and can improve the broadband impedance matching ability and large-angle scanning performance of the ultra-wideband curved array antenna. According to the equivalent model theory of the novel metasurface matching layer, the novel metasurface matching layer proposed in the embodiment of the present invention can be equivalent to a dielectric layer with a high dielectric constant, which improves the antenna impedance matching. Compared with ordinary dielectric layers, the novel metasurface matching layer for a ultra-wideband curved array antenna provided by the embodiment of the present invention has the advantages of being lightweight, low-cost, and easy to process, and has great development prospects.

[0042] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A novel metasurface matching layer for ultra-wideband curved array antenna, characterized in that: include: A curved surface supporting material layer, a dielectric substrate and a super surface metal layer, wherein the dielectric substrate is bent conformally on the curved surface supporting material, the super surface metal layer is arranged on the dielectric substrate, and a plurality of super surface units are periodically arranged on the super surface metal layer.

2. The novel metasurface matching layer for ultra-wideband curved array antenna according to claim 1, characterized in that: The metasurface unit is a metasurface with a lateral sub-wavelength microstructure.

3. The novel metasurface matching layer for ultra-wideband curved array antenna according to claim 1, characterized in that: The metasurface unit is a rectangular or square patch, and a cross-shaped gap is provided in the center of the rectangular or square patch.

4. The novel metasurface matching layer for ultra-wideband curved array antenna according to claim 1, characterized in that: The metasurface unit is in the shape of an open ring.

5. The novel metasurface matching layer for ultra-wideband curved array antenna according to claim 1, characterized in that: The distance between adjacent metasurface units is 0.2 mm to 10 mm.

6. The novel metasurface matching layer for ultra-wideband curved array antenna according to claim 1, characterized in that: The curved surface supporting material is foam material or Teflon material.

7. The novel metasurface matching layer for ultra-wideband curved array antenna according to claim 1, characterized in that: The relative dielectric constant of the dielectric substrate is 1.05-5.

8. The novel metasurface matching layer for ultra-wideband curved array antenna according to claim 1, characterized in that: The curvature radius of the curved surface support material and the dielectric substrate is 0.1λ to 2λ.

9. The novel metasurface matching layer for ultra-wideband curved array antenna according to claim 1, characterized in that: The thickness of the curved surface supporting material layer is 2 mm to 12 mm.

10. The novel metasurface matching layer for ultra-wideband curved array antenna according to claim 1, characterized in that: The thickness of the dielectric substrate is 0.5 mm to 2.2 mm.

Images