CN113629410B - Low-scattering reconfigurable slot antenna based on liquid - Google Patents
Low-scattering reconfigurable slot antenna based on liquid Download PDFInfo
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- CN113629410B CN113629410B CN202110518217.1A CN202110518217A CN113629410B CN 113629410 B CN113629410 B CN 113629410B CN 202110518217 A CN202110518217 A CN 202110518217A CN 113629410 B CN113629410 B CN 113629410B
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q21/00—Antenna arrays or systems
- H01Q21/06—Arrays of individually energised antenna units similarly polarised and spaced apart
- H01Q21/061—Two dimensional planar arrays
- H01Q21/064—Two dimensional planar arrays using horn or slot aerials
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
- H01Q1/364—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith using a particular conducting material, e.g. superconductor
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q17/00—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q21/00—Antenna arrays or systems
- H01Q21/0006—Particular feeding systems
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Abstract
The embodiment of the invention discloses a liquid-based low-scattering reconfigurable slot antenna, and relates to the technical field of radar detection. Specifically, the front side of the dielectric substrate is a slot antenna array, the back side of the dielectric substrate is a feed network, the surface of the slot antenna array is periodically provided with blocky water-based wave absorbers, the upper container is consistent with the water-based wave absorbers arranged on the upper surface of the slot antenna array, the upper container and the water-based wave absorbers form a closed structure, a water layer is filled in the closed structure, and the antenna is a metal backboard. According to the invention, the slot array antenna is combined with the water-based wave absorber, the liquid-based low-scattering reconfigurable antenna is constructed by utilizing the high loss and fluidity of water, and good impedance matching is realized, so that the low-scattering and RCS reconfigurable performance of the antenna is achieved on the premise of ensuring the radiation performance of the slot array antenna. The invention is based on the research of the dispersion characteristic of water, and the low scattering and RCS reconfigurable performance of the antenna is obtained by pumping in and pumping out the water.
Description
Technical Field
The invention relates to the technical field of radar detection, in particular to a low-scattering reconfigurable slot antenna based on liquid.
Background
With the development of detection technology and stealth technology, radar Cross Section (RCS) reduction of a platform target has great military significance. RCS reduction of antenna systems on platforms has become a bottleneck restricting platform stealth. Compared with the platform, the scattering property of the platform can be obviously improved by changing the shape of the platform and mounting the wave absorbing material on the surface, and the antenna is used as a special scattering body, so that the RCS is reduced and the radiation performance requirement of the antenna is required to be met.
In recent years, artificial metamaterials are applied to RCS reduction of antennas, for example, a band-pass frequency selective absorber is used as an antenna housing, so that electromagnetic waves in the band of the antenna can be radiated, and out-of-band electromagnetic waves can be absorbed, thereby realizing RCS reduction of the antenna. But this method easily causes the radome to heat up, thereby affecting the operational performance of the antenna. By using the zero reflection phase characteristic of an Artificial Magnetic Conductor (AMC), the reflection wave phase difference is 180 by properly arranging the AMC around the antenna. Thereby achieving the purpose of cancellation.
The disadvantage of this approach is that only a single station RCS reduction in one direction can be achieved, resulting in an increase in RCS in the other direction. While the RCS of most antennas is shrinking, although stealth is achieved for enemy detection, there is also some difficulty for own detection.
Disclosure of Invention
The embodiment of the invention provides a water-based low-scattering reconfigurable slot antenna, wherein the inner parts of middle water layers of unit structures are communicated everywhere, so that a high-loss resonant cavity is formed, and the wide-frequency-band wave absorbing performance based on liquid is realized.
In order to achieve the above purpose, the embodiment of the present invention adopts the following technical scheme:
The multi-layer structure comprises an upper container (1), a slot antenna array (3), a dielectric substrate (4) and a metal back plate (6) in sequence from high to low according to the hierarchy, wherein the slot antenna array (3) is paved on the front surface of the dielectric substrate (4), a feed network (5) is paved on the back surface of the dielectric substrate (4), the slot structures are formed behind the upper container (1), the slot structures are arranged in a matrix, the upper container (1) is installed and attached to the slot antenna array (3), each slot structure and the attached slot antenna array (3) form a cavity, a diversion hole is formed between one slot structure and at least one other adjacent slot structure so that liquid can flow between one slot structure and at least one other adjacent slot structure, after the liquid fills all the cavities, block water is formed in each cavity, a middle block water layer (2) is obtained, and all block water in the middle block water layer (2) is arranged according to the matrix. The liquid material adopted by the middle water layer (2) is pure water with electromagnetic parameters meeting the Debye model.
The cavities are 5mm long and wide l w mm thick, h w and 4mm spacing between adjacent cavities in the matrix. The slot length I of the slot antenna array (3) is 33.2mm, the width w is 3mm, the array element spacing d is 30mm, and the working frequency band of the slot antenna array (3) is close to 3.1GHz.
The dielectric substrate (4) was made of an FR4 dielectric material having a relative permittivity of 4.3 and a loss tangent of 0.025. The length L of the dielectric substrate (4) is 220mm, the width W is 110mm, and the thickness is 1mm. The upper container (1) was made of an acryl material having a dielectric constant of 2.67 and a loss tangent of 0.01.
The low-scattering reconfigurable slot antenna based on water provided by the embodiment of the invention has the advantages that the front surface of a dielectric substrate is provided with a slot antenna array, the back surface of the dielectric substrate is provided with a feed network, the surface of the slot antenna array is periodically provided with block-shaped water-based wave absorbers, an upper container and the water-based wave absorbers arranged on the upper surface of the slot antenna array are kept consistent, a closed structure is formed by the upper container and the water-based wave absorbers, a water layer is filled in the closed structure, and the back of the antenna is provided with a metal backboard. According to the invention, the slot array antenna is combined with the water-based wave absorber, the liquid-based low-scattering reconfigurable antenna is constructed by utilizing the high loss and fluidity of water, and good impedance matching is realized, so that the low-scattering and RCS reconfigurable performance of the antenna is achieved on the premise of ensuring the radiation performance of the slot array antenna.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments provided by the embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic diagram of a back-layering of a liquid-based low-scattering RCS reconfigurable antenna according to an embodiment of the present invention;
Fig. 2 is a schematic diagram of a feed network according to an embodiment of the present invention;
FIG. 3 shows a water-based absorber unit structure according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of forward layering of a liquid-based low scattering RCS reconfigurable antenna according to an embodiment of the present invention;
FIG. 5 is a single station RCS diagram of a liquid-based low scattering antenna provided by an embodiment of the invention;
FIG. 6 is a diagram of a dual station RCS of a liquid-based low scattering antenna provided by an embodiment of the invention;
FIG. 7 is an E-plane radiation pattern of a liquid-based low-scattering antenna according to an embodiment of the present invention;
fig. 8 is an H-plane radiation pattern of a liquid-based low scattering antenna according to an embodiment of the present invention.
Fig. 9 is a Debye model plot of water provided by an embodiment of the present invention.
Fig. 10 is an S-parameter curve of an antenna according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail below with reference to the drawings and detailed description for the purpose of better understanding of the technical solution of the present invention to those skilled in the art. Embodiments of the present invention will hereinafter be described in detail, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for explaining the present invention and are not to be construed as limiting the present invention. As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless expressly stated otherwise, as understood by those skilled in the art. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may also be present. Further, "connected" or "coupled" as used herein may include wirelessly connected or coupled. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items. It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Radar cross-sectional area (RCS) is a physical quantity that defines the scattering characteristics of a target, which exhibits an equivalent scattering area upon irradiation with an incident radar wave. The traditional RCS reduction includes four steps of shaping technology, wave absorbing material coating, passive cancellation and active cancellation. Among them, the shaping technology is often struggling with the RCS characteristics of the platform itself, and it is difficult to change its shape because the antenna needs to guarantee its radiation characteristics. The problem with applying the absorbing material is that after the absorbing material absorbs energy, it increases in temperature itself, and if the scattering is not kept up, the change in temperature can change the electrical performance of the device. Passive cancellation and active cancellation are not applied more than the former two for technical difficulties and costs.
The existing disadvantage is that only a single station RCS reduction in one direction can be achieved, resulting in an increase in RCS in the other direction. While the RCS of most antennas is shrinking, although stealth is achieved for enemy detection, there is also some difficulty for own detection. The invention aims to provide a low-scattering and RCS reconfigurable slot antenna, which overcomes the problems in the prior art, and relates to a water-based low-scattering and reconfigurable slot antenna, in particular to a low-scattering and reconfigurable slot antenna composed of high-loss media and applicable to stealth detection.
The low-scattering reconfigurable slot antenna is provided by utilizing the most extensive resource-water on the earth, namely the high loss, the fluidity and the self heat dissipation performance, and compared with the traditional structure, the low-scattering reconfigurable slot antenna has the advantages of saving cost, being simple to prepare and realizing the low-scattering and RCS reconfigurable performance.
The embodiment of the invention provides a liquid-based low-scattering reconfigurable slot antenna, which sequentially comprises an upper container (1), a slot antenna array (3), a dielectric substrate (4) and a metal back plate (6) from top to bottom according to the sequence of the layers, wherein the slot antenna array (3) is paved on the front surface of the dielectric substrate (4), and a feed network (5) is paved on the back surface of the dielectric substrate (4). The specific layout structure of the feed network (5) may be shown in fig. 2, where the feed network (5) is composed of wires arranged in an H-shape, and wires connected to the H-shape structure. The feed network (5) is followed by a metal back plate (6) of the antenna.
As shown in fig. 1, the back of the upper container (1) is provided with a groove structure, the groove structures are arranged in a matrix, the upper container (1) is mounted and attached to the slot antenna array (3), and each groove structure and the attached slot antenna array (3) form a cavity. And a diversion hole is formed between one groove structure and at least one other adjacent groove structure so that liquid can flow between the groove structure and the at least one other adjacent groove structure, after the liquid is filled in all the cavities, massive water is formed in each cavity to obtain a middle massive water layer (2), and all the massive water in the middle massive water layer (2) is arranged according to the matrix.
In a preferred version of this embodiment, as shown in fig. 3, the cavities are 5mm long and wide lw, 5mm thick hw, and 4mm spacing between adjacent cavities in the matrix. The slot length I of the slot antenna array (3) is 33.2mm, the width w is 3mm, the array element spacing d is 30mm, and the working frequency band of the slot antenna array (3) is close to 3.1GHz.
In a preferred embodiment of the present invention, the dielectric substrate (4) is made of an FR4 dielectric material having a relative permittivity of 4.3 and a loss tangent of 0.025. The length L of the dielectric substrate (4) is 220mm, the width W is 110mm, and the thickness is 1mm. The upper container (1) was made of an acryl material having a dielectric constant of 2.67 and a loss tangent of 0.01.
In a preferred embodiment of the present embodiment, the intermediate water layer (2) shown in fig. 9 uses a liquid material that is pure water whose electromagnetic parameters satisfy the Debye model. The liquid material used in this embodiment is not limited to this, and other liquid materials such as alcohol and acetone may be used. The intermediate water layer (2) is filled between the upper containers (1), and due to the special electromagnetic property of water, when two states of water filling and draining change, the low-scattering reconfigurable slot antenna presents unique electromagnetic performance of 'unchanged radiation performance, reconfigurable RCS', and is more fit for 'intelligent' selection in a stealth system.
The invention designs a low-scattering RCS reconfigurable slot antenna, which comprises an upper container (1), a middle water layer (2), a dielectric substrate (4), a slot antenna array (3) on the front side of the dielectric substrate, a feed network (5) on the back side of the dielectric substrate and a metal backboard (6), wherein the upper container (1) and an arranged water-logging wave absorber are kept consistent, so that a closed structure is formed, and the middle blocky water layer (2) is filled in the closed structure.
The present embodiment contemplates a liquid-based low scattering reconfigurable slot antenna. The front side of the medium substrate is provided with a slot antenna array, the back side of the medium substrate is provided with a feed network, the surface of the slot antenna array is periodically provided with blocky water-based wave absorbers, the upper container is consistent with the water-based wave absorbers arranged on the upper surface of the slot antenna array, the upper container and the water-based wave absorbers form a closed structure, a water layer is filled in the closed structure, and the antenna is provided with a metal backboard. According to the invention, the slot array antenna is combined with the water-based wave absorber, the liquid-based low-scattering reconfigurable antenna is constructed by utilizing the high loss and fluidity of water, and good impedance matching is realized, so that the low-scattering and RCS reconfigurable performance of the antenna is achieved on the premise of ensuring the radiation performance of the slot array antenna. The invention is based on the research of the dispersion characteristic of water, and the low scattering and RCS reconfigurable performance of the antenna is obtained by pumping in and pumping out the water.
In this embodiment, the radiation pattern of the antenna is shown in fig. 7-8, the single station RCS of the antenna is shown in fig. 5, the broadband RCS reduction of 4GHz to 18GHz is realized, and the dual station RCS of the antenna is shown in fig. 6. Therefore, in the overall structural design, the low scattering and RCS reconfigurable performance of the antenna are realized, and meanwhile, the requirements of good impedance matching and antenna radiation performance are met.
As can be seen from the experimental results of fig. 5-10, in this embodiment, by performing the periodic arrangement of the broadband wave absorbing based on liquid in the horizontal and vertical directions, the mobility of water is utilized, so that the internal communication of the middle massive water layer (2) of the unit structure is ensured, a high-loss resonant cavity is formed, and the broadband wave absorbing performance based on liquid is realized. Wherein, 4 slots are formed through the upper container (1) and the slot positions of the slot antenna array (3) are kept consistent, so that the radiation performance of the antenna array is ensured.
The broadband wave absorber is formed through the high-loss performance of water, and the out-of-band RCS reduction of the single station and the double station of the antenna is realized by combining a slot antenna. Through the flow property of water, the reconfigurable performance of the antenna RCS is realized through the water sucking and sucking process. And the band performance can be satisfied, the broadband RCS reduction from 4GHz to 18GHz can be realized out of band, and the good radiation performance in the band is ensured.
In this specification, each embodiment is described in a progressive manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment mainly describes differences from other embodiments. In particular, for the apparatus embodiments, since they are substantially similar to the method embodiments, the description is relatively simple, and reference is made to the description of the method embodiments for relevant points. The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the scope of the present invention should be included in the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.
Claims (6)
1. The low-scattering reconfigurable slot antenna based on liquid is characterized by sequentially comprising an upper container (1), a slot antenna array (3), a dielectric substrate (4) and a metal back plate (6) from high to low according to the hierarchy, wherein the slot antenna array (3) is paved on the front surface of the dielectric substrate (4), and a feed network (5) is paved on the back surface of the dielectric substrate (4);
The back of the upper container (1) is provided with a groove structure, the groove structures are arranged in a matrix, the upper container (1) is mounted and attached to the slot antenna array (3), and each groove structure and the attached slot antenna array (3) form a cavity;
a diversion hole is formed between one groove structure and at least one other adjacent groove structure so that liquid can flow between the groove structure and the at least one other adjacent groove structure, after the liquid fills all cavities, massive water is formed in each cavity to obtain a middle massive water layer (2), and all massive water in the middle massive water layer (2) is arranged according to the matrix;
The feed network (5) consists of H-shaped wires and wires connected with the H-shaped structure, wherein the metal backboard (6) of the antenna is arranged behind the feed network (5);
The liquid material adopted by the middle water layer (2) is alcohol or acetone with electromagnetic parameters meeting the Debye model.
2. The liquid based low scattering reconfigurable slot antenna of claim 1,
The cavities are 5mm long and wide l w mm thick, h w and 4mm spacing between adjacent cavities in the matrix.
3. The liquid based low scattering reconfigurable slot antenna of claim 1, wherein the slot length I of the slot antenna array (3) is 33.2mm, the width w is 3mm, the array element spacing d is 30mm, and the operating band of the slot antenna array (3) is close to 3.1GHz.
4. The liquid-based low scattering reconfigurable slot antenna of claim 1, wherein the dielectric substrate (4) is an FR4 dielectric material having a relative permittivity of 4.3 and a loss tangent of 0.025.
5. The liquid based low scattering reconfigurable slot antenna of claim 4, wherein the length L of the dielectric substrate (4) is 220mm, the width W is 110mm, and the thickness is 1mm.
6. The liquid-based low scattering reconfigurable slot antenna of claim 1, wherein the upper container (1) is made of an acryl material having a dielectric constant of 2.67 and a loss tangent of 0.01.
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| CN114744414B (en) * | 2022-03-18 | 2025-08-29 | 南京航空航天大学 | A system for adjusting a frequency selective absorber |
| CN115911884B (en) * | 2022-10-18 | 2025-11-21 | 南京理工大学 | Liquid-based reconfigurable wave absorber with broadband wave-transparent window |
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| CN216214140U (en) * | 2021-05-12 | 2022-04-05 | 南京航空航天大学 | Low-scattering reconfigurable slot antenna based on water |
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| CN102227040A (en) * | 2011-03-04 | 2011-10-26 | 西安电子科技大学 | Array Antennas for Radar Cross Section Reduction |
| WO2013126124A2 (en) * | 2011-12-07 | 2013-08-29 | Utah State University | Reconfigurable antennas utilizing liquid metal elements |
| CN106025511A (en) * | 2016-06-20 | 2016-10-12 | 中国电子科技集团公司第三十八研究所 | Low-profile conformal antenna |
| CN109687104B (en) * | 2018-12-20 | 2024-03-01 | 中国科学院上海微系统与信息技术研究所 | Wide-horizontal angle and narrow-pitch angle single-slit antenna and manufacturing method thereof |
| CN109509989A (en) * | 2019-01-11 | 2019-03-22 | 南京航空航天大学 | A kind of heat adjustable frequency selection wave-absorber based on water |
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| Title |
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| A Slot Antenna Array With Reconfigurable RCS Using Liquid Absorber;Yukun Zou et al;《IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION》;20220731;全文 * |
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