CN107394414B - Wave absorber for realizing low-frequency band bandwidth broadening based on double-layer magnetic medium - Google Patents
Wave absorber for realizing low-frequency band bandwidth broadening based on double-layer magnetic medium Download PDFInfo
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- CN107394414B CN107394414B CN201710584624.6A CN201710584624A CN107394414B CN 107394414 B CN107394414 B CN 107394414B CN 201710584624 A CN201710584624 A CN 201710584624A CN 107394414 B CN107394414 B CN 107394414B
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- 239000006096 absorbing agent Substances 0.000 title claims abstract description 54
- 239000002184 metal Substances 0.000 claims abstract description 48
- 229910052751 metal Inorganic materials 0.000 claims abstract description 48
- 239000000758 substrate Substances 0.000 claims abstract description 40
- 230000000737 periodic effect Effects 0.000 claims abstract description 34
- 239000000463 material Substances 0.000 claims description 12
- 238000010521 absorption reaction Methods 0.000 claims description 8
- 230000035699 permeability Effects 0.000 claims description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 3
- 239000011889 copper foil Substances 0.000 claims description 3
- 230000010287 polarization Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000002834 transmittance Methods 0.000 description 1
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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
- H01Q17/008—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems with a particular shape
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Abstract
The invention provides a wave absorber for realizing low-frequency bandwidth broadening based on double-layer magnetic media, which comprises a medium substrate (1), a metal plate (2) clung to the lower surface of the medium substrate (1), a periodic surface metal pattern (3) positioned on the upper surface of the medium substrate (1), a medium substrate (4) positioned on the periodic surface metal pattern, and a periodic surface metal pattern (5) positioned on the upper surface of the medium substrate (4).
Description
Technical Field
The invention relates to a wave absorber for realizing low-frequency band bandwidth broadening by a double-layer magnetic medium, belonging to the technical field of metamaterial wave absorber design.
Background
The microwave absorber is a functional material capable of effectively absorbing electromagnetic waves, in 2008, L andy and the like prepare an absorber with the wave absorbing performance close to 100% according to the electromagnetic resonance characteristics of a metamaterial, but the frequency band is very narrow, the development of the absorber is rapid, and with the continuous deepening of research, metamaterial absorber bodies with various polarization stabilities, wide incident angles, wide frequency bands and multiple frequency bands are proposed in succession and are applied to human body protection, information safety, target stealth, antenna radar scattering section reduction design and the like.
However, most of wave absorbers have working frequency in the X wave band at the present stage, the research on low-frequency wave absorbers with working frequency in the L frequency band is less, although the wave absorbers in the high frequency band can be scaled to the low frequency band by equal ratio, the thickness and the unit size are both extremely large, and under the premise of L frequency band and the thickness of the wave absorbing plate not exceeding 2mm, the wave absorption in a wider frequency band is difficult to realize.
Disclosure of Invention
The invention provides a wave absorber for realizing low-frequency band bandwidth broadening by a double-layer magnetic medium, and aims to provide a metamaterial wave absorber which is thin in thickness, low in frequency band, wide in bandwidth, insensitive to polarization and wide in incident angle and how to expand frequency bandwidth on the premise that the L frequency band and the thickness are not more than 2 mm.
The technical scheme is as follows: the wave absorber comprises a lower-layer medium substrate, a metal plate tightly attached to the lower surface of the medium substrate, a middle-layer periodic surface metal structure positioned on the upper surface of the lower-layer medium substrate, an upper-layer medium substrate positioned on the middle-layer periodic surface metal structure, and an upper-layer periodic surface metal structure positioned on the upper surface of the upper-layer medium substrate;
wherein:
the lower dielectric substrate is made of a material with the magnetic permeability reduced from 7.9 to 5.88 within a frequency range of 1GHz-2GHz, the dielectric constant is near 24, and the thickness is 0.6 +/-0.05 mm.
The upper dielectric substrate is made of materials, the magnetic permeability is reduced from 4.76 to 4.12 within the frequency range of 1GHz-2GHz, the dielectric constant is close to 16 but does not change greatly, and the thickness is 1.4 +/-0.05 mm.
The middle layer periodic surface metal structure and the upper layer periodic surface metal structure are both metal square ring structures, but have different sizes.
The side length of the outer ring of the square ring of the middle-layer periodic surface metal structure is 6.5 +/-0.1 mm, and the side length of the inner ring of the square ring is 0.6 +/-0.1 mm.
The side length of the outer ring of the square ring with the upper periodic surface metal structure is 7.6 +/-0.1 mm, and the side length of the inner ring of the square ring is 1.5 +/-0.1 mm.
The size of the wave absorber unit is (10 +/-0.1) mm, the thickness of the wave absorber is 2 +/-0.1 mm, and the metal plate, the middle-layer periodic surface metal structure and the upper-layer periodic surface metal structure are both copper foils and are 0.02 +/-0.005 mm.
The absorption rate of the wave absorber is calculated by a formula of A (omega) 1-R (omega), wherein R (omega) is the square of the module value of the input reflection coefficient of the wave absorber, and omega is frequency.
Has the advantages that:
1. the wave absorber for realizing low-frequency band bandwidth broadening based on the double-layer magnetic medium, disclosed by the invention, applies two different magnetic materials to a metamaterial wave absorber, and widens the bandwidth of the wave absorber with L frequency bands from the angle of a medium material through mutual matching between the two layers of magnetic media.
2. The wave absorber for realizing low-frequency band bandwidth broadening based on the double-layer magnetic medium is characterized in that periodic metal structures are attached to the surfaces of the two layers of the medium, and the impedance of the wave absorber can be adjusted easily by using the two layers of the metal structures.
3. The wave absorber for realizing low-frequency band bandwidth broadening based on the double-layer magnetic medium works in the L frequency band, and the wave absorber in the L frequency band at the present stage is less in design.
4. The wave absorber for realizing low-frequency band bandwidth broadening based on the double-layer magnetic medium has the advantages of thickness of 2mm, thinness, unit size of 10mm, small unit size and insensitivity to polarization.
Drawings
FIG. 1 is a schematic diagram of the overall structure of a low-band bandwidth broadening absorber based on a double-layer magnetic medium in the present invention,
FIG. 2 is a graph of the dielectric constant of the material used for the lower dielectric substrate of FIG. 1,
figure 3 is a graph of the permeability of the material used for the lower dielectric substrate of figure 1,
FIG. 4 is a graph of the dielectric constant of the material used for the upper dielectric substrate of FIG. 1,
figure 5 is a graph of the permeability of the material used for the upper dielectric substrate of figure 1,
figure 6 is a schematic diagram of a two layer periodic metal structure pattern of figure 1,
FIG. 7 is a wave absorption rate chart of example 1.
The figure shows that: the metal plate comprises a lower-layer dielectric substrate 1, a metal plate 2, a middle-layer periodic metal structure 3, an upper-layer dielectric substrate 4 and an upper-layer periodic metal structure 5.
Detailed Description
The invention relates to a wave absorber for realizing low-frequency bandwidth broadening based on a double-layer magnetic medium, which comprises a lower-layer medium substrate 1, a metal plate 2 tightly attached to the lower surface of the lower-layer medium substrate, a periodic surface metal structure 3 positioned on the upper surface of the lower-layer medium substrate 1, an upper-layer medium substrate 4 positioned on the periodic surface metal structure 3, and an upper-layer periodic surface metal structure 5 positioned on the upper surface of the upper-layer medium substrate 4.
Preferably, the lower dielectric substrate 1 is made of a material with magnetic permeability decreasing from 7.9 to 5.88 and dielectric constant being about 24 in a frequency range of 1GHz-2 GHz. The dielectric substrate 4 is made of a material, the magnetic permeability is reduced from 4.76 to 4.12 within a frequency range of 1GHz-2GHz, and the dielectric constant is close to 16 and does not change greatly.
Preferably, the middle-layer periodic metal structure 3 and the upper-layer periodic metal structure 5 are both metal square ring structures, but have different sizes, and the impedance of the whole wave absorber can be adjusted to be matched with the free space by adjusting the sizes of the patterns of the two layers of periodic metal structures.
Preferably, the metal plate 2 of the bottom layer, the periodic metal structures 3 of the middle layer and the periodic metal structures 5 of the upper layer are copper foils, and the thickness is 0.02 mm.
The absorption rate calculation formula of the wave absorber is generally as follows: here, since the metal plate 2 is used as the base layer, no wave is transmitted and the transmittance is zero, and the formula of the wave absorption rate in the present invention is a formula of a (ω) 1 to R (ω).
As exemplified below by what is encompassed by the claims.
Example 1:
a wave absorber for realizing low-frequency band bandwidth broadening based on a double-layer magnetic medium, as shown in figure 1. The periodic metal structure of the upper surfaces of the two layers of medium substrates is shown in fig. 6, the size of the wave absorber unit is 10mm x 10mm, the thickness of the lower layer of medium substrate is 0.6mm, the side length of the outer ring of the square ring on the surface of the lower layer of medium substrate is 6.5mm, and the side length of the inner ring of the square ring is 0.6 mm; the thickness of the upper medium substrate is 1.4mm, the side length of the outer ring of the square ring on the surface of the upper medium substrate is 7.6mm, and the side length of the inner ring of the square ring is 1.5 mm.
The wave absorber for realizing the low-frequency bandwidth broadening by the double-layer magnetic medium in the example is obtained by modeling and simulating HFSS.13 in electromagnetic simulation software, fig. 7 is a wave absorption rate curve chart in the example, and as can be seen from fig. 7, the wave absorber realizes the wave absorption rate of more than 0.85 at 1.25GHz-1.98GHz, so that the wave absorber realizes the bandwidth of more than 0.85 and 730MHz at the L frequency band.
In summary, the wave absorber for realizing low-frequency bandwidth broadening based on the double-layer magnetic medium can realize that the wave absorbing bandwidth with the wave absorbing rate of more than 0.85 is about 730MHz in the L frequency band, the thickness of the medium substrate is only 2mm, and the wave absorber is wide in bandwidth and thin in thickness and is beneficial to being applied to engineering practice.
Claims (6)
1. The utility model provides a wave absorber that realizes low frequency channel bandwidth broadening based on double-deck magnetic medium which characterized in that: the wave absorber comprises a lower-layer medium substrate (1), a metal plate (2) tightly attached to the lower surface of the lower-layer medium substrate (1), a middle-layer periodic surface metal structure (3) positioned on the upper surface of the lower-layer medium substrate (1), an upper-layer medium substrate (4) positioned above the middle-layer periodic surface metal structure (3), and an upper-layer periodic surface metal structure (5) positioned on the upper surface of the upper-layer medium substrate (4); the lower dielectric substrate (1) is made of a material within a frequency range of 1GHz-2GHz, and the upper dielectric substrate (4) is made of a material within a frequency range of 1GHz-2 GHz;
the magnetic permeability of the lower dielectric substrate (1) is reduced from 7.9 to 5.88, the dielectric constant is near 24, and the thickness is 0.6 +/-0.05 mm;
the magnetic permeability of the upper dielectric substrate (4) is reduced from 4.76 to 4.12, the dielectric constant is close to 16 but not greatly changed, and the thickness is 1.4 +/-0.05 mm.
2. The wave absorber of claim 1, wherein the double-layer magnetic medium is used for realizing low-frequency bandwidth broadening, and the wave absorber is characterized in that: the middle layer periodic surface metal structure (3) and the upper layer periodic surface metal structure (5) are both metal square ring structures, but have different sizes.
3. The wave absorber of claim 2, wherein the double-layer magnetic medium is used for realizing low-frequency bandwidth broadening, and the wave absorber is characterized in that: the side length of the outer ring of the square ring of the middle-layer periodic surface metal structure (3) is 6.5 +/-0.1 mm, and the side length of the inner ring of the square ring is 0.6 +/-0.1 mm.
4. The wave absorber of claim 2, wherein the double-layer magnetic medium is used for realizing low-frequency bandwidth broadening, and the wave absorber is characterized in that: the side length of the outer ring of the square ring of the upper-layer periodic surface metal structure (5) is 7.6 +/-0.1 mm, and the side length of the inner ring of the square ring is 1.5 +/-0.1 mm.
5. The wave absorber of claim 1, wherein the double-layer magnetic medium is used for realizing low-frequency bandwidth broadening, and the wave absorber is characterized in that: the size of the wave absorber unit is (10 +/-0.1) mm, the thickness of the wave absorber is 2 +/-0.1 mm, the metal plate (2), the middle-layer periodic surface metal structure (3) and the upper-layer periodic surface metal structure (5) are both copper foils, and the thickness is 0.02 +/-0.005 mm.
6. The wave absorber of claim 1, wherein the double-layer magnetic medium is used for realizing low-frequency bandwidth broadening, and the wave absorber is characterized in that: the absorption rate of the wave absorber is calculated by a formula of A (omega) 1-R (omega), wherein R (omega) is the square of the module value of the input reflection coefficient of the wave absorber, and omega is frequency.
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| CN109546352A (en) * | 2018-12-12 | 2019-03-29 | 浙江大学 | A kind of super matching absorbing material of the two waveband being made of secondary wavelength resonance structure |
| CN113054443B (en) * | 2021-03-23 | 2024-02-06 | 广东顺德西安交通大学研究院 | Low-frequency wave absorber |
| KR102599456B1 (en) * | 2022-02-25 | 2023-11-08 | 재단법인 파동에너지 극한제어 연구단 | Low frequency broadband absorber |
| CN114784520A (en) * | 2022-05-15 | 2022-07-22 | 南京理工大学 | Ultra-wideband transparent wave absorber with simple double-layer structure |
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