CN107706538B - A kind of dissipative type wide-band and wave-absorbing FSS structure and preparation method - Google Patents
A kind of dissipative type wide-band and wave-absorbing FSS structure and preparation method Download PDFInfo
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- CN107706538B CN107706538B CN201610642521.6A CN201610642521A CN107706538B CN 107706538 B CN107706538 B CN 107706538B CN 201610642521 A CN201610642521 A CN 201610642521A CN 107706538 B CN107706538 B CN 107706538B
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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 present invention proposes a kind of dissipative type wide-band and wave-absorbing FSS structure and preparation method, using carbon film spraying process on dielectric-slab molding patch-type FSS cellular construction, the FSS cellular construction is the square of fractal structure, using square grid periodic arrangement；The square of the fractal structure includes the well word structure patch at center and the big square patch positioned at square quadrangle, squarely prong like is expanded in the end of four arms of the well word structure patch, arranges small square patch in rectangular prong like internal symmetry.The special FSS structure of the present invention, its sheet resistance characteristic having breaches the characteristic that legacy frequencies select surface stopband as total reflection, introduce the dissipative network of capacitor, inductance, resistance and transmission line composition, stopband frequency range can effectively be reduced, the application for solving existing frequency-selective surfaces is limited to the technical problem of construction profile.
Description
Technical field
The present invention relates to a kind of dissipative type wide-band and wave-absorbing FSS structure and preparation methods, belong to Electromagnetic Field and Microwave Technology
Field.
Background technique
While development with modern military technology high-speed, the aircraft wave transparent/stealth technology come into being is also at various countries
The focus and emphasis of research.Frequency-selective surfaces (FSS) are a kind of spatial electromagnetic filter structures, can special frequency channel make electromagnetism without
Loss or low-loss pass through, and filter the electromagnetic wave outside the frequency range.FSS technology is constantly subjected to height after being suggested from its concept
Degree is paid attention to, and such as the technology is applied on aircraft radars cover, can be realized our radar and works normally, enemy radar is worked
The reflection of electromagnetic wave of frequency range reduces radar cross section to other directions, thus FSS is to realize aircraft wave transparent/stealth technology
Important measures.
FSS structural unit types can be divided into two classes: fluting type, patch type.Two types are complementary, but the two has
There is opposite frequency response characteristic.From the perspective of equivalent circuit method, shaped grooved FSS is the parallel circuit of LC, be can be used for
Band logical design；And patch type is then opposite.
In terms of FSS structural unit, common structure type can be divided into 4 kinds.1st kind: center connecting-type, it is such as simplest
Straight line units, three pole subelements, anchor unit, Jerusalem cross-shaped element, square spiral unit；2nd kind: annular element,
Such as three legs and four leg loading units and annulus, Fang Huan and hexagonal rings；3rd kind: solid unit or board-like list of various shapes
Member；4th kind: assembled unit.
Traditional sucrose radome can be realized ship mast antenna low-frequency range high wave transparent requirement, but X-band not
There is stealth effect.In wave transparent/Stealthy reflector Antenna cover electrical property design, using reflection-type frequency-selective surfaces (FSS) technology,
The cellular construction generallyd use is one of above four kinds of forms, is processed using metal patch, and this FSS technology is applicable in
In the antenna house of Stealth shape, principle is the RCS that reflection of electromagnetic wave is reduced to antenna house to other orientation, for non-low
The antenna house of RCS shape, such as the oval antenna house of tangent, elliptical antenna cover and hemispherical antenna house type, the technology is not
It is applicable in, it is difficult to reduce the RCS of antenna house.Therefore, it in the radome electrical property of non-low RCS shape can design, need to be inhaled using having
The dissipative type FSS structure of wave effect, such structure are abandoned the form processing of metal patch, are processed into using the carbon film with sheet resistance
Structural unit generallys use square patch or strip patch form in structure type, surface capacitive reactances is formed, to reach suction
Wave effect.But existing carbon film is processed into structural unit, is unable to satisfy in HF/VHF wave band and inhales wave by force in high wave transmission rate and X-band
The requirement of performance.Therefore, need one kind be able to satisfy in HF/VHF wave band wave transmission rate be greater than 90%, X-band internal reflection rate be less than-
The dissipative type wide-band and wave-absorbing FSS structure and preparation method of 20dB.
Summary of the invention
It is an object of the invention to overcome the shortage of prior art, one kind high wave transmission rate (wave transparent in HF/VHF wave band is provided
90%) rate is greater than, wave transparent/stealthy function integration dissipative type of strong absorbing property (reflectivity is less than -20dB) in X-band
Wide-band and wave-absorbing FSS structure and preparation method.
Technical solution of the invention: a kind of dissipative type wide-band and wave-absorbing FSS structure is being situated between using carbon film spraying process
Molding patch-type FSS cellular construction on scutum, the FSS cellular construction is the square of fractal structure, using square
Grid cycle arrangement；
The square of the fractal structure includes the well word structure patch at center and the big pros positioned at square quadrangle
Squarely prong like is expanded in the end of shape patch, four arms of the well word structure patch, in rectangular prong like
Portion is arranged symmetrically small square patch, and the height H of rectangular prong like is consistent with big square patch side length a, small square patch
The outer side edges of piece are overlapped with the side of the square of fractal structure, the gap, big square patch between well word structure patch arm
The gap between gap b and small square patch and rectangular prong like between rectangular prong like is wide.
The big square patch side length a=4b~6b, the small square patch side length c=2b~3b, it is described
Well word structure patch four wide d=0.8b~1.2b of arm.
The FSS cellular construction side length L=10b~20b.
The value range of the gap b is 0.1mm~0.5mm.
The carbon film thickness of the FSS cellular construction is 0.01mm~0.02mm.
The gap b etc. between gap and big square patch and rectangular prong like between the square grid
It is wide.
FSS structure of the invention uses square patch in well word structural perimeter, plays the work for effectively inhibiting parasite current
With, while there is preferable angle stability and polarizer stability, well word structure end expands squarely prong like, and in side
Shape prong like intermediate arrangement square patch adjusts patch as impedance, plays adjusting hindrance function.Entire patch uses carbon film
Spraying process molding, has certain sheet resistance.The structure of patch of the present invention and special structure proportion relationship and antenna house
Cover material matches, to realize that stealthy frequency range inhales by force the effect of wave in the high wave transparent of Antenna Operation frequency range.
A kind of dissipative type wide-band and wave-absorbing FSS structure preparation method, is realized by following steps:
Conductive carbon black is evenly applied on processing release paper with doctor knife coater, carbon film plate is made by the first step；
Realize control to carbon film sheet resistance by control coating layer thickness, carbon film thickness be generally 0.01mm~
0.02mm.Specific carbon film spraying process is techniques well known, is not just repeated one by one herein.
FSS cellular construction is arranged in by second step, shape needed for the carbon film plate prepared is cut into FSS cellular construction
In medium substrate, the FSS cellular construction is the square of fractal structure, well word structure patch including center and is located at just
Squarely prong like is expanded in the end of the big square patch of rectangular quadrangle, four arms of the well word structure patch,
Small square patch, the height H of rectangular prong like and big square patch side length a are arranged in rectangular prong like internal symmetry
Unanimously, the outer side edges of small square patch are overlapped with the side of the square of fractal structure, the seam between well word structure patch arm
The seam between gap b and small square patch and rectangular prong like between gap, big square patch and rectangular prong like
Gap is wide.
Carbon film plate is cut out to be cut out using laser cutting machine.
The present invention compared with prior art the utility model has the advantages that
(1) the special FSS structure of the present invention, the sheet resistance characteristic having breach legacy frequencies selection surface stopband
For the characteristic of total reflection, the dissipative network of capacitor, inductance, resistance and transmission line composition is introduced, stopband frequency range can be carried out effective
Decrement, the application for solving existing frequency-selective surfaces are limited to the technical problem of construction profile；
(2) present invention uses square patch in well word structural perimeter, and parasite current can be effectively suppressed, and plays choking effect, well
The patch of font distribution has preferable angle stability and polarizer stability, can meet within the scope of wide angular domain that (0~60 ° enters
In elevation range) there are high wave transmission rate and strong wave-sucking performance, well word structure end expands squarely prong like, in rectangular forked knot
Structure intermediate arrangement square patch adjusts patch as impedance, adjusting hindrance function is played, to meet antenna house in Practical Project
Upper application；
(3) the proportionate relationship cooperation between special construction of the present invention and structure realizes the high wave transmission rate in HF/VHF wave band
(wave transmission rate is greater than 95%), the characteristic of strong absorbing property (reflectivity is less than -20dB), solves non-low RCS shape in X-band
The stealthy problem of antenna house low frequency wave transparent, high frequency；
(4) present invention can apply to the designs of many kinds of radar cover structures such as single layer, A interlayer, B interlayer, C interlayer, to meet not
Same design requirement.
Detailed description of the invention
Fig. 1 is FSS structural unit schematic diagram of the present invention；
Fig. 2 is using stealth radar cover structure schematic diagram of the invention, wherein 4 be antenna house cover, 5 be dissipative type FSS
Substrate, 6 be dissipative type FSS film, and 7 be dissipative type FSS substrate；
Fig. 3 is FSS unit arrangement mode of the present invention；
Fig. 4 is the X-band microwave absorbing property of the embodiment of the present invention；
Fig. 5 is the HF/VHF pass-band performance of the embodiment of the present invention.
Specific embodiment
Below with reference to specific example and attached drawing, the present invention is described in detail.
By taking certain ship mast antenna house wave transparent/stealth technology index as an example, technical indicator are as follows: working frequency range: HF/VHF, work
Make bandwidth: 500MHz；Wave transmission rate: >=90% (in bandwidth of operation), stealthy frequency range: X-band, reflectivity: >=-20dB.Due to day
Irdome shape be non-low RCS shape (oval outer shape), therefore select dissipative type FSS radome research and development proposal as shown in Fig. 2, by
Antenna house cover 4, dissipative type FSS substrate 5, dissipative type FSS film 6, dissipative type FSS substrate 7.
The FSS cellular construction of FSS film 6 is as shown in Figure 1,3, is the square of fractal structure, the well word structure including center
Expand squarely in the end of patch 1 and big square patch 2 positioned at square quadrangle, four arms of well word structure patch 1
Prong like 11 arranges small square patch 3 in rectangular prong like internal symmetry, the height H of rectangular prong like 11 and big
2 side length a of square patch is consistent, and the side of the square of the outer side edges and fractal structure of small square patch 3 is overlapped, well word structure
Gap, big square patch 2 between 1 arm of patch and the gap b between rectangular prong like 11 and small square patch 3 with
Gap between rectangular prong like 11 is wide.
FSS cellular construction preferred proportion is as follows: side length a=4b~6b of big square patch 2, small 3 side of square patch
Long c=2b~3b, four wide d=0.8b~1.2b of arm of well word structure patch 1；FSS cellular construction side length L=10b~
The carbon film thickness of 20b, FSS cellular construction is 0.01mm~0.02mm.
Optimization design:
Establish dissipative type FSS structural model in professional electromagnetic simulation software, including radome cover, FSS cellular construction,
Substrate.The electrical parameter (such as dielectric constant, loss tangent) of each layer medium is accurately inputted in the model of foundation.Antenna house material
Material are as follows: cover material is Quartz ceramic material；Base material is quartz fibre/cyanate composite material.
It can be obtained by optimization analysis, FSS cellular construction is with a thickness of 0.018mm, cover thickness 3.0mm, substrate thickness
0.5mm.B=0.2mm, a=1.05mm, c=0.35mm, d=0.18mm, L=3.61mm
Processing technology:
Conductive carbon black is evenly applied on processing release paper with doctor knife coater, carbon film is made, thickness is applied by control
Degree realizes the control to carbon film sheet resistance.By prepare meet sheet resistance requirement carbon film plate using laser cutting machine by
The good shape of design optimization is cut into FSS unit, and each FSS unit is arranged in medium substrate by design parameter.
The ship mast antenna house HF/VHF pass-band performance and X-band microwave absorbing property being prepared according to above-mentioned parameter are as schemed
4, shown in 5, it can be seen that technical indicator can be fully met: working frequency range HF/VHF, bandwidth of operation 500MHz；Wave transmission rate >=
90% (in bandwidth of operation), stealthy frequency range X-band, reflectivity >=-20dB.
Unspecified part of the present invention is known to the skilled person technology.
Claims (10)
1. a kind of dissipative type wide-band and wave-absorbing FSS structure, it is characterised in that: molding on dielectric-slab using carbon film spraying process
Patch-type FSS cellular construction, the FSS cellular construction is the square of fractal structure, using square grid periodic arrangement；
The square of the fractal structure includes the well word structure patch (1) at center and the big square positioned at square quadrangle
Squarely prong like (11) are expanded in the end of patch (2), four arms of the well word structure patch (1), in rectangular fork
Shape inside configuration is arranged symmetrically small square patch (3), the height H of rectangular prong like (11) and big square patch (2) side
Long a is consistent, and the side of the square of the outer side edges and fractal structure of small square patch (3) is overlapped, well word structure patch (1) arm
Between gap, the gap b between big square patch (2) and rectangular prong like (11) and small square patch (3) and side
Gap between shape prong like (11) is wide.
2. a kind of dissipative type wide-band and wave-absorbing FSS structure according to claim 1, it is characterised in that: the big pros
Shape patch (2) side length a=4b~6b, described small square patch (3) side length c=2b~3b, the well word structure patch
(1) four wide d=0.8b~1.2b of arm.
3. a kind of dissipative type wide-band and wave-absorbing FSS structure according to claim 1, it is characterised in that: the FSS unit
Structure side length L=10b~20b.
4. a kind of dissipative type wide-band and wave-absorbing FSS structure according to claim 1, it is characterised in that: the gap b's
Value range is 0.1mm~0.5mm.
5. a kind of dissipative type wide-band and wave-absorbing FSS structure according to claim 1, it is characterised in that: the FSS unit
The carbon film thickness of structure is 0.01mm~0.02mm.
6. a kind of dissipative type wide-band and wave-absorbing FSS structure according to claim 1, it is characterised in that: the square
Gap b between gap between grid and big square patch (2) and rectangular prong like (11) is wide.
7. a kind of dissipative type wide-band and wave-absorbing FSS structure preparation method, which is characterized in that realized by following steps:
Conductive carbon black is evenly applied on processing release paper with doctor knife coater, carbon film plate is made by the first step；
FSS cellular construction is arranged in medium by second step, shape needed for the carbon film plate prepared is cut into FSS cellular construction
In substrate, the FSS cellular construction is the square of fractal structure, well word structure patch (1) including center and is located at just
The end expansion squarely of the big square patch (2) of rectangular quadrangle, four arms of the well word structure patch (1) is forked
Structure (11) arranges small square patch (3) in rectangular prong like internal symmetry, the height H of rectangular prong like (11) with
Big square patch (2) side length a is consistent, and the side of the square of the outer side edges and fractal structure of small square patch (3) is overlapped, well
Gap, big square patch (2) between word structure patch (1) arm and the gap b between rectangular prong like (11) and small
Gap between square patch (3) and rectangular prong like (11) is wide.
8. a kind of dissipative type wide-band and wave-absorbing FSS structure preparation method according to claim 7, it is characterised in that: described
Big square patch (2) side length a=4b~6b in second step, small square patch (3) side length c=2b~3b, well word structure patch
Four wide d=0.8b~1.2b of arm of piece (1).
9. a kind of dissipative type wide-band and wave-absorbing FSS structure preparation method according to claim 7, it is characterised in that: described
The value range of FSS cellular construction side length L=10b~20b in second step, gap b are 0.1mm~0.5mm.
10. a kind of dissipative type wide-band and wave-absorbing FSS structure preparation method according to claim 7, it is characterised in that: described
Carbon film thickness is 0.01mm~0.02mm in the first step.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| SE2100152A1 (en) * | 2021-10-18 | 2023-04-19 | Saab Ab | A product and method for frequency selective camouflage material |
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|---|---|---|---|---|
| CN111180839B (en) * | 2018-11-13 | 2021-11-30 | 航天特种材料及工艺技术研究所 | Broadband electromagnetic wave absorption structure based on frequency selective surface |
| CN112117550B (en) * | 2019-06-21 | 2023-11-03 | 深圳市环波科技有限责任公司 | Wave absorbing unit structure |
| CN110429389B (en) * | 2019-08-08 | 2021-01-05 | 中国科学院长春光学精密机械与物理研究所 | Wave-absorbing structure |
| CN112072320A (en) * | 2020-09-04 | 2020-12-11 | 武汉灵动时代智能技术股份有限公司 | Quasi-lumped FSS structure based on geometric separable inductor and capacitor |
| CN114614266B (en) * | 2022-05-11 | 2022-08-12 | 成都飞机工业（集团）有限责任公司 | X-band-pass absorption and penetration integrated frequency selective surface structure |
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| WO2023068984A1 (en) * | 2021-10-18 | 2023-04-27 | Saab Ab | A product and method for frequency selective camouflage material |
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