CN107968265B - High-performance wave absorber design method based on scaling theory - Google Patents

High-performance wave absorber design method based on scaling theory Download PDF

Info

Publication number
CN107968265B
CN107968265B CN201711279118.2A CN201711279118A CN107968265B CN 107968265 B CN107968265 B CN 107968265B CN 201711279118 A CN201711279118 A CN 201711279118A CN 107968265 B CN107968265 B CN 107968265B
Authority
CN
China
Prior art keywords
wave
absorbing material
scaling
absorbing
layer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201711279118.2A
Other languages
Chinese (zh)
Other versions
CN107968265A (en
Inventor
许勇刚
袁黎明
王晓冰
梁子长
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Radio Equipment Research Institute
Original Assignee
Shanghai Radio Equipment Research Institute
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Radio Equipment Research Institute filed Critical Shanghai Radio Equipment Research Institute
Priority to CN201711279118.2A priority Critical patent/CN107968265B/en
Publication of CN107968265A publication Critical patent/CN107968265A/en
Application granted granted Critical
Publication of CN107968265B publication Critical patent/CN107968265B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]

Abstract

The invention discloses a high-performance wave absorber design method based on a scaling theory, which comprises the following steps: s1, obtaining corresponding electromagnetic parameters and prototype frequency based on the prototype wave-absorbing material, wherein the electromagnetic parameters comprise dielectric constant and magnetic conductivity; s2, analyzing the impedance characteristics and the change rule function of each layer of material according to the reflectivity calculation theory of the multilayer material and by combining the electromagnetic parameters of the prototype wave-absorbing material and the prototype frequency to obtain an impedance characteristic function; constructing a scaling material with the same shape as the prototype wave-absorbing material by using a scaling theory, and theoretically designing the scaling electromagnetic parameters and the thickness of each layer of material according to impedance characteristic parameters; s3, determining a scaling frequency coefficient and a shape scaling factor to obtain a material formula meeting the impedance characteristic; and S4, constructing the required high-performance wave absorber by using the material formula. The advantages are that: the fast design of the broadband wave-absorbing material can be realized.

Description

High-performance wave absorber design method based on scaling theory
Technical Field
The invention relates to the technical field of wave absorber design, in particular to a high-performance wave absorber design method based on a scaling theory.
Background
The design of the high-performance wave absorber is an important step for realizing the wave absorber, and is a basis for preparing the high-performance wave absorber subsequently. At present, high-performance wave absorbers are mainly characterized by being thin, light, wide and strong, and the most widely applied wave absorbers mainly comprise two characteristics of light weight and strong absorption. The structural wave-absorbing material is the most common high-performance wave-absorbing body, is mainly manufactured by compression molding or cutting, has the characteristics of bearing and realizing the functions of components, utilizes a self-adaptive geometric structure to achieve the impedance matching characteristic in the design, generally needs to consider the material selection problems in two aspects of structure and material, simultaneously needs to have a specific shape, and has a long development period.
At present, the design of a high-performance wave absorber mainly takes a multilayer material theory as a main part, for example, patent CN105196638A proposes a broadband wave-absorbing force-bearing composite material and a preparation method thereof, the material comprises a wave-transmitting foam layer, a wave-transmitting skin, an electrical loss wave-absorbing layer and a shielding bottom layer in design, and a typical multilayer structure is designed through the optimized design of multilayer materials.
Patent CN104979641A proposes a broadband wave absorber and its application, where the wave absorber is overall a sandwich structure, and there are particle composite loss layers on both sides and a high dielectric thin layer in the middle, and the design theory is still the multilayer material design theory.
Patent CN104893606A proposes a broadband wave-absorbing film, which comprises an insulating layer, a wave-absorbing layer as a reflective layer, and wave-absorbing and release material layers. A first adhesive layer is arranged between the insulating layer and the wave absorbing layer, a second adhesive layer is arranged between the wave absorbing layer and the wave absorbing layer, and the preparation method is simple pasting.
Patent CN104893606A proposes a broadband wave-absorbing film, which includes an insulating layer, a wave-absorbing layer as a reflective layer, and wave-absorbing and release material layers; a first adhesive layer is arranged between the insulating layer and the wave-absorbing layer; a second adhesive layer is arranged between the wave absorbing layer and the wave absorbing layer; the third adhesive layer is arranged between the wave-absorbing material layer and the release material layer, the broadband wave-absorbing adhesive film has strong electromagnetic wave absorption property, the attenuation rate of 2-10 GHz electromagnetic waves reaches 85%, however, the corresponding wave-absorbing performance is difficult to achieve within 10-18 GHz of a slightly high frequency band, the broadband absorption still faces to be insufficient, and the internal structure of the wave-absorbing material is not considered yet.
Patent CN104485515A proposes a broadband wave-absorbing material loaded with lumped elements, which includes a substrate material and an annular metal wire disposed on the substrate material, wherein a cross-shaped metal wire is disposed in a ring of the annular metal wire, and the annular metal wire is a circular ring, a square ring or a hexagonal ring; the upper end, the lower end, the left end and the right end of the cross-shaped metal wire are respectively connected with a resistor/a capacitor in series, and the positions on the annular metal wire, which correspond to the upper end, the lower end, the left end and the right end of the cross-shaped metal wire, are also connected with a resistor/a capacitor in series. The invention has 90-degree rotational symmetry in structure, can well overcome the polarization sensitivity of electromagnetic waves, and has high absorptivity to the electromagnetic waves in a wide frequency band.
Patent CN104030668A proposes a multi-resonance absorption zirconium-doped barium ferrite broadband wave-absorbing material, which adopts barium zinc or barium zirconium ferrite as an absorbent and a mixture of two powders, and combines the materials with different intrinsic parameter peak values into a composite system, each intrinsic parameter in the formed wave-absorbing system has correspondingly different characteristic resonance frequencies, and the resonance frequency appearance range of the composite material is larger than the resonance frequency appearance range of the composite single-phase material itself.
Patent CN103774328A proposes a method for processing a suede fabric capable of absorbing broadband electromagnetic waves, which selects conductive fiber blended yarns to weave, or selects conductive fiber blended yarns to weave double-layer fabrics. The wave absorbing adhesive with good adhesive property is prepared by diluting and mixing the wave absorbing agent and the flexible adhesive uniformly. The frequency range of the broadband electromagnetic wave absorption fabric with the suede structure for absorbing the electromagnetic waves is about 300 MHz-40 GHz, the material has a good shielding effect, but the wave absorption performance is very limited, and the wave absorption frequency band is still narrow.
Patent CN103347379A proposes a flame-retardant broad-band high-power composite wave-absorbing material and a preparation method thereof, wherein the material comprises a shell, an inner core and a base, the shell is a polyhedron formed by a group of pyramids in parallel, and the wedges of the pyramids face to the same side; the inner core is positioned in the shell, and the base is positioned at the bottom of the shell; the shell is made of non-woven fabrics, and the inner core and the base are made of polyurethane foam; the inner core and the base are dipped by a second flame-retardant wave-absorbing agent; the wave-absorbing material has excellent wave-absorbing performance and flame retardant performance, the preparation method is simple and easy to implement, the influence of the surface structure appearance on the wave-absorbing frequency band widening is considered, and the internal structure is not involved.
In conclusion, the design of the broadband high-performance wave absorber mainly focuses on the multilayer design and the simple single-layer wave absorbing material design, and the design principle has a great space for improvement. With the increase of the demand of people on high-performance wave absorbers, civil wave absorbing materials have appeared in series of products, such as mobile phone radiation-proof patches, wave absorbing pyramids and the like, but due to the limitation of manufacturing technology, the product structure is single, and the designability is poor. Therefore, the efficient design of the high-performance wave absorber is urgently required, the designability of the wave absorbing material can be widened, and the preparation means of the wave absorbing material can be enriched.
Disclosure of Invention
The invention aims to provide a high-performance wave absorber design method based on a scaling theory, which can realize the rapid design of a broadband wave absorbing material, simplify the design process by utilizing the existing high-performance wave absorber and the corresponding structure thereof, realize the efficient design of a similar structure, ensure the corresponding wave absorbing performance, be applied to the electromagnetic protection of civil or military equipment, low-scattering targets, buildings and the like, realize the absorption of electromagnetic waves and reduce the electromagnetic scattering of the targets.
In order to achieve the purpose, the invention is realized by the following technical scheme:
a high-performance wave absorber design method based on a scaling theory is characterized by comprising the following steps:
s1, selecting a high-performance wave absorbing body with a prototype wave band, and obtaining corresponding electromagnetic parameters and prototype frequency based on a corresponding prototype wave absorbing material, wherein the electromagnetic parameters comprise dielectric constant and magnetic permeability;
s2, analyzing the impedance characteristics and the change rule function of each layer of wave-absorbing material according to the reflectivity calculation theory of the multi-layer material and by combining the electromagnetic parameters of the prototype wave-absorbing material and the prototype frequency to obtain an impedance characteristic function;
constructing a scaling material with the same shape as the original wave-absorbing material by using a scaling theory, and theoretically designing the scaling electromagnetic parameters and the thickness of each layer of wave-absorbing material according to impedance characteristic parameters;
s3, determining a scaling frequency coefficient and a shape scaling factor to obtain a material formula meeting the impedance characteristic;
and S4, constructing the required high-performance wave absorber by using the material formula.
The method for designing the high-performance wave absorber based on the scaling theory comprises the following steps:
the prototype wave-absorbing material is a dielectric wave-absorbing material or a magnetic wave-absorbing material, and the wave-absorbing particles are carbon series absorbents or iron series absorbents;
the wave absorbing structure of the high-performance wave absorber with the prototype wave band is a cubic cone structure, the wave absorber comprises two layers, namely an upper part cone and a lower part column, the height of the upper part cone is H1, the bottom surface width L of the upper part cone, the angle theta of the upper part cone is 2 arctan (0.5L/H1), and the height of the lower part column is H2;
the internal wave-absorbing particles are uniformly distributed, and the electromagnetic parameters integrally corresponding to the prototype wave-absorbing material comprise dielectric constantph＝′ph-j″phAnd magnetic permeability muph＝μ′ph-jμ″phCorresponding to a prototype frequency of fph，phIs a complex dielectric constant'phIs the real part of dielectric constantphIs the imaginary part of the dielectric constant, muphIs complex permeability,. mu'phIs the real part of magnetic permeability, μ ″)phIs the imaginary part of the permeability.
In the method for designing a high-performance absorber based on the scaling theory, in step S2:
the scaling material is dielectric wave-absorbing material or magnetic loss material.
In the method for designing a high-performance absorber based on the scaling theory, step S2 specifically includes:
s21, calculating equivalent electromagnetic parameters of each layer of wave-absorbing material of the prototype wave-absorbing material according to the reflectivity calculation theory of the multiple layers of materials:
high-performance wave absorber prototype wave-absorbing material with prototype wave band of cubic cone structure is equivalent to n layers of wave-absorbing materials which are all parallel to the bottom surface of the material, the structural form of each layer of wave-absorbing material is a conical table structure, the distribution of each layer of wave-absorbing material is non-uniform, and the width of the top layer is diWidth of the bottom layer is di+1The height of each layer is H1/n, the transmission reflection coefficient corresponding to each layer of material is obtained through CST simulation, and the equivalent electromagnetic parameter corresponding to each layer of material is calculated according to the NRW methodnAnd mun，nAnd munThe dielectric constant and the magnetic permeability of the nth layer material are respectively set;
s22, calculating the scaling electromagnetic parameters of each layer of the wave-absorbing material of the prototype wave-absorbing material according to the calculation formula of the multilayer reflectivity:
in order to ensure that the reflectivity is unchanged, the surface impedance and the characteristic impedance of each layer of wave-absorbing material are ensured to be unchanged, namely:
Figure GDA0002664687220000041
and
Figure GDA0002664687220000042
before and after scaling, the ratio is kept unchanged;
in the formula, ZnIs the characteristic impedance of the n-th layer material, gammanIs the propagation constant of the n-th layer material, dnThe thickness of the nth layer material, C is the light speed, and v is the volume addition ratio of the wave-absorbing particles;
selecting a scaling coefficient as s and a scaling frequency as sf;
if the reduced thickness is dnS, obtaining
Figure GDA0002664687220000043
And
Figure GDA0002664687220000044
kept constant, by transformation, i.e. before and after the required scalingnAndnkeeping the structure unchanged, and designing the electromagnetic parameters of the wave absorption structure by the corresponding material;
if the thickness ratio s' after the reduction ratio is kept is different from the reduction ratio coefficient s, and the reduction ratio thickness is dnS' at which time maintenance is required
Figure GDA0002664687220000045
And
Figure GDA0002664687220000046
meanwhile, the method is established and simplified as follows:
Figure GDA0002664687220000047
by means of the change in the direction of the axis,s n＝ns′/s，μs n＝μns'/s, to obtain a condensationDielectric constant sn and magnetic permeability mu corresponding to specific frequencys n；
S23, constructing a scaling material with the same shape as the original wave-absorbing material by using a scaling theory, and theoretically designing the scaling electromagnetic parameters and the thickness of each layer of wave-absorbing material according to the impedance characteristic parameters.
In the method for designing a high-performance absorber based on the scaling theory, in step S21:
during CST simulation, 3 sections are selected for simulation to obtain equivalent electromagnetic parameters of each section, then equivalent electromagnetic parameters of other sections are obtained by adopting a parabolic interpolation method, the 3 sections are respectively the 1 st section, the INT (n/2) th section and the nth section, wherein the INT is an integer function.
In the method for designing a high-performance absorber based on the scaling theory, in step S23:
for the scaling design of the dielectric wave-absorbing material, s' is selected to ensure thats n＝n(ii) a When the principle that the shape of a scaled structure is the same is adopted, the scaled material of the non-uniform structure obtained by inversion of the equivalent structure is consistent with the dielectric constant of the original wave-absorbing material, meanwhile, when the dielectric constant changes smaller along with the increase of frequency, the structure does not need to be adjusted at the moment, only the equivalent structure design is needed, when the dielectric constant of the original wave-absorbing material has certain change, for the dielectric wave-absorbing material, only the volume addition ratio of wave-absorbing particles needs to be adjusted at the moment, and the volume addition ratio and the wave-absorbing particle type corresponding to each layer of wave-absorbing material are obtained through inversion.
In the method for designing a high-performance absorber based on the scaling theory, in step S23:
for the scaling design of the magnetic wave-absorbing material, when s' and s are different, the requirement is satisfieds n＝ns′/s，μs n＝μns′/s。
In the method for designing a high-performance absorber based on the scaling theory, in step S23:
for the filling type magnetic wave-absorbing material, interpolation fitting is carried out on the dielectric constant according to electromagnetic material electromagnetic parameter libraries with different volume ratios to obtain the dielectric constant of the uniformly distributed material, the equivalent medium theory is utilized to further obtain the preparation ratio of the corresponding wave-absorbing material, the corresponding wave-absorbing material is prepared according to the preparation ratio, and the relative error of the selected parameters in the design is within 10 percent.
In the method for designing a high performance absorber based on the scaling theory, step S23 further includes:
calculating the dielectric constant of the wave-absorbing material prepared according to the preparation proportion, and performing parameter fitting by adopting a third phase absorbent when the dielectric constant value has deviation from a target dielectric constant value;
and aiming at the third phase absorbent, calculating the electromagnetic parameters of the wave-absorbing material as follows:
Figure GDA0002664687220000061
in the formula, q is the volume addition ratio of the wave-absorbing particles,
Figure GDA0002664687220000062
is the dielectric loss tangent, tan, of the mixturemsTan, the dielectric loss tangent of the wave-absorbing particlesmtThe required electromagnetic parameters are obtained by introducing the third phase absorbent to adjust the dielectric constant of the material for the dielectric loss tangent value containing the third phase absorbent, and the third phase absorbent is dielectric wave-absorbing particles.
Compared with the prior art, the invention has the following advantages:
1. the broadband wave-absorbing material can be quickly designed, the existing high-performance wave-absorbing body and the corresponding structure thereof are utilized, the design process is simplified, the high-efficiency design of the similar structure is realized, the corresponding wave-absorbing performance is ensured, and the broadband wave-absorbing material can be applied to the electromagnetic protection of civil or military equipment, low-scattering targets, buildings and the like, the absorption of electromagnetic waves is realized, and the electromagnetic scattering of the targets is reduced;
2. the design method can also be used for designing other materials with complex structures, and is an efficient design method of complex wave-absorbing materials with application prospects.
Drawings
FIG. 1 is a flow chart of a method of the present invention;
FIG. 2 is a schematic structural diagram of a prototype wave-absorbing material in the present invention;
FIG. 3 is an equivalent structure diagram of the i-th layer of the wave-absorbing material in the present invention;
FIG. 4 is a reflectivity curve of a high performance absorber before and after the optimal design in the present invention;
FIG. 5 shows the equivalent electromagnetic parameters of the third layer of the wave-absorbing structure of the prototype wave-absorbing material in the embodiment of the invention;
FIG. 6 is a diagram illustrating equivalent dielectric constants and permeability values required to be obtained by each layer scaling design in an embodiment of the present invention;
FIG. 7 shows equivalent parameters and addition ratios of wave-absorbing materials of respective layers in the embodiment of the invention.
Detailed Description
The present invention will now be further described by way of the following detailed description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings.
As shown in fig. 1, the invention discloses a method for designing a high-performance wave absorber based on a scaling theory, which comprises the following steps:
s1, selecting a high-performance wave absorbing body with a prototype wave band, and obtaining corresponding electromagnetic parameters and prototype frequency based on a corresponding prototype wave absorbing material, wherein the electromagnetic parameters comprise dielectric constant and magnetic permeability;
s2, analyzing the impedance characteristics and the change rule function of each layer of wave-absorbing material according to the reflectivity calculation theory of the multi-layer material and by combining the electromagnetic parameters of the prototype wave-absorbing material and the prototype frequency to obtain an impedance characteristic function;
constructing a scaling material with the same shape as the original wave-absorbing material by using a scaling theory, and theoretically designing the scaling electromagnetic parameters and the thickness of each layer of wave-absorbing material according to impedance characteristic parameters;
s3, determining a scaling frequency coefficient and a shape scaling factor to obtain a material formula meeting the impedance characteristic;
selecting a scaling coefficient as s and a scaling frequency as sf;
if the reduced thickness is dnS, by conversion, i.e. before and after the required scalingnAndnkeeping the structure unchanged, and designing the electromagnetic parameters of the wave absorption structure by the corresponding material;
if the thickness ratio s' after the reduction ratio is kept is different from the reduction ratio coefficient s, and the reduction ratio thickness is dnThe corresponding dielectric constant sn and magnetic permeability mu under the scaling frequency are obtained through conversionnComprises the following steps:s n＝ns′/s，μs n＝μns′/s。
the preparation of the material adopts an equivalent medium theory based on an electromagnetic parameter library, the formula close to the set parameters is calculated in an optimized mode, and when the deviation is large, a third preparation particle is added.
And S4, constructing the required high-performance wave absorber by using the material formula.
The prototype wave-absorbing material is a dielectric wave-absorbing material or a magnetic wave-absorbing material, the wave-absorbing particles are carbon series absorbents or iron series absorbents, and the carbon series absorbents comprise carbon black, carbon nano tubes, carbon fibers, graphite, graphene and the like; the iron absorbent includes ferrite, carbonyl iron, iron-silicon-aluminum, etc.; the prototype wave-absorbing material is a cubic cone structure, taking a single structural unit of the material as an example, as shown in fig. 2, the wave-absorbing structure of the high-performance wave absorber in the prototype wave band is a cubic cone structure, the wave absorber comprises two layers, an upper part cone and a lower part cylinder, the height of the upper part cone is H1, the bottom surface width L of the upper part cone, the angle theta of the upper part cone is 2 arctan (0.5L/H1), the height of the lower part cylinder is H2, and the corresponding electromagnetic parameters comprise dielectric constantph＝′ph-j″phAnd magnetic permeability muph＝μ′ph-jμ″phCorresponding to a prototype frequency of fph，phIs a complex dielectric constant,phIs the real part of the dielectric constant,phIs the imaginary part of the dielectric constant, muphIs complex permeability, muphIs the real part of the magnetic permeability, muphIs the imaginary part of the permeability.
According to the reflectivity calculation theory of the multilayer materials, the prototype wave-absorbing material with the cubic cone structure is equivalent to the multilayer wave-absorbing material, the multilayer materials are all parallel to the bottom surface of the material, and the impedance calculation formula of the multilayer materials is as follows:
Figure GDA0002664687220000081
Zin1＝Z1tanh(γ1d1)
wherein Z isinnRepresents the surface resistance of the n-th layer,
Figure GDA0002664687220000082
is the characteristic impedance of the nth layer material,nand munIs the permittivity and permeability of the nth layer material,
Figure GDA0002664687220000083
is the propagation constant of the n-th layer material, dnIs the thickness of the nth layer material and C is the speed of light.
The step S2 specifically includes:
s21, calculating equivalent electromagnetic parameters of each layer of wave-absorbing material of the prototype wave-absorbing material according to the reflectivity calculation theory of the multiple layers of materials:
in this embodiment, since the structural form of each layer of material is a tapered mesa structure (which may be other structures), for a periodic structure, the material distribution is non-uniform, as shown in fig. 3, which is not suitable for the theoretical calculation of a multilayer uniform material, and an equivalent design is required.
The wave absorbing structure of the prototype wave absorbing material body with the cubic cone structure is equivalent to n layers of wave absorbing materials, the n layers of wave absorbing materials are all parallel to the bottom surface of the material, the structural form of each layer of wave absorbing material is a conical table structure (the conical structure at the topmost layer can be regarded as a conical table structure with the width of the top layer being 0), the distribution of each layer of wave absorbing material is non-uniform, taking the square table structure as an example in the figure and the width of the top layer being diWidth of the bottom layer is di+1The height of each layer is H1/n, and a transmission reflection system corresponding to each layer of material is obtained through CST simulationCounting, further calculating equivalent electromagnetic parameters corresponding to each layer of material according to NRW methodnAnd mun，nAnd munThe dielectric constant and the magnetic permeability of the nth layer material are respectively set; preferably, 3 sections are selected for simulation during CST simulation to obtain equivalent electromagnetic parameters of each section, then equivalent electromagnetic parameters of other sections are obtained by adopting a parabolic interpolation method, the 3 sections are respectively the 1 st section, the INT (n/2) th section and the nth section, wherein the INT is an integer function;
s22, calculating the scaling electromagnetic parameters of each layer of the wave-absorbing material of the prototype wave-absorbing material according to the calculation formula of the multilayer reflectivity:
in order to ensure that the reflectivity is unchanged, the surface impedance and the characteristic impedance of each layer of wave-absorbing material are ensured to be unchanged, namely:
Figure GDA0002664687220000084
and
Figure GDA0002664687220000085
before and after scaling, the ratio is kept unchanged;
in the formula, ZnIs the characteristic impedance of the n-th layer material, gammanIs the propagation constant of the n-th layer material, dnThe thickness of the nth layer material, C the light speed and f the volume addition ratio of the wave-absorbing particles;
selecting a scaling coefficient as s and a scaling frequency as sf;
if the reduced thickness is dnS, obtaining
Figure GDA0002664687220000091
And
Figure GDA0002664687220000092
kept constant, by transformation, i.e. before and after the required scalingnAndnkeeping the structure unchanged, and designing the electromagnetic parameters of the wave absorption structure by the corresponding material;
if the thickness ratio s' after the reduction ratio is kept is different from the reduction ratio coefficient s, and the reduction ratio thickness is dnS' at which time maintenance is required
Figure GDA0002664687220000093
And
Figure GDA0002664687220000094
meanwhile, the method is established and simplified as follows:
Figure GDA0002664687220000095
by means of the change in the direction of the axis,s n＝ns′/s，μs n＝μns'/s to obtain the corresponding dielectric constant sn and magnetic permeability mu under the scaling frequencys n；
Therefore, after the high-performance wave-absorbing material of the prototype frequency band is determined, the corresponding dielectric constant and magnetic permeability under the scaled frequency can be obtained according to the relational expression by determining the frequency scaling coefficient and the size scaling coefficient.
S23, constructing a scaling material with the same shape as the original wave-absorbing material by using a scaling theory, and theoretically designing the scaling electromagnetic parameters and the thickness of each layer of wave-absorbing material according to the impedance characteristic parameters.
In the step S23:
for the scaled design of dielectric type wave-absorbing material, only the dielectric constant is usually includednAt this time μ n1. When s' and s are different, μ will appears nThis class of materials is difficult to achieve for the formulation of conventional materials, i.e. the real part of the permeability is s'/s and the imaginary part is 0. Therefore, for the dielectric absorbing material, s' is preferably selected to ensure thats n＝n(ii) a When the principle that the shape of the scaled structure is the same is adopted, the scaled material of the non-uniform structure obtained by inversion of the equivalent structure is consistent with the dielectric constant of the original wave-absorbing material, meanwhile, when the dielectric constant changes less along with the increase of the frequency, the structure does not need to be adjusted at the moment, only the equivalent structure design is needed, and when the dielectric constant of the original wave-absorbing material has certain change, for the dielectric wave-absorbing material, the scaled material has the same dielectric constant as the original wave-absorbing materialThe volume addition ratio of the wave-absorbing particles is only required to be adjusted, the volume addition ratio and the wave-absorbing particle type corresponding to each layer of wave-absorbing material are obtained through inversion, and the specific process of adjusting the volume addition ratio of the wave-absorbing particles is as follows:
for the filled wave-absorbing material with square frustum structural distribution, firstly, the equivalent dielectric constant of the material in the non-uniform structural area needs to be inverted, the adopted method is an equivalent medium theory, and the expression is as follows:
Figure GDA0002664687220000101
wherein p is the volume addition ratio of the region structure, andiandmthe dielectric constants of the additive material and air, respectively, and, in general,m＝1。
when the principle that the shape of the scaled structure is the same is adopted, the dielectric constants of the scaled material of the non-uniform structure obtained by inversion of the equivalent structure and the prototype wave-absorbing material are consistent. Meanwhile, when the dielectric constant change is generally small along with the increase of the frequency, the structure does not need to be adjusted at the moment, and only the design of an equivalent structure is needed. When the dielectric constant of the prototype wave-absorbing material has a certain change, the dielectric wave-absorbing material only needs to adjust the addition ratio of particles, the method adopted for adjustment is still the equivalent medium theory, and only the method in the formula needs to be combinediAndmrespectively changing the dielectric constant of the material and the dielectric constant of the matrix at corresponding concentrations,mand (2) obtaining the corresponding addition ratio and wave-absorbing particle type of each layer of wave-absorbing material through inversion.
For the scale design of the magnetic wave-absorbing material, the parameters comprise dielectric constantnAnd munAt this time μnNot equal to 1, for magnetic absorber materials there is usually some variation in permeability with increasing frequency. When s' and s are different, it is necessary to satisfys n＝ns′/s，μs n＝μns'/s. This condition is also possible for magnetic materials. Calculation method and dielectric constant interpolation fitting process ITherefore, because the dielectric constant of the magnetic material is easy to adjust and the magnetic permeability is difficult to adjust, the magnetic permeability is firstly interpolated, and the magnetic permeability of the material with the distributed structure is inverted based on the addition ratio of each layer of wave-absorbing material. The adopted method is still equivalent medium theory and has isotropic magnetic permeability mueffThe following equation is satisfied:
Figure GDA0002664687220000102
wherein p is the region-to-volume ratio of the particles, n is the shape factor, and μiAnd mumPermeability of the added particles and air, respectively, in general, mum＝1。
For the filling type magnetic wave-absorbing material, performing interpolation fitting on the dielectric constant according to electromagnetic material electromagnetic parameter libraries with different volume ratios to obtain the dielectric constant of the uniformly distributed material, further obtaining the preparation proportion of the corresponding wave-absorbing material by using an equivalent medium theory, configuring the corresponding wave-absorbing material, and selecting the parameters with the relative error within 10% in the design;
meanwhile, the dielectric constant of the wave-absorbing material prepared according to the preparation proportion is calculated, and when the dielectric constant value has deviation from the target dielectric constant value, a third phase absorbent is adopted for parameter fitting;
and aiming at the third phase absorbent, calculating the electromagnetic parameters of the wave-absorbing material as follows:
Figure GDA0002664687220000103
in the formula, q is the volume addition ratio of the wave-absorbing particles,
Figure GDA0002664687220000111
is the dielectric loss tangent, tan, of the mixturemsTan, the dielectric loss tangent of the wave-absorbing particlesmtAdjusting the dielectric constant of the material by introducing the third phase absorbent to obtain the desired dielectric loss tangent valueThe electromagnetic parameters are required, and the third phase absorbent is dielectric wave-absorbing particles comprising carbon materials, SiC, ZnO and the like.
In addition, the magnetic permeability and the formula of the uniformly distributed material can be obtained by fitting the magnetic permeability according to the electromagnetic material electromagnetic parameter libraries with different volume ratios, for the convenience of design, when the material filling proportion deviation corresponding to the scaling design is not large, the average addition ratio of the three can be selected to design the wave absorber, and the wave absorber with excellent performance can be obtained although the design result has certain error.
Example one
The embodiment is designed by iso-electromagnetic parameters
Prototype wave band high performance absorber:
firstly, selecting a high-performance wave absorbing body with a prototype wave band, wherein the wave absorbing structure is a cubic cone structure, the corresponding prototype wave absorbing material is a dielectric wave absorbing material, the wave absorbing particles are carbon black, and the volume addition ratio is 5%. The prototype wave-absorbing material mainly comprises two layers. Taking a single structural unit of material as an example, the structural dimensions mainly include an upper end height H1-400 mm, a lower end height H2-40 mm, a total height 440mm, and a width L-180 mm. The internal materials of the prototype wave-absorbing material are uniformly distributed, and the corresponding electromagnetic parameters comprise dielectric constantph11-j5.5 and permeability μ 1, corresponding to a prototype frequency of 5 GHz.
And (3) impedance analysis of the prototype frequency band wave absorber structure:
according to the calculation formula of the multilayer reflectivity, in order to ensure that the reflectivity is unchanged, the surface impedance and the characteristic impedance of each layer need to be ensured to be unchanged, namely:
Figure GDA0002664687220000112
and
Figure GDA0002664687220000113
before and after scaling, the ratio is kept unchanged. If the scaling coefficient is s and the scaling frequency is sf, the method can be used for solving the problem of low noise. If the reduced thickness is dnS, and can further be obtained
Figure GDA0002664687220000114
And
Figure GDA0002664687220000115
remaining unchanged, i.e. mu before and after scalingnAndnand keeping the structure unchanged, wherein the corresponding material needs to design the structure according to the electromagnetic parameters.
The equivalent electromagnetic parameter design method comprises the following steps:
for the scaling design of the dielectric wave-absorbing material, s' is preferably selected to be 2, and only the requirement of ensuring that the dielectric wave-absorbing material is scaled down is neededs n＝n. With the increase of the frequency, the dielectric constant of the carbon black material at the addition ratio of 5% does not change greatly, and the material only needs to be kept unchanged. At the moment, the corresponding material is still carbon black, the filling proportion is still 5% by volume, and the wave-absorbing material performance and the prototype wave-absorbing material can have good consistency.
Example two
Prototype wave band high performance absorber:
firstly, selecting a high-performance wave absorbing body with a prototype wave band, wherein the wave absorbing structure is a cubic cone structure, the corresponding prototype wave absorbing material is a magnetic loss type wave absorbing material, the wave absorbing particles are carbonyl iron, and the volume addition ratio is 20%. The prototype wave-absorbing material mainly comprises two layers. Taking a single structural unit of material as an example, the structural dimensions mainly include an upper end height H1 of 200mm, a lower end height H2 of 20mm, a total height of 220mm, and a width L of 90mm, where the upper end angle θ is 2 × arctan (0.225) °. The internal materials of the prototype wave-absorbing material are uniformly distributed, and the corresponding electromagnetic parameters comprise dielectric constantph10.63-j0.47 and permeability μph2.28-j1.18, corresponding to a prototype frequency of 5GHz, a scaling factor of 2 is set by itself.
And (3) impedance analysis of the prototype frequency band wave absorber structure:
since the structural form of each layer of material is a conical table structure, the material distribution is non-uniform distribution for a periodic structure, and as shown in fig. 3, the equivalent electromagnetic parameters of the material are calculated by reverse calculation based on the simulation of CST software. Selecting the width of the ith layer as diWidth of the bottom layer is di+1The height of each layer was 20 mm. After CST simulation, the layers 1, 10 and 20 can be obtainedThe transmission reflection coefficient corresponding to the material, and further the equivalent electromagnetic parameters corresponding to the material are calculated according to the NRW method, mainly comprising the dielectric constantnThe calculation results are shown in fig. 5.
According to the calculation formula of the multilayer reflectivity, in order to ensure that the reflectivity is unchanged, the surface impedance and the characteristic impedance of each layer need to be ensured to be unchanged, namely:
Figure GDA0002664687220000121
and
Figure GDA0002664687220000122
before and after scaling, the ratio is kept unchanged. The thickness ratio s' after the scaling is selected to be 0.8, which is different from the scaling coefficient s, and the scaling thickness is dnS' at which time maintenance is required
Figure GDA0002664687220000123
And
Figure GDA0002664687220000124
meanwhile, the method is established and simplified as follows:
Figure GDA0002664687220000125
after the above formula is processed, can obtains n＝ns′/s，μs n＝μns′/s。
The equivalent electromagnetic parameter design method comprises the following steps:
for the scale design of the magnetic wave-absorbing material, the parameters comprise dielectric constantnAnd munAt this time μnNot equal to 1, for magnetic absorber materials there is usually some variation in permeability with increasing frequency. When s' and s are different, it is necessary to satisfys n＝ns′/s，μs n＝μns'/s, the electromagnetic parameters corresponding to the 3 selected cross-sections are shown in FIG. 6.
Since the permittivity of the magnetic material is easily adjusted and the permeability is difficult to adjust, the permeability is interpolated to design the addition ratio of the fine particles. The method adopted is still equivalent medium theory, and the isotropic magnetic permeability generally satisfies the following equation:
Figure GDA0002664687220000131
wherein p is the region-to-volume ratio of the particles, n is the shape factor, and μiAnd mumPermeability of the added particles and air, respectively, in general, mu m1. For the filled wave-absorbing material with square frustum structure distribution, the non-uniform distribution effect also needs to be considered, namely, the magnetic conductivity is inverted, the magnetic conductivity is continuously approached, and the adopted method is still the equivalent medium theory, so that the preparation proportion and the material of the corresponding wave-absorbing material are obtained. And calculating the dielectric constant according to the preparation ratio and the materials.
The magnetic permeability and the formula of the uniformly distributed material can be obtained by fitting the magnetic permeability according to the electromagnetic material electromagnetic parameter libraries with different volume ratios, the corresponding addition ratio and the corresponding electromagnetic parameter under 10GHz are respectively shown in FIG. 7, the designed material is still a sheet carbonyl iron material, for the convenience of design, the material filling ratio deviation corresponding to the scaling design is not large, the average addition ratio of the three is selected to design the wave absorber, the addition ratio is 15%, and the wave absorber with excellent performance can be obtained even though the design result has certain errors.
After the scaling design, the reflectivity curve of the corresponding wave absorber is shown in figure 4, and it can be seen that the reflectivity value of the prototype wave-absorbing material in the range of 4.5-5.5GHz is lower than-45 dB and has good wave-absorbing performance, while the reflectivity of the material after the scaling design is lower than-50 dB for the range of the scaling frequency band of 9-11GHz, which is caused by the middle formula of the wave-absorbing material being modified to a certain extent and the deviation of electromagnetic parameters, and shows better wave-absorbing performance, it can be seen that the wave-absorbing material designed by the scaling theory can reach the wave-absorbing performance designed by the original target, and the performance of the wave-absorbing material can meet the engineering requirements of the high-performance wave absorber.
While the present invention has been described in detail with reference to the preferred embodiments, it should be understood that the above description should not be taken as limiting the invention. Various modifications and alterations to this invention will become apparent to those skilled in the art upon reading the foregoing description. Accordingly, the scope of the invention should be determined from the following claims.

Claims (7)

1. A high-performance wave absorber design method based on a scaling theory is characterized by comprising the following steps:
s1, selecting a high-performance wave absorbing body with a prototype wave band, and obtaining corresponding electromagnetic parameters and prototype frequency based on a corresponding prototype wave absorbing material, wherein the electromagnetic parameters comprise dielectric constant and magnetic permeability;
s2, analyzing the impedance characteristics and the change rule function of each layer of wave-absorbing material according to the reflectivity calculation theory of the multi-layer material and by combining the electromagnetic parameters of the prototype wave-absorbing material and the prototype frequency to obtain impedance characteristic parameters;
constructing a scaling material with the same shape as the original wave-absorbing material by using a scaling theory, and theoretically designing the scaling electromagnetic parameters and the thickness of each layer of wave-absorbing material according to impedance characteristic parameters;
s3, determining a scaling frequency coefficient and a shape scaling factor to obtain a material formula meeting the impedance characteristic;
s4, constructing a required high-performance wave absorber by using a material formula;
the prototype wave-absorbing material is a dielectric wave-absorbing material or a magnetic wave-absorbing material, and the wave-absorbing particles are carbon series absorbents or iron series absorbents;
the wave absorbing structure of the high-performance wave absorber with the prototype wave band is a cubic cone structure, the wave absorber comprises two layers, namely an upper part cone and a lower part column, the height of the upper part cone is H1, the bottom surface width L of the upper part cone, the angle theta of the upper part cone is 2 arctan (0.5L/H1), and the height of the lower part column is H2;
the internal wave-absorbing particles are uniformly distributed, and the electromagnetic parameters integrally corresponding to the prototype wave-absorbing material comprise dielectric constantph＝′ph-j″phAnd magnetic permeability muph＝μ′ph-jμ″phCorresponding to a prototype frequency of fph，phIs a complex dielectric constant'phIs the real part of dielectric constantphIs the imaginary part of the dielectric constant, muphIs complex permeability,. mu'phIs the real part of magnetic permeability, μ ″)phIs the imaginary part of the permeability;
the step S2 specifically includes:
s21, calculating equivalent electromagnetic parameters of each layer of wave-absorbing material of the prototype wave-absorbing material according to the reflectivity calculation theory of the multiple layers of materials:
high-performance wave absorber prototype wave-absorbing material with prototype wave band of cubic cone structure is equivalent to n layers of wave-absorbing materials which are all parallel to the bottom surface of the material, the structural form of each layer of wave-absorbing material is a conical table structure, the distribution of each layer of wave-absorbing material is non-uniform, and the width of the top layer is diWidth of the bottom layer is di+1The height of each layer is H1/n, the transmission reflection coefficient corresponding to each layer of material is obtained through CST simulation, and the equivalent electromagnetic parameter corresponding to each layer of material is calculated according to the NRW methodnAnd mun，nAnd munThe dielectric constant and the magnetic permeability of the nth layer material are respectively set;
s22, calculating the scaling electromagnetic parameters of each layer of the wave-absorbing material of the prototype wave-absorbing material according to the calculation formula of the multilayer reflectivity:
in order to ensure that the reflectivity is unchanged, the surface impedance and the characteristic impedance of each layer of wave-absorbing material are ensured to be unchanged, namely:
Figure FDA0002664687210000021
and
Figure FDA0002664687210000022
before and after scaling, the ratio is kept unchanged;
in the formula, ZnIs the characteristic impedance of the n-th layer material, gammanIs the propagation constant of the n-th layer material, dnThe thickness of the nth layer material, and C is the speed of light;
selecting a scaling coefficient as s and a scaling frequency as sf;
if the reduced thickness is dnS, obtaining
Figure FDA0002664687210000023
And
Figure FDA0002664687210000024
kept constant, by transformation, i.e. before and after the required scalingnAndnkeeping the structure unchanged, and designing equivalent electromagnetic parameters of the wave absorption structure by using corresponding materials;
if the thickness ratio s' after the reduction ratio is kept is different from the reduction ratio coefficient s, and the reduction ratio thickness is dnS' at which time maintenance is required
Figure FDA0002664687210000025
And
Figure FDA0002664687210000026
meanwhile, the method is established and simplified as follows:
Figure FDA0002664687210000027
by means of the change in the direction of the axis,s n＝ns′/s，μs n＝μns'/s to obtain the corresponding dielectric constant under the scaled frequencys nAnd magnetic permeability mus n；
S23, constructing a scaling material with the same shape as the original wave-absorbing material by using a scaling theory, and theoretically designing the scaling electromagnetic parameters and the thickness of each layer of wave-absorbing material according to the impedance characteristic parameters.
2. The method for designing a high performance absorber according to claim 1, wherein in step S2:
the scaling material is dielectric wave-absorbing material or magnetic loss material.
3. The method for designing a high performance absorber according to claim 1, wherein in step S21:
during CST simulation, 3 sections are selected for simulation to obtain equivalent electromagnetic parameters of each section, then equivalent electromagnetic parameters of other sections are obtained by adopting a parabolic interpolation method, the 3 sections are respectively the 1 st section, the INT (n/2) th section and the nth section, wherein the INT is an integer function.
4. The method for designing a high performance absorber according to claim 1, wherein in step S23:
for the scaling design of the dielectric wave-absorbing material, s' is selected to ensure thats n＝n(ii) a When the principle that the shape of a scaled structure is the same is adopted, the scaled material of the non-uniform structure obtained by inversion of the equivalent structure is consistent with the dielectric constant of the original wave-absorbing material, meanwhile, when the dielectric constant changes smaller along with the increase of frequency, the structure does not need to be adjusted at the moment, only the equivalent structure design is needed, when the dielectric constant of the original wave-absorbing material has certain change, for the dielectric wave-absorbing material, only the volume addition ratio of wave-absorbing particles needs to be adjusted at the moment, and the volume addition ratio and the wave-absorbing particle type corresponding to each layer of wave-absorbing material are obtained through inversion.
5. The method for designing a high performance absorber according to claim 1, wherein in step S23:
for the scaling design of the magnetic wave-absorbing material, when s' and s are different, the requirement is satisfieds n＝ns′/s，μs n＝μns′/s。
6. The method according to claim 3, wherein in step S23:
for the filling type magnetic wave-absorbing material, interpolation fitting is carried out on the dielectric constant according to electromagnetic material electromagnetic parameter libraries with different volume ratios to obtain the dielectric constant of the uniformly distributed material, the equivalent medium theory is utilized to further obtain the preparation ratio of the corresponding wave-absorbing material, the corresponding wave-absorbing material is prepared according to the preparation ratio, and the relative error of the selected parameters in the design is within 10 percent.
7. The method according to claim 6, wherein the step S23 further comprises:
calculating the dielectric constant of the wave-absorbing material prepared according to the preparation proportion, and performing parameter fitting by adopting a third phase absorbent when the dielectric constant value has deviation from a target dielectric constant value;
and aiming at the third phase absorbent, calculating the electromagnetic parameters of the wave-absorbing material as follows:
Figure FDA0002664687210000031
in the formula, q is the volume addition ratio of the wave-absorbing particles,
Figure FDA0002664687210000032
is the dielectric loss tangent, tan, of the mixturemsTan, the dielectric loss tangent of the wave-absorbing particlesmtThe required electromagnetic parameters are obtained by introducing the third phase absorbent to adjust the dielectric constant of the material for the dielectric loss tangent value containing the third phase absorbent, and the third phase absorbent is dielectric wave-absorbing particles.
CN201711279118.2A 2017-12-06 2017-12-06 High-performance wave absorber design method based on scaling theory Active CN107968265B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201711279118.2A CN107968265B (en) 2017-12-06 2017-12-06 High-performance wave absorber design method based on scaling theory

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201711279118.2A CN107968265B (en) 2017-12-06 2017-12-06 High-performance wave absorber design method based on scaling theory

Publications (2)

Publication Number Publication Date
CN107968265A CN107968265A (en) 2018-04-27
CN107968265B true CN107968265B (en) 2020-12-22

Family

ID=61999524

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201711279118.2A Active CN107968265B (en) 2017-12-06 2017-12-06 High-performance wave absorber design method based on scaling theory

Country Status (1)

Country Link
CN (1) CN107968265B (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111380928B (en) * 2020-03-30 2022-12-02 北京工业大学 Reflection characteristic-based method for detecting wave-absorbing performance of carbon nanotube wave-absorbing material
CN111585034B (en) * 2020-06-02 2021-09-07 中国人民解放军军事科学院国防科技创新研究院 Design method of impedance matching type metamaterial
CN111695217B (en) * 2020-06-09 2021-12-28 西安交通大学 Wide-angle wave-absorbing structure design method based on additive manufacturing
CN111899820A (en) * 2020-08-07 2020-11-06 上海无线电设备研究所 Rapid design method of dielectric medium type composite absorbent
CN112611921B (en) * 2020-12-09 2022-12-23 上海无线电设备研究所 Atmospheric sound field simulation device and electromagnetic scattering characteristic test method thereof
CN112906156B (en) * 2021-02-08 2022-03-15 电子科技大学 Equivalent electromagnetic parameter extraction method of special-shaped honeycomb wave-absorbing structure
CN113960512B (en) * 2021-11-03 2023-03-14 电子科技大学 Deduction calculation method for equivalent electromagnetic parameters of rubber plate type wave-absorbing material

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1584695A1 (en) * 2004-04-06 2005-10-12 Efoam S.A. Method for joining a metal foam to a metal body
CN105224762A (en) * 2015-10-19 2016-01-06 上海无线电设备研究所 A kind of contracting based on electromagnetic parameter optimal design is than compound substance compound method
CN105304248A (en) * 2015-11-23 2016-02-03 上海无线电设备研究所 Preparation method of magnetic wave absorption patch shrinkage simulation composite material
CN106443207A (en) * 2016-10-28 2017-02-22 北京无线电计量测试研究所 Concentric conical TEM cell and terminal loads
CN106777627A (en) * 2016-12-02 2017-05-31 上海无线电设备研究所 A kind of honeycomb inhales the contracting of ripple plate than simulation material building method
CN107301301A (en) * 2017-07-06 2017-10-27 上海无线电设备研究所 A kind of building method of magnetic loss type contracting than absorbing material

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5258626A (en) * 1992-06-22 1993-11-02 The United States Of America As Represented By The Secretary Of The Air Force Superconducting optically reconfigurable electrical device
US7051945B2 (en) * 2002-09-30 2006-05-30 Nanosys, Inc Applications of nano-enabled large area macroelectronic substrates incorporating nanowires and nanowire composites
US7619562B2 (en) * 2002-09-30 2009-11-17 Nanosys, Inc. Phased array systems
CN106503311B (en) * 2016-10-09 2019-06-11 上海无线电设备研究所 Preparation method of the earth background electromagnetism contracting based on bio-based materials than material

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1584695A1 (en) * 2004-04-06 2005-10-12 Efoam S.A. Method for joining a metal foam to a metal body
CN105224762A (en) * 2015-10-19 2016-01-06 上海无线电设备研究所 A kind of contracting based on electromagnetic parameter optimal design is than compound substance compound method
CN105304248A (en) * 2015-11-23 2016-02-03 上海无线电设备研究所 Preparation method of magnetic wave absorption patch shrinkage simulation composite material
CN106443207A (en) * 2016-10-28 2017-02-22 北京无线电计量测试研究所 Concentric conical TEM cell and terminal loads
CN106777627A (en) * 2016-12-02 2017-05-31 上海无线电设备研究所 A kind of honeycomb inhales the contracting of ripple plate than simulation material building method
CN107301301A (en) * 2017-07-06 2017-10-27 上海无线电设备研究所 A kind of building method of magnetic loss type contracting than absorbing material

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
高Q值超薄完美吸波体设计方法研究;李思佳;《物理学报》;20131231;第62卷(第24期);第1-7页 *

Also Published As

Publication number Publication date
CN107968265A (en) 2018-04-27

Similar Documents

Publication Publication Date Title
CN107968265B (en) High-performance wave absorber design method based on scaling theory
CN104993249B (en) Single-pass band bilateral inhales ripple and is combined Meta Materials and its antenna house and antenna system
CN109167181B (en) Broadband periodic wave absorbing structure of graphical honeycomb unit
CN107958123B (en) Electromagnetic design method for broadband camouflage shielding wave absorber
CN108957603A (en) A kind of ultra wide band electromagnetic absorber based on propagating wave in multilayer sub-wavelength structure and super structure surface wave principle of reciprocity
CN111755835B (en) Broadband periodic wave absorbing structure based on magnetic substrate
CN111695217B (en) Wide-angle wave-absorbing structure design method based on additive manufacturing
CN110641130A (en) Preparation method of wave-absorbing foam for absorbing low-frequency electromagnetic waves
CN106332533A (en) Wave-absorbing metamaterial
CN113692212B (en) Multilayer wave absorber structure and application thereof
Zhou et al. Gradient carbonyl-iron/carbon-fiber reinforced composite metamaterial for ultra-broadband electromagnetic wave absorption by multi-scale integrated design
CN105789915B (en) Dual polarized antenna
CN201649340U (en) Multi-layer structure microwave dark room absorbing material filled with foam bulk blocks
JP2000507400A (en) Electromagnetic wave absorbing panel and its material
Gong et al. Design of ultra wideband microwave absorber effectual for objects of arbitrary shape
CN108682963A (en) It is a kind of with ultra-high frequency than multi-band frequency select construction design method
CN113013636A (en) Stepped broadband radar wave-absorbing structure based on composite material
Violi et al. A Compact Wide-band Absorber Based on Resistive FSS and Magnetic Materials
JP2021086865A (en) Carbon fiber-containing radio wave absorber and manufacturing method thereof
CN111029788A (en) Broadband metamaterial wave-absorbing structure with angle and polarization insensitivity
Zhang et al. Investigation of the graphene-paraffin composite absorbing coating in wide-band absorption under large-angle incidence of transverse magnetic waves
Lin et al. A low-profile metamaterial absorber with ultrawideband reflectionless and wide-angular stability
CN216312062U (en) Broadband pyramid wave-absorbing material
Meshram et al. Transmission line modeling (TLM) for evaluation of absorption in ferrite based multi layer microwave absorber
Ma et al. Design of band-stop frequency selective surface structure with large and stable reflection band

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant