CN107958105B - Method for reducing reflection of electromagnetic waves on metal surface by using plasma coating - Google Patents
Method for reducing reflection of electromagnetic waves on metal surface by using plasma coating Download PDFInfo
- Publication number
- CN107958105B CN107958105B CN201711099387.0A CN201711099387A CN107958105B CN 107958105 B CN107958105 B CN 107958105B CN 201711099387 A CN201711099387 A CN 201711099387A CN 107958105 B CN107958105 B CN 107958105B
- Authority
- CN
- China
- Prior art keywords
- plasma
- electromagnetic wave
- reflection
- coating
- plasma coating
- 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
Links
- 238000000576 coating method Methods 0.000 title claims abstract description 72
- 239000011248 coating agent Substances 0.000 title claims abstract description 66
- 238000000034 method Methods 0.000 title claims abstract description 44
- 239000002184 metal Substances 0.000 title claims abstract description 23
- 230000005540 biological transmission Effects 0.000 claims abstract description 17
- 230000001902 propagating effect Effects 0.000 claims abstract description 9
- 210000002381 plasma Anatomy 0.000 description 148
- 238000004364 calculation method Methods 0.000 description 10
- 239000000126 substance Substances 0.000 description 9
- 230000009471 action Effects 0.000 description 8
- 238000013461 design Methods 0.000 description 6
- 239000007789 gas Substances 0.000 description 6
- 238000011160 research Methods 0.000 description 6
- 238000010521 absorption reaction Methods 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 4
- 238000000342 Monte Carlo simulation Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 241000894007 species Species 0.000 description 2
- 241000208152 Geranium Species 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000009795 derivation Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000013178 mathematical model Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012821 model calculation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000000644 propagated effect Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
- G06F17/10—Complex mathematical operations
- G06F17/11—Complex mathematical operations for solving equations, e.g. nonlinear equations, general mathematical optimization problems
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2111/00—Details relating to CAD techniques
- G06F2111/10—Numerical modelling
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Pure & Applied Mathematics (AREA)
- Mathematical Optimization (AREA)
- Computational Mathematics (AREA)
- Mathematical Analysis (AREA)
- General Engineering & Computer Science (AREA)
- Data Mining & Analysis (AREA)
- Software Systems (AREA)
- Databases & Information Systems (AREA)
- Algebra (AREA)
- Operations Research (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- Geometry (AREA)
- Plasma Technology (AREA)
Abstract
A method for reducing the reflection of electromagnetic waves on the metal surface by utilizing a plasma coating, wherein the plasma coating which is coated with a plurality of layers of different media is used for analyzing and determining the parameters of the coated plasma coating according to the frequency characteristics of incident electromagnetic waves, and comprises the following steps: s1, preliminarily determining plasma coating parameters according to prior experience, and obtaining a plasma coating model according to the parameters; s2, combining the known incident electromagnetic wave equation and the plasma coating model obtained in S1, and establishing a model of the electromagnetic wave propagating in the plasma coating; s3, calculating the reflection and transmission coefficients of the incident electromagnetic wave on the interface layer by layer, and accumulating the reflection and transmission coefficients into a total electromagnetic wave reflection coefficient; s4, changing the plasma medium types for many times, adjusting the electron density of the plasma, changing the plasma coating thickness, repeating the step S3, observing the actual reflection condition of the electromagnetic wave, and selecting the coating parameters preferentially. The invention has the advantages that: the electromagnetic wave is absorbed to the maximum extent in the plasma coating, and less electromagnetic wave reflection is realized.
Description
Technical Field
The invention relates to the technical field of radar target electromagnetic scattering characteristic calculation, in particular to a method for reducing reflection of electromagnetic waves on a metal surface by using a plasma coating.
Background
By stealth aircraft, it is meant that the aircraft cannot be found by electromagnetic detectors such as radars. The essence of the method is that the aircraft completely or approximately completely absorbs the detected electromagnetic waves and does not reflect or reflects few electromagnetic waves. Multiple layers of plasma coatings of different materials and densities are a preferred option.
As shown in fig. 1, when a planar electromagnetic wave is incident on a multi-layer plasma coating, it is reflected and refracted at the interface between different media, and finally reaches the metal surface to which the plasma coating is attached. Ideally, the electromagnetic waves are not reflected when they reach the metal surface, which means that the plasma coating has completely absorbed the incident electromagnetic waves, successfully achieving the goal of aircraft stealth.
A fourth state of the plasma, which is referred to as the presence of substances other than gases, liquids and solids, is an ionized gaseous substance consisting of a large number of positive and negative charges. The action of electromagnetic waves and plasmas has the phenomena of frequency drift, nonlinear absorption of energy and the like which are different from the action of traditional substances, and the action mechanism of the electromagnetic waves and the plasmas is still not completely explained so far. In the stealth design of the aircraft, the research of reducing the reflection of electromagnetic waves by using a proper plasma layer design has important significance.
The existing method is mainly to extract equivalent parameters of plasma to simplify the solution. The main approach is by theoretical analysis methods, which have the disadvantage that only extremely simple solutions of idealized geometric models can be carried out.
By establishing a dynamic plasma sheath electron density mathematical model, Geranium et al of the Segan electronics science and technology university adopts a WKB (Wentzel-Kramers-Brillouin method) method to obtain electromagnetic wave propagation characteristics. Further establishing a dynamic plasma sheath electromagnetic wave propagation method (Shihui, Yao Bo, Li Xiaoping, Yanmin, Liuyanming, a fast dynamic plasma sheath electric wave propagation calculation method, CN105260507,2016, 1/20). But the method can only calculate a one-dimensional plasma electromagnetic scattering model. The Lejiang stile et al of the university of Western's electronics science and technology adopts a Monte Carlo method to randomly simulate plasma into a plurality of ellipsoid scatterers, and obtains a scattering field of a far-field region (Lejiang stile, Yang fei, Guo Li Xin, Sunwu, Wang Shi Jun, Zhou Xinbo, an electromagnetic scattering simulation method for ablating the surface of an aircraft, invented patent, CN105574296,2016, 5.11.s.). And repeatedly calculating the superposition of a plurality of samples to obtain the average value of the far field. However, this method is based on the complete monte carlo method and lacks effective theoretical support. In a patent of 'electromagnetic scattering analysis method of ultra-high-speed flight target' published in 2013 by Cheng Li shan et al, Nanjing university of science and engineering, aiming at non-uniform plasma wrapped around the ultra-high-speed flight target, an approximation method of volume surface integration is adopted, the scattering characteristic under electromagnetic wave incidence is theoretically deduced, and a typical blunt cone target radar scattering cross section numerical calculation result is given. However, this patent does not show an optimized plasma parameter setting to achieve the desired electromagnetic wave scattering effect (chen shang, fan juhong, great will, poem, shenjun, chen feng, huyanlong, kayakn, dawn east, electromagnetic scattering analysis method of ultra-high speed flight target, nanjing university of science and engineering, patent No. CN103198227A, 7/1 2013). However, the theoretical derivation of the method is complex, only a static plasma sheath model can be calculated, and the specific application background is lacked.
Among the methods based on numerical calculation, there are a discretization numerical calculation method such as finite difference of time domain, and a model method of photon-to-Plasma particle collision based on microscopic angles (B.T. Nguyen, C.Furse, J.J.Simpson, A3-D stored FDTD model electric Wave Propagation in Magnetized Lonosphere Plasma, IEEE Transactions on Plasma Propagation, vol.63, No.1,2015.) (A.B.Petrin. on the Transmission of microwave Through Plasma Layers, IEEE Transactions on Plasma Science, vol.28, No.3, 2000.). Both of these methods are typically very computer resource intensive and cannot be solved for larger electrical dimension models. Theoretically, the two methods can give relatively accurate calculation results, but in actual model calculation, the surface of the aircraft and the surrounding environment are relatively complex, and the solution of the method cannot give accurate electromagnetic field propagation description. Further, the solution is obtained by equating the plasma layer to a substance having a constant dielectric constant and using propagation of electromagnetic waves in the substance having a complex dielectric constant.
The theory solution of electromagnetic scattering of electromagnetic waves under the condition of multi-layer plasma incident at any angle is calculated by adopting an equivalent complex dielectric constant method, which is provided by M.Laroussi et al of the national university of Tennessee, USA. (M.Laroussi, J.R.Roth.numerical calibration of the Reflection, Absorption, and Transmission of Microwaves by a Non-uniform Plasma Slab [ J ]. IEEE Transactions on Plasma Sci-science, vol.21, No.4,1993.). However, in the research, only the electromagnetic scattering field of an ideal plasma parameter distribution model is given, and the research on the electromagnetic scattering field by plasma properties is lacked. The o.sakai group at kyoto university in japan studied the scattering properties of a plasma substance having a multilayer periodic structure formed of plasma by a complex dielectric constant method. (O.Sakai, L, Tachiba. Properties of Electromagnetic Wave Propaga-station emitting in 2-D Periodic Plasma Structures, IEEE Transac-stations on Plasma Science, vol.35, No.35,2007). In the research, the scattering characteristics of plasmas with different properties and the influence of various plasma physical parameters such as electron density on the electromagnetic scattering characteristics are analyzed.
The method is completely based on theoretical research of equivalent complex dielectric constant, and lacks the specific background of electromagnetic scattering application of plasma around the ultrahigh-speed flying target. The method is intuitive to understand in principle and greatly reduces the calculation amount. How to adopt a proper electromagnetic wave and plasma action solving method and set a proper plasma model and parameters to obtain the smaller reflection of the electromagnetic wave on the surface of the aircraft with the plasma layer is always a difficult problem in the field of balance theoretical analysis, numerical calculation and practical application.
Disclosure of Invention
The invention aims to provide a method for reducing reflection of electromagnetic waves on a metal surface by using a plasma coating, which is applied to research of invisible aircrafts and is used for reducing reflection of the electromagnetic waves on the metal surface by adjusting the material and density of the plasma coating to absorb the energy of incident electromagnetic waves as much as possible.
In order to solve the above technical problems, the present invention provides a method for reducing the reflection of electromagnetic waves on a metal surface by using a plasma coating, which analyzes and determines the electron frequency, the collision frequency, the molecular density of plasma gas, the collision cross-sectional area of plasma, the electron mass of plasma and the parameters of applied voltage of the coated plasma according to the frequency characteristics of incident electromagnetic waves, comprising the following steps:
s1, preliminarily determining plasma coating parameters according to prior experience, and obtaining a plasma coating model according to the parameters;
s2, combining the known incident electromagnetic wave equation and the plasma coating model obtained in S1, and establishing a model of the electromagnetic wave propagating in the plasma coating;
s3, calculating the reflection and transmission coefficients of the incident electromagnetic wave on the interface layer by layer, and accumulating the reflection and transmission coefficients into a total electromagnetic wave reflection coefficient;
s4, changing the plasma medium types for many times, adjusting the electron density of the plasma, changing the plasma coating thickness, repeating the step S3, observing the actual reflection condition of the electromagnetic wave, and selecting the coating parameters preferentially.
In the above method for reducing reflection of electromagnetic waves on a metal surface by using plasma coating, the electromagnetic waves are planar electromagnetic waves.
In the above method for reducing reflection of electromagnetic waves on a metal surface by using a plasma coating, the coating parameters include: plasma electron frequency, collision frequency, plasma gas molecular density, plasma collision cross-sectional area, plasma electron mass, and electron applied voltage.
In the method for reducing the reflection of electromagnetic waves on the metal surface by using the plasma coating, the complex dielectric constant of the plasma coating with uniformly distributed density is as follows:
wherein ε 'and ε' represent the real and imaginary parts, respectively, of the equivalent relative permittivity in the plasmarRepresenting the equivalent complex dielectric constant. Omega and omega in the formulap、N0、σe、kB、me、TeAnd c represents the frequency of incident electromagnetic waves, the electron frequency of plasma, the molecular density of plasma gas, the cross-sectional area of plasma collision, the boltzmann constant, the electron mass of plasma, the voltage applied by electrons, and the speed of light in vacuum, respectively.
In the above method for reducing reflection of electromagnetic waves on a metal surface by using plasma coating, the equation of the incident electromagnetic wave in step S2 is:
wherein，E0And
the initial field strength and direction of the incident electromagnetic wave and the real-time field strength and direction, respectively, beta is a phase constant, and-z represents a planar electromagnetic wave propagating along + z.
In the above method for reducing reflection of electromagnetic waves on a metal surface by using plasma coating, the impedance of the interface between adjacent plasma coatings in step S3 is:
wherein Z is the wave impedance, l is the coordinate information, and subscripts n-1 and n are the plasma layer number. Thetat＜n-1＞Is the angle of refraction at the interface between the (n-2) th and (n-1) th layers.
The resistance of the (n-1) th and n-th layers with respect to all the preceding layers 1 to n-2 can thus be solved.
The invention has the advantages and beneficial effects that:
(1) the electromagnetic wave can be incident into the plasma coating to the maximum extent.
(2) The electromagnetic wave can be propagated in the plasma to the maximum extent.
(3) The electromagnetic wave is absorbed to the maximum extent in the plasma coating, and less electromagnetic wave reflection is realized.
Drawings
FIG. 1 is a schematic diagram of electromagnetic wave propagation in a multi-layer plasma region.
Fig. 2 is a schematic diagram of an embodiment.
FIG. 3 is a graph showing the reflectance of electromagnetic waves incident on a uniform plasma layer and a non-uniform plasma layer.
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.
The real part of the plasma equivalent complex permittivity is closely related to the plasma electron density, the plasma species, and the collision frequency. The real part of the dielectric constant of the plasma is in direct proportion to the electron density. When the plasma electron density is small, the plasma appears as a high-loss dielectric substance with a relative dielectric constant real part between 0 and 1 and a negative imaginary part. As the electron density of the plasma increases, the real part and the imaginary part of the relative dielectric constant of the plasma respectively and gradually increase, in this case, most of the electromagnetic waves are reflected back to the original substance on the surface of the plasma, and a small part of the electromagnetic waves incident into the plasma are rapidly absorbed and sharply attenuated. The plasma exhibits a strong ionization property in this case, and the electromagnetic wave is hard to transmit.
Based on the theory, a design concept of multilayer plasma on the surface of the aircraft is provided. The electromagnetic wave can be incident into the plasma to the maximum extent, so that less electromagnetic wave reflection is realized, and the plasma can be ensured to realize maximum energy absorption on the transmitted electromagnetic wave. The multilayer plasma design structure provided by the invention enables electromagnetic waves to be incident into plasma to the maximum extent, and meanwhile, the electromagnetic waves can reach the minimum reflection between the interfaces of each plasma layer by adjusting the electron density and other parameters of the multilayer plasma. The design concept ensures that the electromagnetic wave can be maximally transmitted in the plasma, and meanwhile, the electromagnetic wave transmitted in the plasma can be maximally absorbed, so that smaller electromagnetic wave reflection is realized.
The guidance idea of this embodiment is to set up two plasma layers to give different parameter attributes, set up plasma electron density and thickness through adjusting, realize less electromagnetic wave reflection in whole frequency channel. Therefore, the smaller electromagnetic wave reflection coefficient under the condition that the double-layer plasma layers with different properties cover the surface of the aircraft is realized. As shown in fig. 2, the aircraft surface was coated with 2 plasma coatings at thicknesses d1 and d2, respectively, and an angle of incidence θ. The plasma coating thickness and the plasma coating density parameter are adjustable, and the bottom of the plasma coating is a metal layer used for simulating the actual aircraft target surface. The plasma substance is composed of helium, incident electromagnetic waves are X-band 8-12GHz frequency electromagnetic waves, and physical parameters of the plasma coating are changed by adjusting the electron density and the plasma coating thickness of the two layers of plasma coatings respectively, so that the equivalent impedance of the plasma coating is changed, and the absorption, reflection and transmission characteristics of the plasma on the electromagnetic waves are adjusted. Here, the plasma thickness refers to a distance l of an electromagnetic wave in a plasma propagation formula.
The invention provides a method for reducing the reflection of electromagnetic waves on a metal surface by using a plasma coating, which comprises the following steps.
And S1, preliminarily determining the parameters of the plasma coating according to the prior experience, and obtaining a plasma coating model according to the parameters.
The complex dielectric constant of the plasma coating with uniformly distributed density is:
wherein ε 'and ε' represent the real and imaginary parts, respectively, of the equivalent relative permittivity in the plasmarRepresenting the equivalent complex dielectric constant. L, omega in the formulap、N0、σe、kB、me、TeAnd c represents plasma thickness, incident electromagnetic wave frequency, plasma electron frequency, plasma gas molecular density, plasma collision cross-sectional area, Boltzmann constant, electron mass of plasma, electron applied voltage, and light velocity in vacuum, respectively.
In this example, it was determined that the plasma species consisted of helium and the incident electromagnetic wave was an X-band 8-12GHz frequency electromagnetic wave, then the plasma gas molecular density N alone in equation (1)0The plasma thickness l is a variable that can be used to adjust the reflection coefficient.
And S2, combining the known incident electromagnetic wave equation and the plasma coating model obtained in S1, and establishing a model of the electromagnetic wave propagating in the plasma coating. The known equation for incident electromagnetic waves is:
wherein E is0And
the initial field strength and direction of the incident electromagnetic wave and the real-time field strength and direction, respectively, beta is a phase constant, and-z represents a planar electromagnetic wave propagating along + z.
The electromagnetic wave propagation model in the plasma coating follows the electromagnetic wave multilayer reflection and propagation model, and at each layer interface, the electromagnetic wave reflection and transmission coefficients conform to R ═ Z (Z)t-Z0)/(Z0+Zt) And T ═ 2Zt/(Zt+Z0) And (4) a formula.
And S3, calculating the reflection and transmission coefficients of the incident electromagnetic wave at the interface layer by layer, and accumulating the reflection and transmission coefficients into a total electromagnetic wave reflection coefficient.
The action situation of the plane electromagnetic wave under the condition of vertical incidence is observed, namely the situation that theta is zero degree in figure 2. Firstly, the collision frequency of plasma electrons and neutral particles is set to be 2GHz, and the corresponding collision section is 10-20/m2The thickness of the plasma layer was 0.1 m. The plasma densities of the two layers were compared for a uniform case and a non-uniform case, respectively, with these parameters observed to be constant. One example of which is shown in fig. 3.
The impedance at the interface of adjacent plasma coatings was:
wherein Z is the wave impedance, l is the coordinate information, and subscripts n-1 and n are the plasma layer number. Thetat＜n-1＞Is the angle of refraction at the interface between the (n-2) th and (n-1) th layers.
Where θ is zero degrees, Z1And Z2Respectively the plasma equivalent impedance, beta, of the first and second layers2Is the electromagnetic wave propagation constant of the second layer plasma. Thus, the impedance of the electromagnetic wave incident surface can be analogized by ZtSubstituting the formula again to set Z0For air electromagnetic wave impedance, i.e. obtaining total impedance Zin：
First, the electron density of the plasma is set to change at 1022/m3And 1024/m3Interval and value are same, every 1022/m3Scanning and solving the electron density to obtain the total equivalent impedance under the uniform condition, and using the relation R (Z) between the reflection coefficient and the transmission coefficient of the electromagnetic wave and the impedance of the electromagnetic wavet-Z0)/(Z0+Zt) And T ═ 2Zt/(Zt+Z0) Then, the reflection coefficient and the transmission coefficient of the corresponding electromagnetic wave frequency band can be obtained as follows:
and
s4, changing the plasma medium types for many times, adjusting the electron density of the plasma, changing the plasma coating thickness, repeating the step S3, observing the actual reflection condition of the electromagnetic wave, and selecting the coating parameters preferentially.
Setting the electron density of two plasma layers to be different, and fixing the plasma density of the II-th layer to be 1024/m3For the I layer plasma density in the interval 1022/m3And 1024/m3Changed every 1022/m3And performing scanning calculation. Minimum electromagnetic wave reflection efficiency at a plasma density of 1023/m3Is obtained when the compound is used.
In the above method for reducing reflection of electromagnetic waves on a metal surface by using plasma coating, the electromagnetic waves are planar electromagnetic waves.
In the above method for reducing reflection of electromagnetic waves on a metal surface by using plasma coating, the equation of the incident electromagnetic wave in step S2 is:
wherein,
and
the initial field strength and direction of the incident electromagnetic wave and the real-time field strength and direction, respectively, beta is a phase constant, and-z represents a planar electromagnetic wave propagating along + z.
The technical scheme of the invention is explained in detail in the above with reference to the attached drawings, and a non-uniform plasma layer design method is provided. By considering the plasma layer as a transmission medium with complex dielectric constant and magnetic conductivity and combining with a transmission line theory, the electromagnetic wave field intensity and phase information in the electromagnetic wave transmission process are calculated, and the final reflection coefficient under the action condition of the electromagnetic wave and the plasma layer is solved. And finally realizing smaller electromagnetic wave reflection coefficient by adjusting the attribute parameters and the thickness of the plasma layer. The method is a simple and convenient method for solving the action of the electromagnetic waves and the plasma, and a large amount of numerical calculation and a complex modeling process are avoided through visual understanding of the action of the electromagnetic waves and the plasma.
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 (5)
1. A method for reducing the reflection of electromagnetic waves on a metal surface by using a plasma coating, which is characterized in that the metal surface is coated with a plurality of layers of plasma coatings with different media, and the plasma electron frequency, the collision frequency, the plasma gas molecular density, the plasma collision cross section area, the plasma electron quality and the loaded voltage parameters of the coating are analyzed and determined according to the frequency characteristics of incident electromagnetic waves, and the method comprises the following steps:
s1, preliminarily determining plasma coating parameters according to prior experience, and obtaining a plasma coating model according to the parameters;
s2, combining the known incident electromagnetic wave equation and the plasma coating model obtained in S1, and establishing a model of the electromagnetic wave propagating in the plasma coating; the model of the electromagnetic wave propagating in the plasma coating follows the electromagnetic wave multilayer reflection and propagation model;
s3, calculating the reflection and transmission coefficients of the incident electromagnetic wave on the interface layer by layer, and accumulating the reflection and transmission coefficients into a total electromagnetic wave reflection coefficient;
s4, changing the types of plasma media for many times, adjusting the electron density of plasma, changing the thickness of the plasma coating, repeating the step S3, observing the actual reflection condition of electromagnetic waves, and selecting coating parameters from the electromagnetic waves;
the impedance of the adjacent plasma coating interface in the step S3 is:
wherein Z is the wave impedance, l is the coordinate information, subscripts n-1 and n are the plasma layer number, thetat＜n-1＞Is the angle of refraction at the interface between the (n-2) th and (n-1) th layers.
2. The method of claim 1, wherein the electromagnetic wave is a planar electromagnetic wave.
3. A method for reducing the reflection of electromagnetic waves at a metal surface using a plasma coating as claimed in claim 1 or 2, wherein said coating parameters include: plasma electron frequency, collision frequency, plasma gas molecular density, plasma collision cross-sectional area, plasma electron mass, and applied voltage.
4. A method for reducing reflection of electromagnetic waves at a metal surface using a plasma coating as claimed in claim 1 or 2, wherein the complex dielectric constant of the plasma coating having a uniform density distribution is:
wherein ε 'and ε' represent the real and imaginary parts, respectively, of the equivalent relative permittivity in the plasmarExpresses equivalent complex dielectric constant, omega and omega in the formulap、N0、σe、kB、me、TeAnd c represents the frequency of incident electromagnetic waves, the electron frequency of plasma, the molecular density of plasma gas, the cross-sectional area of plasma collision, the boltzmann constant, the electron mass of plasma, the voltage applied by electrons, and the speed of light in vacuum, respectively.
5. The method for reducing the reflection of electromagnetic waves on metal surfaces by using plasma coating according to claim 1 or 2, wherein the equation of the incident electromagnetic wave in step S2 is as follows:
wherein,
and
the initial field strength and direction of the incident electromagnetic wave and the real-time field strength and direction, respectively, beta is a phase constant, and-z represents a planar electromagnetic wave propagating along + z.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711099387.0A CN107958105B (en) | 2017-11-09 | 2017-11-09 | Method for reducing reflection of electromagnetic waves on metal surface by using plasma coating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711099387.0A CN107958105B (en) | 2017-11-09 | 2017-11-09 | Method for reducing reflection of electromagnetic waves on metal surface by using plasma coating |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107958105A CN107958105A (en) | 2018-04-24 |
| CN107958105B true CN107958105B (en) | 2021-06-04 |
Family
ID=61964470
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711099387.0A Active CN107958105B (en) | 2017-11-09 | 2017-11-09 | Method for reducing reflection of electromagnetic waves on metal surface by using plasma coating |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107958105B (en) |
Families Citing this family (5)
| 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 |
| CN111881609B (en) * | 2020-07-31 | 2024-02-02 | 北京环境特性研究所 | Configuration method and device for stealth parameters of plasma material |
| CN113128050B (en) * | 2021-04-21 | 2023-04-25 | 西安电子科技大学 | Plasma electron density and collision frequency combined diagnosis method based on wave impedance invariant point |
| CN113504414B (en) * | 2021-06-23 | 2022-05-03 | 电子科技大学 | Method and device for detecting plasma complex dielectric constant transient microwave transmission |
| CN114980466A (en) * | 2022-04-02 | 2022-08-30 | 哈尔滨工业大学 | Method for realizing electromagnetic wave focusing based on non-uniform plasma structure |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103198227A (en) * | 2013-04-18 | 2013-07-10 | 南京理工大学 | Electromagnetic scattering analyzing method for superspeed flight targets |
| CN105653747A (en) * | 2014-11-14 | 2016-06-08 | 南京理工大学 | Simulation method for super speed aircraft conformal sub-grid electromagnetic scattering characteristic analysis |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9483603B2 (en) * | 2014-06-02 | 2016-11-01 | Oracle International Corporation | Micro-benchmark analysis optimization for microprocessor designs |
| CN106158198B (en) * | 2015-11-25 | 2019-01-08 | 上海无线电设备研究所 | A kind of contracting of wideband is than analog composite material preparation method |
| CN106572625A (en) * | 2016-11-09 | 2017-04-19 | 上海无线电设备研究所 | Novel reflection-absorption integrated electromagnetic shielding structure |
-
2017
- 2017-11-09 CN CN201711099387.0A patent/CN107958105B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103198227A (en) * | 2013-04-18 | 2013-07-10 | 南京理工大学 | Electromagnetic scattering analyzing method for superspeed flight targets |
| CN105653747A (en) * | 2014-11-14 | 2016-06-08 | 南京理工大学 | Simulation method for super speed aircraft conformal sub-grid electromagnetic scattering characteristic analysis |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107958105A (en) | 2018-04-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107958105B (en) | Method for reducing reflection of electromagnetic waves on metal surface by using plasma coating | |
| CN107942309B (en) | Rapid calculation method for electromagnetic scattering of ultrahigh-speed target in thin atmosphere | |
| Xu et al. | Evaluations of plasma stealth effectiveness based on the probability of radar detection | |
| CN108152799B (en) | Method for rapidly calculating radar scattering cross section of hypersonic aircraft | |
| CN109581340A (en) | A kind of plasma electromagnetic scattering modeling method based on time domain Shooting and bouncing rays | |
| Zhang et al. | Study of attenuation characteristics of electromagnetic waves in multilayer plasma slabs | |
| Liu et al. | PO calculation for reduction in radar cross section of hypersonic targets using RAM | |
| Zhang et al. | Establishment of a wideband radar scattering center model of a plasma sheath | |
| Lu et al. | A study on zoning coating method of absorbing materials for stealth aircraft | |
| He et al. | Numerical investigation on interference and absorption of electromagnetic waves in the plasma-covered cavity using FDTD method | |
| Wang et al. | Studies on the effects of the plasma wake flow fields of hypersonic reentry blunt cone on electromagnetic wave | |
| CN115879307A (en) | Near-field simulation method for electromagnetic scattering characteristics of plasma target | |
| CN112986943B (en) | Method for calculating electromagnetic scattering of honeycomb composite material target | |
| Colliander et al. | Electromagnetic scattering from rough surface using single integral equation and adaptive integral method | |
| CN107301301B (en) | Construction method of magnetic loss type shrinkage ratio wave-absorbing material | |
| Ding et al. | Research on EM shielding mechanism of the plasma-sheath-covered target | |
| Shen et al. | Research on the Reflection Characteristics of the Broadband Electromagnetic Wave in Nonuniform Plasma | |
| CN112257261B (en) | Antenna, aircraft platform and plasma sheath integrated simulation analysis method | |
| Gao et al. | Research on electromagnetic scattering characteristics of flexible stealth material based on its 3D model | |
| Lai et al. | Attenuation characteristics of electromagnetic waves in plasma generated by coating radionuclide on surface structures | |
| Khalaj-Amirhosseini | Use of dielectric inhomogeneous planar layers as optimum microwave absorbers | |
| CN113933840A (en) | Synthetic aperture radar imaging method for high-speed aircraft platform under plasma sheath | |
| CN104657527B (en) | The Analysis of Electromagnetic Scattering method of stealthy airbound target is applied in ultrahigh speed scumbling | |
| Ma et al. | Echo attenuation characteristics of a vehicle covered with the inhomogeneous plasma sheath in terahertz band | |
| Jia et al. | Field discrete Monte Carlo simulation of electromagnetic scattering characteristics of plasma sheath |
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 |