CN115077302B - Radar stealth external member based on metamaterial - Google Patents
Radar stealth external member based on metamaterial Download PDFInfo
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- CN115077302B CN115077302B CN202210990840.1A CN202210990840A CN115077302B CN 115077302 B CN115077302 B CN 115077302B CN 202210990840 A CN202210990840 A CN 202210990840A CN 115077302 B CN115077302 B CN 115077302B
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- photonic crystal
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F41—WEAPONS
- F41H—ARMOUR; ARMOURED TURRETS; ARMOURED OR ARMED VEHICLES; MEANS OF ATTACK OR DEFENCE, e.g. CAMOUFLAGE, IN GENERAL
- F41H3/00—Camouflage, i.e. means or methods for concealment or disguise
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
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- General Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Aiming, Guidance, Guns With A Light Source, Armor, Camouflage, And Targets (AREA)
Abstract
The invention relates to a metamaterial-based radar stealth external member, which comprises a first stealth external member sleeved on a radar vehicle and a second camouflage external member sleeved on a radar, wherein the first stealth external member comprises a radar wave-absorbing base layer and a photonic crystal infrared stealth layer etched on the radar wave-absorbing base layer; the second camouflage kit comprises a photonic crystal infrared stealth layer and a radar wave photonic crystal stealth layer etched above the photonic crystal infrared stealth layer; the radar wave photonic crystal stealth layer is a metamaterial with a periodic dielectric structure formed by etching two semiconductor dielectric materials, and the radar wave photonic crystal stealth layer has a photonic band gap of a radar band and can simultaneously select and pass the radar band with a certain frequency in the photonic band gap. The photonic crystal is introduced with defects to realize the selection and the passing of a radar wave band with a certain frequency in a photonic band gap, and the photonic crystal material on the outer layer of the radar can be used as camouflage to be applied to a radar stealth, so that the method has important significance in improving the survival probability of weaponry.
Description
Technical Field
The invention relates to the technical field of military camouflage, in particular to a radar stealth suite based on a metamaterial.
Background
With the continuous progress of science, military reconnaissance technology is developed rapidly, on one hand, the resolution ratio of imaging equipment is higher and higher, the action distance is farther and farther, and radar vehicles are listed and lacked by enemies and can be eliminated at any time if stealth protection is not carried out on the radar vehicles; on the other hand, the detection band is further expanded, and the detection, aiming and accurate attack weapons on visible light, infrared band and radar wave are already put into military application and even civil market.
The existing radar stealth usually adopts a metal shielding mode, and metal cannot have a good compatible effect on own radar waves, and as an artificial periodic structure material, a photonic crystal has an excellent photonic band gap characteristic. The photonic crystal is widely applied to realizing stealth of visible and infrared bands, but the photonic crystal realizes stealth of the visible and infrared bands by reflecting the bands of attachments per se and cannot be directly applied to stealth of radar waves.
Disclosure of Invention
The invention aims to solve the problems and provide a radar stealth kit based on metamaterials.
In order to realize the purpose, the invention is realized by the following technical scheme: a radar stealth suite based on a metamaterial comprises a first stealth suite sleeved on a radar vehicle and a second camouflage suite sleeved on the radar, wherein the first stealth suite and the second camouflage suite provide full stealth of the vehicle and the radar in microwave, visible light and infrared wave bands while ensuring that the vehicle and the radar can normally work; the second camouflage kit comprises a photonic crystal infrared stealth layer and a radar wave photonic crystal stealth layer etched above the photonic crystal infrared stealth layer; the photonic crystal infrared stealth layer is a metamaterial with a periodic dielectric structure formed by etching two semiconductor dielectric materials and has a photonic band gap of visible light and infrared bands; the radar wave photonic crystal stealth layer is made of a metamaterial with a periodic dielectric structure formed by etching two semiconductor dielectric materials, and the radar wave photonic crystal stealth layer is provided with a photonic band gap of a radar wave band and can simultaneously select and pass the radar wave band with a certain frequency in the photonic band gap.
Furthermore, the radar wave-absorbing base layer is prepared by coating wave-absorbing materials on non-woven fabrics by a coating method, and the wave-absorbing materials are composed of graphene, magnetic metal and conductive high polymer.
In particular, the semiconducting dielectric material is selected from silicon, tellurium, selenium, germanium or a semiconducting compound, while the refractive index difference between the two dielectric materials is ensured.
Further, the periodic dielectric structure has a periodic structure in one direction and is uniform in the other two directions.
Still further, the periodic dielectric structure is a periodic structure having periodicity in two directions and uniformity in the other direction.
Further, the periodic dielectric structure has a periodic structure in three directions.
In particular, the radar wave photonic crystal stealth layer realizes the selection and the passing of a radar wave band with a certain frequency in a photonic band gap by introducing defects into the photonic crystal, wherein the defects comprise line defects and point defects.
Further, the line defects are realized by changing the dielectric constant of the adjacent semiconductor dielectric material in the complete lattice in the direction of the periodic structure.
Still further, the point defect is realized by symmetrically changing the size of the etching radius of the semiconductor dielectric material.
Compared with the prior art, the invention has the beneficial effects that:
the band gap characteristics of the photonic crystal are applied to the field of military stealth camouflage, the camouflage effect of visible light and infrared bands is obtained, meanwhile, defects are introduced into the photonic crystal to realize the selection and the passing of radar bands with certain frequency in the photonic band gap, and the photonic crystal material on the outer layer of a radar can be used as camouflage
The radar stealth protective film is applied to radar stealth, and has important significance for protecting important military targets of our army and improving the survival probability of weaponry.
Drawings
FIG. 1 is a schematic diagram of a one-dimensional photonic crystal structure according to the present invention;
FIG. 2 is a schematic diagram of a two-dimensional photonic crystal and transmission spectra according to the present invention;
FIG. 3 is a schematic representation of a two-dimensional defect photonic crystal (increasing the radius of the point defect) and transmission spectra of the present invention;
FIG. 4 is a schematic diagram of a two-dimensional defect photonic crystal (reducing the radius of the point defect) and a transmission spectrum of the present invention.
Detailed Description
The invention will be described in further detail with reference to examples of embodiments shown in the drawings, which should not be construed as limiting the invention in any way.
The invention aims to realize the stealth of radar through a photonic crystal, the photonic crystal is an artificial periodic structure material, the photonic crystal has excellent photonic band gap characteristics, no photonic state exists in the photonic band gap, the spontaneous radiation of electromagnetic waves with the frequency falling in the photonic band gap can be completely inhibited, the photonic crystal is a periodic dielectric medium structure, the photonic crystal is divided into a one-dimensional photonic crystal, a two-dimensional photonic crystal and a three-dimensional photonic crystal according to the number of periodicity in the direction, the reflection spectrum and the transmission spectrum of the photonic crystal with the finite periodic structure can be conveniently calculated aiming at a one-dimensional photonic crystal characteristic matrix method, the energy band structure can be conveniently calculated, and compared with a plane wave expansion method, the energy band of dispersion and a consumed material can also be calculated:
referring to FIG. 1, when an incident plane wave is at an angle
When the electromagnetic wave is incident from the medium 1 to the surface of the medium 2, a reflected wave and a transmitted wave are generated on the incident surface, if the tangential components of the electric field and the magnetic field of the electromagnetic wave in the medium 1 and the medium 2 are assumed to be respectively
And
the refractive indices of the two media are
And
angle of refraction in Medium 2Is composed of
The thickness of the medium 1 is
The thickness of the medium 2 is
Then, the electric field and the magnetic field of the two media satisfy the following relationship:
wherein the content of the first and second substances,
(ii) a For the one-dimensional photonic crystal formed by a multilayer structure, the above formulas can be multiplied in sequence layer by layer to obtain the product
A feature matrix of the layer structure. Suppose that
Layer and the first
The tangential components of the electric and magnetic fields in the layer medium are
And
then, then
In the formula
Is the first
The feature matrix of the layer medium, the total feature matrix is:
so that the electromagnetic wave passes through
The characteristic equation after layering a one-dimensional photonic crystal is:
where the electromagnetic waves are
Reflectivity on the surface of the layer medium
Comprises the following steps:
transmittance of light
Comprises the following steps:
wherein:
，
。
thus can be obtained by changing the refractive index of two media to
And
and the thickness of the medium 1 is
Thickness of medium 2
Realizing transmittance
The total reflection of the specific wave band is 0, the band gap characteristic of the photonic crystal is applied to the military camouflage field based on the photonic band gap characteristic, the camouflage effect on visible light and infrared wave bands is obtained, meanwhile, the total reflection of the radar wave band is realized, the attachment can be camouflaged or a false target is realized, and the specific structure is as follows:
a radar stealth suite based on a metamaterial comprises a first stealth suite sleeved on a radar vehicle and a second camouflage suite sleeved on the radar, wherein the first stealth suite and the second camouflage suite provide full stealth of the vehicle and the radar in microwave, visible light and infrared wave bands while ensuring that the vehicle and the radar can normally work;
aiming at the radar wave-absorbing base layer, the radar wave-absorbing base layer is prepared by coating wave-absorbing materials on non-woven fabrics by a coating method, wherein the wave-absorbing materials consist of graphene, magnetic metal and conductive high polymer;
the photonic crystal infrared stealth layer is formed by etching two semiconductor dielectric materials to form a metamaterial with a periodic dielectric structure, the metamaterial has photonic band gaps of visible light and infrared bands, the semiconductor dielectric materials are selected from silicon, tellurium, selenium, germanium or semiconductor compounds, and different refractive indexes between the two dielectric materials are ensured to further realize the photonic band gaps of the photonic crystal infrared stealth layer in the visible light and infrared bands.
The second camouflage kit comprises a photonic crystal infrared stealth layer and a radar wave photonic crystal stealth layer etched above the photonic crystal infrared stealth layer; the radar wave photonic crystal stealth layer is made of two semiconductor dielectric materials which are etched to form a metamaterial with a periodic dielectric structure, and due to the fact that the photonic crystal achieves stealth of visible light and infrared wave bands and reflects the wave bands of attachments, if stealth directly used for radar wave bands inevitably causes incompatibility of own radar waves, the radar wave photonic band stealth layer with the radar wave bands needs to be capable of passing through the radar wave bands with certain frequency in the photonic band gaps.
Aiming at defect state photon selection of the photonic crystal, radar wave photonic crystal stealth layers realize the selection of radar wave bands with certain frequency in a photonic band gap by introducing defects in the photonic crystal, wherein the defects comprise line defects and point defects, and referring to fig. 2, a two-dimensional square photonic crystal structure can have forbidden bands (a complete lattice consists of 5 continuous lattice points) for TM modes, and the forbidden bands appear at f =1.53 × 10 14 Hz to f =2.08 x 10 14 Hz；
In order to realize the selection of a certain frequency in a photonic band gap, a line defect is introduced to change the dielectric constant of an adjacent semiconductor dielectric material in a complete lattice in the direction of a periodic structure, and a point defect is realized by symmetrically changing the size of the etching radius of the semiconductor dielectric material, refer to fig. 3 and 4, wherein the radius of 2 point defects in third vicinity is increased in fig. 3, the radius of 2 point defects in third vicinity is reduced in fig. 4, the corresponding transmission spectrum can show that the defect structure can effectively select a defect state photon with a certain frequency from a photon forbidden band, the defect state photon with a certain frequency can pass through with low consumption while other frequencies are forbidden, therefore, the defect state photon can realize the stealth of a radar of a self, the photonic crystal can realize the confusion of a radar of an enemy radar without influencing the radar of the self radar, and the stealth of the self radar is realized.
Meanwhile, in order to improve the stealth effect of the radar (the incidence angles are different and the isotropy of the photonic crystal), the photonic crystal is expanded into two dimensions or three dimensions (one dimension: a periodic dielectric structure has a periodic structure in one direction and is uniform in the other two directions), (two dimensions: the periodic dielectric structure has a periodic structure in two directions and is uniform in the other two directions), and (three dimensions: the periodic dielectric structure has a periodic structure in three directions).
The above-mentioned embodiments are only for convenience of description, and are not intended to limit the present invention in any way, and those skilled in the art will understand that the technical features of the present invention can be modified or changed by other equivalent embodiments without departing from the scope of the present invention.
Claims (9)
1. The utility model provides a stealthy external member of radar based on metamaterial, it includes that the cover establishes the first stealthy external member on the radar vehicle and establishes the second camouflage external member on the radar, and first stealthy external member and second camouflage external member provide vehicle and radar at the stealthy of microwave, visible light and infrared band when guaranteeing that vehicle, radar can normally work, its characterized in that: the first stealth kit comprises a radar wave-absorbing base layer and a photonic crystal infrared stealth layer etched on the radar wave-absorbing base layer; the second camouflage kit comprises a photonic crystal infrared stealth layer and a radar wave photonic crystal stealth layer etched above the photonic crystal infrared stealth layer; the photonic crystal infrared stealth layer is a metamaterial with a periodic dielectric structure formed by etching two semiconductor dielectric materials and has a photonic band gap of visible light and infrared bands; the radar wave photonic crystal stealth layer is made of a metamaterial with a periodic dielectric structure formed by etching two semiconductor dielectric materials, and the radar wave photonic crystal stealth layer is provided with a photonic band gap of a radar wave band and can simultaneously select and pass the radar wave band with a certain frequency in the photonic band gap.
2. A metamaterial-based radar stealth kit in accordance with claim 1, wherein: the radar wave-absorbing base layer is prepared by coating wave-absorbing materials on non-woven fabrics by a coating method, and the wave-absorbing materials are composed of graphene, magnetic metal and conductive high polymer.
3. A metamaterial-based radar stealth kit in accordance with claim 2, wherein: the semiconductor dielectric material is selected from silicon, tellurium, selenium, germanium or a semiconductor compound, and the refractive index difference between the two dielectric materials is ensured.
4. A metamaterial-based radar stealth kit in accordance with claim 3, wherein: the periodic dielectric structure is one having a periodic structure in one direction and is uniform in the other two directions.
5. A metamaterial-based radar stealth kit according to claim 3, characterized in that: the periodic dielectric structure is a periodic structure in two directions and is uniform in the other direction.
6. A metamaterial-based radar stealth kit according to claim 3, characterized in that: the periodic dielectric structure has a periodic structure in three directions.
7. A metamaterial-based radar stealth kit according to any one of claims 1 to 6, characterized in that: the radar wave photonic crystal stealth layer realizes the selection of radar wave bands with certain frequency in a photonic band gap by introducing defects in the photonic crystal, wherein the defects comprise line defects and point defects.
8. A metamaterial-based radar stealth kit in accordance with claim 7, wherein: the line defects are realized by changing the dielectric constant of the adjacent semiconductor dielectric material in a complete lattice in the direction of the periodic structure.
9. A metamaterial-based radar stealth kit in accordance with claim 7, wherein: the point defect is realized by symmetrically changing the size of the etching radius of the semiconductor dielectric material.
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