阅读说明：本技术 电场调控单向金属-介质复合隐身器件及制作方法 (Electric field regulation and control one-way metal-medium composite stealth device and manufacturing method thereof ) 是由 赵乾 彭瑞光 孟永钢 周济 于 2020-06-24 设计创作，主要内容包括：本发明公开了一种电场调控单向金属-介质复合隐身器件及制作方法,隐身器件包括隐身器件主体和电场调控系统；隐身器件主体包括第一电介质板、第二电介质板和金属十字阵列；第一电介质板与第二电介质板交替排列构成层状堆叠结构；第一电介质板的两侧面上分别对称附着金属十字阵列；电场调控系统包括直流稳压电源、直流偏压线和直流电压控制器；第一电介质板的两侧面上的金属十字阵列通过直流偏压线分别与直流稳压电源的正极和负极相连；直流电压控制器用于控制直流稳压电源的输出电压以调节施加于第一电介质板的直流电场,实现对隐身器件工作频率的调谐。本发明可以实现对不同频段的电磁波的隐身,适用范围大且结构稳定性高。(The invention discloses an electric field regulation unidirectional metal-medium composite stealth device and a manufacturing method thereof, wherein the stealth device comprises a stealth device main body and an electric field regulation and control system; the cloaking device body comprises a first dielectric plate, a second dielectric plate and a metal cross array; the first dielectric plate and the second dielectric plate are alternately arranged to form a layered stacked structure; metal cross arrays are symmetrically attached to two side faces of the first dielectric plate respectively; the electric field regulation and control system comprises a direct current stabilized power supply, a direct current bias line and a direct current voltage controller; the metal cross arrays on the two side surfaces of the first dielectric plate are respectively connected with the anode and the cathode of the direct-current stabilized power supply through direct-current bias lines; the direct-current voltage controller is used for controlling the output voltage of the direct-current stabilized power supply so as to adjust the direct-current electric field applied to the first dielectric plate, and the tuning of the working frequency of the stealth device is realized. The invention can realize stealth of electromagnetic waves of different frequency bands, and has wide application range and high structural stability.)

1. An electric field regulation unidirectional metal-medium composite stealth device is characterized by comprising:

a cloaking device body comprising a first dielectric plate, a second dielectric plate, and a metal cross array; the dielectric constant of the first dielectric plate is higher than that of the second dielectric plate, the first dielectric plate and the second dielectric plate are alternately arranged to form a layered stacked structure, the layered stacked structure is a rhombic columnar body with a rhombic columnar space, the projection of the outer contour of the layered stacked structure on a projection plane in the vertical stacking direction is an outer rhombus, the projection of the contour of the rhombic columnar space on the projection plane in the vertical stacking direction is an inner rhombus, the center of the outer rhombus is coincident with the center of the inner rhombus, and a pair of opposite vertexes of the outer rhombus is coincident with a pair of opposite vertexes of the inner rhombus; the metal cross arrays are symmetrically attached to two side faces of the first dielectric plate respectively;

the electric field regulation and control system comprises a direct current stabilized power supply, a direct current bias line and a direct current voltage controller; the direct current stabilized power supply is used for applying stable direct current voltage to the first dielectric plate so as to enable the first dielectric plate to be in a stable direct current electric field; the metal cross arrays on the two side surfaces of the first dielectric plate are respectively connected with the anode and the cathode of the direct-current stabilized power supply through the direct-current bias lines; the direct-current voltage controller is used for controlling the output voltage of the direct-current stabilized power supply to adjust the direct-current electric field applied to the first dielectric plate, so that the dielectric constant of the first dielectric plate is changed, the frequency characteristic curve of the stealth device body is moved, and the tuning of the operating frequency of the stealth device is achieved.

2. The electric field regulating unidirectional metal-dielectric composite stealth device of claim 1, wherein the permittivity of said first dielectric plate varies with a variation in an electric field, and the value of the permittivity of said first dielectric is greater than 50.

3. The electric field regulated unidirectional metal-dielectric composite stealth device of claim 2, wherein said second dielectric plate has a permittivity in the range of 0.8-2.0.

4. The electric field controlled unidirectional metal-dielectric composite cloaking device as recited in claim 1, wherein when the cloaking device body is referenced to an x 'y' z 'coordinate system, one pair of opposing vertices of the outer rhombus are in an x' direction, the other pair of opposing vertices of the outer rhombus are in a y 'direction, and a centerline of the layered stacking structure is in a z' direction; the cloaking device body is symmetrical with the cloaking device body by a y axis at a portion located in a second quadrant of the x 'y' z 'coordinate system and a portion located in a first quadrant of the x' y 'z' coordinate system, the cloaking device body is symmetrical with the cloaking device body by a y axis at a portion located in a third quadrant of the x 'y' z 'coordinate system and a portion located in a fourth quadrant of the x' y 'z' coordinate system and a portion located in a second quadrant of the x 'y' z 'coordinate system and a portion located in a first quadrant of the x' y 'z' coordinate system; the metal cross array of the cloaking device body in the portion located in the first quadrant of the x ' y ' z ' coordinate system is specifically: the z-axis direction in the xyz coordinate system coincides with the z '-axis direction of the x' y 'z' coordinate system, the x-axis direction in the xyz coordinate system has an included angle θ with the x '-axis direction of the x' y 'z' coordinate system, the plurality of metal crosses in the metal cross array are arranged at intervals along the x-axis direction and the y-axis direction, and the two metal arms of the metal cross in the metal cross array are parallel to the x-axis direction and the y-axis direction respectively.

5. The electric field controlled unidirectional metal-dielectric composite stealth device according to claim 4, wherein the included angle θ satisfies the following formula:

wherein the content of the first and second substances,

beta is an included angle between the outer boundary of the stealth device main body and an x' axis;

alpha is the included angle between the inner boundary of the stealth device main body and the x' axis.

6. The electric field controlled unidirectional metal-dielectric composite cloaking device as claimed in claim 4, wherein the lengths of the two metal arms of the metal cross in the metal cross array along the x-axis and y-axis are different, and the distribution period of the metal cross array along the x-axis and y-axis is different.

7. The electric field controlled unidirectional metal-dielectric composite cloaking device as recited in claim 6, wherein the period lengths of the metal crosses in the metal cross array located in the first quadrant of the x ' y ' z ' coordinate system along the x-axis and y-axis directions of the xyz coordinate system are less than 1/5 of the wavelength of the electromagnetic wave corresponding to the operating frequency of the cloaking device.

8. The field regulated unidirectional metal-dielectric composite stealth device according to any one of claims 1-7, wherein said metal cross arrays on both sides of said first dielectric plate act as positive and negative poles, respectively, to provide said dc electric field to said first dielectric plate.

9. A method for manufacturing an electric field controlled unidirectional metal-dielectric composite stealth device, characterized in that the electric field controlled unidirectional metal-dielectric composite stealth device is the electric field controlled unidirectional metal-dielectric composite stealth device according to any one of claims 1 to 8, the method comprising the steps of:

machining the first dielectric plate and the second dielectric plate with required geometric dimensions;

processing the metal cross arrays and the direct-current bias lines on two side surfaces of the first dielectric plate, and respectively connecting the metal cross arrays on the two sides of the first dielectric plate to the positive electrode and the negative electrode of the direct-current stabilized voltage power supply through the direct-current bias lines;

and alternately arranging the first dielectric plate and the second dielectric plate attached with the metal cross array and the direct current bias line to form a layered stack structure.

Technical Field

The invention relates to the technical field of electromagnetic wave control, in particular to an electric field regulation and control unidirectional metal-dielectric composite stealth device and a manufacturing method thereof.

Background

The traditional stealth technology utilizes a wave-absorbing material to reduce reflection of radar waves to realize stealth, but in the case of more advanced detection technologies such as ground-air radar and multi-base radar, the stealth effect is generally difficult to keep continuously. Stealth techniques based on transform optics, which have been emerging in recent years, hold promise for addressing this challenge. By utilizing anisotropic electromagnetic parameters of specific spatial distribution, the transformation optical stealth device can control the propagation path of electromagnetic waves, so that the electromagnetic waves bypass a stealth area when being propagated in a stealth medium and return to the original incident direction when being emitted, so that the electromagnetic field distribution in the space is the same as that when no object exists in the area, and the real perfect stealth is realized.

However, stealth devices based on transform optics must have anisotropic complex electromagnetic parameters, which need to be achieved by means of artificially constructed electromagnetic metamaterials. The existing metamaterial utilizes electromagnetic resonance to realize specific equivalent electromagnetic parameters, has serious dispersion characteristics, and causes a stealth device to work in a fixed frequency band; the coupling among the electromagnetic resonances in different directions of the metamaterial makes the precise regulation and control of equivalent anisotropic electromagnetic parameters difficult, and a large amount of time and computing resources are consumed to optimally design the structure; furthermore, metamaterials often require the use of a supporting frame or a substrate to achieve a periodic spatial distribution of the electromagnetic resonance units, which easily causes assembly errors and reduces structural stability, limiting the range of applications of the cloaking device.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, one object of the present invention is to provide an electric field controlled unidirectional metal-dielectric composite stealth device, which can realize stealth of electromagnetic waves of different frequency bands, and has the advantages of wide application range, convenient control, simple and reasonable structure, convenient assembly and high structural stability.

According to the embodiment of the first aspect of the invention, the electric field regulation unidirectional metal-medium composite stealth device comprises:

a cloaking device body comprising a first dielectric plate, a second dielectric plate, and a metal cross array; the dielectric constant of the first dielectric plate is higher than that of the second dielectric plate, the first dielectric plate and the second dielectric plate are alternately arranged to form a layered stacked structure, the layered stacked structure is a rhombic columnar body with a rhombic columnar space, the projection of the outer contour of the layered stacked structure on a projection plane in the vertical stacking direction is an outer rhombus, the projection of the contour of the rhombic columnar space on the projection plane in the vertical stacking direction is an inner rhombus, the center of the outer rhombus is coincident with the center of the inner rhombus, and a pair of opposite vertexes of the outer rhombus is coincident with a pair of opposite vertexes of the inner rhombus; the metal cross arrays are symmetrically attached to two side faces of the first dielectric plate respectively;

the electric field regulation and control system comprises a direct current stabilized power supply, a direct current bias line and a direct current voltage controller; the direct current stabilized power supply is used for applying stable direct current voltage to the first dielectric plate so as to enable the first dielectric plate to be in a stable direct current electric field; the metal cross arrays on the two side surfaces of the first dielectric plate are respectively connected with the anode and the cathode of the direct-current stabilized power supply through the direct-current bias lines; the direct-current voltage controller is used for controlling the output voltage of the direct-current stabilized power supply to adjust the direct-current electric field applied to the first dielectric plate, so that the dielectric constant of the first dielectric plate is changed, the frequency characteristic curve of the stealth device body is moved, and the tuning of the operating frequency of the stealth device is achieved.

According to the electric field control one-way metal-dielectric composite stealth device of the embodiment of the first aspect of the present invention, the first dielectric plate and the second dielectric plate are alternately arranged to form a layered stack structure, two side surfaces of the first dielectric plate are respectively attached with an array of metal crosses, the metal crosses generate magnetic resonance in an alternating magnetic field, so that, the equivalent anisotropic permeability in the direction of the two metal arms of the metal cross can be realized by the magnetic resonance of the metal cross, the equivalent permittivity in the stacking direction is achieved by a layered stack structure of a first dielectric plate and a second dielectric plate, when the stealth device realizes the equivalent dielectric constant and the equivalent magnetic permeability of specific anisotropy required by a transformation optical theory in a certain specific frequency band, the stealth device can control the propagation path and phase of electromagnetic waves, so that an obstacle in the rhombic columnar space hides the electromagnetic waves incident in a single direction in a plane; the output voltage of the direct-current voltage-stabilized power supply is controlled through the direct-current voltage controller, the direct-current voltages on two sides of the first dielectric plate are adjusted, namely, the direct-current electric field where the first dielectric plate is located is adjusted, so that the dielectric constant of the first dielectric plate is changed, the resonance characteristic of the metal cross is changed, the equivalent permeability dispersion curve of the metal cross array is moved, the working frequency of the stealth device is tuned, and therefore stealth of electromagnetic waves of different frequency bands is achieved. In summary, the electric field regulation unidirectional metal-dielectric composite stealth device provided by the embodiment of the first aspect of the invention can realize stealth of electromagnetic waves of different frequency bands, and has the advantages of wide application range, convenience in control, simple and reasonable structure, convenience in assembly and high structural stability.

According to an embodiment of the first aspect of the present invention, the permittivity of the first dielectric plate varies with a variation of the electric field, and the value of the permittivity of the first dielectric is larger than 50.

According to a further embodiment of the first aspect of the present invention, the second dielectric plate has a permittivity in the range of 0.8 to 2.0.

According to one embodiment of the first aspect of the present invention, when the cloaking device body is referenced to an x 'y' z 'coordinate system, one pair of opposite vertices of the outer rhombus is in an x' axis direction, the other pair of opposite vertices of the outer rhombus is in a y 'axis direction, and a centerline of the layered stacking structure is in a z' axis direction; the cloaking device body is symmetrical with the cloaking device body by a y axis at a portion located in a second quadrant of the x 'y' z 'coordinate system and a portion located in a first quadrant of the x' y 'z' coordinate system, the cloaking device body is symmetrical with the cloaking device body by a y axis at a portion located in a third quadrant of the x 'y' z 'coordinate system and a portion located in a fourth quadrant of the x' y 'z' coordinate system and a portion located in a second quadrant of the x 'y' z 'coordinate system and a portion located in a first quadrant of the x' y 'z' coordinate system; the metal cross array of the cloaking device body in the portion located in the first quadrant of the x ' y ' z ' coordinate system is specifically: the z-axis direction in the xyz coordinate system coincides with the z '-axis direction of the x' y 'z' coordinate system, the x-axis direction in the xyz coordinate system has an included angle θ with the x '-axis direction of the x' y 'z' coordinate system, the plurality of metal crosses in the metal cross array are arranged at intervals along the x-axis direction and the y-axis direction, and the two metal arms of the metal cross in the metal cross array are parallel to the x-axis direction and the y-axis direction respectively.

According to a further embodiment of the first aspect of the present invention, the included angle θ satisfies the following formula:

wherein the content of the first and second substances,

beta is an included angle between the outer boundary of the stealth device main body and an x' axis;

alpha is the included angle between the inner boundary of the stealth device main body and the x' axis.

According to a further embodiment of the first aspect of the present invention, the two metal arms of the metal crosses in the metal cross array along the x-axis and the y-axis are different in length, and the distribution period of the metal cross array along the x-axis and the y-axis is different.

According to a still further embodiment of the first aspect of the present invention, the period lengths of the metal crosses in the array of metal crosses located in the first quadrant of the x ' y ' z ' coordinate system along the x-axis and y-axis directions of the xyz coordinate system are both less than 1/5 of the wavelength of the electromagnetic wave corresponding to the operating frequency of the cloaking device.

According to some embodiments of the first aspect of the present invention, the metal cross arrays on both sides of the first dielectric plate act as positive and negative electrodes, respectively, to provide the dc electric field to the first dielectric plate.

The invention also provides a manufacturing method of the electric field regulation unidirectional metal-medium composite stealth device.

According to the manufacturing method of the electric field control unidirectional metal-dielectric composite stealth device in the second aspect of the embodiment of the present invention, the electric field control unidirectional metal-dielectric composite stealth device is the electric field control unidirectional metal-dielectric composite stealth device in any one of the first aspect of the embodiments, and the manufacturing method includes the following steps:

machining the first dielectric plate and the second dielectric plate with required geometric dimensions;

processing the metal cross arrays and the direct-current bias lines on two side surfaces of the first dielectric plate, and respectively connecting the metal cross arrays on the two sides of the first dielectric plate to the positive electrode and the negative electrode of the direct-current stabilized voltage power supply through the direct-current bias lines;

and alternately arranging the first dielectric plate and the second dielectric plate attached with the metal cross array and the direct current bias line to form a layered stack structure.

According to the manufacturing method of the electric field control unidirectional metal-dielectric composite stealth device in the embodiment of the second aspect of the invention, a dielectric plate with a high dielectric constant is selected, a first dielectric plate with a required geometric dimension is machined, a dielectric plate with a low dielectric constant is selected, and a second dielectric plate with a required geometric dimension is machined; required metal cross arrays and direct current bias lines are processed on two sides of the first dielectric plate in modes of printed circuit boards, micro-processing or 3D printing and the like, the first dielectric plate and the second dielectric plate, to which the metal cross arrays and the direct current bias lines are attached, are alternately arranged to form a layered stacked structure, a stealth device body is obtained, one ends of a plurality of direct current bias lines are respectively connected with the metal cross arrays on the two sides of the first dielectric plate in a one-to-one correspondence mode, and the other ends of the plurality of direct current bias lines are respectively connected to the positive pole or the negative pole of the direct current stabilized voltage power supply. Therefore, the electric field regulation and control one-way metal-dielectric composite stealth device is simple to manufacture and convenient to assemble, the output voltage of the direct current stabilized voltage power supply is controlled through the direct current voltage controller, the direct current voltages on two sides of the first dielectric plate are adjusted, namely, the direct current electric field where the first dielectric plate is located is adjusted, the dielectric constant of the first dielectric plate is changed, the resonance characteristic of the metal cross is changed, the equivalent magnetic permeability dispersion curve of the metal cross array is moved, the working frequency of the stealth device is tuned, and therefore the stealth of the electromagnetic waves in different frequency bands is achieved.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural diagram of an electric field control unidirectional metal-dielectric composite stealth device according to an embodiment of the first aspect of the present invention.

Fig. 2 is an enlarged schematic view of a point a in fig. 1.

Fig. 3 is a schematic view illustrating the assembly of the first dielectric plate and the metal cross in the electric field control unidirectional metal-dielectric composite stealth device according to the embodiment of the first aspect of the present invention.

FIG. 4 is a diagram illustrating the anisotropic equivalent permeability μ achieved by the metal cross array of the electric field controlled unidirectional metal-dielectric composite stealth device according to the first embodiment of the present invention_x,eff，μ_y,effAnd equivalent dielectric constant_z,effIn which mu_x,effAnd mu_y,effHas a Lorentzian-type dispersion curve at the magnetic resonance frequency.

Fig. 5 is a diagram illustrating the stealth effect of the electric field-controlled uni-directional metal-dielectric composite stealth device according to the first embodiment of the present invention on the planar electromagnetic wave emitted by the planar electromagnetic wave emission source and incident in the x' direction in the plane.

Reference numerals:

stealth device 1000

Stealth device body 1

Layered stack 11

Rhombic columnar space 111 rhombic columnar body 112, first dielectric plate 113, and second dielectric plate 114

Metal cross array 12

Metal cross 121 metal arm 1211 metal-medium composite metamaterial unit 13

Electric field regulation and control system 2

DC voltage regulator 21 DC bias line 22 DC voltage controller 23

Planar electromagnetic wave emission source 3

Planar electromagnetic wave 4

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

The electric field controlled unidirectional metal-dielectric composite cloaking device 1000 according to the first embodiment of the present invention is described below with reference to fig. 1 to 5.

As shown in fig. 1 to 5, an electric field control unidirectional metal-dielectric composite stealth device 1000 according to an embodiment of the first aspect of the present invention includes a stealth device main body 1 and an electric field control system 2; the cloaking device body 1 includes a first dielectric plate 113, a second dielectric plate 114, and a metal cross array 12; the dielectric constant of the first dielectric plate 113 is higher than that of the second dielectric plate 114, the first dielectric plate 113 and the second dielectric plate 114 are alternately arranged to form the layered stacked structure 11, the layered stacked structure 11 is a rhombic columnar body 112 with a rhombic columnar space 111, the projection of the outer contour of the layered stacked structure 11 on a projection plane in the vertical stacking direction is an outer rhombus, the projection of the contour of the rhombic columnar space 111 on the projection plane in the vertical stacking direction is an inner rhombus, the center of the outer rhombus is coincident with the center of the inner rhombus, and a pair of opposite top points of the outer rhombus is coincident with a pair of opposite top points of the inner rhombus; the metal cross arrays 12 are symmetrically attached to two side surfaces of the first dielectric plate 113 respectively; the electric field regulation and control system 2 comprises a direct current stabilized voltage supply 21, a direct current bias line 22 and a direct current voltage controller 23; the dc regulated power supply 21 is configured to apply a stable dc voltage to the first dielectric plate 113, so that the first dielectric plate 113 is in a stable dc electric field; the metal cross arrays 12 on the two side surfaces of the first dielectric plate 113 are respectively connected with the anode and the cathode of a direct current stabilized power supply 21 through a direct current bias line 22; the dc voltage controller 23 is configured to control an output voltage of the dc voltage regulator 21 to adjust a dc electric field applied to the first dielectric plate 113, so as to change a dielectric constant of the first dielectric plate 113, shift a frequency characteristic curve of the stealth device main body 1, and tune an operating frequency of the stealth device 1000.

Specifically, the cloaking device body 1 includes a first dielectric plate 113, a second dielectric plate 114, and a metal cross array 12; the dielectric constant of the first dielectric plate 113 is higher than that of the second dielectric plate 114, the first dielectric plate 113 and the second dielectric plate 114 are alternately arranged to form the layered stacked structure 11, the layered stacked structure 11 is a rhombic columnar body 112 with a rhombic columnar space 111, the projection of the outer contour of the layered stacked structure 11 on a projection plane in the vertical stacking direction is an outer rhombus, the projection of the contour of the rhombic columnar space 111 on the projection plane in the vertical stacking direction is an inner rhombus, the center of the outer rhombus is coincident with the center of the inner rhombus, and a pair of opposite top points of the outer rhombus is coincident with a pair of opposite top points of the inner rhombus; the metal cross arrays 12 are symmetrically attached to both side surfaces of the first dielectric plate 113. It can be understood that the first dielectric plate 113 and the second dielectric plate 114 are alternately arranged to form the layered stack structure 11, and the metal cross arrays 12 are respectively attached to the two side surfaces of the first dielectric plate 113, so that the equivalent anisotropic magnetic permeability along the two metal arms 1211 of the metal cross 121 can be realized through the magnetic resonance of the metal cross 121, the equivalent permittivity along the stack direction can be realized through the layered stack structure 11 of the first dielectric plate 113 and the second dielectric plate 114, and the stealth device 1000 can meet the requirement of controlling the propagation path and the phase of the electromagnetic wave by transforming the optical theory, thereby realizing the stealth of the obstacles inside the rhombic columnar space 111; preferably, the permittivity of the first dielectric plate 113 is much higher than the permittivity of the second dielectric plate 114.

The electric field regulation and control system 2 comprises a direct current stabilized voltage supply 21, a direct current bias line 22 and a direct current voltage controller 23; the dc regulated power supply 21 is configured to apply a stable dc voltage to the first dielectric plate 113, so that the first dielectric plate 113 is in a stable dc electric field; the metal cross arrays 12 on the two side surfaces of the first dielectric plate 113 are respectively connected with the anode and the cathode of a direct current stabilized power supply 21 through a direct current bias line 22; the dc voltage controller 23 is configured to control an output voltage of the dc voltage regulator 21 to adjust a dc electric field applied to the first dielectric plate 113, so as to change a dielectric constant of the first dielectric plate 113, shift a frequency characteristic curve of the stealth device main body 1, and tune an operating frequency of the stealth device 1000. It can be understood that the metal cross arrays 12 on both sides of the first dielectric plate 113 are respectively connected together by the dc bias line 22 and connected to the positive electrode or the negative electrode of the dc regulated power supply 21, so as to apply a stable DC electric field to the first dielectric plate 113, by utilizing the characteristic that the permittivity of the first dielectric plate 113 itself changes with the change of the DC electric field, the output voltage of the DC stabilized power supply 21 is controlled by the DC voltage controller 23, the DC voltage on both sides of the first dielectric plate 113 is adjusted, namely, the dc electric field of the first dielectric plate 113 is adjusted, so as to change the permittivity of the first dielectric plate 113, and change the resonance characteristics of the metal cross 121, so that the equivalent permeability dispersion curve of the metal cross array 12 is shifted, the operating frequency of the cloaking device 1000 may be tuned to thereby achieve cloaking of electromagnetic waves of different frequency bands.

According to the electric field control one-way metal-dielectric composite stealth device 1000 of the embodiment of the first aspect of the present invention, the first dielectric plate 113 and the second dielectric plate 114 are alternately arranged to form the layered stack structure 11, the metal cross arrays 12 are respectively attached to the two side surfaces of the first dielectric plate 113, and the metal cross 121 generates magnetic resonance in the alternating magnetic field, so that the magnetic resonance of the metal cross 121 can achieve equivalent anisotropic permeability along the directions of the two metal arms 1211 of the metal cross 121, the equivalent permittivity along the stacking direction can be achieved by the layered stack structure 11 of the first dielectric plate 113 and the second dielectric plate 114, and when the stealth device 1000 achieves the equivalent permittivity and equivalent permeability of specific anisotropy required by the transform optical theory in a specific frequency band, the stealth device 1000 can control the requirements of the electromagnetic wave propagation path and phase, the obstacles in the rhombic columnar space 111 can hide electromagnetic waves incident in a single direction in a plane; the output voltage of the dc regulated power supply 21 is controlled by the dc voltage controller 23, and the dc voltages at the two sides of the first dielectric plate 113 are adjusted, that is, the dc electric field where the first dielectric plate 113 is located is adjusted, so as to change the dielectric constant of the first dielectric plate 113, change the resonance characteristic of the metal cross 121, move the equivalent permeability dispersion curve of the metal cross array 12, and tune the operating frequency of the stealth device 1000, thereby realizing the stealth of the electromagnetic waves of different frequency bands. In summary, the electric field regulation unidirectional metal-dielectric composite stealth device 1000 according to the embodiment of the first aspect of the present invention can realize stealth of electromagnetic waves in different frequency bands, and has the advantages of wide application range, convenient control, simple and reasonable structure, convenient assembly, and high structural stability.

According to an embodiment of the first aspect of the present invention, the permittivity of the first dielectric plate 113 varies with a variation of the electric field, and the value of the permittivity of the first dielectric is larger than 50. It is understood that, since the permittivity of the high permittivity dielectric plate varies significantly with the variation of the electric field, the first dielectric plate 113 should be a high permittivity dielectric plate having a permittivity variation coefficient with the variation of the applied electric field, so that the permittivity of the first dielectric plate 113 can be significantly adjusted by adjusting the electric field, for example, the first dielectric plate 113 may be a ferroelectric ceramic material having a permittivity greater than 50.

According to a further embodiment of the first aspect of the present invention, the second dielectric plate 114 has a permittivity in the range of 0.8 to 2.0. Specifically, the dielectric constant of the second dielectric plate 114 may be 0.8, 1.0, or 1.2, and the dielectric plate with a low dielectric constant, such as balsa wood or fluoropolymer foam, having a dielectric constant much lower than that of the first dielectric plate 113, may be used for the second dielectric plate 114, so as to effectively reduce interference with incident electromagnetic waves.

According to an embodiment of the first aspect of the present invention, when the cloaking device body 1 is referenced to the x 'y' z 'coordinate system, one pair of two opposite vertices of the outer rhombus are in the x' axis direction, the other pair of two opposite vertices of the outer rhombus are in the y 'axis direction, and the central line of the layered stacking structure 11 is in the z' axis direction; the part of the cloaking device body 1 located in the second quadrant of the x 'y' z 'coordinate system is symmetrical to the part of the cloaking device body 1 located in the first quadrant of the x' y 'z' coordinate system by the y axis, the part of the cloaking device body 1 located in the third quadrant of the x 'y' z 'coordinate system and the part of the cloaking device body 1 located in the fourth quadrant of the x' y 'z' coordinate system are symmetrical to the part of the cloaking device body 1 located in the second quadrant of the x 'y' z 'coordinate system and the part of the cloaking device body 1 located in the first quadrant of the x' y 'z' coordinate system by the x axis; the metal cross array 12 of the cloaking device body 1 in the portion located in the first quadrant of the x ' y ' z ' coordinate system is specifically: the z-axis direction in the xyz coordinate system coincides with the z '-axis direction of the x' y 'z' coordinate system, the x-axis direction in the xyz coordinate system has an angle θ with the x '-axis direction of the x' y 'z' coordinate system, the plurality of metal crosses 121 in the metal cross array 12 are arranged at intervals along the x-axis direction and the y-axis direction, and the two metal arms 1211 of the metal crosses 121 in the metal cross array 12 are parallel to the x-axis direction and the y-axis direction, respectively. Specifically, when the cloaking device body 1 is referenced to an x ' y ' z ' coordinate system, one pair of opposite vertices of the outer rhombus is located in the x ' axis direction, the other pair of opposite vertices of the outer rhombus is located in the y ' axis direction, one pair of opposite vertices of the inner rhombus is located in the x ' axis and coincides with one pair of opposite vertices of the outer rhombus, the center line of the layered stacking structure 11 is located in the z ' axis direction, each quadrant comprises one triangular metal cross array 12 and the layered stacking structure 11, and the metal crosses 121 are arranged in a spaced manner along the x axis direction and the y axis direction.

According to a further embodiment of the first aspect of the present invention, the included angle θ satisfies the following equation:

wherein the content of the first and second substances,

beta is an included angle between the outer boundary of the stealth device main body 1 and the x' axis;

alpha is the included angle between the inner boundary of the stealth device body 1 and the x' axis.

It can be understood that, according to the principle of transforming optics, after determining the included angle α between the inner boundary of the cloaking device body 1 and the x ' axis and the included angle β between the outer boundary of the cloaking device body 1 and the x ' axis, the cloaking device body 1 needs to have specific anisotropic dielectric constant and magnetic permeability, for example, the first quadrant of the x ' y ' z ' coordinate system, the cloaking device body 1 in the first quadrant needs anisotropic electromagnetic parameter, namely the magnetic permeability mu in the x-axis direction_xMagnetic permeability mu in y-axis direction_yAnd dielectric constant in z-axis direction_zWherein the x axis and the x 'axis form an included angle theta, the z axis is coincident with the z' axis, and theta, β and α satisfy the relation:

according to lenz's law and electromagnetic induction law, an alternating current is generated in the metal cross 121 in the alternating electromagnetic field, so that magnetic resonance can be generated in two directions perpendicular to the metal arms 1211 of the metal cross 121, and therefore, the magnetic permeability μ in the x-axis direction is realized by the metal arms 1211 in the metal cross array 12 parallel to the y-axis direction_xThe permeability μ in the y-axis direction is realized by a metal arm 1211 parallel to the x-axis direction in the metal cross array 12_yAnd the dielectric constant in the z-axis direction is realized by the layered stacked structure 11 of the first dielectric plate 113 and the second dielectric plate 114_z。

It should be noted that each pair of the metal crosses 121 and the first dielectric plate 113 and the second dielectric plate 114 in the rectangular parallelepiped region thereof constitute one metal-dielectric composite metamaterial unit 13, as shown in fig. 2, the equivalent permeability of one metal-dielectric composite metamaterial unit 13 is a function of the frequency of the incident electromagnetic wave, and the equivalent permittivity hardly changes with the frequency change in the operating band. By utilizing the magnetic resonance characteristic of the metal cross 121, the geometric parameters (the length of the metal arm 1211, the line width of the metal arm 1211, the period length of the metal cross array 12 and the like) of the metal cross array 12 are adjusted, so that the equivalent magnetic permeability and the equivalent dielectric constant of the metal-dielectric composite metamaterial unit 13 in several different directions simultaneously reach values required by a conversion optical theory under a certain working frequency band, and at the moment, the electromagnetic waves in the stealth medium bypass the stealth area to be emitted, thereby realizing the stealth of the electromagnetic waves. In the alternating electromagnetic field, an alternating current is generated inside the metal cross 121, which is equivalent to an RLC series resonant circuit, and the equivalent inductance L and the equivalent capacitance C of the series resonant circuit are both related to the dielectric constant of the first dielectric plate 113, so that the equivalent inductance and the equivalent capacitance of the RLC series resonant circuit can be changed by changing the dielectric constant of the first dielectric plate 113 by adjusting the electric field, thereby changing the frequency response characteristic of the RLC series resonant circuit to the incident electromagnetic wave and achieving the purpose of tuning the working frequency of the RLC series resonant circuit.

Note that, as shown in fig. 4, the anisotropic equivalent permeability μ achieved by the metal cross array 12_x,effAnd mu_y,effHaving a Lorentz-type dispersion curve at the magnetic resonance frequency, the equivalent permittivity realized by the layered stack structure 11 of the first dielectric plate 113 and the second dielectric plate 114_z,effThe metamaterial has a constant value which is almost non-dispersive, can realize equivalent magnetic permeability and equivalent dielectric constant in a certain range, does not have coupling among electromagnetic resonances in different directions of the metamaterial structure, and can realize accurate design of equivalent electromagnetic parameters.

The following specific examples describe the magnetic permeability μ in the x-axis direction and the included angle θ between the x-axis and the x ' -axis when the included angle α between the inner boundary of the cloaking device body 1 and the x ' -axis and the included angle β between the outer boundary of the cloaking device body 1 and the x ' -axis are changed_xMagnetic permeability mu in y-axis direction_yAnd dielectric constant in z-axis direction_z。

When the angle β is 60 degrees and the angle α is 30 degrees, the electromagnetic parameters of the stealth device main body 1 in the first quadrant, which need to be anisotropic, are that the included angle theta between the x axis and the x' axis is 39.6 degrees and the magnetic permeability mu in the direction of the x axis_x2.2154 magnetic field in y-axis directionConductivity mu_y0.4514, dielectric constant in z-axis direction_zIt was 1.5000.

When the angle β is 60 degrees and the angle α is 45 degrees, the electromagnetic parameters of the stealth device main body 1 in the first quadrant, which need to be anisotropic, are that the included angle theta between the x axis and the x' axis is 47.6 degrees and the magnetic permeability mu in the direction of the x axis is 47.6 degrees_x4.9528, magnetic permeability μ in the y-axis direction_y0.2019, dielectric constant in z-axis direction_zIs 2.3660.

When the angle β is 45 degrees and the angle α is 30 degrees, the electromagnetic parameters of the stealth device body 1 in the first quadrant which need to be anisotropic are that the included angle theta between the x axis and the x' axis is 28.9 degrees, and the magnetic permeability mu in the direction of the x axis_x3.2717, magnetic permeability μ in the y-axis direction_y0.3507, dielectric constant in z-axis direction_zIs 2.3660.

According to a further embodiment of the first aspect of the present invention, the two metal arms 1211 of the metal crosses 121 in the metal cross array 12 along the x-axis and the y-axis are different in length, and the distribution period of the metal cross array 12 along the x-axis and the y-axis is different. Specifically, as shown in fig. 2 and 3, the metal arm 1211 of the metal cross 121 along the x-axis has a length L_xThe length of the metal arm 1211 of the metal cross 121 along the y-axis is L_yThe distribution period of the metal cross array 12 along the x-axis direction is the length P of the metal-dielectric composite metamaterial unit 13 along the x-axis direction_xThe distribution period of the metal cross array 12 along the y-axis direction is the length P of the metal-medium composite metamaterial unit 13 along the y-axis direction_y。

According to a still further embodiment of the first aspect of the present invention, the period lengths of the metal crosses 121 in the metal cross array 12 located in the first quadrant of the x ' y ' z ' coordinate system along the x-axis and y-axis directions of the xyz coordinate system are both smaller than 1/5 of the wavelength of the electromagnetic wave corresponding to the operating frequency of the cloaking device 1000. It will be appreciated that the period (i.e., period length) P of the distribution of the metal cross array 12 along the x-axis direction_xAnd the distribution period P of the metal cross array 12 along the y-axis direction _y1/5 each smaller than the wavelength of the electromagnetic wave corresponding to the operating frequency of the stealth device 1000, that is, the length P of the metal-dielectric composite metamaterial unit 13 along the x-axis direction_xAnd the length P of the metal-dielectric composite metamaterial unit 13 along the y-axis direction_yThe wavelengths of the electromagnetic waves are different and smaller than 1/5 of the electromagnetic waves corresponding to the working frequency of the cloaking device 1000, so that the equivalent medium theoretical requirement of the metamaterial can be met, the metal-medium composite metamaterial unit 13 can be equivalent to a uniform medium, the electromagnetic characteristics of the metal-medium composite metamaterial unit are described by equivalent magnetic permeability and equivalent dielectric constant, and therefore the interference of the metal cross 121 on the incident electromagnetic waves can be effectively reduced.

It should be noted that, by keeping the geometric size and the array period of the metal cross array 12 and the thicknesses of the first dielectric plate 113 and the second dielectric plate 114 unchanged, the area of the rhombic columnar space 111 and the rhombic columnar body 112 of the stealth device body 1 is enlarged in an equal ratio, or the number of periods of the metal-dielectric composite metamaterial unit 13 in the z-axis direction of the stealth device body 1 is increased, so that the space of the rhombic columnar space 111 (i.e., the stealth region) can be enlarged, and the stealth of a large-sized obstacle can be realized.

According to some embodiments of the first aspect of the present invention, the metal cross arrays 12 on both sides of the first dielectric plate 113 act as positive and negative electrodes, respectively, to provide a dc electric field to the first dielectric plate 113. It can be understood that the metal cross arrays 12 on both sides of the first dielectric plate 113 are connected together by the dc bias line 22 and connected to the positive electrode and the negative electrode of the dc regulated power supply 21, respectively, to apply a stable dc electric field to the first dielectric plate 113, and since the first dielectric plate 113 has a characteristic that its permittivity changes with the change of the dc electric field, the output voltage of the dc regulated power supply 21 is controlled by the dc voltage controller 23, so that the metal cross arrays 12 on both sides of the first dielectric plate 113 can adjust the dc voltage on both sides of the first dielectric plate 113, that is, adjust the dc electric field of the first dielectric plate 113, thereby changing the permittivity of the first dielectric plate 113.

The second aspect of the present invention further provides a method for manufacturing the electric field controlled unidirectional metal-dielectric composite stealth device 1000.

According to the manufacturing method of the electric field control unidirectional metal-dielectric composite stealth device 1000 in the second aspect of the present invention, the electric field control unidirectional metal-dielectric composite stealth device 1000 is the electric field control unidirectional metal-dielectric composite stealth device 1000 in any one of the first aspect of the present invention, and the manufacturing method includes the following steps:

machining a first dielectric plate 113 and a second dielectric plate 114 with required geometric dimensions;

processing metal cross arrays 12 and a direct current bias line 22 on two side surfaces of the first dielectric plate 113, and respectively connecting the metal cross arrays 12 on the two sides of the first dielectric plate 113 to the anode and the cathode of a direct current stabilized power supply 21 through the direct current bias line 22;

the first dielectric plate 113 to which the metal cross array 12 and the dc bias line 22 are attached and the second dielectric plate 114 are alternately arranged to constitute the layered stack structure 11.

According to the method for manufacturing the electric field control unidirectional metal-dielectric composite stealth device 1000 according to the embodiment of the second aspect of the present invention, a dielectric plate with a high dielectric constant is selected, the first dielectric plate 113 with a desired geometric dimension is machined, a dielectric plate with a low dielectric constant is selected, and the second dielectric plate 114 with a desired geometric dimension is machined; the method comprises the steps of processing required metal cross arrays 12 and direct current bias lines 22 on two sides of a first dielectric plate 113 through printed circuit boards, micromachining or 3D printing and the like, alternately arranging the first dielectric plate 113 and a second dielectric plate 114, to which the metal cross arrays 12 and the direct current bias lines 22 are attached, to form a layered stacked structure 11, and obtaining the stealth device body 1, wherein one ends of a plurality of direct current bias lines 22 are respectively connected with the metal cross arrays 12 on two sides of the first dielectric plate 113 in a one-to-one correspondence mode, and the other ends of the plurality of direct current bias lines are respectively connected to the positive electrode or the negative electrode of a direct current stabilized voltage power supply 21. Therefore, the electric field regulation and control one-way metal-dielectric composite stealth device 1000 is simple to manufacture and convenient to assemble, the output voltage of the direct current stabilized voltage power supply 21 is controlled through the direct current voltage controller 23, the direct current voltage on the two sides of the first dielectric plate 113 is adjusted, namely, the electric direct current field where the first dielectric plate 113 is located is adjusted, so that the dielectric constant of the first dielectric plate 113 is changed, the resonance characteristic of the metal cross 121 is changed, the equivalent permeability dispersion curve of the metal cross array 12 is moved, the working frequency of the stealth device 1000 can be tuned, and therefore the stealth of the electromagnetic waves in different frequency bands is achieved.

The following describes the electric field control unidirectional metal-dielectric composite stealth device 1000 according to the first embodiment of the present invention. Firstly, a dielectric plate with high dielectric constant is selected, a first dielectric plate 113 with required geometric dimension is machined by a machining mode, a dielectric plate with low dielectric constant is selected, and a second dielectric plate 114 with required geometric dimension is machined by a machining mode; the method comprises the steps of processing required metal cross arrays 12 and direct current bias lines 22 on two sides of a first dielectric plate 113 through printed circuit boards, micromachining or 3D printing and the like, alternately arranging the first dielectric plate 113 and a second dielectric plate 114, to which the metal cross arrays 12 and the direct current bias lines 22 are attached, to form a layered stacked structure 11, and obtaining the stealth device body 1, wherein one end of each direct current bias line 22 is connected with the metal cross arrays 12 on the two sides of the first dielectric plate 113, and the other end of each direct current bias line is connected to a positive electrode and a negative electrode of a direct current stabilized voltage power supply 21. In actual work, an obstacle is placed in the rhombic columnar space 111 of the electric field control one-way metal-dielectric composite stealth device 1000, for a planar electromagnetic wave 4 emitted by the planar electromagnetic wave emission source 3 and incident in the x' direction in a plane, the stealth effect of the electric field control one-way metal-dielectric composite stealth device 1000 is as shown in fig. 5, the stealth device 1000 can control the equipotential surface of the emergent electromagnetic wave to be still planar and the emergent direction of the emergent electromagnetic wave to be consistent with the incident direction of the incident electromagnetic wave, and therefore electromagnetic wave stealth is achieved.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like are intended to mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.