CN102480025B - Feed-forward type radar antenna - Google Patents

Abstract

Translated fromChinese

本发明涉及一种前馈式雷达天线，所述天线包括馈源和超材料面板，所述天线还包括紧贴于所述超材料面板一侧的反射板，所述超材料面板包括多个具有折射率相同分布的多个核心层，所述每一核心层包括多个超材料单元，所述超材料单元包括单元基材以及人造微结构，所述超材料面板的每一核心层的折射率以其中心为圆心呈圆形分布，且随着半径的增加折射率逐渐减小，且半径相同处的折射率相同。本发明一种前馈式雷达天线通过设计超材料面板内部的金属微结构的形状，排布方式以改变超材料面板的折射率分布规律，并采用平板超材料，节约了天线的空间，改进了电磁波大角度入射的偏折问题，提高了能量辐射的效率；同时也提高了天线的前后比，使天线的方向性更好。

The invention relates to a feed-forward radar antenna, the antenna includes a feed source and a metamaterial panel, the antenna also includes a reflector close to one side of the metamaterial panel, and the metamaterial panel includes a plurality of A plurality of core layers with the same distribution of refractive index, each core layer includes a plurality of metamaterial units, the metamaterial units include unit substrates and artificial microstructures, the refractive index of each core layer of the metamaterial panel The distribution is circular with its center as the center, and the refractive index gradually decreases with the increase of the radius, and the refractive index at the same radius is the same. A feed-forward radar antenna of the present invention changes the distribution law of the refractive index of the metamaterial panel by designing the shape and arrangement of the metal microstructure inside the metamaterial panel, and adopts a flat metamaterial, which saves the space of the antenna and improves the The deflection problem of electromagnetic waves incident at a large angle improves the efficiency of energy radiation; at the same time, it also improves the front-to-back ratio of the antenna, making the antenna more directional.

Description

A kind of feed-forward type radar antenna

Technical field

The present invention relates to the radar antenna field, more particularly, relate to a kind of feed-forward type radar antenna that uses super material.

Background technology

As shown in Figure 1, the feed forward type parabolic antenna comprises feed 1,primary reflection surface 2 and support 3, described feed 1 is installed on the focus place ofprimary reflection surface 2, and the actinal surface of feed 1 is relative with the actinal surface ofprimary reflection surface 2, is concentrated by the electromagnetic wave ofprimary reflection surface 2 reflections and injects in the feed.The advantage of feed forward type parabolic antenna be feed to aerial electromagnetic block little, simple in structure, cost is low, Installation and Debugging are easy, but bigbore feed forward type parabolic antenna has following shortcoming: Installation and Debugging high frequency head is inconvenient, and tuner is positioned at the parabolic focus place, sunlight sometimes is focused onto on the tuner, the temperature of tuner is raise, reduced the signal to noise ratio of signal, also there is certain impact in reliability and life-span of tuner.

Moreover, the method for usually utilizing die casting and molding or adopting Digit Control Machine Tool to process in order to make the parabolic reflector face.The technological process of first method comprises: make parabolic mould, casting parabola and carry out the installation of paraboloidal reflector ground.The technique more complicated, cost is high, and paraboloidal shape will relatively accurately could realize the direction propagation of radar antenna, so also higher to the requirement of machining accuracy.Second method adopts large-size numerical control machine to carry out paraboloidal processing, by edit routine, and path that cutter is walked in the control Digit Control Machine Tool, thus cut out required parabolic shape.This method cutting is very accurate, but makes relatively difficulty of this large-size numerical control machine, and cost compare is high.

Summary of the invention

The object of the invention is to solve the problem that prior art is made the parabolic reflector face, feed-forward type radar antenna is provided, and this antenna has adopted dull and stereotyped super material, the space of having saved antenna, improve the deviation problem of electromagnetic wave wide-angle incident, improved the efficient of energy emission; Also improve simultaneously the front and back ratio of antenna, made the directivity of antenna better, also solved the difficulty of avoiding making high-precision parabolic reflector face simultaneously.

In order to achieve the above object, the following technical scheme of the present invention's employing:

A kind of feed-forward type radar antenna, described antenna comprises: feed is used for radiated electromagnetic wave; Super material panel, the electromagnetic wave that is used for described feed is given off is converted into plane electromagnetic wave from the sphere electromagnetic wave, described antenna also comprises the reflecting plate of being close to described super material panel one side, be used for reflection of electromagnetic wave converged to super material panel and reflect and to the distant place radiation, described super material panel comprises a plurality of a plurality of core layers with refractive index same distribution, described each core layer comprises a plurality of super material cell, described super material cell comprises unit base material and artificial micro-structural, the rounded distribution take its center as the center of circle of the refractive index of each core layer of described super material panel, and along with the increase refractive index of radius reduces gradually, and the refractive index that radius exists together mutually is identical.

Further, described super material cell also comprises the first packed layer, described artificial micro-structural between described unit base material and the first packed layer, the material of filling in described the first packed layer comprise air, artificial micro-structural and with the medium of described unit base material same material.

Further, described super material panel also comprises a plurality of graded beddings that are distributed in described core layer one side, described each graded bedding include sheet substrate layer, sheet the second packed layer and be arranged on air layer between described substrate layer and the packed layer.

The medium of filling in described the second packed layer further, comprise air and with the medium of described substrate layer same material.

Further, the refractive index of each core layer of described super material panel take its center as the center of circle along with Changing Pattern such as the following formula of radius r:

$n\left(r\right)=n_{\max }-\frac{\sqrt{{\mathrm{<figure-callout\; label="ss"\; filenames="HDA0000078463300000011.png"\; state="\{\{state\}\}">ss</figure-callout>}}^2+r^2}-\mathrm{ss}}{2d};$

N in the formula_MaxRepresent the largest refractive index value in described each core layer, d represents the gross thickness of all core layers, and ss represents described feed to the distance of the core layer of the most close feed position, the described a plurality of core layer inside radius r of n (r) expression place refractive index value.

Further, the refractive index in each graded bedding of described super material panel is equally distributed, and Changing Pattern such as the following formula of refraction index profile between a plurality of graded bedding:

$n_i={\left(\frac{n_{\max }+n_{\min }}{2}\right)}^{\frac{i}{m}},$i＝1、2、3、...、m，

N wherein_iThe refractive index value that represents i layer graded bedding, m represents the number of plies of graded bedding, n_MinRepresent the minimum refractive index value in described each core layer, n_MaxRepresent the largest refractive index value in described each core layer, wherein m layer graded bedding and core layer are close, and along with diminishing gradually away from core layer of m value, the ground floor graded bedding is the outermost layer graded bedding.

Further, described artificial micro-structural is for to form planar structure or the stereochemical structure that electromagnetic field is had response by at least one one metal wire, and described wire is copper wire or filamentary silver.

Further, described wire is attached on the described unit base material by etching, plating, brill quarter, photoetching, electronics is carved or ion is carved method.

Further, described artificial micro-structural for the shape of deriving of " worker " font, " worker " font, flakes or alabastrine derive shape any one.

Further, described first substrate layer and second substrate layer make by ceramic material, epoxy resin, polytetrafluoroethylene, FR-4 composite material or F4B composite material.

The present invention is with respect to prior art, have following beneficial effect: a kind of feed-forward type radar antenna of the present invention is by the shape of the metal micro structure of the super material panel of design inside, arrangement mode is to change the refraction index profile rule of super material panel, and adopted dull and stereotyped super material, saved the space of antenna, improve the deviation problem of electromagnetic wave wide-angle incident, improved the efficient of energy emission; Also improved simultaneously the front and back ratio of antenna, made the directivity of antenna better.

Description of drawings

Fig. 1 is the structural representation of forward-feed type parabolic antenna in the prior art;

Fig. 2 is the structural representation of a kind of feed-forward type radar antenna of the present invention;

Fig. 3 is the structural representation of super material panel of the present invention;

Fig. 4 is the structural representation of a plurality of core layers of super material of the present invention;

Fig. 5 is the structural representation of super material cell of the present invention;

Fig. 6 is the structural representation of super material graded bedding of the present invention;

Fig. 7 is the artificial micro-structural schematic diagram of arranging in the core layer of the present invention;

Fig. 8 is core layer variations in refractive index schematic diagram of the present invention;

Fig. 9 is core layer variations in refractive index schematic diagram of the present invention.

Embodiment

Below in conjunction with embodiment and accompanying drawing, the present invention is described in further detail, but embodiments of the present invention are not limited to this.

Fig. 2 is the structural representation of feed-forward type radar antenna of the present invention, this antenna comprises feed 10, super material panel 20 and reflecting plate 30, described feed 10 and expelling plate 30 lay respectively at the both sides of described super material panel 20, and reflecting plate 30 is close to super material panel 20 and is linked to each other.

Usually the electromagnetic wave from feed 10 radiation is the sphere electromagnetic wave, but the electromagnetic far field of sphere directional performance is bad, for remote signal transmission take the sphere electromagnetic wave as carrier significant limitation is arranged, and decay is fast, the present invention is by having the super material panel 20 of electromagnetic wave aggregation feature in feed 10 transmission directions design one, should super material panel 20 most of electromagnetic wave that feed 10 radiates be converted to plane electromagnetic wave from the sphere electromagnetic wave, and again converge and radiate by super material panel 20 refractions through reflecting plate 30 reflections at the electromagnetic wave by super material panel 20, so that the directivity of radar antenna is better, the antenna main lobe energy density is higher, energy is larger, and then the signal transmission distance take this plane electromagnetic wave as carrier is farther.

Fig. 3 is the structural representation of super material panel 20 shown in Figure 2, a plurality of gradedbeddings 220 that super material panel 20 comprises a plurality ofcore layers 210 and is distributed in close feed one side, eachcore layer 210 forms by a plurality of super material cell, described super material cell comprise the first packedlayer 213 ofunit base material 211, sheet and be arranged on describedunit base material 211 and the first packedlayer 213 between a plurality of artificial micro-structural 212, such as Fig. 4 and as shown in Figure 5.The material of described the first packedlayer 213 interior fillings can be air, artificial micro-structural and with the medium of described unit base material same material, such as, when the equivalent refractive index in the described super material cell of needs becomes large, the medium that can have larger refractive index in the first packedlayer 213 interior filling metal micro structures or filling; When the equivalent refractive index in the described super material cell of needs diminishes, can or not fill any medium at the first packedlayer 213 interior filling air dielectrics.A plurality of supermaterial core layers 210 in the super material panel 20 are stacked, and equidistantly arrange the ground assembling between eachcore layer 210, or in twos between the lamella direct forward and backward surface link into an integrated entity bondingly.During implementation, the distance between the number of super material core layer and each core layer can design according to demand.Each supermaterial core layer 210 is formed by a plurality of super material cell arrays, and whole supermaterial core layer 210 can be regarded as by a plurality of super material cell and forms along X, Y, three direction array arrangements of Z.

A plurality ofcore layers 210 of described super material panel 20 namely realize being converted to plane electromagnetic wave from the sphere electromagnetic wave that described feed 10 gives off by changing its inner refraction index profile to realize by the electromagnetic wave equiphase radiation behind the described super material panel 20.The refraction index profile of each supermaterial core layer 210 is all identical among the present invention, only the refraction index profile rule of a supermaterial core layer 210 is described in detail here.By to the topological pattern of artificial micro-structural 212, physical dimension with and the design that distributes atunit base material 211 and the first packedlayer 213, the refraction index profile of thecore layer 210 in the middle of making satisfies following rule: the refraction index profile of every onedeck core layer 210 is all identical, each core layer comprise one take the center ofcore layer 210 the circular face territory as the center of circle, the refractive index of circle centre position is maximum n in the described circular face territory_MaxAnd along with the increase of radius reduces gradually, the refractive index at same radius place is identical, as shown in Figure 9, provides n_Max～n_MinVariations in refractive index figure, but should know that variations in refractive index of the present invention is not as limit.Purpose of design of the present invention is: when making electromagnetic wave through each supermaterial core layer 210, the electromagnetic wave deflection angle is changed and final parallel radiation gradually.By formula S in θ=q Δ n, wherein θ is that the electromagnetic angle of required deviation, Δ n are front and back variations in refractive index differences, and q can determine the desired parameters value and reach purpose of design of the present invention for the thickness of super material function layer and by Computer Simulation.

Fig. 8 is the O-O ' view of super material core layer refractive index profile shown in Figure 9.As common practise we as can be known, electromagnetic refractive index with

Proportional, wherein μ is magnetic permeability, ε is dielectric constant, when a branch of electromagnetic wave propagates into another medium by a kind of medium, electromagnetic wave can reflect, when the refraction index profile of material inside is non-homogeneous, electromagnetic wave will be to the larger position deviation of refractive index ratio, therefore, the refractive index that designs super material panel 20inner core layer 210 each points makes it satisfy above-mentioned variations in refractive index rule, need to prove, because in fact super material cell is a cube but not a point, therefore above-mentioned circular face territory is approximate description, and the identical or essentially identical super material cell of actual refractive index distributes at a zigzag circumference.When being similar to computer with the smoothed curve such as the square pixels point-rendering is circular, oval, its specific design carries out the programming mode (for example OpenGL) of described point, curve is shown as smoothly when pixel is very little with respect to curve, and curve shows sawtooth when pixel is larger with respect to curve.

Realize the variation of Fig. 8 and refractive index shown in Figure 9 for eachcore layer 210 that makes super material panel 20, through theoretical and actual proof, can to the topological structure of described artificial micro-structural 212, physical dimension with and the design that distributes atunit base material 211 and the first packedlayer 213,unit base material 211 adopts dielectric insulation material to make, can be ceramic material, macromolecular material, ferroelectric material, ferrite material, ferromagnetic material etc., macromolecular material for example can be, epoxy resin or polytetrafluoroethylene.Artificial micro-structural 212 is for to be attached to the metal wire that response can be arranged electromagnetic wave on theunit base material 211 with certain geometry, metal wire can be that section is the copper cash of cylindric or flat, silver line etc., the general copper that adopts, because copper wire is relatively cheap, certainly the section of metal wire also can be other shapes, metal wire is by etching, electroplate, bore and carve, photoetching, electronics carve or ion quarter etc. technique be attached on theunit base material 211, described the first packedlayer 213 can be filled the medium of different materials, can the material identical withunit base material 211, it also can be artificial micro-structural, it can also be air, described eachcore layer 210 is comprised of a plurality of super material cell, whenever super material cell all has an artificial micro-structural, each super material cell can produce response to the electromagnetic wave that passes through wherein, thereby affect electromagnetic wave transmission therein, the size of each super material cell depends on the electromagnetic wave of needs response, be generally required response electromagnetic wavelength 1/10th, can not be regarded as in the space continuously otherwise comprise being arranged in that the super material cell of artificial micro-structural 212 forms in the space.

In the selected situation ofunit base material 211, shape, size and the spatial distribution onunit base material 211 thereof by adjusting artificial micro-structural 212 and fill the medium of different refractivities at the first packedlayer 213 can be adjusted everywhere effective dielectric constant and equivalent permeability and then the super material of change equivalent refractive index everywhere on the super material.When artificial micro-structural 212 adopted identical geometry, the size of the artificial micro-structural in somewhere was larger, and the effective dielectric constant that then should locate is larger, and refractive index is also larger.

The pattern of the artificial micro-structural 212 that present embodiment adopts is the I-shaped pattern of deriving, as shown in Figure 7, the size of the artificial micro-structural 212 of flakes therefrom diminishes around the mind-set gradually, in eachcore layer 210 center, the size of alabastrine artificial micro-structural 212 is maximum, and measure-alike in the artificial micro-structural 212 of flakes at distance center same radius place, therefore the effective dielectric constant of eachcore layer 210 by the centre to around diminish gradually, middle effective dielectric constant is maximum, thereby the refractive index of eachcore layer 210 is from the centre to diminishing gradually the refractive index maximum of mid portion all around.

The above is described embodiments of the invention by reference to the accompanying drawings, but the present invention is not limited to above-mentioned embodiment, the pattern of artificial micro-structural 212 can be two dimension, also can be three-dimensional structure, " worker " font that is not limited to use among this embodiment, can be the derived structure of " worker " font, can be each the orthogonal flakes in bar limit and alabastrine derived structure in three dimensions, it also can be other geometry, wherein different artificial micro-structurals 212 can be that pattern is identical, but its design size is different; Also can be that pattern is all not identical with design size, as long as can parallel ejaculation after the satisfied electromagnetic wave that is sent by antenna element is propagated through super material panel 20.

In the embodiment of the invention, the refractive index of eachcore layer 210 of described super material panel 20 is take its center as the center of circle, along with Changing Pattern such as the following formula of radius r:

$n\left(r\right)=n_{\max }-\frac{\sqrt{{\mathrm{<figure-callout\; label="ss"\; filenames="HDA0000078463300000011.png"\; state="\{\{state\}\}">ss</figure-callout>}}^2+r^2}-\mathrm{ss}}{2d};$

N in the formula_MaxRepresent the largest refractive index value in described eachcore layer 210, d represents the gross thickness of allcore layers 210, ss represents described feed 10 to the distance of thecore layer 210 of the most close feed position, and n (r) represents described eachcore layer 210 inside radius r place refractive index value.

Usually when electromagnetic wave from a kind of medium transmission to another kind of medium the time, because the problem of impedance mismatch, a part of reflection of electromagnetic wave can appear, affect so electromagnetic transmission performance, among the present invention, when inciding super material panel 20, the electromagnetic wave that radiates from feed 10 can produce reflection equally, in order to reduce reflection to the impact of radar antenna, we arrange a plurality of super material gradedbeddings 220 incore layer 210 1 sides of super material panel 20, as shown in Figure 3.

As shown in Figure 5, each super material gradedbedding 220 includesheet substrate layer 221, sheet the second packedlayer 223 and be arranged on describedsubstrate layer 221 and the second packedlayer 223 between air layer 222.Describedsubstrate layer 221 can be selected high molecular polymer, ceramic material, ferroelectric material, ferrite material etc.The wherein preferred FR-4 of high molecular polymer or F4B material.Refractive index between a plurality of super material gradedbeddings 220 is different, in order to mate the impedance of air andcore layer 210, the width by adjusting describedair layer 222 and realize impedance matching by the medium that contains different refractivity in the 223 interior fillings of the second packed layer normally, this medium also can be the material identical withsubstrate layer 221, also can be air, wherein the refractive index of the super material gradedbedding 220 of close air increases gradually near air and towardscore layer 210 direction refractive indexes.

Among the embodiment, 220 refractive index is equally distributed in each graded bedding of described super material panel 20, and Changing Pattern such as the following formula of 220 refraction index profile of a plurality of graded bedding among the present invention:

$n_i={\left(\frac{n_{\max }+n_{\min }}{2}\right)}^{\frac{i}{m}},$i＝1、2、3、...、m，

N wherein_iThe refractive index value that represents i layer gradedbedding 220, m represents the number of plies of gradedbedding 220, n_MinRepresent the minimum refractive index value in described eachcore layer 210, n_MaxRepresent the largest refractive index value in described eachcore layer 210, wherein m layer gradedbedding 220 is close withcore layer 210, along with diminishing of m value is the outermost layer graded bedding away from 210, the 1 layers of graded bedding of core layer gradually.

In sum, a kind of feed-forward type radar antenna of the present invention is by changing the refraction index profile situation of super material panel 20 inside, so that Antenna Far Field power strengthened widely, and then promoted the distance of antenna propagation, increased simultaneously the front and back ratio of antenna, so that antenna has more directivity.

Above-described embodiment is the better execution mode of the present invention; but embodiments of the present invention are not restricted to the described embodiments; other any do not run counter to change, the modification done under Spirit Essence of the present invention and the principle, substitutes, combination, simplify; all should be the substitute mode of equivalence, be included within protection scope of the present invention.

Claims (8)

1. feed-forward type radar antenna, described antenna comprises: feed is used for radiated electromagnetic wave; Super material panel, the electromagnetic wave that is used for described feed is given off is converted into plane electromagnetic wave from the sphere electromagnetic wave, it is characterized in that, described antenna also comprises the reflecting plate of being close to described super material panel one side, be used for reflection of electromagnetic wave converged to super material panel and reflect and to the distant place radiation, described super material panel comprises a plurality of a plurality of core layers with refractive index same distribution, described each core layer comprises a plurality of super material cell, described super material cell comprises unit base material and artificial micro-structural, the rounded distribution take its center as the center of circle of the refractive index of each core layer of described super material panel, and along with the increase refractive index of radius reduces gradually, and the refractive index that radius exists together mutually is identical, the refractive index of each core layer of described super material panel take its center as the center of circle along with Changing Pattern such as the following formula of radius r:

$n\left(r\right)=n_{\max }-\frac{\sqrt{{\mathrm{ss}}^2+r^2}-\mathrm{ss}}{2d};$

N in the formula_MaxRepresent the largest refractive index value in described each core layer, d represents the gross thickness of all core layers, and ss represents described feed to the distance of the core layer of the most close feed position, the described a plurality of core layer inside radius r of n (r) expression place refractive index value.

2. a kind of feed-forward type radar antenna according to claim 1, it is characterized in that, described super material cell also comprises the first packed layer, described artificial micro-structural between described unit base material and the first packed layer, the material of filling in described the first packed layer comprise air, artificial micro-structural and with the medium of described unit base material same material.

3. a kind of feed-forward type radar antenna according to claim 1, it is characterized in that, described super material panel also comprises a plurality of graded beddings that are distributed in described core layer one side, described each graded bedding include sheet substrate layer, sheet the second packed layer and be arranged on air layer between described substrate layer and the packed layer.

4. a kind of feed-forward type radar antenna according to claim 3 is characterized in that, the medium of filling in described the second packed layer comprise air and with the medium of described substrate layer same material.

5. a kind of feed-forward type radar antenna according to claim 3 is characterized in that, the refractive index in each graded bedding of described super material panel is equally distributed, and Changing Pattern such as the following formula of refraction index profile between a plurality of graded bedding:

$n_i={\left(\frac{n_{\max }+n_{\min }}{2}\right)}^{\frac{i}{m}},i=\mathrm{1,2,3},...,m,$

N wherein_iThe refractive index value that represents i layer graded bedding, m represents the number of plies of graded bedding, n_MinRepresent the minimum refractive index value in described each core layer, n_MaxRepresent the largest refractive index value in described each core layer, wherein m layer graded bedding and core layer are close, and along with diminishing gradually away from core layer of m value, the ground floor graded bedding is the outermost layer graded bedding.

6. a kind of feed-forward type radar antenna according to claim 1 is characterized in that, described artificial micro-structural is for to form planar structure or the stereochemical structure that electromagnetic field is had response by at least one one metal wire, and described wire is copper wire or filamentary silver.

7. a kind of feed-forward type radar antenna according to claim 6 is characterized in that, described wire is attached on the described unit base material by etching, plating, brill quarter, photoetching, electronics is carved or ion is carved method.

8. a kind of feed-forward type radar antenna according to claim 6 is characterized in that, described artificial micro-structural for the shape of deriving of " worker " font, " worker " font, flakes or alabastrine derive shape any one.

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