WO2013013468A1 - 偏馈式雷达天线 - Google Patents

偏馈式雷达天线 Download PDF

Info

Publication number
WO2013013468A1
WO2013013468A1 PCT/CN2011/082912 CN2011082912W WO2013013468A1 WO 2013013468 A1 WO2013013468 A1 WO 2013013468A1 CN 2011082912 W CN2011082912 W CN 2011082912W WO 2013013468 A1 WO2013013468 A1 WO 2013013468A1
Authority
WO
WIPO (PCT)
Prior art keywords
metamaterial
refractive index
artificial
core layer
layer
Prior art date
Application number
PCT/CN2011/082912
Other languages
English (en)
French (fr)
Inventor
刘若鹏
季春霖
岳玉涛
洪运南
Original Assignee
深圳光启高等理工研究院
深圳光启创新技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from CN 201110210454 external-priority patent/CN102480032B/zh
Priority claimed from CN201110210367.2A external-priority patent/CN103036039B/zh
Application filed by 深圳光启高等理工研究院, 深圳光启创新技术有限公司 filed Critical 深圳光启高等理工研究院
Publication of WO2013013468A1 publication Critical patent/WO2013013468A1/zh

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
    • H01Q15/0006—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices
    • H01Q15/0086—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices said selective devices having materials with a synthesized negative refractive index, e.g. metamaterials or left-handed materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/10—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/10—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
    • H01Q19/12—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave
    • H01Q19/13—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave the primary radiating source being a single radiating element, e.g. a dipole, a slot, a waveguide termination
    • H01Q19/132—Horn reflector antennas; Off-set feeding

Definitions

  • the present invention relates to the field of radar antennas, and more particularly to an offset feed radar antenna using a metamaterial (
  • the radar antenna converts the spherical wave radiated by the feed into a plane wave through the reflector, thereby achieving directional reception or transmitting electromagnetic waves.
  • the reflector currently used is a parabolic shape, and the feed is located near the focus of the reflector.
  • the working principle of the radar antenna is similar to that of the optical mirror.
  • the existing radar parabolic antenna is shown in Figure 1. It includes the source 1, the parabolic reflector 2 and the bracket 3.
  • the transmitting or receiving electromagnetic waves are placed at the focus of the parabolic reflector 2.
  • Feed 1 using the focusing characteristics of the parabolic reflector 2, the spherical wave emitted by the feed 1 is reflected by the parabolic reflector 2 and converted into a plane wave to form a narrow beam that radiates the strongest along the parabolic axial direction.
  • a parabolic reflecting surface In order to manufacture a parabolic reflecting surface, it is usually formed by mold casting or by a numerically controlled machine tool.
  • the process of the first method includes: making a parabolic mold, casting a paraboloid, and installing a parabolic reflector.
  • the process is relatively complicated, the cost is high, and the shape of the paraboloid is relatively accurate to achieve the directional propagation of the antenna, so the processing accuracy is relatively high.
  • the second method uses a large-scale CNC machine to perform paraboloid machining. By editing the program, the path of the tool in the CNC machine is controlled to cut the desired paraboloid shape. This method is very precise, but it is difficult and costly to manufacture such a large CNC machine.
  • Metamaterials are artificial composite structural materials that have extraordinary physical properties not found in natural materials. By superposing the ordered structure of the microstructure, the metamaterial can change the relative dielectric constant and magnetic permeability of each point in the metamaterial, and realize the non-uniformity of the refractive index distribution of the substance to control the propagation path of the electromagnetic wave in the material.
  • the object of the present invention is to overcome the problem of complicated manufacturing process of manufacturing a parabolic antenna in the prior art.
  • An offset feed radar antenna is provided, which proposes a simple radar antenna with a planar reflector, which has the advantage that a parabolic antenna can receive or emit electromagnetic waves directionally, and avoids the production of a parabolic antenna.
  • the complex process of time is provided, which proposes a simple radar antenna with a planar reflector, which has the advantage that a parabolic antenna can receive or emit electromagnetic waves directionally, and avoids the production of a parabolic antenna. The complex process of time.
  • An offset feed radar antenna comprising: a feed source for radiating electromagnetic waves; a metamaterial panel, an electromagnetic wave for radiating the feed source Converting from a spherical electromagnetic wave into a planar electromagnetic wave, the antenna further comprising a reflecting plate on one side of the metamaterial panel for reflecting electromagnetic waves to the metamaterial panel for concentrated refraction and radiating to a distant place, the feed source being located at the metamaterial The other side of the panel and in the non-facing region of the metamaterial panel, the metamaterial panel comprising a plurality of core layers having the same refractive index profile, each core layer comprising a plurality of metamaterial units, the metamaterial The unit includes a unit substrate provided with an artificial metal microstructure or an artificial hole structure, each core layer of the metamaterial panel including a semicircular area centered on an orthographic projection of the feed on each core layer And a plurality of semi-annular regions concentric with the semicircular region, in
  • the meta-material panel further includes a plurality of gradation layers distributed on one side of the core layer, each of the gradation layers including a sheet-like substrate layer, a sheet-shaped second filling layer, and a setting layer An air layer between the substrate layer and the second filling layer, wherein the medium filled in the second filling layer comprises air and a medium of the same material as the substrate layer.
  • the refractive index at the center of the circle is the maximum value " max , and the refractive index gradually decreases from the maximum value " max “ to the minimum value " mn “ as the radius increases; In the half annular region, the refractive index also decreases from the maximum value " max “ to the minimum value " mn “ as the radius increases.
  • the metamaterial unit further includes a first filling layer, the artificial metal microstructure is located between the unit substrate and the first filling layer, and the material filled in the first filling layer includes air and artificial a metal microstructure and a medium of the same material as the unit substrate.
  • the refractive index of each core layer of the metamaterial panel is the feed at each core
  • the orthographic projection on the layer is the center of the circle, and the variation law with the radius r is as follows:
  • max represents the maximum refractive index value in each core layer
  • d represents the total thickness of all core layers
  • ss represents the distance from the feed to the core layer closest to the feed position, indicating each of said a refractive index value at a radius r in the core layer, indicating a wavelength at which the feed radiates electromagnetic waves
  • mn indicates the minimum refractive index value in each core layer of the metamaterial panel, and floor indicates rounding down. Further, the refractive index in each graded layer of the metamaterial panel is uniformly distributed, and the variation of the refractive index distribution between the plurality of graded layers is as follows:
  • m represents the number of layers of the graded layer
  • mn represents the minimum refractive index in each core layer Value
  • max represents the maximum refractive index value in each core layer, wherein the m-th grade layer is close to the core layer, and gradually moves away from the core layer as the value of m becomes smaller, and the first layer is the outermost layer. Gradient layer.
  • the man-made metal microstructure is a planar structure or a three-dimensional structure composed of at least one wire responsive to an electromagnetic field, the wire being a copper wire or a silver wire.
  • the wire is attached to the unit substrate by etching, plating, drilling, photolithography, electron engraving or ion etching.
  • the man-made metal microstructure is any one of a derivative shape, a snow flower shape or a snowflake shape derived from a "work" shape or a "work” shape.
  • first substrate layer and the second substrate layer are each made of a ceramic material, an epoxy resin, a polytetrafluoroethylene, an FR-4 composite material or an F4B composite material.
  • each of the metamaterial units is formed with an artificial hole structure filled with a medium having a refractive index smaller than a refractive index of the unit substrate, and all the artificial holes in the metamaterial unit
  • the structure is filled with a medium of the same material, and the arrangement of the artificial pore structure volume disposed in the metamaterial unit in each core layer is: each core layer of the metamaterial panel includes one of the feeds
  • the orthographic projection on each core layer is a semicircular region of the center and a plurality of semi-annular regions concentric with the semicircular region, in which the metamaterial unit increases with increasing radius
  • the volume of the artificial pore structure formed thereon is also gradually increased; in each of the semi-annular regions, the volume of the artificial pore structure formed on the metamaterial unit increases with the increase of the radius, and the boundary between the two connected regions is increased.
  • a sudden change in the volume of the artificial pore structure occurs, that is, the volume of the artificial pore structure formed on the metamaterial unit at the junction is smaller when it is
  • each of the metamaterial units is formed with an artificial hole structure filled with a medium having a refractive index greater than a refractive index of the unit substrate, and the artificial hole structures in all the metamaterial units are filled.
  • the medium of the same material, the arrangement of the volume of the artificial pore structure disposed in the metamaterial unit in each core layer is: each core layer of the metamaterial panel includes one with each of the feeds
  • the orthographic projection on the core layer is a semicircular region of the center and a plurality of semicircular regions concentric with the semicircular region, in which the radius element is formed on the metamaterial unit as the radius increases
  • the volume of the artificial pore structure is reduced; in each of the semi-annular regions, the volume of the artificial pore structure formed on the metamaterial unit is gradually decreased as the radius increases, and the intersection of the two connected regions occurs artificially
  • the pore structure has a sudden change in volume, that is, the volume of the artificial pore structure formed on the metamaterial unit at the junction is larger when it is located in
  • each core layer of the metamaterial panel includes one of the feeds
  • the orthographic projection on each core layer is a semicircular region of the center and a plurality of semi-annular regions concentric with the semicircular region, in which the metamaterial unit increases with increasing radius
  • the number of the artificial hole structures formed thereon is gradually increased; in each of the semi-annular regions, the number of the artificial hole structures formed on the metamaterial unit increases with the increase of the radius, and the two connected regions are gradually increased.
  • each core layer of the metamaterial panel includes one of the feeds
  • the orthographic projection on each core layer is a semicircular region of the center and a plurality of semi-annular regions concentric with the semicircular region, in which the metamaterial unit increases with increasing radius
  • the number of the artificial hole structures formed thereon is gradually decreased; in each of the semi-annular regions, the number of the artificial hole structures formed on the metamaterial unit gradually decreases as the radius increases, and the boundary between the two connected regions A sudden change in the number of manhole structures occurs, that is, the number of manhole structures formed on the metamaterial unit at the junction is smaller than the
  • the present invention has the following beneficial effects:
  • An offset feed type radar antenna the structure of the planar antenna is simple, and the characteristics of the electromagnetic wave are concentrated by using the metamaterial, so that the radar antenna does not depend on the shape of the electromagnetic wave convergence device,
  • the complicated manufacturing process of processing a conventional parabolic antenna is eliminated, and at the same time, the advantages of the conventional parabolic antenna directional receiving or transmitting electromagnetic waves can be realized.
  • the present invention employs an offset-feeding radar antenna, so that the radiation of the electromagnetic wave is no longer blocked by the feed, and the influence of the radiated electromagnetic wave on the feed is also avoided.
  • FIG. 1 is a schematic structural view of a parabolic radar antenna in the prior art
  • FIG. 2 is a schematic diagram of an offset feed radar antenna according to a first embodiment of the present invention
  • FIG. 3 is a schematic diagram of an offset feed radar antenna according to a first embodiment of the present invention.
  • FIG. 4 is a schematic structural view of the metamaterial panel according to the first embodiment of the present invention.
  • FIG. 5 is a schematic structural diagram of the core layer according to the first embodiment of the present invention.
  • 6 is a schematic structural diagram of the core layer according to the first embodiment of the present invention
  • 7 is a schematic structural view of the metamaterial unit according to an embodiment of the present invention
  • FIG. 8 is a schematic structural view of the gradation layer according to an embodiment of the present invention.
  • Figure 9 is a schematic diagram showing changes in refractive index of a core layer according to an embodiment of the present invention.
  • Figure 10 is a schematic view showing the change of the refractive index of the core layer of the present invention.
  • Figure 11 is a schematic diagram of an offset feed radar of the present invention.
  • Figure 12 is a schematic diagram of an offset feed radar of the present invention.
  • Figure 13 is a schematic view showing the structure of the metamaterial panel of the present invention.
  • Figure 14 is a schematic view showing the structure of the core layer of the present invention.
  • Figure 15 is a schematic view showing the structure of the metamaterial unit of the present invention.
  • Figure 16 is a schematic view showing the structure of the gradation layer of the present invention.
  • FIGS. 2 and 3 are schematic diagrams showing the structure of an offset-fed radar antenna according to the present invention.
  • the antenna includes a feed 10, a meta-material panel 20, and a reflector 30.
  • the feed 10 and the emitter 30 are respectively located on the meta-material panel 20
  • the reflector 30 is closely attached to the metamaterial panel 20, and the orthographic projection of the point where the feed 10 is located on the metamaterial panel 20 is the midpoint of the bottom edge of the metamaterial panel 20.
  • the electromagnetic wave radiated from the feed 10 is a spherical electromagnetic wave, but the far-field direction performance of the spherical electromagnetic wave is not good, and the signal transmission with the spherical electromagnetic wave as a carrier at a long distance has a great limitation, and the attenuation is fast, and the present invention passes the feed.
  • a metamaterial panel 20 having an electromagnetic wave converging function is designed.
  • the metamaterial panel 20 converts most of the electromagnetic waves radiated from the feed 10 from spherical electromagnetic waves into planar electromagnetic waves, and electromagnetic waves passing through the primary metamaterial panel 20 After being reflected by the reflecting plate 30, it is again refracted and radiated through the metamaterial panel 20, so that the directivity of the radar antenna is better, the energy density of the main lobe of the antenna is higher, the energy is larger, and the signal transmission distance by using the plane electromagnetic wave as a carrier is further far.
  • the metamaterial panel 20 includes a plurality of a core layer 210 and a plurality of graded layers 220 distributed on the side close to the feed source 10, each of the core layers 210 being composed of a plurality of metamaterial units including a unit substrate 211 and a sheet-shaped portion
  • a filling layer 213 and a plurality of man-made metal microstructures 212 disposed between the unit substrate 211 and the first filling layer 213 are as shown in FIG. 6 and FIG.
  • the material filled in the first filling layer 213 may be air, an artificial metal microstructure 212, and a medium of the same material as the unit substrate 211, for example, when the equivalent refractive index in the metamaterial unit is required to be large.
  • the first filling layer 213 may be filled with a metal microstructure or filled with a medium having a large refractive index; when the equivalent refractive index in the metamaterial unit is required to be small, the first filling layer 213 may be filled.
  • the air medium is either not filled with any medium.
  • the plurality of metamaterial core layers 210 in the metamaterial panel 20 are stacked together, and the core layers 210 are assembled at equal intervals, or the front and back surfaces are integrally bonded together integrally between the two sheets.
  • the number of core layers of the metamaterial panel 20 and the distance between the core layers can be designed according to requirements.
  • Each of the metamaterial core layers 210 is formed by an array of a plurality of metamaterial elements, and the entire metamaterial core layer 210 can be regarded as an array of a plurality of metamaterial units arranged in three directions of X, Y, and ,, as shown in FIG. 5. Shown.
  • the plurality of core layers 210 of the metamaterial panel 20 realize phase radiation of electromagnetic waves or the like after passing through the metamaterial panel 20 by changing the refractive index distribution inside thereof, that is, realizing spherical electromagnetic wave conversion radiated from the feed source 10 It is a plane electromagnetic wave.
  • the refractive index distribution of each of the metamaterial core layers 210 is the same, and only the refractive index distribution of one of the supermaterial core layers 210 is described in detail.
  • Each metamaterial core Layer 210 includes a semi-circular region centered on the orthographic projection of feed 10 on each core layer 210 and a plurality of semi-annular regions having a radius greater than a semi-circular region and concentric with the semi-circular region, the center of the refraction
  • the rate is the largest, the semi-circular area or the semi-annular area having the same radius has the same refractive index, and in the semi-circular area, the refractive index gradually decreases as the radius increases; in each of the semi-annular areas, The refractive index of the radius increases gradually, and the refractive index abrupt changes at the junction of the two connected regions, that is, the refractive index at the junction is larger in the region with a larger radius than in the region with a smaller
  • the domain is bigger. For example: the intersection of the semicircular region and the semicircular region adjacent to the semicircular region, if the junction is in the semicircular region, its refractive index is smaller than that in the semicircular region The same is true for the two adjacent semi-annular regions.
  • a graph of the change of the refractive index in the r direction is given, that is, in the semicircular region, the refractive index decreases from the maximum value n max at the center of the circle to the minimum value n as the radius increases.
  • Mm also in the semi-annular region, but it should be understood that the refractive index change of the present invention is not limited thereto.
  • the design of the present invention is: When electromagnetic waves pass through the core layers 210 of each metamaterial, the deflection angle of the electromagnetic waves is gradually changed and finally radiated in parallel.
  • Sm ⁇ q* A «, where is the angle of the desired deflection electromagnetic wave, ⁇ « is the difference between the front and back refractive index changes, q is the thickness of the metamaterial functional layer and the required parameter value can be determined by computer simulation and The design purpose of the invention is achieved.
  • Figures 9 and 10 show views of the refractive index profile of the core layer of the metamaterial in the r direction.
  • the refractive index of electromagnetic waves is proportional to ⁇ ⁇ , where ⁇ is the magnetic permeability and ⁇ is the dielectric constant.
  • ⁇ is the magnetic permeability
  • ⁇ is the dielectric constant.
  • the electromagnetic wave will refract.
  • the refractive index distribution inside the substance is non-uniform, the electromagnetic wave is deflected toward a position where the refractive index is relatively large. Therefore, the refractive index of each point of the core layer 210 in the super-material panel 20 is designed to satisfy the above refractive index change rule.
  • the metamaterial unit is actually a cube rather than a point, the above semicircular area is only an approximate description, and the actual metamaterial units having the same or substantially the same refractive index are in a zigzag half circumference. Distributed on the top.
  • the specific design is similar to the programming mode (such as OpenGL) when the computer draws a semi-circular, semi-elliptical and other smooth curves with square pixels. When the pixel is small relative to the curve, the curve is smooth, and when the pixel is relatively The curve shows jagged when the curve is large.
  • the semiconductor substrate 211 is made of a dielectric insulating material, and may be a ceramic material, a polymer material, a ferroelectric material, a ferrite material, a ferromagnetic material, or the like.
  • the polymer material may be, for example, Epoxy or polytetrafluoroethylene.
  • the artificial metal microstructure 212 is a metal wire attached to the unit substrate 211 in a certain geometric shape and capable of responding to electromagnetic waves, and the metal wire may be a cross section.
  • the first filling layer 213 may be filled with a medium of different materials, may be the same material as the unit substrate 211, may be an artificial metal microstructure, or may be air.
  • Each of the core layers 210 is composed of a plurality of metamaterial units, each of which has an artificial metal microstructure, and each of the metamaterial units responds to electromagnetic waves passing therethrough, thereby affecting the transmission of electromagnetic waves therein.
  • the size of each metamaterial unit depends on the electromagnetic wave that needs to be responsive, typically one tenth of the wavelength of the electromagnetic wave that is required to respond, otherwise the arrangement of metamaterial units containing the artificial metal microstructure 212 in space cannot be Treated as continuous.
  • adjustment can be made by adjusting the pattern, size and spatial distribution of the artificial metal microstructure 212 on the unit substrate 211 and filling the first filling layer 213 with a medium having a different refractive index.
  • the equivalent dielectric constant and equivalent permeability throughout the metamaterial in turn alter the equivalent refractive index throughout the metamaterial.
  • the man-made metal microstructure 212 adopts the same geometry, the larger the size of the artificial metal microstructure at a certain point, the larger the equivalent dielectric constant and the larger the refractive index.
  • the pattern of the artificial metal microstructure 212 used in this embodiment is an I-shaped derivative pattern.
  • the size of the snow-like artificial metal microstructure 212 is centered on the orthographic projection of the feed 10 on each core layer 210. , as the radius increases, gradually becomes smaller, and then gradually decreases from the maximum value, such that it changes periodically, at which the snowflake-shaped artificial metal microstructure 212 has the largest size and is at the same radius.
  • the snowflake-like artificial metal microstructures 212 have the same size, so that the equivalent dielectric constant of each core layer 210 gradually changes with the increase of the radius, and the equivalent dielectric constant at the center of the circle is the largest, thus each core
  • the refractive index of the layer 210 changes periodically as the radius gradually increases, and the refractive index at the center of the circle is the largest.
  • the pattern of the artificial metal microstructures 212 may be two-dimensional or three-dimensional, and is not limited to the embodiment.
  • the "work" shape used may be a derivative structure of the "work” shape, which may be a snowflake-like and snowflake-like derivative structure in which each side of the three-dimensional space is perpendicular to each other, or may be other Geometry, wherein the different man-made metal microstructures may be the same pattern, but the design dimensions are different; the pattern and the design dimensions may be different, as long as the electromagnetic waves emitted by the antenna unit are propagated through the metamaterial panel 20 and can be emitted in parallel. Just fine.
  • the refractive index of each core layer 210 of the metamaterial panel is centered on the orthographic projection of the feed 10 on each core layer 210, and the variation law of the radius r is as follows:
  • max represents the maximum refractive index value in each core layer 210
  • d represents the total thickness of all core layers
  • ss represents the distance of the feed to the core layer closest to the feed position, indicating that each a refractive index value at a radius r in a core layer 210, indicating a wavelength at which a feed radiates electromagnetic waves
  • the smallest refractive index value in each core layer 210 in the mn table metamaterial panel, and floor indicates rounding down.
  • some electromagnetic wave reflection occurs due to the problem of impedance mismatch, which affects the transmission performance of the electromagnetic waves.
  • Reflections are also generated when the metamaterial panel 20 is applied.
  • each of the metamaterial grading layers 220 includes a sheet-like substrate layer 221, a sheet-shaped second filling layer 223, and an air layer 222 disposed between the substrate layer 221 and the second filling layer 223.
  • the substrate layer 221 may be a polymer, a ceramic material, a ferroelectric material, a ferrite material or the like.
  • the high molecular polymer is preferably a FR-4 or F4B material.
  • the refractive indices between the plurality of metamaterial graded layers 220 are different, in order to match the impedance of the air to the core layer 210, typically by adjusting the width of the air layer 222 and by filling the second fill layer 223 with different refractions.
  • the medium of the rate is used to achieve impedance matching.
  • the medium may also be the same material as the substrate layer 221 or air.
  • the refractive index of the metamaterial layer 220 close to the air is closest to the air and the refractive index of the super core layer 210 is gradually increased. .
  • the refractive index in each of the gradation layers 220 of the metamaterial panel 20 is uniform
  • the variation of the refractive index distribution between the distributed and multiple gradient layers 220 is as follows:
  • the core layer 210, the first layer of the gradient layer is the outermost layer.
  • the offset-feeding radar antenna of the present invention greatly increases the far-field power of the antenna by changing the refractive index distribution inside the super-material panel 20, thereby increasing the distance traveled by the antenna and increasing the antenna.
  • the front-to-back ratio makes the antenna more directional; and the invention adopts an offset-fed radar antenna, so that the feed 10 does not obstruct the electromagnetic wave radiation, and also avoids the influence of the radiated electromagnetic wave on the feed 10.
  • FIG. 11 and FIG. 12 are schematic diagrams showing the structure of an offset-fed radar antenna according to a second embodiment of the present invention.
  • the antenna includes a feed 10, a metamaterial panel 20', and a reflector 30.
  • the feed 10 and the emitter 30 are respectively located.
  • the reflector 30 is connected to the metamaterial panel 20', and the orthographic projection of the point where the feed 10 is located on the metamaterial panel 20' is in the lower edge of the metamaterial panel 20'. point.
  • the electromagnetic wave radiated from the feed 10 is a spherical electromagnetic wave, but the far-field direction performance of the spherical electromagnetic wave is not good, and the signal transmission with the spherical electromagnetic wave as a carrier at a long distance has a great limitation, and the attenuation is fast, and the present invention is designed by A metamaterial panel 20' having an electromagnetic wave concentrating function, the metamaterial panel 20' converts most of the electromagnetic waves radiated from the feed 10 from a spherical electromagnetic wave into a planar electromagnetic wave, and passes through the reflecting plate 30 through the electromagnetic wave passing through the primary metamaterial panel 20'.
  • the radar antenna After reflection, it is again condensed and radiated through the metamaterial panel 20', so that the directivity of the radar antenna is better, the energy density of the main lobe of the antenna is higher, the energy is larger, and the signal transmission distance of the plane electromagnetic wave is further.
  • the metamaterial panel 20' includes a plurality of core layers 210' having the same refractive index distribution and a plurality of graded layers 220' distributed on the side close to the feed source 10, that is, the core layer 210'
  • the functional layer of the metamaterial panel 10 is composed of a plurality of metamaterial units. Since the metamaterial panel 20' needs to continuously respond to electromagnetic waves, the size of the metamaterial unit should be less than one fifth of the wavelength of the required response electromagnetic wave. The embodiment is preferably one tenth of the wavelength of the electromagnetic wave.
  • the metamaterial unit includes a unit substrate 211' provided with one or more artificial hole structures 212', such that each core layer 210' provided with the artificial hole structure 212' is superposed to constitute
  • the functional layer of the metamaterial panel 20' is as shown in FIG.
  • the plurality of core layers 210' of the metamaterial panel 20' realize phase radiation of electromagnetic waves or the like after passing through the metamaterial panel 20' by changing the refractive index distribution inside thereof, that is, to be radiated from the feed source 10 Spherical electromagnetic waves are converted into planar electromagnetic waves.
  • the refractive index distribution of each of the metamaterial core layers 210' is the same, and only the refractive index distribution of one supermaterial core layer 210' will be described in detail herein. Further, the refractive index distribution of the metamaterial core layer 210' in this embodiment is the same as that of the previous embodiment.
  • each metamaterial core layer 210' is illustrated in Figure 10 by the design of the volume of the manhole structure 212', the medium filled within the manhole structure 212', and the density of the manhole structure 212'.
  • Each core layer 210' of the metamaterial panel 20 includes a semicircular region centered on the orthographic projection of the feed 10 on each core layer 210' and a plurality of semicircular regions concentric with the semicircular region.
  • the refractive index gradually decreases as the radius increases; in each of the semi-annular regions, the refractive index gradually decreases as the radius increases, and the junction of the two connected regions A refractive index abrupt change occurs, that is, the refractive index at the junction is larger when it is located in a region having a larger radius than in a region having a small radius.
  • the intersection of the semicircular region and the semicircular region adjacent to the semicircular region if the junction is in the semicircular region, its refractive index is smaller than that in the semicircular region The same is true for the two adjacent semi-annular regions.
  • Figure 9 and Figure 10 show the change in refractive index of nmax ⁇ n mm , that is, in the semi-circular area, the refractive index decreases from the maximum value n max at the center of the circle to the minimum value n mm as the radius increases. This is also true in the semi-annular region, but it should be understood that the refractive index change of the present invention is not limited thereto.
  • the design of the present invention is: When electromagnetic waves pass through the core layers 210' of each metamaterial, the deflection angle of the electromagnetic waves is gradually changed and finally radiated in parallel.
  • Figure 9 is a view showing the refractive index distribution of the core layer of the metamaterial shown in Figure 10 in the r direction.
  • the refractive index of electromagnetic waves is proportional to ⁇ ⁇ , where ⁇ is the magnetic permeability and ⁇ is the dielectric constant.
  • ⁇ is the magnetic permeability
  • ⁇ is the dielectric constant.
  • the meta-material unit is actually a cube rather than a point, the semi-circular area is only an approximate description, actually The supermaterial units having the same or substantially the same refractive index are distributed over a zigzag half circumference.
  • the specific design is similar to the programming mode (such as OpenGL) when the computer draws a semi-circular, semi-elliptical and other smooth curves with square pixels. When the pixel is small relative to the curve, the curve is smooth, and when the pixel is relatively The curve shows jagged when the curve is large.
  • the volume of the manhole structure 212', the medium filled in the manhole structure 212', and the density of the manhole structure 212' can be designed. Two preferred embodiments are discussed in detail below.
  • each core layer 210' of the metamaterial panel 20' is composed of a plurality of metamaterial units, each of which includes a unit substrate 211' provided with an artificial hole structure 212'.
  • Unit substrate 21 ⁇ Polymers, ceramic materials, ferroelectric materials, ferrite materials, etc. can be used. Among them, the high molecular polymer is preferably a FR-4 or F4B material.
  • the artificial hole structure 212' may be formed on the unit substrate 211' by different processes corresponding to different unit substrates 211'. For example, when the unit substrate 211' is selected from a high molecular polymer, it may be drilled or punched by a drill press or The artificial hole structure 212' is formed by injection molding or the like. When the unit base material 211' is selected from ceramics, the artificial hole structure 212 can be formed by drilling, punching, or high-temperature sintering.
  • the artificial hole structure 212' can be filled with a medium.
  • the medium filled in the artificial hole structure 212' is air, and the refractive index of the air is inevitably smaller than the refractive index of the unit substrate 211 ', when the artificial hole structure 212 The larger the volume, the smaller the refractive index of the metamaterial unit in which the artificial pore structure 212' is located.
  • each core layer 210' of the metamaterial panel includes one
  • the orthographic projection of the feed 10 on each core layer 210' is a semi-circular area of the center and a plurality of semi-annular areas concentric with the semi-circular area, in which the radius increases with Formed on the metamaterial unit
  • the volume of the artificial hole structure artificial hole structure 212' is also gradually increased; in each of the semi-annular regions, the volume of the artificial hole structure artificial hole structure 212' formed on the metamaterial unit increases with the increase of the radius.
  • a volumetric mutation of the artificial pore structure artificial pore structure 212' occurs at the junction of the two connected regions, that is, the volume of the artificial pore structure artificial pore structure 212' formed on the metamaterial unit at the junction is located at a large radius The area is smaller than when it is in a region with a small radius.
  • the semi-circular regions having the same radius or the artificial hole structure artificial hole structures 212' formed on the metamaterial units at the respective semi-annular regions are the same in volume. It is conceivable that when the artificial hole structure artificial hole structure 212' is filled with the same medium having a refractive index greater than that of the unit substrate 211', then the artificial hole structure artificial hole structure 212' is larger in volume, and the artificial hole structure artificial hole is enlarged.
  • the refractive index of the metamaterial unit occupied by the structure 212' is also larger, so that the arrangement of the artificial hole structure artificial hole structure 212' disposed in the metamaterial unit at this time in each core layer 210' will be the same as that of the artificial hole.
  • the arrangement of the air filled in the structural artificial hole structure 212' is completely opposite.
  • Another embodiment of the present invention is different from the first preferred embodiment in that a plurality of artificial hole structure artificial hole structures 212' having the same volume are present in each metamaterial unit, which can be simplified in the unit substrate 211' The process difficulty of setting the artificial hole structure artificial hole structure 212'.
  • the distribution rule of all the artificial hole structures in the super material unit in the super-material unit in the preferred embodiment is the same as that in the first preferred embodiment, that is, divided into two.
  • each core layer 210' of the panel 20' includes a semi-circular region centered on the orthographic projection of the feed 10 on each core layer 210' and a plurality of semi-annular regions concentric with the semi-circular region.
  • the number of the artificial hole structure artificial hole structures 212' formed on the metamaterial unit increases with the increase of the radius; in each of the semicircular regions, as the radius increases
  • the number of the artificial pore structure artificial pore structure 212' formed on the metamaterial unit is also gradually increased, and the number of the artificial pore structure artificial pore structure 212' is changed at the junction of the two connected regions, that is, The number of artificial hole structure artificial hole structures 212' formed at the interface on the metamaterial unit is less when located in a region having a larger radius than in a region having a smaller radius.
  • Semi-circular regions having the same radius or super-material elements formed at each semi-annular region The number of the artificial hole structure artificial hole structures 212' is the same.
  • the filling medium is air in all the artificial hole structure artificial hole structures 212'; (2) when the refractive index of the medium filled in all the artificial hole structure artificial hole structures 212' is larger than the refractive index of the substrate, And the artificial hole structure artificial hole structure 212' in all the metamaterial units is filled with a medium of the same material, and each core layer 210' of the metamaterial panel 20' includes one feed 10 on each core layer 210'.
  • the orthographic projection is a semicircular region of the center and a plurality of semi-annular regions concentric with the semicircular region, in which the artificial pore structure formed on the metamaterial unit with increasing radius
  • the number of the artificial hole structures 212' is gradually reduced; in each of the semi-annular regions, the number of the artificial hole structure artificial hole structures 212' formed on the metamaterial unit gradually decreases as the radius increases, and is connected
  • the number of artificial pore structure artificial pore structures 212' is abruptly formed at the junction of the two regions, that is, the number of artificial pore structure artificial pore structures 212' formed on the metamaterial unit at the junction is located at a large radius The area is much larger than when it is located in a small radius.
  • the number of the artificial hole structure artificial hole structures 212' formed on the metamaterial regions having the same radius or the metamaterial units at the respective semi-annular regions is the same.
  • the refractive index of each core layer 210' of the metamaterial panel 20' is centered on the orthographic projection of the feed 10 on each core layer 210', and the radius r varies according to the following rules. expression:
  • max represents the maximum refractive index value in each core layer 210'
  • d represents the total thickness of all core layers 210'
  • ss represents the feed source 10 to the core layer 210' closest to the feed position.
  • the distance, n(r) represents a refractive index value at a radius r in each core layer 210', indicating a wavelength at which the feed 10 radiates electromagnetic waves, wherein
  • each of the metamaterial grading layers 220' includes a sheet-shaped second substrate layer 221', a sheet-like filling layer 223', and a second substrate layer 221' and a filling layer 223'. Inter-air layer 222'.
  • the second substrate layer 221 ' can be selected from a polymer, a ceramic material, a ferroelectric material, a ferrite material, or the like. Among them, the high molecular polymer is preferably a FR-4 or F4B material.
  • the refractive index distribution within each graded layer 220' is uniform, and the refractive indices between the plurality of metamaterial graded layers are different.
  • Impedance matching is achieved by filling the filling layer 223' with a medium containing a different refractive index.
  • the medium may also be the same material as the second substrate layer 22 or air, wherein the metamaterial layer is close to the air.
  • the refractive index of 220' is closest to air and the refractive index of the super core layer 210' is gradually increased.
  • the refractive index in each of the graded layers 220' of the metamaterial panel 20' is uniformly distributed, and the variation of the refractive index distribution between the plurality of graded layers 220' is as follows:
  • the gradient layer is the outermost gradient layer.
  • the offset-feeding radar antenna of the present invention greatly increases the far-field power of the antenna by changing the refractive index distribution inside the super-material panel 20', thereby increasing the distance traveled by the antenna and increasing the distance.
  • the front-to-back ratio of the antenna makes the antenna more directional.
  • the invention adopts an offset-fed radar antenna, so that the radiation of the electromagnetic wave is no longer blocked by the feed 10, and the influence of the radiated electromagnetic wave on the feed 10 is also avoided.

Landscapes

  • Aerials With Secondary Devices (AREA)

Abstract

一种偏馈式雷达天线，包括：馈源（10）、超材料面板（20，20'）以及反射板（30），所述馈源（10）位于所述超材料面板（20，20'）的另一侧且在超材料面板（20，20'）的非对称区域，所述超材料面板（20，20'）包括多个具有相同折射率分布的核心层（210，210'），所述超材料面板（20，20'）的每一核心层（210，210'）由多个超材料单元组成，所述超材料单元包括设置有人造微金属结构（212）或人造孔结构（212'）的单元基材（211，211'）。所述偏馈式雷达天线通过改变超材料面板（20，20'）内部的折射率分布情况，使得天线远场功率大大地增强了，进而提升了天线传播的距离，同时增加了天线的前后比，使得天线更具方向性；采用了偏馈式雷达天线，使得馈源（10）对电磁波的辐射不再遮拦，同时也避免了辐射的电磁波对馈源（10）的影响。

Description

偏馈式雷达天线
【技术领域】
本发明涉及雷达天线领域， 特别是涉及一种使用超材料的偏馈式雷达天线 (
【背景技术】
雷达天线通过反射器将馈源辐射的球面波变为平面波， 从而实现定向接收 或者发射电磁波， 目前使用的反射器是抛物面形状， 馈源位于反射器的焦点附 近。
雷达天线的工作原理与光学反射镜相似， 现有的雷达抛物面天线如图 1 所 示， 包括溃源 1、 抛物面反射器 2和支架 3， 在抛物面反射器 2的焦点处放置有 发射或者接收电磁波的馈源 1， 利用抛物面反射器 2的聚焦特性， 由馈源 1发出 的球面波经抛物面反射器 2 反射后变换成平面波， 形成沿抛物面轴向辐射最强 的窄波束。
为了制造抛物反射面通常利用模具铸造成型或者采用数控机床进行加工的 方法。 第一种方法的工艺流程包括： 制作抛物面模具、 铸造成型抛物面和进行 抛物反射面的安装。 工艺比较复杂， 成本高， 而且抛物面的形状要比较准确才 能实现天线的定向传播， 所以对加工精度的要求也比较高。 第二种方法采用大 型数控机床进行抛物面的加工， 通过编辑程序， 控制数控机床中刀具所走路径， 从而切割出所需的抛物面形状。 这种方法切割很精确， 但是制造这种大型数控 机床比较困难， 而且成本比较高。
超材料是一种具有天然材料所不具备的超常物理性质的人工复合结构材 料。 超材料通过对微结构的有序排列， 可以改变超材料中每点的相对介电常数 和磁导率， 实现物质的折射率分布的非均匀性从而控制电磁波在材料中的传播 路径。
【发明内容】
本发明的目的在于克服现有技术中制造抛物面天线生产工艺复杂的问题， 提供一种偏馈式雷达天线， 该天线提出了一种结构简单的具有平面反射板的雷 达天线， 这种平面结构的天线具有抛物面天线可以定向接收或者发射电磁波的 优点， 同时避免了生产抛物面天线时的复杂工艺。
本发明解决其技术问题所采用的技术方案是： 提出一种偏馈式雷达天线， 所述天线包括： 馈源， 用于辐射电磁波； 超材料面板， 用于将所述馈源辐射出 的电磁波从球面电磁波转化为平面电磁波， 所述天线还包括位于超材料面板一 侧的反射板， 用于将电磁波反射到超材料面板进行汇聚折射并向远处辐射， 所 述馈源位于所述超材料面板的另一侧且在超材料面板的非正对区域， 所述超材 料面板包括多个具有相同折射率分布的核心层， 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设置有人造金属微结构或人造孔结构的单元基材， 所述超材料面板的每一核心层包括一个以所述馈源在每一核心层上的正投影为 圆心的半圆形区域和多个与半圆形区域同心的半环形区域， 在所述半圆形区域 内， 随着半径的增加折射率逐渐减小； 在所述每一半环形区域内， 随着半径的 增加折射率也逐渐减小， 且相连的两个区域的交界处发生折射率突变， 即交界 处的折射率位于半径大的区域时比位于半径小的区域时要大。
进一歩地， 所述超材料面板还包括分布于所述核心层一侧的多个渐变层， 所述每一渐变层均包括片状的基板层、 片状的第二填充层以及设置在所述基板 层和第二填充层之间的空气层， 所述第二填充层内填充的介质包括空气以及与 所述基板层相同材料的介质。
进一歩地， 在所述半圆形区域内， 圆心处的折射率为最大值《max， 且随着半 径的增加折射率从最大值《max逐渐减小到最小值《mn； 在所述每一半环形区域内， 随着半径的增加折射率也是从最大值《max逐渐减小到最小值《mn。
进一歩地， 所述超材料单元还包括第一填充层， 所述人造金属微结构位于 所述单元基材和第一填充层之间， 所述第一填充层内填充的材料包括空气、 人 造金属微结构以及与所述单元基材相同材料的介质。
进一歩地， 所述超材料面板的每一核心层的折射率以所述馈源在每一核心 层上的正投影为圆心， 随着半径 r的变化规律如以下表达式：
+ r2 - s -k
w0
Id
式中《max表示所述每一核心层中的最大折射率值， d表示所有核心层的总厚 度， ss表示所述馈源到最靠近馈源位置的核心层的距离， 表示所述每一核心 层内半径 r处折射率值， 表示馈源辐射出电磁波的波长， 其中，
Figure imgf000005_0001
«mn表示超材料面板中每一核心层内的最小折射率值， floor表示向下取整。 进一歩地， 所述超材料面板的每一渐变层内的折射率均匀分布的， 且多个 渐变层间折射率分布的变化规律如以下表达式：
ητ = ( max ^ mm )m , 1=1 2 3 m 其中 表示第 i层渐变层的折射率值， m表示渐变层的层数， 《mn表示所述 每一核心层内的最小折射率值， 《max表示所述每一核心层中的最大折射率值， 其 中第 m层渐变层与核心层靠近， 随着 m值的变小逐渐远离核心层， 第一层渐变 层为最外层渐变层。
进一歩地， 所述人造金属微结构为由至少一根金属丝组成对电磁场有响应 的平面结构或立体结构， 所述金属丝为铜丝或银丝。
进一歩地， 所述金属丝通过蚀刻、 电镀、 钻刻、 光刻、 电子刻或离子刻的 方法附着在所述单元基材上。
进一歩地， 所述人造金属微结构为在 "工"字形、 "工"字形的衍生形、 雪 花状或雪花状的衍生形任意一种。
进一歩地， 所述第一基板层和第二基板层均由陶瓷材料、 环氧树脂、 聚四 氟乙烯、 FR-4复合材料或 F4B复合材料制得。
进一歩地， 所述每一超材料单元上形成有一个人造孔结构， 所述人造孔结 构内填充有折射率小于单元基材折射率的介质， 且所有超材料单元内的人造孔 结构都填充相同材料的介质， 所述设置在超材料单元内的人造孔结构体积在每 一核心层内的排布规律为： 所述超材料面板的每一核心层包括一个以所述馈源 在每一核心层上的正投影为圆心的半圆形区域和多个与半圆形区域同心的半环 形区域， 在所述半圆形区域内， 随着半径的增加在所述超材料单元上形成的人 造孔结构体积也逐渐增加； 在所述每一半环形区域内， 随着半径的增加在所述 超材料单元上形成的人造孔结构体积也逐渐增加， 且相连的两个区域的交界处 发生人造孔结构体积突变， 即交界处在所述超材料单元上形成的人造孔结构体 积在位于半径大的区域时比位于半径小的区域时要小。
进一歩地， 所述每一超材料单元上形成有一个人造孔结构， 所述人造孔结 构内填充有折射率大于单元基材折射率的介质， 且所有超材料单元内的人造孔 结构都填充相同材料的介质， 所述设置在超材料单元内的人造孔结构体积在每 一核心层内的排布规律为： 所述超材料面板的每一核心层包括一个以所述馈源 在每一核心层上的正投影为圆心的半圆形区域和多个与半圆形区域同心的半环 形区域， 在所述半圆形区域内， 随着半径的增加在所述超材料单元上形成的人 造孔结构体积减小； 在所述每一半环形区域内， 随着半径的增加在所述超材料 单元上形成的人造孔结构体积也逐渐减小， 且相连的两个区域的交界处发生人 造孔结构体积突变， 即交界处在所述超材料单元上形成的人造孔结构体积在位 于半径大的区域时比位于半径小的区域时要大。
进一歩地， 所述超材料单元上形成有数量不同、 体积相同的人造孔结构， 所述人造孔结构内填充有折射率小于单元基材折射率的介质， 且所有超材料单 元内的人造孔结构都填充相同材料的介质， 所述设置在超材料单元内的人造孔 结构数量在每一核心层内的排布规律为： 所述超材料面板的每一核心层包括一 个以所述馈源在每一核心层上的正投影为圆心的半圆形区域和多个与半圆形区 域同心的半环形区域， 在所述半圆形区域内， 随着半径的增加在所述超材料单 元上形成的人造孔结构数量逐渐增加； 在所述每一半环形区域内， 随着半径的 增加在所述超材料单元上形成的人造孔结构数量也逐渐增加， 且相连的两个区 域的交界处发生人造孔结构数量突变， 即交界处在所述超材料单元上形成的人 造孔结构数量在位于半径大的区域时比位于半径小的区域时要少。
进一歩地， 所述超材料单元上形成有数量不同、 体积相同的人造孔结构， 所述人造孔结构内填充有折射率大于单元基材折射率的介质， 且所有超材料单 元内的人造孔结构都填充相同材料的介质， 所述设置在超材料单元内的人造孔 结构数量在每一核心层内的排布规律为： 所述超材料面板的每一核心层包括一 个以所述馈源在每一核心层上的正投影为圆心的半圆形区域和多个与半圆形区 域同心的半环形区域， 在所述半圆形区域内， 随着半径的增加在所述超材料单 元上形成的人造孔结构数量逐渐减小； 在所述每一半环形区域内， 随着半径的 增加在所述超材料单元上形成的人造孔结构数量逐渐减小， 且相连的两个区域 的交界处发生人造孔结构数量突变， 即交界处在所述超材料单元上形成的人造 孔结构数量在位于半径大的区域时比位于半径小的区域时要多。
本发明相对于现有技术， 具有以下有益效果： 一种偏馈式雷达天线， 平面 天线的结构简单， 通过利用超材料对电磁波进行汇聚的特性， 使得雷达天线不 依赖电磁波汇聚设备的形状， 省去了加工传统抛物面天线的复杂制造工艺， 同 时又可以实现传统抛物面天线定向接收或者发射电磁波的优点。 还有本发明采 用了偏馈式雷达天线， 使得馈源对电磁波的辐射不再遮拦， 同时也避免了辐射 的电磁波对馈源的影响。
【附图说明】
图 1是现有技术中抛物面雷达天线的结构示意图；
图 2是本发明第一实施例的一种偏馈式雷达天线示意图；
图 3是本发明第一实施例的一种偏馈式雷达天线示意图；
图 4是本发明第一实施例的所述超材料面板的结构示意图;
图 5是本发明第一实施例的所述核心层的结构示意图；
图 6是本发明第一实施例的所述核心层的结构示意图； 图 7是本发明 实施例的所述超材料单元的结构示意图；
图 8是本发明 实施例的所述渐变层结构示意图；
图 9是本发明 实施例的核心层折射率变化示意图；
图 10是本发明 ；一实施例的核心层折射率变化示意图；
图 11是本发明 ；二实施例的一种偏馈式雷达示意图；
图 12是本发明 ；二实施例的一种偏馈式雷达示意图；
图 13是本发明 ；二实施例的所述超材料面板的结构示意图;
图 14是本发明 ；二实施例的所述核心层的结构示意图；
图 15是本发明 ；二实施例的所述超材料单元结构示意图；
图 16是本发明 ；二实施例的所述渐变层结构示意图。
【具体实施方式】
下面结合实施例及附图， 对本发明作进一歩地详细说明， 但本发明的实施 方式不限于此。
图 2和图 3是本发明偏馈式雷达天线的结构示意图， 该天线包括馈源 10、 超材料面板 20以及反射板 30，所述馈源 10和发射板 30分别位于所述超材料面 板 20的两侧， 反射板 30与超材料面板 20紧贴相连， 馈源 10所在点在所述超 材料面板 20上的正投影为超材料面板 20下底边的中点。
通常从馈源 10辐射的电磁波是球面电磁波， 但是球面电磁波的远场方向性 能不好， 对于远距离以球面电磁波为载体的信号传输有很大的局限性， 而且衰 减快， 本发明通过在馈源 10传输方向上设计一具有电磁波汇聚功能的超材料面 板 20 ，该超材料面板 20将馈源 10辐射出来的大部分电磁波从球面电磁波转换 为平面电磁波， 且在通过一次超材料面板 20的电磁波经过反射板 30反射再次 通过超材料面板 20折射汇聚并辐射出去， 使得雷达天线的方向性更好， 天线主 瓣能量密度更高， 能量更大， 进而以该平面电磁波为载体的信号传输距离更远。
图 4是图 2所示的超材料面板 20的结构示意图， 超材料面板 20包括多个 核心层 210以及分布在靠近所述馈源 10—侧的多个渐变层 220，每一核心层 210 均由多个超材料单元组成， 所述超材料单元包括单元基材 211、 片状的第一填充 层 213以及设置在所述单元基材 211和第一填充层 213之间的多个人造金属微 结构 212， 如图 6以及如图 7所示。所述第一填充层 213内填充的材料可以是空 气、 人造金属微结构 212以及与所述单元基材 211相同材料的介质， 比如， 当 需要所述超材料单元内的等效折射率变大时， 可以在第一填充层 213 内填充金 属微结构或者是填充具有较大折射率的介质； 当需要所述超材料单元内的等效 折射率变小时， 可以在第一填充层 213内填充空气介质或者是不填充任何介质。 超材料面板 20内的多个超材料核心层 210堆叠在一起， 且各个核心层 210之间 等间距排列地组装， 或两两片层之间直接前、 后表面相粘合地连接成一体。 具 体实施时， 超材料面板 20的核心层的数目以及各个核心层之间的距离可依据需 求来进行设计。 每个超材料核心层 210 由多个超材料单元阵列形成， 整个超材 料核心层 210可看作是由多个超材料单元沿 X、 Y、 Ζ三个方向阵列排布而成， 如图 5所示。
所述超材料面板 20的多个核心层 210通过改变其内部的折射率分布以实现 通过所述超材料面板 20后的电磁波等相位辐射， 即实现从所述馈源 10辐射出 的球面电磁波转换为平面电磁波。 本发明中每个超材料核心层 210 的折射率分 布均相同， 这里仅对一个超材料核心层 210 的折射率分布规律进行详细描述。 通过对人造金属微结构 212的拓扑图案、 几何尺寸以及其在单元基材 211和第 一填充层 213上分布的设计， 使中间的核心层 210的折射率分布满足如下规律: 每一超材料核心层 210包括一个以以馈源 10在每一核心层 210上的正投影为圆 心的半圆形区域和多个半径大于半圆形区域且与半圆形区域同心的半环形区 域， 圆心处折射率最大， 具有相同半径的半圆形区域或者半环形区域处折射率 相同， 在所述半圆形区域内， 随着半径的增加折射率逐渐减小； 在所述每一半 环形区域内， 随着半径的增加折射率也逐渐减小， 且相连的两个区域的交界处 发生折射率突变， 即交界处的折射率在位于半径大的区域时比位于半径小的区 域时要大。 例如： 所述半圆形区域和与半圆形区域相邻的半环形区域的交界处， 如果该交界处位于半圆形区域时， 它的折射率比其位于半环形区域时的折射率 小； 同理相邻的两个半环形区域也如此。 如图 10所示， 给出了折射率在 r方向 上的变化图， 即在半圆形区域内，折射率随着半径的增加从圆心处的最大值 nmax 逐进减小到最小值 nmm， 在半环形区域也如此， 但是应知本发明的折射率变化并 不以此为限。 本发明设计目的为： 使电磁波经过各超材料核心层 210 时， 电磁 波偏折角度被逐渐改变并最终平行辐射。 通过公式 Sm^=q* A«， 其中 为所需 偏折电磁波的角度、 Δ«为前后折射率变化差值， q 为超材料功能层的厚度并通 过计算机仿真即可确定所需参数值并达到本发明设计目的。
图 9和图 10所示为超材料核心层折射率分布在 r方向上的视图。 作为公知 常识我们可知， 电磁波的折射率与 Λ ^成正比关系， 其中 μ为磁导率， ε为介电 常数， 当一束电磁波由一种介质传播到另外一种介质时， 电磁波会发生折射， 当物质内部的折射率分布非均匀时， 电磁波就会向折射率比较大的位置偏折， 因此， 设计超材料面板 20内核心层 210各点的折射率使其满足上述折射率变化 规律， 需要说明的是， 由于实际上超材料单元是一个立方体而非一个点， 因此 上述半圆形面域只是近似描述， 实际上的折射率相同或基本相同的超材料单元 是在一个锯齿形半圆周上分布的。 其具体设计类似于计算机用方形像素点绘制 半圆形、 半椭圆形等平滑曲线时进行描点的编程模式 （例如 OpenGL) , 当像素 点相对于曲线很小时曲线显示为光滑， 而当像素点相对于曲线较大时曲线显示 有锯齿。
为使超材料核心层 210实现图 9和图 10所示折射率的变化， 经过理论和实 际证明， 可对所述人造金属微结构 212 的拓扑图案、 几何尺寸以及其在单元基 材 211和第一填充层 213上分布的设计， 单元基材 211采用介电绝缘材料制成， 可以为陶瓷材料、 高分子材料、 铁电材料、 铁氧材料、 铁磁材料等， 高分子材 料例如可以是、 环氧树脂或聚四氟乙烯。 人造金属微结构 212 为以一定的几何 形状附着在单元基材 211 上能够对电磁波有响应的金属线， 金属线可以是剖面 为圆柱状或者扁平状的铜线、 银线等， 一般采用铜， 因为铜丝相对比较便宜， 当然金属线的剖面也可以为其他形状， 金属线通过蚀刻、 电镀、 钻刻、 光刻、 电子刻或离子刻等工艺附着在单元基材 211上， 所述第一填充层 213可以填充 不同材料的介质， 可以与单元基材 211相同的材料， 也可以是人造金属微结构， 还可以是空气， 所述每一核心层 210 由多个超材料单元组成， 每超材料单元都 具有一个人造金属微结构， 每一个超材料单元都会对通过其中的电磁波产生响 应， 从而影响电磁波在其中的传输， 每个超材料单元的尺寸取决于需要响应的 电磁波， 通常为所需响应的电磁波波长的十分之一， 否则空间中包含人造金属 微结构 212的超材料单元所组成的排列在空间中不能被视为连续。
在单元基材 211 的选定的情况下， 通过调整人造金属微结构 212的图案、 尺寸及其在单元基材 211上的空间分布和在第一填充层 213填充不同折射率的 介质， 可以调整超材料上各处的等效介电常数及等效磁导率进而改变超材料各 处的等效折射率。 当人造金属微结构 212采用相同的几何形状时， 某处人造金 属微结构的尺寸越大， 则该处的等效介电常数越大， 折射率也越大。
本实施例采用的人造金属微结构 212 的图案为工字形的衍生图案， 由图 5 可知， 雪花状人造金属微结构 212的尺寸从以馈源 10在每一核心层 210上的正 投影为圆心， 随着半径的增加逐渐变小为最小值， 然后又从最大值逐渐变小这 样周期性变化， 在所述圆心处， 雪花状的人造金属微结构 212 的尺寸最大， 并 且在相同半径处的雪花状人造金属微结构 212的尺寸相同，因此每一核心层 210 的等效介电常数随着半径的增加逐渐变小的周期性变化， 圆心处的等效介电常 数最大， 因而每一核心层 210的折射率随着半径的增加逐渐变小地周期性变化， 圆心处的折射率最大。
上面结合附图对本发明的实施例进行了描述， 但是本发明并不局限于上述 的具体实施方式， 人造金属微结构 212的图案可以是二维、 也可以是三维结构， 不限于该实施例中使用的 "工"字形， 可以为 "工"字形的衍生结构， 可以是 在三维空间中各条边相互垂直的雪花状及雪花状的衍生结构， 也可以是其他的 几何形状， 其中不同的人造金属微结构可以是图案相同， 但是其设计尺寸不同； 也可以是图案和设计尺寸均不相同， 只要满足由天线单元发出的电磁波经过超 材料面板 20传播后可以平行射出即可。
本发明实施例中， 所述超材料面板的每一核心层 210的折射率以馈源 10在 每一核心层 210上的正投影为圆心， 随着半径 r的变化规律如以下表达式：
Figure imgf000012_0001
式中《max表示所述每一核心层 210中的最大折射率值， d表示所有核心层的 总厚度， ss表示所述馈源到最靠近馈源位置的核心层的距离， 表示所述每一 核心层 210内半径 r处折射率值， 表示馈源辐射出电磁波的波长， 其中，
Figure imgf000012_0002
«mn表超材料面板中每一核心层 210内的最小折射率值， floor表示向下取整。 通常当电磁波从一种介质传输到另一种介质的时候， 由于阻抗不匹配的问 题， 会出现一部分电磁波反射， 这样影响电磁波的传输性能， 本发明中， 当从 馈源 10辐射出来的电磁波入射到超材料面板 20时同样会产生反射， 为了减少 反射对雷达天线的影响， 我们在超材料面板 20的核心层 210—侧堆成设置多个 超材料渐变层 220， 如图 4所示。
如图 8所示， 每一超材料渐变层 220均包括片状的基板层 221、片状的第二 填充层 223以及设置在所述基板层 221和第二填充层 223之间的空气层 222。所 述基板层 221 可选用高分子聚合物、 陶瓷材料、 铁电材料、 铁氧材料等。 其中 高分子聚合物优选 FR-4或 F4B材料。多个超材料渐变层 220之间的折射率是不 同的， 为了匹配空气与核心层 210的阻抗， 通常是通过调整所述空气层 222的 宽度和通过在第二填充层 223 内填充含有不同折射率的介质来实现阻抗匹配， 该介质也可以是与基板层 221 相同的材料也可以是空气， 其中靠近空气的超材 料渐变层 220的折射率最接近空气且超核心层 210方向折射率逐渐增加。
本发明中实施例中， 所述超材料面板 20的每一渐变层 220内的折射率均匀 分布的， 且多个渐变层 220间折射率分布的变化规律如以下表达式：
ητ = ( max ^ mm )m , 1=1、 2、 3、 …、 m， 其中 表示第 i层渐变层 220的折射率值， m表示渐变层 220的层数，《mn表 示所述每一核心层 210内的最小折射率值， 《max表示所述每一核心层 210中的最 大折射率值， 其中第 m层渐变层 220与核心层 210靠近， 随着 m值的变小逐渐 远离核心层 210， 第 1层渐变层为最外层渐变层。
综上所述， 本发明的一种偏馈式雷达天线通过改变超材料面板 20内部的折 射率分布情况， 使得天线远场功率大大地增强了， 进而提升了天线传播的距离， 同时增加了天线的前后比， 使得天线更具方向性； 还有本发明采用了偏馈式雷 达天线， 使得馈源 10对电磁波的辐射不再遮拦， 同时也避免了辐射的电磁波对 馈源 10的影响。
图 11和图 12是本发明第二实施例的偏馈式雷达天线的结构示意图， 该天 线包括馈源 10、 超材料面板 20'以及反射板 30， 所述馈源 10和发射板 30分别 位于所述超材料面板 20'的两侧， 反射板 30与超材料面板 20'相连， 馈源 10所 在点在所述超材料面板 20'上的正投影为超材料面板 20'下底边的中点。
通常从馈源 10辐射的电磁波是球面电磁波， 但是球面电磁波的远场方向性 能不好， 对于远距离以球面电磁波为载体的信号传输有很大的局限性， 而且衰 减快， 本发明通过设计一具有电磁波汇聚功能的超材料面板 20'， 该超材料面板 20'将馈源 10辐射出来的大部分电磁波从球面电磁波转换为平面电磁波，且在通 过一次超材料面板 20'的电磁波经过反射板 30反射后再次通过超材料面板 20' 折射汇聚并辐射出去， 使得雷达天线的方向性更好， 天线主瓣能量密度更高， 能量更大， 进而以该平面电磁波为载体的信号传输距离更远。
图 13所示，所述超材料面板 20'包括多个具有相同折射率分布的核心层 210' 以及分布在靠近馈源 10—侧的多个渐变层 220'，所述核心层 210'也就是超材料 面板 10的功能层， 由多个超材料单元组成， 由于超材料面板 20 ' 需对电磁波产 生连续响应， 因此超材料单元尺寸应小于所需响应电磁波波长的五分之一， 本 实施例优选为电磁波波长的十分之一。 如图 15所示， 所述超材料单元包括设置 有一个或多个人造孔结构 212'的单元基材 211 '， 这样设置有人造孔结构 212'的 每一核心层 210'叠加在一起就构成超材料面板 20'的功能层， 如图 14所示。
所述超材料面板 20'的多个核心层 210'通过改变其内部的折射率分布以实现 通过所述超材料面板 20'后的电磁波等相位辐射， 即实现从所述馈源 10辐射出 的球面电磁波转换为平面电磁波。本发明中每个超材料核心层 210 ' 的折射率分 布均相同， 这里仅对一个超材料核心层 210' 的折射率分布规律进行详细描述。 并且， 本实施例中的超材料核心层 210 ' 的折射率分布与上一实施例相同。通过 对人造孔结构 212' 的体积、 人造孔结构 212' 内填充的介质以及人造孔结构 212' 的密度的设计使得每个超材料核心层 210' 的折射率分布如图 10所示。所 述超材料面板 20的每一核心层 210'包括一个以馈源 10在每一核心层 210' 上的 正投影为圆心的半圆形区域和多个与半圆形区域同心的半环形区域， 在所述半 圆形区域内， 随着半径的增加折射率逐渐减小； 在所述每一半环形区域内， 随 着半径的增加折射率也逐渐减小， 且相连的两个区域的交界处发生折射率突变， 即交界处的折射率在位于半径大的区域时比位于半径小的区域时要大。 例如： 所述半圆形区域和与半圆形区域相邻的半环形区域的交界处， 如果该交界处位 于半圆形区域时， 它的折射率比其位于半环形区域时的折射率小； 同理相邻的 两个半环形区域也如此。 图 9和图 10中给出 nmax~ nmm的折射率变化图， 即在半 圆形区域内， 折射率随着半径的增加从圆心处的最大值 nmax逐进减小到最小值 nmm， 在半环形区域也如此， 但是应知本发明的折射率变化并不以此为限。 本发 明设计目的为： 使电磁波经过各超材料核心层 210'时， 电磁波偏折角度被逐渐 改变并最终平行辐射。通过公式 Sm^=q* A«， 其中 为所需偏折电磁波的角度、 ^为前后折射率变化差值， q为超材料功能层的厚度并通过计算机仿真即可确 定所需参数值并达到本发明设计目的。
图 9为图 10所示超材料核心层折射率分布在 r方向上的视图。 作为公知常 识我们可知， 电磁波的折射率与 Λ ^成正比关系， 其中 μ为磁导率， ε为介电常 数， 当一束电磁波由一种介质传播到另外一种介质时， 电磁波会发生折射， 当 物质内部的折射率分布非均匀时， 电磁波就会向折射率比较大的位置偏折， 因 此， 设计超材料面板 20' 各点的折射率使其满足上述折射率变化规律， 需要说 明的是， 由于实际上超材料单元是一个立方体而非一个点， 因此上述半圆形面 域只是近似描述， 实际上的折射率相同或基本相同的超材料单元是在一个锯齿 形半圆周上分布的。 其具体设计类似于计算机用方形像素点绘制半圆形、 半椭 圆形等平滑曲线时进行描点的编程模式 （例如 OpenGL) , 当像素点相对于曲线 很小时曲线显示为光滑， 而当像素点相对于曲线较大时曲线显示有锯齿。
为使功能层实现图 9和图 10所示折射率的变化， 可对人造孔结构 212'的体 积、 人造孔结构 212'内填充的介质以及人造孔结构 212'的密度进行设计。 下面 详细论述两种较佳实施方式。
如图 14所示， 超材料面板 20'的每一核心层 210'由多个超材料单元组成， 每一超材料单元包括设置有一个人造孔结构 212'的单元基材 211 '。单元基材 21Γ 可选用高分子聚合物、 陶瓷材料、 铁电材料、 铁氧材料等。 其中高分子聚合物 优选 FR-4或 F4B材料。对应不同的单元基材 211 '可采用不同的工艺在单元基材 211 '上形成人造孔结构 212'， 例如当单元基材 211 '选用高分子聚合物时， 可通 过钻床钻孔、 冲压成型或者注塑成型等方式形成人造孔结构 212'， 当单元基材 211 '选用陶瓷时则可通过钻床钻孔、冲压成型或者高温烧结等方式形成人造孔结 构 212，。
人造孔结构 212'内可填充介质， 本较佳实施方式中， 人造孔结构 212'内填 充的介质均为空气， 而空气折射率必然小于单元基材 211 '的折射率， 当人造孔 结构 212'体积越大时， 人造孔结构 212'所在的超材料单元的折射率则越小。 本 较佳实施方式中， 设置在超材料单元内的人造孔结构 212'的体积在每一核心层 210'内的排布规律为： 所述超材料面板的每一核心层 210'包括一个以馈源 10在 每一核心层 210'上的正投影为圆心的半圆形区域和多个与半圆形区域同心的半 环形区域， 在所述半圆形区域内， 随着半径的增加在所述超材料单元上形成的 人造孔结构人造孔结构 212'的体积也逐渐增加； 在所述每一半环形区域内， 随 着半径的增加在所述超材料单元上形成的人造孔结构人造孔结构 212'的体积也 逐渐增加， 且相连的两个区域的交界处发生人造孔结构人造孔结构 212'的体积 突变， 即交界处在所述超材料单元上形成的人造孔结构人造孔结构 212'的体积 在位于半径大的区域时比位于半径小的区域时要小。 具有相同半径的半圆形区 域或者各个半环形区域处的超材料单元上形成的人造孔结构人造孔结构 212'的 体积相同。 可以想象地， 当人造孔结构人造孔结构 212'内填充有折射率大于单 元基材 211 '的同种介质时， 则此时人造孔结构人造孔结构 212'体积越大， 人造 孔结构人造孔结构 212'所占据的超材料单元的折射率亦越大， 因此此时设置在 超材料单元内的人造孔结构人造孔结构 212'在每一核心层 210'内的排布规律将 与人造孔结构人造孔结构 212'内填充空气的排布规律完全相反。
本发明的另一实施例， 与第一较佳实施方式的不同点在于， 每一超材料单 元中存在多个体积相同的人造孔结构人造孔结构 212'， 这样能简化在单元基材 211 '上设置人造孔结构人造孔结构 212'的工艺难度。与第一较佳实施方式相同的 地方在于， 本较佳实施方式中每一超材料单元中所有人造孔结构占超材料单元 的体积的分布规律与第一较佳实施方式相同， 即分为两种情况： （1 ) 所有人造 孔结构内填充的介质折射率小于单元基材折射率时， 且所有超材料单元内的人 造孔结构人造孔结构 212'都填充相同材料的介质，所述超材料面板 20'的每一核 心层 210'包括一个以馈源 10在每一核心层 210'上的正投影为圆心的半圆形区域 和多个与半圆形区域同心的半环形区域， 在所述半圆形区域内， 随着半径的增 加在所述超材料单元上形成的人造孔结构人造孔结构 212'的数量逐渐增加； 在 所述每一半环形区域内， 随着半径的增加在所述超材料单元上形成的人造孔结 构人造孔结构 212'的数量也逐渐增加， 且相连的两个区域的交界处发生人造孔 结构人造孔结构 212'的数量突变， 即交界处在所述超材料单元上形成的人造孔 结构人造孔结构 212'的数量在位于半径大的区域时比位于半径小的区域时要 少。 具有相同半径的半圆形区域或者各个半环形区域处的超材料单元上形成的 人造孔结构人造孔结构 212'的数量相同。 本较佳实施方式即为此种情况且所有 人造孔结构人造孔结构 212'内填充介质为空气； （2) 所有人造孔结构人造孔结 构 212'内填充的介质折射率大于基板折射率时， 且所有超材料单元内的人造孔 结构人造孔结构 212'都填充相同材料的介质，所述超材料面板 20'的每一核心层 210'包括一个以馈源 10在每一核心层 210'上的正投影为圆心的半圆形区域和多 个与半圆形区域同心的半环形区域， 在所述半圆形区域内， 随着半径的增加在 所述超材料单元上形成的人造孔结构人造孔结构 212'的数量逐渐减小； 在所述 每一半环形区域内， 随着半径的增加在所述超材料单元上形成的人造孔结构人 造孔结构 212'的数量逐渐减小， 且相连的两个区域的交界处发生人造孔结构人 造孔结构 212'的数量突变， 即交界处在所述超材料单元上形成的人造孔结构人 造孔结构 212'的数量在位于半径大的区域时比位于半径小的区域时要多。 具有 相同半径的半圆形区域或者各个半环形区域处的超材料单元上形成的人造孔结 构人造孔结构 212'的数量相同。
本发明实施例中，所述超材料面板 20'的每一核心层 210'的折射率以馈源 10 在每一核心层 210' 上的正投影为圆心， 随着半径 r的变化规律如以下表达式：
Figure imgf000017_0001
式中《max表示所述每一核心层 210'中的最大折射率值， d表示所有核心层 210'的总厚度， ss表示所述馈源 10到最靠近馈源位置的核心层 210'的距离， n(r) 表示所述每一核心层 210'内半径 r处折射率值， 表示馈源 10辐射出电磁波的 波长， 其中，
Figure imgf000017_0002
«mn表超材料面板 20'中每一核心层 210'内的最小折射率值， floor表示向下 取整。
通常当电磁波从一种介质传输到另一种介质的时候， 由于阻抗不匹配的问 题， 会出现一部分电磁波反射， 这样影响电磁波的传输性能， 本发明中， 当从 馈源 10辐射出来的电磁波入射到超材料面板 20'时同样会产生反射， 为了减少 反射对雷达天线的影响，我们在超材料面板 20'的核心层 210'—侧堆成设置多个 超材料渐变层 220'， 如图 13所示。
如图 16所示， 每一超材料渐变层 220'均包括片状的第二基板层 221 '、 片状 的填充层 223'以及设置在所述第二基板层 221 '和填充层 223'之间的空气层 222'。 第二基板层 221 '可选用高分子聚合物、 陶瓷材料、 铁电材料、 铁氧材料等。 其 中高分子聚合物优选 FR-4或 F4B材料。每一渐变层 220'内的折射率分布是均匀 的， 多个超材料渐变层之间的折射率是不同的， 为了匹配空气与核心层 210'的 阻抗， 通常是通过调整所述空气层 222'的距离和通过在填充层 223'内填充含有 不同折射率的介质来实现阻抗匹配， 该介质也可以是与第二基板层 22Γ相同的 材料也可以是空气， 其中靠近空气的超材料渐变层 220'的折射率最接近空气且 超核心层 210'方向折射率逐渐增加。
本发明中实施例中，所述超材料面板 20'的每一渐变层 220'内的折射率均匀 分布的， 且多个渐变层 220'间折射率分布的变化规律如以下表达式：
ητ = ( max ^ mm )m , 1=1、 2、 3、 …、 m， 其中 表示第 i层渐变层的折射率值， m表示渐变层的层数， 《mn表示所述 每一核心层内的最小折射率值， 《max表示所述每一核心层中的最大折射率值， 其 中第 m层渐变层与核心层靠近， 随着 m值的变小逐渐远离核心层， 第一层渐变 层为最外层渐变层。
综上所述， 本发明的一种偏馈式雷达天线通过改变超材料面板 20'内部的折 射率分布情况， 使得天线远场功率大大地增强了， 进而提升了天线传播的距离， 同时增加了天线的前后比， 使得天线更具方向性； 本发明采用了偏馈式雷达天 线， 使得馈源 10对电磁波的辐射不再遮拦， 同时也避免了辐射的电磁波对馈源 10的影响。
上述实施例为本发明较佳的实施方式， 但本发明的实施方式并不受上述实 施例的限制， 其他的任何未违背本发明的精神实质与原理下所作的改变、 修饰、 替代、 组合、 简化， 均应为等效的置换方式， 都包含在本发明的保护范围之内。

Claims

权 利 要求
1、 一种偏馈式雷达天线， 所述天线包括： 馈源， 用于辐射电磁波； 超材料 面板， 用于将所述馈源辐射出的电磁波从球面电磁波转化为平面电磁波， 其特 征在于， 所述天线还包括位于超材料面板一侧的反射板， 用于将电磁波反射到 超材料面板进行汇聚折射并向远处辐射， 所述馈源位于所述超材料面板的另一 侧且在超材料面板的非正对区域， 所述超材料面板包括多个具有相同折射率分 布的核心层， 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设置 有人造金属微结构或人造孔结构的单元基材， 所述超材料面板的每一核心层包 括一个以所述馈源在每一核心层上的正投影为圆心的半圆形区域和多个与半圆 形区域同心的半环形区域， 在所述半圆形区域内， 随着半径的增加折射率逐渐 减小； 在所述每一半环形区域内， 随着半径的增加折射率也逐渐减小， 且相连 的两个区域的交界处发生折射率突变， 即交界处的折射率位于半径大的区域时 比位于半径小的区域时要大。
2、 根据权利要求 1所述的一种偏馈式雷达天线， 其特征在于， 所述超材料 面板还包括分布于所述核心层一侧的多个渐变层， 所述每一渐变层均包括片状 的基板层、 片状的第二填充层以及设置在所述基板层和第二填充层之间的空气 层， 所述第二填充层内填充的介质包括空气以及与所述基板层相同材料的介质。
3、 根据权利要求 1所述的一种偏馈式雷达天线， 其特征在于， 在所述半圆 形区域内，圆心处的折射率为最大值《max，且随着半径的增加折射率从最大值 逐渐减小到最小值《mn； 在所述每一半环形区域内， 随着半径的增加折射率也是 从最大值《max逐渐减小到最小值《mn。
4、 根据权利要求 1所述的一种偏馈式雷达天线， 其特征在于， 所述超材料 单元还包括第一填充层， 所述人造金属微结构位于所述单元基材和第一填充层 之间， 所述第一填充层内填充的材料包括空气、 人造金属微结构以及与所述单 元基材相同材料的介质。
5、 根据权利要求 1所述的一种偏馈式雷达天线， 其特征在于， 所述超材料 面板的每一核心层的折射率以所述馈源在每一核心层上的正投影为圆心， 随着 半径 r的变化规律如以下表达式：
+ r2 - s -k
n(r) = nt
2d
式中《max表示所述每一核心层中的最大折射率值， d表示所有核心层的总厚 度， ss表示所述馈源到最靠近馈源位置的核心层的距离， 表示所述每一核心 层内半径 r处折射率值， 表示馈源辐射出电磁波的波长， 其中，
Figure imgf000021_0001
«mn表示超材料面板中每一核心层内的最小折射率值， floor表示向下取整。
6、 根据权利要求 1所述的一种偏馈式雷达天线， 其特征在于， 所述超材料 面板的每一渐变层内的折射率均匀分布的， 且多个渐变层间折射率分布的变化 规律如以下表达式：
ητ = , 1=1、 2、 3、 …、 m，
Figure imgf000021_0002
其中 表示第 i层渐变层的折射率值， m表示渐变层的层数， 《mn表示所述 每一核心层内的最小折射率值， 《max表示所述每一核心层中的最大折射率值， 其 中第 m层渐变层与核心层靠近， 随着 m值的变小逐渐远离核心层， 第一层渐变 层为最外层渐变层。
7、 根据权利要求 1所述的一种偏馈式雷达天线， 其特征在于， 所述人造金 属微结构为由至少一根金属丝组成对电磁场有响应的平面结构或立体结构， 所 述金属丝为铜丝或银丝。
8、 根据权利要求 7所述的一种偏馈式雷达天线， 其特征在于， 所述金属丝 通过蚀刻、 电镀、 钻刻、 光刻、 电子刻或离子刻的方法附着在所述单元基材上。
9、 根据权利要求 7所述的一种偏馈式雷达天线， 其特征在于， 所述人造金 属微结构为在 "工"字形、 "工"字形的衍生形、 雪花状或雪花状的衍生形任意 一种。
10、 根据权利要求 1 所述的一种偏馈式雷达天线， 其特征在于， 所述第一 基板层和第二基板层均由陶瓷材料、 环氧树脂、 聚四氟乙烯、 FR-4复合材料或 F4B复合材料制得。
11、 根据权利要求 1 所述的一种偏馈式雷达天线， 其特征在于， 所述每一 超材料单元上形成有一个人造孔结构， 所述人造孔结构内填充有折射率小于单 元基材折射率的介质， 且所有超材料单元内的人造孔结构都填充相同材料的介 质， 所述设置在超材料单元内的人造孔结构体积在每一核心层内的排布规律为： 所述超材料面板的每一核心层包括一个以所述馈源在每一核心层上的正投影为 圆心的半圆形区域和多个与半圆形区域同心的半环形区域， 在所述半圆形区域 内， 随着半径的增加在所述超材料单元上形成的人造孔结构体积也逐渐增加； 在所述每一半环形区域内， 随着半径的增加在所述超材料单元上形成的人造孔 结构体积也逐渐增加， 且相连的两个区域的交界处发生人造孔结构体积突变， 即交界处在所述超材料单元上形成的人造孔结构体积在位于半径大的区域时比 位于半径小的区域时要小。
12、 根据权利要求 1 所述的一种偏馈式雷达天线， 其特征在于， 所述每一 超材料单元上形成有一个人造孔结构， 所述人造孔结构内填充有折射率大于单 元基材折射率的介质， 且所有超材料单元内的人造孔结构都填充相同材料的介 质， 所述设置在超材料单元内的人造孔结构体积在每一核心层内的排布规律为： 所述超材料面板的每一核心层包括一个以所述馈源在每一核心层上的正投影为 圆心的半圆形区域和多个与半圆形区域同心的半环形区域， 在所述半圆形区域 内， 随着半径的增加在所述超材料单元上形成的人造孔结构体积减小； 在所述 每一半环形区域内， 随着半径的增加在所述超材料单元上形成的人造孔结构体 积也逐渐减小， 且相连的两个区域的交界处发生人造孔结构体积突变， 即交界 处在所述超材料单元上形成的人造孔结构体积在位于半径大的区域时比位于半 径小的区域时要大。
13、 根据权利要求 1 所述的一种偏馈式雷达天线， 其特征在于， 所述超材 料单元上形成有数量不同、 体积相同的人造孔结构， 所述人造孔结构内填充有 折射率小于单元基材折射率的介质， 且所有超材料单元内的人造孔结构都填充 相同材料的介质， 所述设置在超材料单元内的人造孔结构数量在每一核心层内 的排布规律为： 所述超材料面板的每一核心层包括一个以所述馈源在每一核心 层上的正投影为圆心的半圆形区域和多个与半圆形区域同心的半环形区域， 在 所述半圆形区域内， 随着半径的增加在所述超材料单元上形成的人造孔结构数 量逐渐增加； 在所述每一半环形区域内， 随着半径的增加在所述超材料单元上 形成的人造孔结构数量也逐渐增加， 且相连的两个区域的交界处发生人造孔结 构数量突变， 即交界处在所述超材料单元上形成的人造孔结构数量在位于半径 大的区域时比位于半径小的区域时要少。
14、 根据权利要求 1 所述的一种偏馈式雷达天线， 其特征在于， 所述超材 料单元上形成有数量不同、 体积相同的人造孔结构， 所述人造孔结构内填充有 折射率大于单元基材折射率的介质， 且所有超材料单元内的人造孔结构都填充 相同材料的介质， 所述设置在超材料单元内的人造孔结构数量在每一核心层内 的排布规律为： 所述超材料面板的每一核心层包括一个以所述馈源在每一核心 层上的正投影为圆心的半圆形区域和多个与半圆形区域同心的半环形区域， 在 所述半圆形区域内， 随着半径的增加在所述超材料单元上形成的人造孔结构数 量逐渐减小； 在所述每一半环形区域内， 随着半径的增加在所述超材料单元上 形成的人造孔结构数量逐渐减小， 且相连的两个区域的交界处发生人造孔结构 数量突变， 即交界处在所述超材料单元上形成的人造孔结构数量在位于半径大 的区域时比位于半径小的区域时要多。
PCT/CN2011/082912 2011-07-26 2011-11-25 偏馈式雷达天线 WO2013013468A1 (zh)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
CN 201110210454 CN102480032B (zh) 2011-07-26 2011-07-26 一种偏馈式雷达天线
CN201110210454.8 2011-07-26
CN201110210367.2A CN103036039B (zh) 2011-07-26 2011-07-26 一种偏馈式雷达天线
CN201110210367.2 2011-07-26

Publications (1)

Publication Number Publication Date
WO2013013468A1 true WO2013013468A1 (zh) 2013-01-31

Family

ID=47600508

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2011/082912 WO2013013468A1 (zh) 2011-07-26 2011-11-25 偏馈式雷达天线

Country Status (1)

Country Link
WO (1) WO2013013468A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112147588A (zh) * 2020-10-14 2020-12-29 中国电波传播研究所（中国电子科技集团公司第二十二研究所） 一种不对称的雷达照射面积快速计算方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002073740A1 (en) * 2001-03-12 2002-09-19 Wildblue Communications, Inc. Multi-band antenna for bundled broadband satellite internet access and dbs television service
US20090201572A1 (en) * 2008-02-07 2009-08-13 Toyota Motor Engineering & Manufacturing North America, Inc. Metamaterial gradient index lens
CN101587990A (zh) * 2009-07-01 2009-11-25 东南大学 基于人工电磁材料的宽带圆柱形透镜天线
US20100033389A1 (en) * 2008-08-07 2010-02-11 Toyota Motor Engineering & Manufacturing North America, Inc. Automotive radar using a metamaterial lens
US20110095953A1 (en) * 2009-10-22 2011-04-28 Lockheed Martin Corporation Metamaterial lens feed for multiple beam antennas
CN102110890A (zh) * 2011-02-11 2011-06-29 中国科学院光电技术研究所 一种基于非均匀介质的高增益喇叭天线

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002073740A1 (en) * 2001-03-12 2002-09-19 Wildblue Communications, Inc. Multi-band antenna for bundled broadband satellite internet access and dbs television service
US20090201572A1 (en) * 2008-02-07 2009-08-13 Toyota Motor Engineering & Manufacturing North America, Inc. Metamaterial gradient index lens
US20100033389A1 (en) * 2008-08-07 2010-02-11 Toyota Motor Engineering & Manufacturing North America, Inc. Automotive radar using a metamaterial lens
CN101587990A (zh) * 2009-07-01 2009-11-25 东南大学 基于人工电磁材料的宽带圆柱形透镜天线
US20110095953A1 (en) * 2009-10-22 2011-04-28 Lockheed Martin Corporation Metamaterial lens feed for multiple beam antennas
CN102110890A (zh) * 2011-02-11 2011-06-29 中国科学院光电技术研究所 一种基于非均匀介质的高增益喇叭天线

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112147588A (zh) * 2020-10-14 2020-12-29 中国电波传播研究所（中国电子科技集团公司第二十二研究所） 一种不对称的雷达照射面积快速计算方法

Similar Documents

Publication Publication Date Title
WO2013013465A1 (zh) 后馈式雷达天线
CN102480024B (zh) 一种后馈式雷达天线
WO2014019524A1 (zh) 一种卡塞格伦型超材料天线
CN102904044B (zh) 一种后馈式雷达天线
CN102480031B (zh) 一种后馈式雷达天线
CN102480025B (zh) 一种前馈式雷达天线
WO2013013462A1 (zh) 一种前馈式微波天线
CN103036067A (zh) 一种雷达天线
CN102480032B (zh) 一种偏馈式雷达天线
WO2012155475A1 (zh) 电磁波分束器
WO2013013468A1 (zh) 偏馈式雷达天线
CN103036064A (zh) 一种卡塞格伦型超材料天线
CN102480029B (zh) 一种偏馈式雷达天线
CN102800975B (zh) 一种基站天线
WO2013013466A1 (zh) 后馈式雷达天线
WO2013013467A1 (zh) 前馈式雷达天线
CN102790278B (zh) 定向天线
CN102904045B (zh) 一种前馈式雷达天线
WO2013013469A1 (zh) 前馈式雷达天线
CN102480059B (zh) 基于超材料的天线
WO2013013470A1 (zh) 偏馈式雷达天线
CN102480026B (zh) 一种前馈式雷达天线
CN102790276B (zh) 定向天线
WO2013013461A1 (zh) 后馈式微波天线
WO2013029322A1 (zh) 基站天线

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11869773

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11869773

Country of ref document: EP

Kind code of ref document: A1