CN103367930B - Mobile communications antenna - Google Patents

Abstract

The invention discloses a mobile communications antenna. The antenna comprises a plurality of meta-material plates arranged to be parallel to a horizontal plane, and a plurality of feed sources, wherein the plurality of meta-material plates are disposed at the same horizontal plane, the meta-material plates are corresponding to the feed sources respectively, each meta-material plate comprise a core layer and a reflection layer arranged on the surface of one side of the core layer, the core layer comprises a core layer lamella or a plurality of same core layer lamellas, each core layer lamella comprises a sheet-like first substrate and a plurality of first artificial microstructures arranged on the first substrate, and the plurality of meta-material plates have the same refractive index distribution rule. The refractive index distribution of the meta-material plates is designed in an accurate manner so that plane waves at specific angles may gather at the feed sources through the meat-material plates. The mobile communications antenna provided by the invention adopts the sheet-like meta-material plates to replace a traditional parabolic antenna so that the manufacture and processing are easier and the cost is lower.

Description

Communication-in-motion antenna

Technical Field

The invention relates to the field of communication, in particular to a communication-in-motion antenna.

Background

The communication in motion is short for a mobile satellite ground station communication system. Through the communication-in-motion system, mobile carriers such as vehicles, ships, airplanes and the like can track platforms such as satellites and the like in real time in the motion process, and multimedia information such as voice, data, images and the like can be uninterruptedly transmitted, so that the requirements of various military and civil emergency communication and multimedia communication under mobile conditions can be met. The satellite communication system well solves the problem that various moving carriers such as vehicles, ships and the like continuously transmit multimedia information such as voice, data, high-definition dynamic video images, faxes and the like in real time through a geostationary satellite in motion, is a major breakthrough in the communication field, is an application field with vigorous and rapid development in the current satellite communication field, and has very wide development prospects in both military and civil fields.

As an important component of the communication-in-motion system, the communication-in-motion antenna is responsible for receiving and/or transmitting communication signals, and the traditional communication-in-motion antenna generally adopts a parabolic antenna.

However, since the curved surface of the reflecting surface of the parabolic antenna is difficult to process and has high precision requirement, the manufacturing is troublesome and the cost is high.

Disclosure of Invention

The invention aims to solve the technical problems that the traditional communication-in-motion antenna is difficult to process and high in cost, and provides the communication-in-motion antenna which is simple to process and low in manufacturing cost.

The technical scheme adopted by the invention for solving the technical problems is as follows: a communication-in-motion antenna comprises a plurality of metamaterial flat plates arranged in parallel with a horizontal plane and a plurality of feed sources arranged above the plurality of metamaterial flat plates, wherein the plurality of metamaterial flat plates are positioned on the same horizontal plane, each metamaterial flat plate corresponds to one feed source, each metamaterial flat plate comprises a core layer and a reflecting layer arranged on one side surface of the core layer, the core layer comprises a core layer sheet layer or a plurality of same core layer sheet layers, each core layer sheet layer comprises a first sheet-shaped base material and a plurality of first artificial microstructures arranged on the first base material, the plurality of metamaterial flat plates have the same refractive index distribution law, the upper surface of the core layer of any metamaterial flat plate is taken as an xy plane, the projection of the feed source corresponding to the metamaterial flat plate on the plane of the upper surface of the core layer is taken as a coordinate origin o, establishing a two-dimensional coordinate system of xoy, the refractive index of any point (x, y) of the core layer satisfies the following formula:

s＝y_o×cosγ+z_o×sinγ；

wherein,

n_(x,y)represents any of the core layer sheetsRefractive index values for points (x, y);

z_orepresenting the vertical distance from the corresponding feed source to the upper surface of the metamaterial flat plate;

y_oa y coordinate value indicating an intersection point of the edge of the upper surface of the core layer with the positive direction of the y axis;

gamma represents the elevation angle of the satellite to be communicated;

n_maxrepresenting the maximum value of the refractive index of the core layer sheet layer of the metamaterial flat plate;

n_minrepresenting the minimum value of the refractive index of the core layer sheet layer of the metamaterial flat plate;

λ represents the wavelength of an electromagnetic wave having a frequency of the antenna center frequency;

floor denotes rounding down.

Further, the thickness of the core layer is Dh, 2Dh ═ D.

Further, the first base material comprises a first sheet-shaped front substrate and a first sheet-shaped rear substrate, the plurality of first artificial microstructures are clamped between the first front substrate and the first sheet-shaped rear substrate, the thickness of the core layer sheet layer is 0.21-2.5mm, the thickness of the first front substrate is 0.1-1mm, the thickness of the first rear substrate is 0.1-1mm, and the thickness of the plurality of first artificial microstructures is 0.01-0.5 mm.

Further, each metamaterial flat plate also comprises an impedance matching layer arranged on the other side surface of the core layer of the metamaterial flat plate, the impedance matching layer comprises an impedance matching layer sheet layer or a plurality of impedance matching layer sheet layers with the same thickness, the impedance matching layer sheet layer comprises a second substrate in a sheet shape and a plurality of second artificial microstructures arranged on the second substrate, and the refractive index distribution of the one or more impedance matching layer sheet layers satisfies the following formula:

wherein n is_i(r) represents the refractive index value of the position with radius r on the impedance matching layer slice, and the refractive index distribution center of the impedance matching layer slice is the projection of the feed point on the plane of the outer surface of the corresponding impedance matching layer slice;

wherein i represents the number of the impedance matching layer sheet layer, the number of the impedance matching layer sheet layer close to the feed source is m, the numbers are sequentially reduced from the feed source to the core layer, and the number of the impedance matching layer sheet layer close to the core layer is 1;

n is as defined above_max、n_minThe refractive index of the core layer sheet layer is the same as the maximum value and the minimum value of the refractive index of the core layer sheet layer.

Further, each metamaterial flat plate also comprises an impedance matching layer arranged on the other side surface of the core layer of the metamaterial flat plate, the impedance matching layer comprises an impedance matching layer sheet layer or a plurality of impedance matching layer sheet layers with the same thickness, the impedance matching layer sheet layer comprises a second substrate in a sheet shape and a plurality of second artificial microstructures arranged on the second substrate, each impedance matching layer sheet layer has a single refractive index, and the refractive index of one or more impedance matching layer sheet layers satisfies the following formula:

where m represents the total number of impedance matching layers, and i represents the number of impedance matching layer pieces, where the number of impedance matching layer pieces near the core layer is m.

Further, the thickness of the core layer is Dh, the thickness of the impedance matching layer is Dz, and Dz +2Dh is D.

Further, the second base material comprises a second front substrate and a second rear substrate, the second artificial microstructures are clamped between the second front substrate and the second rear substrate, the thickness of the impedance matching layer is 0.21-2.5mm, the thickness of the second front substrate is 0.1-1mm, the thickness of the second rear substrate is 0.1-1mm, and the thickness of the second artificial microstructures is 0.01-0.5 mm.

Furthermore, the first artificial microstructure and the second artificial microstructure are both metal microstructures formed by copper wires or silver wires, and the metal microstructures are respectively attached to the first base material and the second base material through etching, electroplating, drilling, photoetching, electronic etching or ion etching.

Furthermore, the metal microstructure is in a shape of a flat snowflake, the metal microstructure has a first metal line and a second metal line which are vertically and equally divided, the lengths of the first metal line and the second metal line are the same, two ends of the first metal line are connected with two first metal branches with the same length, two ends of the first metal line are connected to the middle points of the two first metal branches, two ends of the second metal line are connected with two second metal branches with the same length, two ends of the second metal line are connected to the middle points of the two second metal branches, and the lengths of the first metal branch and the second metal branch are equal.

Furthermore, two ends of each first metal branch and each second metal branch of the planar snowflake-shaped metal microstructure are also connected with completely identical third metal branches, and the middle points of the corresponding third metal branches are respectively connected with the end points of the first metal branches and the second metal branches.

Furthermore, the first metal wire and the second metal wire of the planar snowflake-shaped metal microstructure are both provided with two bending portions, and the graphs of the planar snowflake-shaped metal microstructure, which rotate by 90 degrees in any direction in the plane of the metal microstructure around the intersection point of the first metal wire and the second metal wire, coincide with the original graph.

Further, the plurality of metamaterial flat plates have the same shape and size, are circumferentially arranged around a fixed shaft, and the fixed shaft is a central shaft of a structure formed by splicing the plurality of metamaterials.

According to the communication-in-motion antenna, through accurately designing the refractive index distribution of the metamaterial flat plate, plane waves at a specific angle can be converged at the feed source after passing through the metamaterial flat plate, the conventional parabolic antenna is replaced by the sheet-shaped metamaterial flat plate, the manufacturing and processing are easier, the cost is lower, and in addition, the overall thickness of the metamaterial flat plate designed according to the design is in the millimeter level, so that the communication-in-motion antenna is lighter in whole and occupies a small space.

Drawings

FIG. 1 is a schematic diagram of the relative positions of a metamaterial plate and a corresponding feed source in one embodiment of the present invention;

FIG. 2 is a schematic perspective view of one metamaterial unit in a core layer sheet of the present invention;

FIG. 3 is a schematic view of the structure of a core layer sheet of the present invention;

FIG. 4 is a schematic diagram of the structure of the impedance matching layer sheet of the present invention;

FIG. 5 is a schematic of a planar snowflake-like metal microstructure of the present invention;

FIG. 6 is a derivative structure of the planar snowflake-like metallic microstructure shown in FIG. 5;

fig. 7 is a modified structure of the planar snowflake-shaped metal microstructure shown in fig. 5.

FIG. 8 is a first stage of the evolution of the topology of a planar snowflake-like metallic microstructure;

FIG. 9 is a second stage of the evolution of the topology of a planar snowflake-like metallic microstructure;

FIG. 10 is a schematic diagram of the relative positions of a flat metamaterial plate and its corresponding feed source in another embodiment of the present invention;

FIG. 11 is a schematic view of the mounting structure of the communication-in-motion antenna on the vehicle;

FIG. 12 is a schematic diagram of two identical square metamaterial plates according to an embodiment of the present invention;

FIG. 13 is a schematic diagram of two identical semicircular metamaterial plates according to one embodiment of the present invention;

FIG. 14 is an assembled schematic view of three identical fan-shaped metamaterial plates according to an embodiment of the present invention;

FIG. 15 is a schematic diagram of four identical square metamaterial panels according to one embodiment of the present invention;

fig. 16 is an assembly diagram of four identical fan-shaped metamaterial flat plates according to an embodiment of the present invention.

Detailed Description

As shown in fig. 1 and fig. 11, the communication-in-motion antenna DZT of the present invention is loaded on a top position of a mobile carrier YDT (e.g., a vehicle, a ship, or an airplane), and includes a plurality of metamaterial flat plates 100 arranged parallel to a horizontal plane and a plurality of feed sources arranged above the plurality of metamaterial flat plates 100, where each metamaterial flat plate 100 corresponds to one feed source, and a position of each metamaterial plate 100 relative to its corresponding feed source is fixed. In the present invention, the feed is a conventional corrugated horn, such as a tuner integrated with the CL11R of the continental electronics.

In addition, as shown in fig. 11, in order to protect the midcom antenna DZT (waterproof, sun-proof, etc.), the exterior of the midcom antenna DZT may be covered with a radome TXZ, such as a hemispherical radome.

As shown in fig. 1 to 4, in one embodiment of the present invention, each flat metamaterial plate 100 includes a core layer 10, a reflective layer 200 disposed on one side surface of the core layer, and an impedance matching layer 20 disposed on the other side surface of the core layer, the core layer 10 includes a core layer sheet 11 or a plurality of core layer sheets 11 having the same thickness and the same refractive index distribution, the core layer sheet includes a sheet-shaped first substrate 13 and a plurality of first artificial microstructures 12 disposed on the first substrate 13, the impedance matching layer 20 includes an impedance matching layer sheet 21 or a plurality of impedance matching layer sheets 21 having the same thickness, and the impedance matching layer sheet 21 includes a sheet-shaped second substrate 23 and a plurality of second artificial microstructures disposed on the second substrate. In the present invention, the reflective layer may be a metal reflective plate having a smooth surface, such as a polished copper plate, an aluminum plate, or an iron plate, or may be a PEC (ideal electrical conductor) reflective surface, or may be a metal coating layer, such as a copper coating layer. Preferably, the plurality of metamaterial flat plates have the same shape and size, and are circumferentially arranged around a fixed axis, which is a central axis of a structure formed by splicing the plurality of metamaterials. The plurality of metamaterial flat plates can be all adjacent to each other or arranged at equal intervals, preferably, the plurality of metamaterial flat plates are all adjacent to each other and are assembled together into a square, round, oval or other flat plate, for example, the plurality of metamaterial flat plates can be two identical square metamaterial flat plates F2 shown in fig. 12, and two square metamaterial flat plates F2 are assembled into a large square flat plate FB 1; or two identical semicircular metamaterial flat plates S2 as shown in fig. 13, wherein the two identical semicircular metamaterial flat plates S2 are spliced into a complete circular flat plate YB 1; or three identical fan-shaped metamaterial flat plates S3 as shown in fig. 14, wherein three fan-shaped metamaterial flat plates S3 are assembled into a complete circular flat plate YB 2; or four identical square metamaterial flat plates F4 shown in FIG. 15, wherein four square metamaterial flat plates F4 are spliced into a large square flat plate FB 2; or four identical fan-shaped metamaterial flat plates S4 shown in fig. 16, wherein four fan-shaped metamaterial flat plates S4 are assembled into a complete circular flat plate YB 3. In this case, the plurality of flat meta-materials may be independent of each other or may be integrally molded. As also shown in fig. 12-16, each metamaterial plate is represented by different cross-hatching for clear and clear representation.

In the invention, the impedance matching layer is used for realizing impedance matching from air to the core layer 10 so as to reduce electromagnetic wave reflection at the joint of the air and the metamaterial, reduce the loss of electromagnetic wave energy and improve the signal intensity of the satellite television.

As shown in fig. 1 and fig. 16 (taking the metamaterial plate S4 at the upper left corner of fig. 16 as an example), in this embodiment of the mobile communication antenna of the present invention, a two-dimensional coordinate system of xoy is established by taking the upper surface of the core layer of one of the metamaterial plates S4 as an xy plane, the angular bisector of a sector as a y axis, a line perpendicular to the y axis and passing through the vertex of the sector as an x axis, and the projection (point o in fig. 1 and fig. 16) of the feed corresponding to the metamaterial plate on the plane of the upper surface of the core layer of the metamaterial plate as a coordinate origin o, so that the refractive index of any point (x, y) of the core layer of the metamaterial plate satisfies the following formula:

s＝y_o×cosγ+z_o×sinγ (2)；

fig. 1 is a cross-sectional view obtained by cutting the metamaterial flat plate and the feed source of the communication-in-motion antenna of the present embodiment on a plane formed by a central axis of the feed source and a geostationary satellite (equivalent to a point) to be communicated, that is, a cross-sectional view obtained by cutting the metamaterial flat plate and the feed source of the communication-in-motion antenna of the present embodiment on a plane formed by a y axis and the central axis of the feed source.

Wherein n is_(x,y)Representing the refractive index value of any point (x, y) of the core layer sheet;

z_orepresenting the vertical distance from the feed source to the upper surface of the metamaterial flat plate; here, the feed source is equivalent to a point source, and a feed point X of the feed source is a point where electromagnetic waves emitted by a satellite to be communicated are focused in the feed source after passing through the metamaterial flat plate; the vertical distance from the feed source to the metamaterial flat plate is the vertical distance from the feed point X to the metamaterial flat plate; the projection of the feed source on the plane of the upper surface of the metamaterial flat plate is the projection o of the feed point X on the plane of the upper surface of the metamaterial flat plate; an included angle between the feed source central axis Z1 and the upper surface of the metamaterial flat plate is theta, in the embodiment, the feed point X is on the feed source central axis Z1, and the distance from the feed source aperture central point to the feed point X is assumed to be ds, so that the convergence effect is optimal by changing two variable parameters of ds and theta (namely, enabling the feed source to scan the optimal position);

y_oa y coordinate value representing an intersection point of the upper surface edge of the core layer of the metamaterial flat plate S4 and the positive direction of the y axis; as shown in FIG. 16, y_oI.e., the length of the OA line segment in the figure (radius of the sector).

Gamma represents the elevation angle of the satellite to be communicated, and the elevation angle gamma is related to the longitude and latitude of the satellite to be communicated and the communication-in-motion antenna;

n_maxrepresents the maximum value of the refractive index of the core layer sheet layer;

n_minrepresents the minimum value of the refractive index of the core layer sheet layer;

λ represents the wavelength of an electromagnetic wave having a frequency of the antenna center frequency;

in this embodiment, the thickness of the core layer is Dh, the thickness of the impedance matching layer is Dz, and Dz +2Dh is D.

floor denotes rounding down;

for example, whenWhen the k is more than or equal to 0 and less than 1, k is 0; when in use(when 1 is larger than or equal to 1 and smaller than 2, k is 1, and so on.

The metamaterial flat plate determined by the formulas (1) to (4) can enable electromagnetic waves emitted by the feed source to be emitted in a plane wave form forming a gamma angle with a horizontal plane after passing through the corresponding metamaterial flat plate; similarly, as shown in fig. 1, the metamaterial flat plate determined by the formulas (1) to (4) can enable electromagnetic waves (which can be regarded as plane waves with an angle γ with the horizontal plane when reaching the ground) emitted by a satellite to be communicated to converge at the feed point X after passing through the metamaterial flat plate.

The structure and refractive index distribution of the other three metamaterial plates S4 in fig. 16 refer to the metamaterial plate S4 at the upper left corner in fig. 16.

The principle of assembling a flat metamaterial plate as shown in fig. 12 to 15 can be similar to the structure shown in fig. 16, and the coordinate system is established as shown in the figure. In fig. 12 to 15, the line OA is a y coordinate value y of an intersection point of the upper surface edge of the meta-material flat plate and the positive direction of the y axis_o. In this embodiment, the upper surface of the meta-material flat plate is the upper surface of the impedance matching layer 20 shown in fig. 1.

When the movable carrier YDT moves, the movable carrier YDT often has motion states of turning, up-and-down floating and the like, the communication between the communication-in-motion antenna and the satellite can be kept uninterrupted through the servo system CF, namely the metamaterial flat plate is parallel to the horizontal plane in any motion state, and meanwhile, the servo system CF can synchronously rotate a plurality of metamaterial flat plates, so that the y-axis direction of the surface of one metamaterial flat plate is always aligned to the position of the synchronous satellite to be communicated. The servo system CF can have a very simple control design for the synchronous control of a plurality of metamaterial flat plates, for example, the plurality of metamaterial flat plates are synchronously rotated, so that the y-axis direction of the surface of the fan-shaped metamaterial flat plate, the angular bisector of which is closest to the projection of the central axis of the feed source on the horizontal plane, is intersected with the central axis of the feed source, namely the smaller the rotation angle of the whole formed by the plurality of metamaterial flat plates is, the more control is facilitated, meanwhile, the response time is short, and the precision is high.

There are many servo systems with the above functions in the prior art, which are not the core of the present invention, and those skilled in the art can easily make a servo system with similar functions by combining the prior art according to the above description, and the detailed description is omitted here.

In this embodiment, as shown in fig. 3, the first base material 13 includes a sheet-shaped first front substrate 131 and a sheet-shaped first rear substrate 132, and the plurality of first artificial microstructures 12 are sandwiched between the first front substrate 131 and the first rear substrate 132. The thickness of the core layer sheet layer is 0.5-2mm, wherein the thickness of the first front substrate is 0.5-1mm, the thickness of the first rear substrate is 0.5-1mm, and the thickness of the plurality of first artificial microstructures is 0.01-0.5 mm. Preferably, the thickness of the core layer sheet layer is 0.543mm, wherein the thickness of each of the first front substrate and the first rear substrate is 0.254mm, and the thickness of each of the plurality of first artificial microstructures is 0.035 mm.

In this embodiment, the refractive index profile of the one or more impedance matching layer sheets satisfies the following formula:

wherein n is_i(r) represents the refractive index value of the radius r on the impedance matching layer sheet, the refractive index distribution center of the impedance matching layer sheet is the projection of the feed point on the plane of the outer surface of the corresponding impedance matching layer sheet, preferably, the connecting line of the refractive index distribution center of the impedance matching layer sheet and the refractive index distribution center of the core layer sheet is vertical to the metamaterial flat plate;

wherein i represents the number of the impedance matching layer sheet layer, the number of the impedance matching layer sheet layer close to the feed source is m, the numbers are sequentially reduced from the feed source to the core layer, and the number of the impedance matching layer sheet layer close to the core layer is 1;

n is as defined above_max、n_minThe refractive index of the core layer sheet layer is the same as the maximum value and the minimum value of the refractive index of the core layer sheet layer respectively;

specifically, for example, if m is 2, the refractive index distribution of the impedance matching layer close to the core layer is as follows:

the refractive index distribution of the impedance matching layer close to the feed source is as follows:

n₂(r)＝n_min；

of course, the impedance matching layer is not limited thereto, and each of the impedance matching layer sheets may have a single refractive index, and the refractive index of the one or more impedance matching layer sheets satisfies the following formula:

where m represents the total number of impedance matching layers, and i represents the number of impedance matching layer pieces, where the number of impedance matching layer pieces near the core layer is m.

Specifically, for example, if m is 2, the refractive index distribution of the impedance matching layer close to the core layer is as follows:

n(2)＝(n_max+n_min)/2；

the refractive index distribution of the impedance matching layer close to the feed source is as follows:

in this embodiment, the second base 23 includes a sheet-shaped second front substrate 231 and a second rear substrate 232, and the plurality of second artificial microstructures are sandwiched between the second front substrate 231 and the second rear substrate 232. The thickness of the impedance matching layer sheet layer is 0.21-2.5mm, wherein the thickness of the first front substrate is 0.1-1mm, the thickness of the first rear substrate is 0.1-1mm, and the thickness of the first artificial microstructures is 0.01-0.5 mm. Preferably, the thickness of the impedance matching layer sheet layer is 0.543mm, the thicknesses of the second front substrate and the second rear substrate are both 0.254mm, and the thicknesses of the plurality of second artificial microstructures are 0.035 mm.

In this embodiment, the first artificial microstructure and the second artificial microstructure are both metal microstructures formed by copper wires or silver wires, and the metal microstructures are respectively attached to the first base material and the second base material by etching, electroplating, drilling, photoetching, electronic etching or ion etching. Preferably, the first artificial microstructure and the second artificial microstructure are both the planar snowflake-shaped metal microstructure shown in fig. 5, and the planar snowflake-shaped metal microstructure is a plurality of metal microstructures with different topographies obtained through topology evolution.

In this embodiment, the core layer sheet layer may be obtained by coating copper on a surface of any one of the first front substrate and the first rear substrate, obtaining a plurality of first metal microstructures by an etching method (the shapes and the arrangement of the plurality of first metal microstructures are obtained by computer simulation in advance), and finally pressing the first front substrate and the first rear substrate together, respectively, to obtain the core layer sheet layer of the present invention, where the pressing method may be direct hot pressing, or may be connection by using a hot melt adhesive, or may be other mechanical connection, such as bolt connection.

Similarly, the impedance matching layer sheet can be obtained by the same method. Then respectively pressing a plurality of core layer sheet layers into a whole to form the core layer of the invention; similarly, a plurality of impedance matching layer sheets are pressed into a whole, so that the impedance matching layer is formed; and (3) integrating the core layer, the impedance matching layer and the reflecting layer to obtain the metamaterial flat plate.

In this embodiment, the first substrate and the second substrate are made of a ceramic material, a polymer material, a ferroelectric material, a ferrite material, a ferromagnetic material, or the like. The polymer material can be selected from F4B composite material, FR-4 composite material, etc.

Fig. 5 is a schematic diagram of a planar snowflake-shaped metal microstructure, where the snowflake-shaped metal microstructure includes a first metal line J1 and a second metal line J2 that are vertically bisected, the lengths of the first metal line J1 and the second metal line J2 are the same, two ends of the first metal line J1 are connected to two first metal branches F1 with the same length, two ends of the first metal line J1 are connected to the middle points of the two first metal branches F1, two ends of the second metal line J2 are connected to two second metal branches F2 with the same length, two ends of the second metal line J2 are connected to the middle points of the two second metal branches F2, and the lengths of the first metal branch F1 and the second metal branch F2 are equal.

Fig. 6 is a derivative structure of the planar snowflake-like metal microstructure shown in fig. 5. The two ends of each first metal branch F1 and each second metal branch F2 are connected with identical third metal branches F3, and the middle points of the corresponding third metal branches F3 are respectively connected with the end points of the first metal branch F1 and the second metal branch F2. By analogy, other forms of metal microstructures can be derived.

Fig. 7 is a modified structure of the planar snowflake-shaped metal microstructure shown in fig. 5, in which the first metal line J1 and the second metal line J2 are not straight lines, but are bent lines, and the first metal line J1 and the second metal line J2 are both provided with two bending portions WZ, but the first metal line J1 and the second metal line J2 are still vertically bisected, so that a pattern of the metal microstructure shown in fig. 7 rotated by 90 degrees in any direction around an axis perpendicular to the intersection point of the first metal line and the second metal line coincides with the original figure by setting the orientation of the bending portions and the relative positions of the bending portions on the first metal line and the second metal line. In addition, other variations are possible, for example, the first metal line J1 and the second metal line J2 are both provided with a plurality of bent portions WZ.

In this embodiment, the core layer sheet layer 11 may be divided into a plurality of metamaterial units D arranged in an array as shown in fig. 2, each metamaterial unit D includes a front substrate unit U, a rear substrate unit V, and a first artificial microstructure 12 disposed between the substrate unit U and the rear substrate unit V, and generally, the length, width, and height of the metamaterial unit D are not greater than one fifth of a wavelength, and preferably, one tenth of a wavelength, so that the size of the metamaterial unit D can be determined according to the operating frequency of the antenna. Fig. 2 is a perspective drawing to show the position of the metamaterial unit D of the first artificial microstructure, as shown in fig. 2, the first artificial microstructure is sandwiched between the substrate unit U and the rear substrate unit V, and the surface thereof is represented by SR.

Known refractive indexWhere μ is the relative permeability and the relative permittivity, and μ is collectively referred to as the electromagnetic parameter. Experiments prove that when electromagnetic waves pass through a dielectric material with non-uniform refractive index, the electromagnetic waves are deflected to the direction with large refractive index. Under the condition that the relative permeability is certain (generally close to 1), the refractive index is only related to the dielectric constant, under the condition that the first base material is selected, the first artificial microstructure only responding to an electric field can be used for realizing any value (within a certain range) of the metamaterial unit refractive index, under the central frequency of the antenna, simulation software such as CST, MATLAB, COMSOL and the like is used for obtaining the condition that the refractive index of the artificial microstructure (such as the planar snowflake metal microstructure shown in figure 5) with a certain specific shape changes along with the change of the topological shape through simulation, namely, corresponding data can be listed, the required core layer 11 with the specific refractive index distribution can be designed, and the refractive index distribution of the impedance matching layer can be obtained in the same way.

In this embodiment, the structural design of the core layer and the sheet layer can be obtained through computer simulation (CST simulation), which is specifically as follows:

(1) an attached substrate (first substrate) of the first metal microstructure is determined. For example, a dielectric substrate having a dielectric constant of 2.25, the material of the dielectric substrate may be FR-4, F4b or PS.

(2) The dimensions of the metamaterial unit cells are determined. The size of the metamaterial unit is obtained by the central frequency of the antenna, the wavelength of the metamaterial unit is obtained by using the frequency, and a value smaller than one fifth of the wavelength is taken as the length CD and the width KD of the metamaterial unit D. For example, corresponding to an antenna center frequency of 11.95G, the metamaterial unit D is a square small plate with a length CD and a width KD of 2.8mm and a thickness HD of 0.543mm as shown in fig. 2.

(3) And determining the material and the topological structure of the metal microstructure. In the invention, the metal microstructure is made of copper, the topological structure of the metal microstructure is a planar snowflake-shaped metal microstructure shown in fig. 5, and the line width W of the metal microstructure is consistent everywhere; the term "topology" as used herein refers to the basic shape of the evolution of the topology.

(4) And determining the topological shape parameters of the metal microstructure. As shown in fig. 5, in the present invention, the topological parameters of the planar snowflake-shaped metal microstructure include a line width W of the metal microstructure, a length a of the first metal line J1, and a length b of the first metal branch F1.

(5) Determining the evolution limitation condition of the topological shape of the metal microstructure. In the invention, the evolution of the topological shape of the metal microstructure is limited by the minimum spacing WL between the metal microstructures (i.e. as shown in fig. 5, the distance between the metal microstructure and the long side or the wide side of the metamaterial unit is WL/2), the line width W of the metal microstructure, and the size of the metamaterial unit; due to the limitation of the processing technology, WL is more than or equal to 0.1mm, and the line width W is also more than or equal to 0.1 mm. When the first simulation is carried out, WL can be 0.1mm, W can be 0.3mm, the length and width of the metamaterial unit are 2.8mm, the thickness of the metamaterial unit is 0.543mm, and at the moment, the topological shape parameters of the metal microstructure only have two variables of a and b. The topology of the metal microstructure can be developed in a manner as shown in fig. 8 to 9, and a continuous refractive index variation range can be obtained corresponding to a specific frequency (for example, 11.95 GHZ).

Specifically, the topological shape evolution of the metal microstructure comprises two stages (the basic shape of the topological shape evolution is the metal microstructure shown in fig. 5):

the first stage is as follows: according to the evolution limiting condition, under the condition that the b value is kept unchanged, the a value is changed from the minimum value to the maximum value, and the metal microstructures in the evolution process are all in a cross shape (except when the a value is the minimum value). In this embodiment, the minimum value of a is 0.3mm (line width W), and the maximum value of a is (CD-WL). Therefore, in the first stage, the topological shape of the metal microstructure evolves as shown in fig. 8, namely from a square JX1 with a side length W, to a maximum cross-shaped topological shape JD 1. In the first stage, as the topological shape of the metal microstructure evolves, the refractive index of the metamaterial unit corresponding to the metal microstructure continuously increases (corresponding to a specific frequency of the antenna).

And a second stage: according to the evolution limiting condition, when a is increased to the maximum value, a is kept unchanged; at the moment, b is continuously increased from the minimum value to the maximum value, and the metal microstructures in the evolution process are all in a plane snowflake shape. In this example, the minimum value of b is 0.3mm, and the maximum value of b is (CD-WL-2W). Therefore, in the second stage, the topological shape of the metal microstructure evolves as shown in fig. 9, i.e. gradually evolves from the maximum cross-shaped topological shape JD1 to the maximum planar snowflake topological shape JD2, where the maximum planar snowflake topological shape JD2 means that the lengths b of the first metal branch J1 and the second metal branch J2 cannot be elongated any more, otherwise the first metal branch and the second metal branch will intersect. In the second stage, as the topological shape of the metal microstructure evolves, the refractive index of the metamaterial unit corresponding to the metal microstructure continuously increases (corresponding to a specific frequency of the antenna).

Obtaining the variation range of the refractive index of the metamaterial unit through the above evolution if the variation range meets the design requirement (namely the variation range includes n)_min-n_maxRange of (d). If the above evolution yields a range of refractive index variations for the metamaterial unit that does not meet the design requirements, e.g., the maximum is too small, then the WL and W are varied,and re-simulating until obtaining the refractive index change range required by us.

According to the formulas (1) to (4), after a series of metamaterial units obtained by simulation are arranged according to the corresponding refractive indexes (actually, the metamaterial units are arranged on a first base material by a plurality of first artificial microstructures with different topological shapes), the core layer sheet layer can be obtained.

Similarly, the impedance matching layer sheet of the present invention can be obtained according to formulas (5) to (6).

As shown in fig. 10, in another embodiment of the present invention, the metamaterial flat plate 100 does not have an impedance matching layer, in this embodiment, the thickness of the core layer is Dh, and 2Dh ═ D. In this embodiment, the upper surface of the metamaterial flat plate is the upper surface of the core layer 10 shown in fig. 10. Otherwise, the same as the above embodiment.

Similarly, fig. 10 is a cross-sectional view obtained by cutting the metamaterial flat plate and the feed source in the mobile antenna of the present embodiment on a plane formed by the central axis of the feed source and a geostationary satellite (equivalently, a point) to be communicated, that is, a cross-sectional view obtained by cutting the metamaterial flat plate and the feed source in the mobile antenna of the present embodiment on a plane formed by the y axis and the central axis of the feed source.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (12)

1. A communication-in-motion antenna is characterized by comprising a plurality of metamaterial flat plates arranged in parallel with a horizontal plane and a plurality of feed sources arranged above the plurality of metamaterial flat plates, wherein the plurality of metamaterial flat plates are positioned on the same horizontal plane, each metamaterial flat plate corresponds to one feed source, each metamaterial flat plate comprises a core layer and a reflecting layer arranged on the surface of one side of the core layer, the core layer comprises a core layer sheet layer or a plurality of core layer sheets with the same refractive index distribution and thickness, each core layer sheet layer comprises a first sheet-shaped base material and a plurality of first artificial microstructures arranged on the first base material, the plurality of metamaterial flat plates have the same refractive index distribution rule, the upper surface of the core layer sheet layer of any metamaterial flat plate is taken as an xy plane, the projection of the feed source corresponding to the metamaterial flat plate on the plane of the upper surface of the core layer sheet layer is taken as a coordinate origin o, establishing a two-dimensional coordinate system of xoy, the refractive index of any point (x, y) of the core layer satisfies the following formula:

$n_{(x,y)}=n_{max}-\frac{\sqrt{x^2+y^2+{z_o}^2}+(y_o-y)\×cos\mathrm{\γ}-(s+k\mathrm{\λ})}{D};$

s＝y_o×cosγ+z_o×sinγ；

$k=floor\left\{\frac{\sqrt{x^2+y^2+{z_o}^2}+(y_o-y)\×cos\mathrm{\γ}-(y_o\×cos\mathrm{\γ}+z_o\×sin\mathrm{\γ})}{\mathrm{\λ}}\right\};$

$D=\frac{\mathrm{\λ}}{n_{max}-n_{min}};$

wherein,

n_(x,y)representing a refractive index value at any point (x, y) of the core layer sheet;

z_orepresenting the vertical distance from the corresponding feed source to the upper surface of the metamaterial flat plate;

y_oa y coordinate value indicating an intersection point of the edge of the upper surface of the core layer with the positive direction of the y axis;

gamma represents the elevation angle of the satellite to be communicated;

n_maxrepresenting the maximum value of the refractive index of the core layer sheet layer of the metamaterial flat plate;

n_minrepresenting the minimum value of the refractive index of the core layer sheet layer of the metamaterial flat plate;

λ represents the wavelength of an electromagnetic wave having a frequency of the antenna center frequency;

floor denotes rounding down.

2. The mobile communication antenna according to claim 1, wherein the thickness of the core layer is Dh, and 2Dh is D.

3. The mobile communication antenna according to claim 1, wherein the first base material comprises a first front substrate and a first rear substrate in a sheet shape, the plurality of first artificial microstructures are sandwiched between the first front substrate and the first rear substrate, the thickness of the core layer is 0.21-2.5mm, the thickness of the first front substrate is 0.1-1mm, the thickness of the first rear substrate is 0.1-1mm, and the thickness of each first artificial microstructure is 0.01-0.5 mm.

4. The communication-in-motion antenna of claim 1, wherein each metamaterial plate further comprises an impedance matching layer disposed on a surface of the core layer close to the side of the feed source, the impedance matching layer comprises one impedance matching layer sheet or a plurality of impedance matching layer sheets with the same thickness, the impedance matching layer sheet comprises a second substrate in a sheet shape and a plurality of second artificial microstructures disposed on the second substrate, and a refractive index distribution of the one or more impedance matching layer sheets satisfies the following formula:

$n_i\left(r\right)={n_{min}}^{\frac{i}{m}}\×n{\left(r\right)}^{\frac{m-i}{m}};$

wherein n is_i(r) represents the refractive index value of the position with radius r on the impedance matching layer slice, and the refractive index distribution center of the impedance matching layer slice is the projection of the feed point on the plane of the outer surface of the corresponding impedance matching layer slice; n (r) represents a refractive index distribution when i is 1;

wherein i represents the number of the impedance matching layer sheet layer, the number of the impedance matching layer sheet layer close to the feed source is m, the numbers are sequentially reduced from the feed source to the core layer, and the number of the impedance matching layer sheet layer close to the core layer is 1.

5. The communication-in-motion antenna of claim 1, wherein each metamaterial plate further comprises an impedance matching layer disposed on the surface of the core layer close to the side of the feed source, the impedance matching layer comprises one impedance matching layer sheet or a plurality of impedance matching layer sheets with the same thickness, the impedance matching layer sheet comprises a second substrate in a sheet shape and a plurality of second artificial microstructures disposed on the second substrate, each impedance matching layer sheet has a single refractive index, and the refractive index of the one or more impedance matching layer sheets satisfies the following formula:

$n\left(i\right)={\left(\right(n_{max}+n_{\min })/2)}^{\frac{i}{m}};$

wherein m represents the total number of the impedance matching layers, i represents the number of the impedance matching layer layers, and the number of the impedance matching layer layers close to the core layer is m; the numbers are sequentially increased from 1 in the direction from the feed source to the core layer; n is as defined above_max、n_minThe refractive index of the core layer sheet layer is the maximum value and the minimum value respectively.

6. The mobile communication antenna according to claim 4 or 5, wherein the thickness of the core layer is Dh, the thickness of the impedance matching layer is Dz, and Dz +2Dh is D.

7. The communication-in-motion antenna according to claim 4 or 5, wherein the second base material comprises a second front substrate and a second rear substrate in a sheet shape, the plurality of second artificial microstructures are sandwiched between the second front substrate and the second rear substrate, the thickness of the impedance matching layer is 0.21-2.5mm, the thickness of the second front substrate is 0.1-1mm, the thickness of the second rear substrate is 0.1-1mm, and the thickness of each second artificial microstructure is 0.01-0.5 mm.

8. The mobile phone of claim 7, wherein the first and second artificial microstructures are metal microstructures formed by copper wires or silver wires, and the metal microstructures are respectively attached to the first and second substrates by etching, electroplating, drilling, photolithography, electronic etching or ion etching.

9. The antenna of claim 8, wherein the metal microstructure is in a shape of a flat snowflake, and has a first metal line and a second metal line that are vertically and equally divided from each other, the lengths of the first metal line and the second metal line are the same, two ends of the first metal line are connected to two first metal branches with the same length, two ends of the first metal line are connected to the middle points of the two first metal branches, two ends of the second metal line are connected to two second metal branches with the same length, two ends of the second metal line are connected to the middle points of the two second metal branches, and the lengths of the first metal branch and the second metal branch are equal.

10. The antenna of claim 9, wherein the two ends of each first metal branch and each second metal branch of the planar snowflake-shaped metal microstructure are further connected with identical third metal branches, and the middle points of the corresponding third metal branches are respectively connected with the end points of the first metal branch and the second metal branch.

11. The antenna of claim 9, wherein the first metal line and the second metal line of the planar snowflake-shaped metal microstructure are each provided with two bending portions, and a pattern of the planar snowflake-shaped metal microstructure rotated by 90 degrees in any direction in a plane of the metal microstructure around an intersection point of the first metal line and the second metal line coincides with an original figure.

12. The mobile communication-in-motion antenna according to claim 1, wherein the plurality of metamaterial flat plates have the same shape and size, and are circumferentially arranged around a fixed axis, and the fixed axis is a central axis of a structure formed by assembling the plurality of metamaterials.