A high-gain dual-polarized dielectric meta-antenna, MIMO antenna and multi-frequency antenna

Abstract

The present application discloses a high-gain dual-polarized dielectric metastructure antenna, a MIMO antenna, and a multi-frequency antenna. The high-gain dual-polarized dielectric metastructure antenna includes a metal reflector; a dual-polarized radiating element, which is placed on the metal reflector; a lens, which is placed on the side of the dual-polarized radiating element away from the metal reflector, and the lens contains a plurality of short conductive tubes separated from each other, the central axis direction of the short conductive tubes is parallel to the central longitudinal axis direction of the lens, and provides the same delay coefficient for any polarized electromagnetic wave propagation parallel to the central longitudinal axis direction of the lens, so that the delay of the lens to the electromagnetic wave is greater than the delay of the electromagnetic wave propagating in other directions. In the present application, the short conductive tubes provide the same delay coefficient for any polarization of the electromagnetic wave parallel to the central longitudinal axis, so that the delay of the lens to the electromagnetic wave propagating along the central longitudinal axis is greater than the delay of the electromagnetic wave propagating in other directions, which can more effectively form a narrow beam and suppress side lobes.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to a high-gain dual-polarization dielectric superstructure antenna, a MIMO antenna and a multi-frequency antenna. Background Art

[0002] Prior art shows that different types of antennas, such as array antennas, horn antennas, dish antennas and lens antennas, can produce narrow beams, but these antennas are large in the plane perpendicular to the beam direction. Therefore, the wind load of such antennas is large and cannot be used in tunnels, especially when high-speed trains pass through tunnels. Antennas for such scenarios must be small in the plane perpendicular to the beam direction, but can be long. Traveling wave antennas with dielectric rods have such a shape, but this antenna is suitable for frequencies above 3GHz, the size of the dielectric rod is small, and the weight of the antenna is acceptable. The most suitable for this application is the Yagi antenna, which has a wire array in front of the radiating element, but can only provide 15dBi gain in 7% of the frequency band. To achieve a gain of 15dBi, a long array containing 30 directors must be precisely manufactured. This is a serious disadvantage of the Yagi antenna, so an array usually contains less than 10 directors to keep the specifications of the manufactured antenna. The Yagi antenna has a gain of 6-8 dBi when operating in the 40% band and a gain of 10-12dBi when operating in the 20% band.

[0003] Therefore, known antennas that can provide high gain are too large, while other known antennas with suitable shapes do not exceed 12dBi gain in the 40% band. Summary of the invention

[0004] In order to overcome at least one of the defects described in the above-mentioned prior art, the present application provides a high-gain dual-polarized dielectric metastructure antenna, which has a relatively small size in a plane perpendicular to the beam direction and a long length to reduce wind load. The antenna can be used as a high-gain antenna to provide mobile communications in tunnels and along high-speed railways.

[0005] A high-gain dual-polarization dielectric metastructure antenna according to an embodiment of the present application includes: a metal reflector; a dual-polarization radiating element, the dual-polarization radiating element is placed on the metal reflector, and the dual-polarization radiating element radiates electromagnetic waves along the central longitudinal axis of the lens; a lens, the lens is placed on a side of the dual-polarization radiating element away from the metal reflector, the lens includes a plurality of short conductive tubes separated from each other by lightweight dielectric materials, wherein the central axis direction of the short conductive tubes is parallel to the central longitudinal axis direction of the lens, the short conductive tubes form a lattice, and provide the same delay coefficient for the propagation of any polarized electromagnetic wave parallel to the central longitudinal axis direction of the lens, so that the delay of the electromagnetic wave by the lens is greater than that of the electromagnetic wave propagating in other directions.

[0006] In the present high-gain dual-polarized dielectric metastructure antenna, a lattice is formed by short conductive tubes to provide the same delay coefficient for any polarization of electromagnetic waves propagating in a direction parallel to the central longitudinal axis of the lens, so that the delay of the lens for electromagnetic waves propagating along the central longitudinal axis of the lens is greater than the delay for electromagnetic waves propagating in other directions, thereby more effectively forming a narrow light beam and suppressing side lobes.

[0007] According to some embodiments of the present application, the shape of the lens is a cylinder.

[0008] According to some embodiments of the present application, a protrusion is provided on at least one end of the lens extending along the central longitudinal axis, wherein: the protrusion is provided in a hemispherical shape; or the protrusion is provided in a truncated cone shape, and the end surface area of ​​the protrusion close to the lens side is larger than the end surface area away from the lens side.

[0009] According to some embodiments of the present application, the shape of the lens is a rod with a triangular or polygonal cross-section.

[0010] According to some embodiments of the present application, a protrusion is extended from at least one end of the lens along the central longitudinal axis, the protrusion is arranged in a prism shape, and the end surface area of ​​the protrusion close to the lens side is larger than the end surface area away from the lens side.

[0011] According to some embodiments of the present application, the lens includes a plurality of conductive tube layers arranged along a central longitudinal axis, each of the conductive tube layers includes a plurality of short conductive tubes separated from each other by lightweight dielectric materials, and lightweight dielectric materials are arranged between adjacent conductive tube layers.

[0012] According to some embodiments of the present application, the short conductive tubes in the conductive tube layer form a polygonal or sunflower-shaped lattice.

[0013] According to some embodiments of the present application, the minimum distance between adjacent short conductive tubes in the same conductive tube layer is defined as H1, and the distance between adjacent conductive tube layers is defined as H2; wherein H2 is greater than H1.

[0014] According to some embodiments of the present application, the conductive tube layer includes a first conductive tube layer and a second conductive tube layer, and the second conductive tube layer is arranged at an end of the first conductive tube layer away from the metal reflective plate and / or an end close to the metal reflective plate; when the second conductive tube layer is arranged at an end of the first conductive tube layer away from the metal reflective plate, the lens is driven to match the free space; when the second conductive tube layer is arranged at an end of the first conductive tube layer close to the metal reflective plate, the lens is driven to match the dual-polarization radiation element.

[0015] According to some embodiments of the present application, the number of the short conductive tubes included in the second conductive tube layer is less than the number of the short conductive tubes included in the first conductive tube layer.

[0016] According to some embodiments of the present application, the shape of the metal reflective plate is circular or polygonal.

[0017] According to some embodiments of the present application, a conductive side plate is further included, and the conductive side plate is arranged on the outer edge of the metal reflective plate.

[0018] According to some embodiments of the present application, a radome is further included, wherein the metal reflector, the dual-polarization radiation element and the lens are all accommodated in the radome.

[0019] Based on the same inventive concept, the present application also proposes a dual-polarization MIMO antenna, comprising the high-gain dual-polarization dielectric metastructure antenna and antenna cover as described above, wherein: at least two of the dual-polarization radiating elements are placed side by side on the metal reflector, and a lens is placed on the side of each dual-polarization radiating element away from the metal reflector, and the metal reflector, the dual-polarization radiating element and the lens are all accommodated in the antenna cover.

[0020] Based on the same inventive concept, the present application also proposes a dual-polarization multi-frequency antenna, including the high-gain dual-polarization dielectric metastructure antenna as described above, wherein: at least two of the dual-polarization radiating elements are placed side by side on the metal reflector, and a lens is placed on the side of each dual-polarization radiating element away from the metal reflector, and at least two of the dual-polarization radiating elements operate in different frequency bands.

[0021] In summary, the high-gain dual-polarized dielectric metastructure antenna provided by the present application has the following technical effects:

[0022] 1) The lattice formed by short conductive tubes provides the same delay coefficient for any polarization of electromagnetic waves propagating in the direction parallel to the central longitudinal axis of the lens, so that the delay of the lens for electromagnetic waves propagating along the central longitudinal axis of the lens is greater than the delay for electromagnetic waves propagating in other directions, which can more effectively form a narrow beam and suppress side lobes, so that the high-gain dual-polarization dielectric metastructure antenna can be used as a high-gain antenna for mobile communications in tunnels and along high-speed railways;

[0023] 2) The distance between adjacent short conductive tubes in the second conductive tube layer is larger than the distance between adjacent short conductive tubes in the first conductive tube layer, so that the impedance of the second conductive tube layer is higher than that of the first conductive tube layer, thereby driving the second conductive tube layer arranged at one end of the first conductive tube layer close to the metal reflector to form a conversion part that matches a lens with free space, and the second conductive tube layer arranged at one end of the first conductive tube layer close to the metal reflector to form a conversion part that matches a lens with a dual-polarization radiation element, so that both the free space and the dual-polarization radiation element can match the lens;

[0024] 3) The distance between adjacent short conductive tubes in the same conductive tube layer is arranged to increase in the direction from the center to the outer contour, so that the lens placed in front of the dual-polarization radiating element can focus the electromagnetic waves propagating perpendicular to the conductive tube layer into the dual-polarization radiating element. Compared with the lens made of homogeneous dielectric material, it can more effectively reflect the electromagnetic waves and allow the electromagnetic waves to penetrate the lens through the outer contour of the multi-layer structure. Therefore, compared with other known antennas, the high-gain dual-polarization dielectric metastructure antenna containing a lens of such a layer structure has less interference with other nearby dual-polarization antennas. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic structural diagram of a high-gain dual-polarized dielectric metastructure antenna according to the first embodiment of the present application;

[0026] Figure 2 This is a schematic diagram of the structure of a cylindrical lens in this application;

[0027] Figure 3a A schematic diagram of the structure of a lattice formed by short conductive tubes in the present application;

[0028] Figure 3b It is another structural schematic diagram of the lattice formed by the short conductive tubes in the present application;

[0029] Figure 3c It is another structural schematic diagram of the lattice formed by the short conductive tubes in the present application;

[0030] Figure 4 Schematic diagram of the distribution of short conductive tubes in the layer structure in this application;

[0031] Figure 5a This is a schematic structural diagram of a lens having a hemispherical convex portion in the present application;

[0032] Figure 5b This is a schematic diagram of the structure of a lens having hemispherical protrusions at both ends in the present application;

[0033] Figure 5c It is a schematic structural diagram of a lens with an elliptical cross section in the present application;

[0034] Figure 5d This is a schematic structural diagram of a lens having a prism-shaped protrusion in the present application;

[0035] Figure 5e It is a schematic structural diagram of a lens having a truncated cone-shaped protrusion in the present application;

[0036] Figure 6 This is a schematic structural diagram of a high-gain dual-polarized dielectric metastructure antenna according to a second embodiment of the present application;

[0037] Figure 7 is a schematic structural diagram of a rod-shaped lens with a square cross section in the present application;

[0038] Figure 8 This is a schematic diagram of the structure of the dual-polarized MIMO antenna in this application;

[0039] Fig. 9 This is a schematic diagram of the structure of the dual-polarization multi-frequency antenna in this application.

[0040] The meanings of the reference numerals are as follows:

[0041] 1. Lens; 2. Dual-polarization radiation element; 3. Metal reflector; 4. Conductive side plate; 5. Antenna cover; 6. Coaxial cable; 7. Short conductive tube; 8. Conductive tube layer; 81 first conductive tube layer; 82, second conductive tube layer. DETAILED DESCRIPTION

[0042] For better understanding and implementation, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0043] In the description of the present application, it should be noted that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0045] In the present application, a high-gain dual-polarization dielectric metastructure antenna includes a dual-polarization radiating element 2 placed on a metal reflector 3 and a lens 1 placed in front of the dual-polarization radiating element 2, the dual-polarization radiating element 2 radiates electromagnetic waves along the central longitudinal axis of the lens 1, and the lens 1 includes a plurality of short conductive tubes 7 separated from each other by foam dielectric materials. The central axis direction of the short conductive tubes 7 is parallel to the central longitudinal axis direction of the lens 1. The short conductive tubes 7 form a lattice, providing the same delay coefficient for any polarization of electromagnetic waves propagating parallel to the central longitudinal axis direction of the lens 1. The lens 1 has anisotropic characteristics, and the lens 1 can delay the propagation of electromagnetic waves in the direction parallel to the central longitudinal axis of the lens more than the propagation of electromagnetic waves in other directions.

[0046] Optionally, the lens 1 includes a plurality of conductive tube layers 8 arranged along the central longitudinal axis, each conductive tube layer 8 includes a plurality of short conductive tubes 7 separated from each other by a lightweight dielectric material; preferably, the lightweight dielectric material is a foam dielectric material. The short conductive tubes 7 arranged in the same layer form a lattice, which provides the same delay coefficient for any polarization of electromagnetic waves propagating perpendicular to the layer. The lens 1 has an isotropic property for such electromagnetic waves, and the high-gain dual-polarization dielectric metastructure antenna forms equal beams for two orthogonal polarizations. For example, the short conductive tubes 7 forming a square, hexagonal or sunflower lattice provide the lens 1 with an isotropic property. Specifically, the delay coefficient of such artificial material depends on the distance between the short conductive tubes 7. The distance between the short conductive tubes 7 arranged on the same conductive tube layer 8 can be increased in the direction of the outer contour of the conductive tube layer 8 to form a conductive tube layer 8 with an uneven dielectric constant. This stacking of layers is like a dielectric lens 1, which effectively focuses electromagnetic waves in a direction perpendicular to the conductive tube layer 8 for propagation.

[0047] When the distance between adjacent short conductive tubes 7 disposed in the same conductive tube layer 8 is smaller than the distance between adjacent conductive tube layers 8, the lens 1 has anisotropic characteristics and delays electromagnetic waves propagating in the direction of the central longitudinal axis of the lens 1 more than electromagnetic waves propagating in other directions. Therefore, the lens including the short conductive tubes 7 forms a narrow light beam and suppresses side lobes more effectively than the lens 1 made of isotropic uniform dielectric material.

[0048] Preferably, the conductive tube layer 8 includes a first conductive tube layer 81 and a second conductive tube layer 82 . Optionally, at least one layer of second conductive tubes is arranged in layers at one end of the first conductive tube layer 81 away from the metal reflector 3, and the second conductive tube layer 82 is used to form a transformation cross-section that matches the lens 1 with the free space; optionally, at least one layer of second conductive tubes is arranged at one end of the first conductive tube layer 81 close to the metal reflector 3, and the second conductive tube layer 82 is used to form a transformation cross-section that matches the lens 1 with the dual-polarization radiation element 2; specifically, the number of short conductive tubes 7 in the second conductive tube layer 82 is less than the number of short conductive tubes 7 in the first conductive tube layer 81, so that the second conductive tube layer 82 at the end away from the metal reflector 3 has a smaller impedance than the free space and a higher impedance than the first conductive tube layer 81, so that the second conductive tube layer 82 forms a transformation cross-section that matches the lens 1 with the free space, and at the same time drives the second conductive tube layer 82 close to the metal reflector 3 to match the dual-polarization radiation element 2, so that the second conductive tube layer 82 forms a transformation cross-section that matches the lens 1 with the dual-polarization radiation element 2.

[0049] The dual-polarized radiating element 2 can be a crossed dipole or a patch. It is also possible to use four folded dipoles as a dual-polarized radiating element 2 and feed it from a common balun balancer. For antennas operating at frequencies above 6 GHz, a small horn antenna or a crossed Vivaldi antenna can be used as the dual-polarized radiating element 2.

[0050] Optionally, the shape of the metal reflector 3 can be a circle or a triangle, quadrilateral, square, hexagon or other polygon. A conductive side plate 4 can be provided on the outer edge of the metal reflector 3 to reduce the radiation from the back. Multiple high-gain dual-polarized dielectric meta-antennas can be placed side by side on the metal reflector 3 and covered by a common antenna cover 5. The high-gain dual-polarized dielectric meta-antennas arranged side by side can operate in different frequency bands. The delay of the lens 1 to electromagnetic waves propagating along the central longitudinal axis of the lens 1 is greater than the delay to electromagnetic waves propagating in other directions, thereby reducing the reflection of electromagnetic waves radiated by the adjacent antennas and reducing interference between the side-by-side antennas. Therefore, the high-gain dual-polarized dielectric meta-antenna of the present invention has advantages when used in 5G wireless communications using a multiple-input multiple-output system and multiple frequency bands.

[0051] In the present application, the first embodiment of a high gain dual polarized dielectric metastructure antenna is shown in FIG. Figure 1In the figure, the cylindrical lens 1 is located on the side of the dual-polarization radiation element 2 away from the circular metal reflector 3, and the dual-polarization radiation element 2 is in a cross-dipole shape and is placed on the circular metal reflector 3 with a conductive side plate 4. The radome 5 covers all parts of the antenna, that is, the circular metal reflector 3, the dual-polarization radiation element 2 and the lens 1 are all accommodated in the radome 5, but does not include the coaxial cable 6 connected to the dual-polarization radiation element 2.

[0052] See also Figure 2 The lens 1 is composed of a plurality of conductive tube layers 8 arranged along the central longitudinal axis of the lens 1. The short conductive tubes 7 are arranged in the conductive tube layers 8 and separated from each other by a foam dielectric material. The axis direction of the short conductive tubes 7 is perpendicular to the conductive tube layers 8. The adjacent conductive tube layers 8 are separated by a foam dielectric layer, which is made of a foam dielectric material. Figure 2 The foam dielectric layer separating each conductive tube layer 8 is not shown. The short conductive tubes 7 arranged in the conductive tube layer 8 form a Figure 3a The square lattice shown has isotropic properties and has the same delay coefficient for any polarized electromagnetic waves propagating in a direction perpendicular to the conductive tube segments 8. Therefore, the antenna according to the present application forms equal beams for two orthogonal polarizations and provides a low level of cross polarization.

[0053] Optionally, the minimum distance between adjacent short conductive tubes 7 in the same conductive tube layer is defined as H1, and the distance between adjacent conductive tube layers is defined as H2; wherein H2 is greater than H1. Preferably, the minimum distance between adjacent short conductive tubes 7 is the distance between the edges of the short conductive tubes 7, so that the minimum distance between adjacent short conductive tubes 7 on any conductive tube layer 8 is smaller than the distance between adjacent conductive tube layers 8, and thus the delay of the lens 1 to electromagnetic waves propagating along the central longitudinal axis of the lens 1 is greater than the delay of electromagnetic waves propagating in other directions. Due to this anisotropy, the lens 1 can more effectively form a narrow beam and suppress side lobes compared to a lens 1 made of isotropic dielectric material.

[0054] Preferably, the conductive tube layer 8 includes a first conductive tube layer 81 and a second conductive tube layer 82, and the second conductive tube layer 82 is arranged at one end of the first conductive tube layer 81 away from the metal reflector 3 and / or at one end close to the metal reflector 3; when the second conductive tube layer 82 is arranged at one end of the first conductive tube layer 81 away from the metal reflector 3, the lens 1 is driven to match with the free space; when the second conductive tube layer 82 is arranged at one end of the first conductive tube layer 81 close to the metal reflector 3, the lens 1 is driven to match with the dual-polarization radiation element 2. Optionally, the number of the second conductive tube layer 82 is at least one layer. Preferably, the second conductive tube layer 82 can be arranged only at the end of the first conductive tube layer 81 away from the metal reflector 3, forming a conversion part that matches the lens 1 with the free space, driving the lens 1 to match the free space; preferably, the second conductive tube layer 82 can be arranged only at the end of the first conductive tube layer 81 close to the metal reflector 3, forming a conversion part that matches the lens 1 and the dual-polarization radiation element 2, driving the lens 1 to match the dual-polarization radiation element 2; preferably, at least one layer of the second conductive tube layer 82 is arranged at the end of the first conductive tube layer 81 away from the metal reflector, and at the same time, at least one layer of the second conductive tube layer 82 is also arranged at the end of the first conductive tube layer 81 close to the metal reflector 3, so that both the free space and the dual-polarization radiation element 2 can match the lens 1.

[0055] Preferably, the number of short conductive tubes 7 included in the second conductive tube layer 82 is less than the number of short conductive tubes 7 included in the first conductive tube layer 81. Specifically, the impedance of each layer depends on the density of the short conductive tubes 7 in the layer. The distance between adjacent short conductive tubes 7 in the second conductive tube layer 82 is greater than the distance between adjacent short conductive tubes 7 in the first conductive tube layer 81, so the impedance of the second conductive tube layer 82 is higher than that of the first conductive tube layer 81. Therefore, when the second conductive tube layer 82 is arranged at one end of the first conductive tube layer 81 close to the metal reflector 3, a conversion part that matches the lens 1 and the dual-polarization radiation element 2 can be formed, driving the lens 1 to match the dual-polarization radiation element 2. When the second conductive tube layer 82 is arranged at one end of the first conductive tube layer 81 close to the metal reflector 3, a conversion part that matches the lens 1 and the dual-polarization radiation element 2 can be formed, driving the lens 1 to match the dual-polarization radiation element 2. Therefore, the dual-polarization antenna of the present application is very compatible with the feeding coaxial cable 6.

[0056] Figure 3b The hexagonal lattice shown and Figure 3c The sunflower lattice shown also provides isotropic properties for electromagnetic waves propagating in a direction perpendicular to the first conductive tube layer 81, and can be used in other embodiments of the present application.

[0057] See also Figure 4As shown, the distance between adjacent short conductive tubes 7 is arranged to increase in the direction from the center of the conductive tube layer 8 to the outer contour. The conductive tube layer 8 mentioned here can be any one or more of the first conductive tube layer 81 and the second conductive tube layer 82. Specifically, when the distance between adjacent short conductive tubes 7 increases in the direction of the outer contour of the conductive tube layer 8, the delay coefficient of the conductive tube layer 8 will decrease toward the outer contour. Therefore, this conductive tube layer 8 is like a thin focusing lens. The lens 1 placed in front of the dual-polarization radiation element 2 can focus the electromagnetic waves propagating perpendicular to the direction of the conductive tube layer 8 into the dual-polarization radiation element 2. When the length of this lens 1 is greater than its diameter, the propagating electromagnetic waves will begin to diffuse on its surface. Therefore, the long lens 1 has the characteristics of a focusing lens 1, and at the same time acts as a dielectric to generate traveling waves. More importantly, Figure 4 The short conductive tubes 7 shown form a multi-layer structure in each conductive tube layer 8, which can more effectively reflect electromagnetic waves than a lens 1 made of a homogeneous dielectric material, allowing the electromagnetic waves to penetrate the lens 1 through the outer contour of the multi-layer structure. Therefore, compared with other known antennas, the high-gain dual-polarization dielectric meta-antenna containing a lens 1 with such a layer structure has less interference with other nearby dual-polarization antennas.

[0058] Furthermore, lenses 1 of different shapes may be used in other embodiments of the present application. Preferably, at least one end of the lens 1 in the direction of the central longitudinal axis is provided with a protrusion, wherein: the protrusion is provided in a hemispherical shape; or the protrusion is provided in a truncated cone shape, and the end surface area of ​​the protrusion close to the lens 1 is larger than the end surface area away from the lens 1. For details, see Figure 5a As shown, the lens 1 has a hemispherical protrusion at one end; Figure 5b As shown, the lens 1 has a structure with hemispherical protrusions at both ends; Figure 5c As shown, the lens 1 is an elliptical structure in cross section along the central longitudinal axis direction; Figure 5d As shown, the lens 1 is a square rod, one end of which is provided with a convex portion, the convex portion is arranged in a prism shape, and the end surface area of ​​the convex portion close to the lens 1 side is larger than the end surface area away from the lens 1 side, see Figure 5e As shown, the lens 1 is cylindrical, and a protrusion is provided at one end thereof, the protrusion is provided in a truncated cone shape, and the end surface area of ​​the protrusion close to the lens 1 is larger than the end surface area away from the lens 1. The selection of the shape of the lens 1 depends on the specifications of the high-gain dual-polarization dielectric meta-antenna.

[0059] In this application, a second embodiment of a high gain dual polarized dielectric metastructure antenna is shown in a schematic side view. Figure 6In the figure, the lens 1 is a rod-shaped antenna with a square cross-section, which is placed above a dual-polarization radiating element 2 in the shape of a folded dipole fed by a common counterpoise. The dual-polarization radiating element 2 is located on a square metal reflector 3 with a conductive side plate 4. The radome 5 covers all parts of the antenna, that is, the circular metal reflector 3, the dual-polarization radiating element 2 and the lens 1 are all contained in the radome 5, but does not include a feeding coaxial cable 6 connected to the dual-polarization radiating element 2.

[0060] See also Figure 7 The lens 1 is composed of a plurality of conductive tube layers 8 along the central longitudinal axis. Short conductive tubes 7 are distributed in the conductive tube layers 8 and are separated from each other by a foam dielectric material. Figure 7 The foam dielectric layer separating each conductive tube layer 8 is not shown. The short conductive tubes 7 are arranged in the conductive tube layers 8 to form a Figure 4 The non-homogeneous lattice shown has isotropic properties and has the same delay coefficient for any polarized electromagnetic waves propagating perpendicularly to the conductive tube layer 8. The delay coefficient of the conductive tube layer 8 decreases toward the outer contour. Therefore, the conductive tube layer 8 is like a thin focusing lens. The conductive tube layer 8 located in front of the dual-polarization radiation element 2 focuses the electromagnetic waves perpendicular to the propagation direction of the conductive tube layer 8 into the dual-polarization radiation element 2. Therefore, the lens 1 has the characteristics of a focusing lens 1 and simultaneously generates traveling waves as a dielectric. Compared with the lens 1 made of homogeneous dielectric material, the lens 1 composed of each conductive tube layer 8 can more effectively reflect the electromagnetic waves penetrating the lens 1 through the outer contour of these conductive tube layers 8.

[0061] Preferably, the distance between adjacent short conductive tubes 7 arranged on the conductive tube layer 8 is smaller than the distance between adjacent conductive tube layers 8, so that the lens 1 has anisotropic characteristics, and the electromagnetic waves propagating along the central longitudinal axis direction of the lens 1 have a longer delay time than the electromagnetic waves propagating along other directions. Due to this characteristic, the lens 1 can more effectively form a narrow beam and suppress side lobes compared with a lens made of isotropic dielectric materials.

[0062] Preferably, at least one second conductive tube layer 82 is provided at one end of the lens 1 away from the metal reflector 3, and at least one second conductive tube layer 82 is also provided at one end of the lens 1 close to the metal reflector 3, and the number of short conductive tubes 7 in the second conductive tube layers 82 at both ends is less than the number of short conductive tubes 7 in the first conductive tube layer 81 in the middle. The minimum distance between two adjacent short conductive tubes 7 in the second conductive tube layer 82 is greater than the minimum distance between two adjacent short conductive tubes 7 in the first conductive tube layer 81, so the impedance of the second conductive tube layer 82 is higher than that of the first conductive tube layer 81. The second conductive tube layer 82 at one end away from the metal reflector 3 forms a conversion part with free space that matches the lens 1, and the second conductive tube layer 82 at one end close to the metal reflector 3 forms a conversion part that matches the lens 1 and the dual-polarization radiation element 2. Therefore, the dual-polarization antenna of the present application is very compatible with the feeding coaxial cable 6.

[0063] The third embodiment of the present application includes a dual-polarization MIMO antenna. The dual-polarization MIMO antenna includes the high-gain dual-polarization dielectric metastructure antenna and the antenna cover 5 as described above, wherein: at least two dual-polarization radiating elements 2 are placed side by side on the metal reflector 3, and a lens 1 is placed on the side of each dual-polarization radiating element 2 away from the metal reflector 3, and the metal reflector 3, the dual-polarization radiating element 2 and the lens 1 are all accommodated in the antenna cover 5. Preferably, refer to Figure 8 The dual-polarized MIMO antenna comprises three high-gain dual-polarized dielectric meta-antennas, specifically, three cylindrical lenses 1 placed side by side, and three dual-polarized radiating elements 2 are placed on a common metal reflector 3, wherein the metal reflector 3, the dual-polarized radiating element 2 and the lens 1 are covered by a common antenna cover 5, and optionally, the dual-polarized radiating element 2 is in the shape of a folded dipole and is fed through a common balun balancer.

[0064] Further, the three cylindrical lenses 1 are all composed of a plurality of conductive tube layers 8, wherein the conductive tube layer 8 mentioned here can be composed of a first conductive tube layer 81 alone or a first conductive tube layer 81 and a second conductive tube layer 82. In the conductive tube layer 8, the distance between adjacent short conductive tubes 7 is set to increase in a direction from the center of the conductive tube layer 8 to the outer contour, see Figure 4 As shown, the impedance of the lens layer increases toward its outer contour and matches the outer contour of the free space. Therefore, the three cylindrical lenses 1 in this embodiment reflect less electromagnetic waves radiated by the antenna next to them and distort their radiation patterns less than the antenna including the lens made of homogeneous dielectric material.

[0065] The fourth embodiment of the present application includes a dual-polarization multi-frequency antenna, which includes the high-gain dual-polarization dielectric metastructure antenna as described above, wherein: at least two dual-polarization radiating elements 2 are placed side by side on a metal reflector 3, a lens 1 is placed on a side of each dual-polarization radiating element 2 away from the metal reflector 3, and at least two dual-polarization radiating elements 2 operate in different frequency bands. Fig. 9 , the radiation bands of the two dual-polarized radiation elements 2 are 1.7-2.69 GHz and 3.3-4.2 GHz respectively, and they are placed side by side on a common metal reflector 3 and covered by a common antenna cover 5. Among them, the lens 1 of the antenna working in the higher frequency band is longer than the lens 1 of the antenna working in the lower frequency band, so a cylinder made of foam dielectric material is placed between the shorter lens 1 and the antenna cover 5 to fix the position of the lens 1.

[0066] Furthermore, both lenses 1 are composed of a plurality of conductive tube layers 8, wherein the conductive tube layer 8 mentioned here can be composed of a first conductive tube layer 81 alone or a first conductive tube layer 81 and a second conductive tube layer 82. In the conductive tube layer 8, the distance between adjacent short conductive tubes 7 is set to increase in a direction from the center of the conductive tube layer 8 to the outer contour, see Figure 4 As shown, as its outer contour increases, the impedance of each layer increases and matches the outer contour of the free space. Compared with the lens 1 made of a homogeneous dielectric material, the two lenses 1 reflect the electromagnetic waves radiated by the next antenna less weakly. Therefore, compared with the parallel lens antenna made of the existing uniform dielectric material, the two antennas in this embodiment have a smaller degree of deformation of the directional patterns with respect to each other.

[0067] The technical means disclosed in the present application are not limited to the technical means disclosed in the above-mentioned implementation methods, but also include technical solutions composed of any combination of the above technical features. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of this application, and these improvements and modifications are also regarded as the protection scope of this application.

Claims

1. A high-gain dual-polarized dielectric metastructure antenna, characterized in that: include: Metal reflective panels; A dual-polarization radiation element, which is placed on the metal reflector and radiates electromagnetic waves along the central longitudinal axis of the lens; A lens, wherein the lens is placed on a side of the dual-polarized radiation element away from the metal reflector, and the lens comprises a plurality of short conductive tubes separated from each other by a lightweight dielectric material, wherein the central axis direction of the short conductive tubes is parallel to the central longitudinal axis direction of the lens, and each of the short conductive tubes forms a lattice, providing the same delay coefficient for the propagation of any polarized electromagnetic wave parallel to the central longitudinal axis direction of the lens, so that the delay of the electromagnetic wave by the lens is greater than that of the electromagnetic wave propagating in other directions; The lens comprises a plurality of conductive tube layers arranged along the central longitudinal axis, each of the conductive tube layers comprises a plurality of short conductive tubes separated from each other by light dielectric materials, and light dielectric materials are arranged between adjacent conductive tube layers; The minimum distance between adjacent short conductive tubes in the same conductive tube layer is defined as H1, and the distance between adjacent conductive tube layers is defined as H2; Among them, H2 is greater than H1.

2. The high-gain dual-polarized dielectric metastructure antenna according to claim 1, characterized in that: The lens is in the shape of a cylinder.

3. The high-gain dual-polarized dielectric metastructure antenna according to claim 2, characterized in that: The lens has at least one end extending along the central longitudinal axis and provided with a protrusion, wherein: The protrusion is arranged in a hemispherical shape; Alternatively, the protrusion is arranged in a truncated cone shape, and the end surface area of ​​the protrusion close to the lens side is larger than the end surface area away from the lens side.

4. The high-gain dual-polarized dielectric metastructure antenna according to claim 1, characterized in that: The lens is in the shape of a rod having a triangular or polygonal cross section.

5. The high-gain dual-polarized dielectric metastructure antenna according to claim 4, characterized in that: The lens has at least one end extending along the central longitudinal axis direction with a protrusion, the protrusion is arranged in a prism shape, and the end surface area of ​​the protrusion close to the lens side is larger than the end surface area away from the lens side.

6. The high-gain dual-polarized dielectric metastructure antenna according to claim 1, characterized in that: The short conductive tubes in the conductive tube layer form a polygonal or sunflower-shaped lattice.

7. The high-gain dual-polarized dielectric metastructure antenna according to claim 1, characterized in that: The conductive tube layer includes a first conductive tube layer and a second conductive tube layer, wherein the second conductive tube layer is arranged at an end of the first conductive tube layer away from the metal reflective plate and / or at an end close to the metal reflective plate; When the second conductive tubes are arranged in layers at one end of the first conductive tube layers away from the metal reflective plate, the lens is driven to match the free space; When the second conductive tubes are arranged in layers at one end of the first conductive tube layer close to the metal reflective plate, the lens is driven to match the dual-polarization radiation element.

8. The high-gain dual-polarized dielectric metastructure antenna according to claim 7, characterized in that: The number of the short conductive tubes included in the second conductive tube layer is less than the number of the short conductive tubes included in the first conductive tube layer.

9. The high-gain dual-polarized dielectric metastructure antenna according to claim 1, characterized in that: The shape of the metal reflective plate is circular or polygonal.

10. The high-gain dual-polarized dielectric metastructure antenna according to claim 1, characterized in that: It also includes a conductive side plate, which is arranged on the outer edge of the metal reflective plate.

11. The high-gain dual-polarized dielectric metastructure antenna according to claim 1, characterized in that: It also includes an antenna cover, in which the metal reflector, the dual-polarization radiation element and the lens are all accommodated.

12. A dual-polarization MIMO antenna, characterized in that: The invention comprises a high-gain dual-polarized dielectric metastructure antenna and a radome as claimed in any one of claims 1 to 10, wherein: At least two of the dual-polarization radiating elements are placed side by side on the metal reflector, a lens is placed on the side of each dual-polarization radiating element away from the metal reflector, and the metal reflector, the dual-polarization radiating element and the lens are all accommodated in the antenna cover.

13. A dual-polarization multi-frequency antenna, characterized in that: The high-gain dual-polarized dielectric metastructure antenna according to any one of claims 1 to 11, wherein: At least two dual-polarization radiating elements are placed side by side on the metal reflector, a lens is placed on a side of each dual-polarization radiating element away from the metal reflector, and at least two dual-polarization radiating elements operate in different frequency bands.

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