WO2013016924A1 - Resonant cavity and filter having the resonant cavity - Google Patents

Abstract

A resonant cavity and a filter having the resonant cavity, comprising a cavity (1) and a harmonic oscillator disposed in the cavity. The harmonic oscillator comprises at least one rectangular cuboid metamaterial (2, 3, 4). Each piece of metamaterial comprises at least one material lamella. Each material lamella comprises a substrate and a man-made microstructure adhering to the substrate. Each piece of metamaterial is stacked along the height direction of the metamaterial, and the height directions of any two adjacent pieces of metamaterial are perpendicular to each other. By changing the positions of the adjacent materials in the resonant cavity, the resonant frequency of the resonant cavity can be decreased, and the performance of the resonant cavity can be improved, thereby facilitating miniaturization of the resonant cavity.

Description

 Resonant cavity and filter having the same

 The present application claims priority to Chinese Patent Application No. 20111021642, filed on Jan. 29, 2011, which is incorporated herein by reference. Technical field

 The present invention relates to the field of wireless communications, and more particularly to a resonant cavity and a filter having the same. Background technique

 The resonant cavity is a resonant component that operates at a microwave frequency and includes an arbitrary shape of a cavity surrounded by a conductive wall (or a magnetically conductive wall) and capable of forming an electromagnetically oscillating dielectric region therein, which has a storage electromagnetic energy and a certain selection The characteristics of the frequency signal. In the S parameter characterizing its performance, S11 is the input reflection parameter, that is, the input return loss, and the smaller the value, the better; S21 is the forward transmission parameter, that is, the gain, and the closer the value is to OdB, the better. The resonant frequency of the microwave cavity depends on the volume of the cavity. Generally, the larger the cavity volume is, the lower the resonance frequency is. The cavity volume is reduced. The higher the resonance frequency is, so how to achieve the case without increasing the cavity size. Reducing the resonant frequency of the resonant cavity is of great significance for the miniaturization of the resonant cavity. Summary of the invention

 The technical problem to be solved by the present invention is to provide a resonant cavity which can reduce the resonant frequency without increasing the size of the cavity and which has better performance.

 The present invention provides a resonant cavity including a cavity and a resonator disposed within the cavity. The resonator includes at least one cuboid metamaterial, each of the metamaterials including at least one sheet of material, each sheet of material comprising a substrate and an artificial microstructure attached to the substrate, the blocks of metamaterials The layers are sequentially stacked in the height direction of the metamaterial, and the length directions of the adjacent two metamaterials are perpendicular to each other.

 Wherein, each of the block metamaterials is sequentially stacked in a vertical direction.

 Wherein, a cavity is disposed in the cavity, and the resonator is fixed on the support, and the support is made of a microwave wave transmitting material.

Wherein, the support is made of foam. Wherein, the support is a cylindrical structure. The liquid substrate material is filled and cured, and the two are fused together to form a whole.

 Wherein, adjacent substrates are fused together by mechanical or by filling a liquid substrate material between two adjacent substrates to form a whole.

 Wherein, the artificial microstructure comprises four branches, and any of the branches overlaps the other three branches respectively by rotating 90 degrees, 180 degrees and 270 degrees clockwise with a point as a center of rotation.

 Wherein one end of any one of the branches of the artificial microstructure is an intersection of the four branches, and the other end is a free end connected with a line segment.

 Wherein the free end of any of the branches of the artificial microstructure is connected to the midpoint of the line segment. Wherein the branch road comprises at least one bent portion.

 Wherein, the bent portion of the artificial microstructure is a right angle, a rounded corner or a sharp corner.

 Wherein each of the branches includes a T-shape and at least one line segment that intersects the T-shaped intermediate connection line and is divided by the T-shaped intermediate connection line.

 Wherein, the substrate is a ceramic material.

Wherein, the substrate is made of polytetrafluoroethylene, ferroelectric material, ferrite material, ferromagnetic material, SiO ₂ or FR-4.

 Wherein, the artificial microstructure is made of metal wire.

 Wherein, the artificial microstructure is made of copper wire.

 Wherein, the artificial microstructure is made of silver wire.

 Wherein, the metal wire used in the artificial microstructure has a cross section of a cylindrical shape or a flat shape.

 Accordingly, embodiments of the present invention also provide a filter including at least one of the above-described resonant cavities.

The technical solution of the present invention has the following beneficial effects: According to the technical solution of the present invention, by changing the position of the adjacent metamaterials in the resonant cavity, the resonant frequency of the resonant cavity can be lowered to improve the performance of the resonant cavity, which is beneficial to achieve resonance. The miniaturization of the cavity. BRIEF DESCRIPTION OF THE DRAWINGS The drawings, which are required to be used in the description of the drawings or in the description of the prior art, are described in detail in the drawings. The drawings in the drawings are only some embodiments of the present invention, and those skilled in the art can obtain other drawings according to the drawings without any inventive labor.

 1 is a schematic structural view of a resonant cavity in the first embodiment;

 2 is a schematic view showing the arrangement of artificial microstructures on a material layer in the metamaterial 2 of FIG. 1; FIG. 3 is a plan view of three metamaterials in FIG.

 Figure 4 is a characteristic diagram of the S11 parameter of the resonant cavity of Figure 1;

 Figure 5 is a characteristic diagram of the S21 parameter of the resonant cavity of Figure 1;

 6 is a schematic structural view of three metamaterials in the resonant cavity of FIG. 1 when the horizontal direction is not rotated; FIG. 7 is a characteristic curve of the S11 parameter of the resonant cavity of FIG.

 Figure 8 is a characteristic diagram of the S21 parameter of the resonant cavity of Figure 6;

 9 is a schematic structural view of a resonant cavity in the second embodiment;

 Figures 10 through 17 are schematic views of possible structures of an artificial microstructure. Specific embodiment

 The invention relates to a resonant cavity for a filter, the filter comprising at least one of the resonant cavities. As shown in FIG. 1, the resonant cavity comprises a cavity 1, three cuboidal metamaterials 2, 3 and 4 disposed in the cavity 1, the metamaterial 2 comprises 8 material sheets, and the metamaterial 3 comprises 2 The material layer, the metamaterial 4 comprises two material sheets, each material layer comprises a substrate and an artificial microstructure attached to the substrate, the substrate is made of a ceramic material, and the thickness of the ceramic material is 1 mm, of course, the polymer can also be selected. Made of materials, PTFE, ferroelectric materials, ferrite materials, ferromagnetic materials, SiO 2 or FR-4. The artificial microstructure is a structure having a certain geometric shape composed of a wire, wherein the wire is made of copper wire, and the cross section of the selected copper wire is rectangular, and the cross-sectional dimension is 0.1 mm X 0.018 mm, wherein the line width of the copper wire is 0.1 mm, the thickness of the copper wire is 0.018 mm. Of course, the metal wire may also use other metal wires such as a silver wire. The cross section of the metal wire may also be cylindrical, flat or other shapes, and the size may be other sizes. In the present embodiment, the structure of the artificial microstructure is two I-shapes orthogonal to each other, and the intersection point is located at the midpoint of the two I-shapes.

The cavity 1 shown in Fig. 1 is a cube of 30 mm X 30 mm X 30 mm, the size of the metamaterial 2 is 12 mm X 18 mm X 8.144 mm, and the size of the metamaterial 3 is 12 mm χ 18 mm χ 2.036 mm, The size of the metamaterial 4 is 12 mm X 18 mm X 2.036 mm. The metamaterials 2, 3, and 4 are sequentially stacked in the height direction of the metamaterial, and the length directions of the adjacent two metamaterials are perpendicular to each other. Real In the embodiment, the adjacent metamaterials are vertically stacked 90 degrees and then vertically stacked together, and the adjacent material sheets and the different metamaterials are mechanically connected or filled between adjacent substrates, for example, a substance that can connect the two. a liquid substrate material which, after curing, bonds adjacent two substrates to form a plurality of material sheets and different metamaterials as a whole; as shown in FIG. 2, each substrate is virtually divided into 24 units. Each unit is 3 mm x 3 mm, and each person has a micro-structure attached to it; the top view of the three meta-materials in Figure 1 is shown in Figure 3, and the adjacent meta-materials are rotated 90 degrees in the horizontal direction, artificial micro The structure includes four T-shaped branches with co-intersection points. Each branch is rotated clockwise by 90 degrees, 180 degrees and 270 degrees with the intersection point as the center of rotation, and then coincides with the other three branches.

 Through experimental test, it can be seen that when the metamaterial is not placed in the cavity 1, the resonant frequency of the corresponding cavity is 10.63 GHz; when the metamaterial shown in Fig. 1 is placed in the cavity 1, the resonant frequency of the cavity is 2.94 GHz. As shown in FIG. 4 and FIG. 5, the parameter S11 corresponding to the cavity at the resonance point is -38.079 dB, and S21 is -0.5929 dB. As shown in FIG. 6, when the three metamaterials 2, 3, and 4 in the cavity 1 are not rotated in the horizontal direction, the resonant frequency of the corresponding cavity is 3.029 GHz, as shown in FIG. 7 and FIG. 8, at the resonance point. The parameter S11 corresponding to the cavity is -17.986 dB, and S21 is -1.05 dB. S11 is the input reflection parameter, that is, the input return loss, the smaller the value, the better; S21 is the forward transmission parameter, and the closer the value is to the OdB, the better. It can be seen from the experimental results that by changing the relative placement position of adjacent metamaterials in the cavity, the resonance frequency of the cavity can be lowered to improve the performance of the cavity, which is advantageous for miniaturization of the cavity.

 Embodiment 2

 The present embodiment is different from the first embodiment in that, as shown in FIG. 9, a cavity 5 is disposed in the cavity 1 under the metamaterial 2 for supporting three metamaterials located thereon, and the support 5 is foamed. The cylindrical structure can be made, and the support 5 can also be other structures. As long as the super material 2 can be supported, the support can also be made of other microwave-transparent materials, and the microwave-transparent material refers to the wavelength of l~ A material having a transmittance of 1000 mm and an electromagnetic wave having a frequency in the range of 0.3 to 300 GHz of more than 70% may be an inorganic material, a polymer material, an inorganic/polymer composite material, or a diamond material.

The embodiments of the present invention have been described above with reference to the drawings, but the present invention is not limited to the specific embodiments described above, and the specific embodiments described above are merely illustrative and not restrictive, and those skilled in the art In the light of the present invention, many modifications may be made without departing from the scope of the invention and the scope of the claims. For example, the shape of the artificial microstructure may also be as shown in Figs. 10 and 11, the artificial micro The structure includes four branches of the co-intersection point, each branch including a T-shape and at least one line segment intersecting the T-shaped intermediate connection line and being bisected by the T-shaped intermediate connection line, the line segment The lengths can be the same or different. The artificial microstructure can also be shown in Figures 12 to 17, each of the artificial microstructures comprising four branches of a common intersection, each of which is rotated clockwise by 90 degrees, 180 degrees and 270 degrees with the intersection as the center of rotation. Respectively coincide with the other three branches, each branch includes at least one bent portion, each bent portion may be a right angle, a rounded corner or a sharp corner, and one end of each branch is the intersection of four branches, and the other One end is a free end, and the free end can be suspended or connected to a midpoint of the line segment. The four branches of the artificial microstructure may also not co-intersection, and respectively rotate 90 degrees, 180 degrees, and 270 degrees clockwise with respect to a point in the space to coincide with the other three branches. For the sake of sizing, the structures in Figs. 10 to 17 are all drawn with thin lines, and in fact, the above structures all have a certain width. These are all within the protection of the present invention.

 The embodiments of the present invention have been described above with reference to the drawings, but the present invention is not limited to the specific embodiments described above, and the specific embodiments described above are merely illustrative and not restrictive, and those skilled in the art In the light of the present invention, many forms may be made without departing from the spirit and scope of the invention as claimed.

Claims

Rights request A resonant cavity comprising a cavity and a resonator disposed within the cavity, wherein the resonator includes at least one cuboid metamaterial, each of the metamaterials comprising at least one layer of material, Each of the material sheets includes a substrate and an artificial microstructure attached to the substrate, the blocks of the metamaterial being sequentially stacked in a height direction of the metamaterial, and the length directions of the adjacent two metamaterials are perpendicular to each other.  2. The resonant cavity according to claim 1, wherein each of the block metamaterials is sequentially stacked in a vertical direction.  3. The resonant cavity according to claim 1 or 2, wherein a cavity is provided in the cavity, and the resonator is fixed on the support, and the support is made of a microwave wave permeable material.  4. The resonant cavity of claim 3, wherein the support is made of foam. 5. The resonant cavity of claim 3, wherein the mount is a cylindrical structure. 6. A resonant cavity according to claim 1 or 2, wherein adjacent layers of material are fused together to form a unitary body.  The resonant cavity according to claim 1 or 2, wherein the adjacent substrates are fused by mechanical or by filling a liquid substrate material between two adjacent substrates and then solidifying Together form a whole.  The resonant cavity according to claim 1 or 2, wherein the artificial microstructure comprises four branches, and any one of the branches is rotated clockwise by 90 degrees, 180 degrees, and sequentially with a point as a center of rotation. After 270 degrees, it coincides with the other three branches.  9. The resonant cavity according to claim 8, wherein one end of any one of the branches of the artificial microstructure is an intersection of the four branches, and the other end is a free end connected with a line segment.  10. A resonant cavity according to claim 9 wherein the free end of any of said branches of said artificial microstructure is connected to the midpoint of said line segment.  11. A resonant cavity according to claim 9 or 10, wherein the branch comprises at least one bend.  The resonant cavity according to claim 11, wherein the bent portion of the artificial microstructure is a right angle, a rounded corner or a pointed corner. 13. The resonant cavity of claim 8 wherein each of said branches comprises a T-shape and The T-shaped intermediate connecting lines intersect and are at least one line segment bisected by the meandering intermediate connecting line.  The resonant cavity according to claim 1 or 2, wherein the substrate is a ceramic material. The resonant cavity according to claim 1 or 2, wherein the substrate is made of polytetrafluoroethylene, ferroelectric material, ferrite material, ferromagnetic material, SiO ₂ or FR-4.  16. The resonant cavity according to claim 1 or 2, wherein the artificial microstructure is made of a metal wire.  17. The resonant cavity of claim 16, wherein the artificial microstructure is made of copper wire.  18. The resonant cavity of claim 16, wherein the artificial microstructure is made of silver wire.  19. The resonant cavity according to claim 16, wherein the metal wire used in the artificial microstructure has a cylindrical or flat cross section.  A filter comprising at least one resonant cavity according to any of claims 1-19.