WO2013037172A1

WO2013037172A1 - Resonant cavity and filter having same

Info

Publication number: WO2013037172A1
Application number: PCT/CN2011/083866
Authority: WO
Inventors: 刘若鹏; 栾琳; 刘京京; 钟果; 任春阳; 徐国伟
Original assignee: 深圳光启高等理工研究院; 深圳光启创新技术有限公司
Priority date: 2011-09-16
Filing date: 2011-12-13
Publication date: 2013-03-21
Also published as: CN103000979A; CN103000979B

Abstract

Provided is a resonant cavity, including a cavity body, at least two metamaterial plates located inside the cavity body, each metamaterial plate including at least one metamaterial sheet, the cavity body being further installed thereon with an adjustment device for adjusting the relative position between the at least two metamaterial plates. The present invention realizes the purpose of frequency reduction by way of placing a metamaterial plate in a resonant cavity and using the high refractive index property of metamaterial, and further realizes trimming of the resonant frequency under the condition of reduced frequency by providing an adjustment device for the metamaterial plate to make the relative position between each metamaterial plate adjustable, which can meet more accurate filtering demands. In addition, also provided is a filter having said resonant cavity.

Description

Resonant cavity and filter having the same

The present application claims priority to Chinese Patent Application Serial No. 2011-102 752, the entire disclosure of which is hereby incorporated 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

In microwave devices, cavity filters are a very important device. The cavity filter is composed of several microwave resonators, each cavity having an arbitrary shape of a cavity surrounded by a conductive wall (or a magnetic conductive wall). Usually, a resonant cavity has a fixed resonant frequency, and generally the smaller the resonant cavity volume, the higher the resonant frequency. Therefore, some resonant cavities with low resonant frequencies are relatively bulky.

In order to adjust the cavity of a known frequency point, a tuning screw is usually placed at the top of the cavity to adjust the frequency of the cavity by adjusting its depth into the cavity. However, this type of adjustment is usually accompanied by an increase in loss. And for the cavity that is inserted into the medium, the use of screw adjustment does not achieve a practical and effective frequency reduction effect. Summary of the invention

The technical problem to be solved by the present invention is to provide a metamaterial resonant cavity capable of down-converting and fine-tuning down-regulation for the defects of the above-described down-conversion method of the prior art.

The present invention provides a resonant cavity including a cavity, at least two metamaterial sheets located in the cavity, each of the metamaterial sheets including at least one metamaterial sheet, and the cavity is further mounted to adjust the at least A device for adjusting the relative position between two metamaterial plates.

Wherein, the adjusting device is a device for adjusting the spacing between two adjacent metamaterial plates and/or a device for adjusting the relative angle between the two.

Wherein the adjusting device includes a first link hinged to one of the metamaterial plates by a hinge shaft, a second link hinged to the other end of the first link, and a pivot, the first The connecting rod is provided with a sliding slot extending along the axial direction of the first connecting rod, and the pivoting shaft is connected perpendicularly to the bottom surface of the cavity The bottom surface of the cavity is slidably connected to the sliding slot.

Wherein the first link is parallel to the bottom surface of the cavity, and the second link vertically passes through the sidewall of the cavity.

Wherein, the second connecting rod is provided with two limiting flanges, wherein one limiting flange is located inside the side wall of the cavity, and the other is located outside the side wall of the cavity, and between the two The distance is greater than the sidewall thickness.

Wherein, the end of the second connecting rod passing through the side wall of the cavity to expose the cavity is provided with an operating handle. Wherein, each of the metamaterial boards is connected with the adjusting device, and the second connecting rods of each adjusting device are arranged in parallel with each other.

Wherein, the adjusting device is a rack and pinion mechanism.

Wherein, the gear of the rack and pinion mechanism is provided with an operation knob exposed outside the cavity. Wherein, the metamaterial sheet layer comprises a non-metal substrate and an artificial microstructure made of a conductive material attached to the substrate.

Wherein, the artificial microstructure is formed by two "work" shapes orthogonal to each other.

Wherein, the artificial microstructure is spirally wound by a wire from the inside to the outside.

Wherein, the artificial microstructure is composed of a plurality of circular split rings nested with each other.

Wherein, the artificial microstructure comprises four identical branches, and any of the branches rotates 90 degrees around a center of rotation and then coincides with the adjacent branches.

Wherein the artificial microstructure is made of metal.

Wherein the artificial microstructure is made of silver or copper.

Wherein, the artificial microstructure is composed of a non-metal conductive material.

Wherein the artificial microstructure is made of ITO.

Wherein the substrate is selected from the group consisting of FR-4, polytetrafluoroethylene, epoxy resin, ceramic, ferroelectric material, ferrite material, ferromagnetic material and SiO2.

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

The implementation of the resonant cavity of the present invention has the following beneficial effects: The present invention achieves the purpose of frequency reduction by placing a metamaterial plate in the cavity and utilizing the high refractive index characteristics of the metamaterial; further, by adjusting the super material plate The device makes the relative position between the super-material plates adjustable, thereby realizing fine-tuning of the resonant frequency under the condition of frequency reduction, which can meet more precise filtering requirements. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in the claims Other drawings may also be obtained from these drawings without the inventive labor.

1 is a schematic structural view of a resonant cavity of a preferred embodiment of the present invention;

Figure 2 is a plan view of the resonant cavity of the present invention;

Figure 3 is a schematic structural view of a super-material sheet;

Figures 4 through 11 are several possible shapes of an artificial microstructure. Specific embodiment

The invention relates to a resonant cavity, as shown in Fig. 1 and Fig. 2, comprising a cavity 2, a plurality of metamaterial plates 4 and an adjusting device. Wherein, the cavity 2 has an approximately square inner space, and a cavity cover 1 may be disposed above to close the space. An input end 3 and an output end may also be disposed on both side walls of the resonant cavity.

An innovation of the present invention is that a plurality of metamaterial sheets 4 and adjustment means connected to each of the metamaterial sheets 4 are disposed inside the cavity 2 for adjusting the relative positions between the adjacent two metamaterial sheets 4, Thereby changing the resonant frequency of the resonant cavity.

Metamaterial, also known as artificial electromagnetic material, is a material that has a special response to electromagnetic waves. It is formed by a dielectric substrate and artificial microstructures periodically arranged on the surface of the dielectric substrate. The artificial microstructure is usually metal. Made of a conductive material. By designing the geometry, size and arrangement of the artificial microstructure, it is possible that the metamaterial as a whole exhibits special, even natural, properties that are difficult to achieve, such as higher dielectric constant, negative magnetic permeability, negative Characteristics such as refractive index. The metamaterial board of the present invention employs this technique, and utilizes the high dielectric constant characteristics of the metamaterial to achieve the effect of reducing the resonant cavity frequency.

Each of the metamaterial sheets 4 includes at least one metamaterial sheet 40, and each of the metamaterial sheets 40, as shown in FIG. 3, includes a substrate 41 and a plurality of artificial microstructures 42 attached to the substrate 41. The substrate 41 is usually made of a non-metal material such as FR-4, polytetrafluoroethylene, epoxy resin, ceramic, ferroelectric material, ferrite material, ferromagnetic material, SiO _{2 ,} and the like. The artificial microstructure 42 is a geometrical planar or three-dimensional structure composed of wires of a conductive material, and the conductive material here is usually a metal such as copper, silver, or the like, and may be other non-metallic conductive materials such as ITO, conductive plastic, and the like. Each metamaterial panel 4 includes a plurality of metamaterials In the case of the sheet layer 40, the surfaces of the respective super-material sheet layers 40 are joined together in a single piece by a mechanical joint, an adhesive or other means of linking.

The artificial microstructures 42 are generally arranged periodically on the surface of the substrate 41, for example, in a rectangular array, and each of the artificial microstructures 42 is the same; or the plurality of artificial microstructures 42 may have different shapes and sizes, for example, according to a certain The increasing or decreasing law gradually reduces its size or rotates its orientation. These features can be designed point-to-point according to different actual needs, such as the demand of refractive index distribution, the permeability distribution requirement, and the like. Preferably, each of the metamaterial sheets is the same in the present invention, and each of the metamaterial sheets 40 has a plurality of identical artificial microstructures 42 and is arranged in a rectangular array.

The shape of the artificial microstructure 42 is various. Except for the structure in which the two "work" shapes shown in FIG. 3 are orthogonal to each other, the artificial microstructure obtained by serpentine winding as shown in FIGS. 4 and 5 The effect of high refractive index can also be achieved; in addition, the artificial microstructure 42 shown in Fig. 6 is a structure in which a wire is spirally wound from the inside to the outside; Fig. 7 shows a plurality of circular openings nested inside each other. An artificial microstructure consisting of a ring; Figures 8 and 9 show two isotropic structures, each having four identical branches, each of which is rotated 90 degrees around a center of rotation and adjacent The branches are coincident; Fig. 10 is an artificial microstructure composed of two inner and outer nested open resonant rings; Fig. 11 is an artificial micro-structure composed of two open-ended open resonant rings and a "work"-shaped structure.

The metamaterial sheet 40 of the artificial microstructure 42 having the above shape can be placed in the cavity to achieve the effect of reducing the resonance frequency. In this embodiment, each of the metamaterial sheets 4 has only one super material sheet 40. Further, in order to achieve the fine adjustment of the resonance frequency based on this, the present invention also provides an adjustment device on the metamaterial board 4. The adjustment means can be used to adjust the spacing between adjacent two metamaterial sheets 4, and can also be used to adjust the relative angle between them.

In a preferred embodiment, as shown in Fig. 2, each of the metamaterial panels 4 is provided with an adjustment device including a first link 5, a second link 9, and a pivot 6. Preferably, all three are located on the bottom surface of the cavity of the resonator.

As shown, the first link 5 - end is hinged to the bottom of the metamaterial sheet 4 by a hinge so that the first link 5 is rotatable relative to the metamaterial sheet 4. The other end of the first link 5 is provided with a sliding groove 7 at a position close to the end, and the sliding groove 7 extends in the axial direction of the rod, and a through hole is provided in a direction perpendicular to the bottom surface of the cavity. The pivot shaft 6 is fixed on the bottom surface of the cavity corresponding to the sliding slot 7, and its central axis is perpendicular to the bottom surface of the cavity and passes through the sliding slot 7. Preferably, the diameter of the pivot 6 is comparable to the groove width of the chute 7. Pushing the other end of the first link 5, the first link 5 is rotated about the pivot 6 while the pivot 6 is moved relative to the chute 7, and the metamaterial board 4 is connected One end is far from where it was before.

One end of the second link 9 is hinged to the end of the first link 5 and passes through the side wall perpendicular to the side wall of the cavity, preferably a through hole formed in the side wall of the cavity for facilitating the passage of the second link 9 Its diameter is equivalent to the outer diameter of the second link 9, so that the second link 9 can freely move axially therein without swaying radially. The first and second links are both placed parallel to the bottom surface of the cavity.

With such an adjusting device, the second link 9 is pushed inwardly on the outer side of the cavity, and the first link 5 is moved forward while rotating about the pivot 6, so that the metamaterial plate at the other end of the first link 5 4 away from the adjacent metamaterial board 4. The three metamaterial sheets 4 illustrated in Fig. 2 each have one such adjustment means, and it is apparent that three mutually parallel second links 9 can be integrally fixedly connected to each other to operate the three metamaterial sheets 4 at the same time. An operating handle may be provided at the end of the second link 9, that is, the portion exposed to the outside of the cavity, to facilitate the simultaneous pushing of the three second links.

In addition, as shown in FIG. 2, in order to define the moving distance and the moving range between the adjacent metamaterial plates 4, two limiting flanges 8 are disposed on each of the second connecting rods 9, one of which is a limiting flange. 8 is located inside the side wall of the cavity, and the other is located outside the side wall of the cavity, and the distance between the two is greater than the thickness of the side wall, thereby limiting the range of movement of the second link 9 between the two limiting flanges 8. .

With this adjustment means, the spacing between adjacent metamaterial sheets 4 can be adjusted. Obviously, in the existing mechanical design, there are more than four kinds of mechanisms for adjusting the distance between two adjacent metamaterial sheets 4, and as long as the volume, tooling, and effect are allowed, they can be applied to the present invention as an adjusting device, for example. A rack and pinion mechanism, a screw mechanism, or a mechanism for moving the cartridge along the chute. When the adjusting device is a rack and pinion mechanism, that is, a shaft-rotatable gear is mounted on the top wall of the cavity, an adapted rack is fixed on the top of the metamaterial board, and the rack is mounted on the side wall and can move axially. Then, the gear is rotated, and the gear drives the rack to move, thereby driving the super material plate to move, and the purpose of adjusting the distance between the super material plates and adjusting the resonance frequency can also be achieved. The gear is inside the cavity, and an operating knob can be mounted on the outside of the cavity to control the rotation of the gear.

Similarly, the adjustment means can be used to adjust the spacing between the metamaterial plates and to adjust the relative angle between them. Such a mechanism is also very much in the existing mechanical design. The mechanism of the single cylinder, such as directly installing a knob on each metamaterial board, rotating the knob to drive the rotation of the metamaterial board, a complicated mechanism such as a crank slider mechanism, etc. This article is no longer - repeat.

The present invention achieves the purpose of frequency reduction by placing a metamaterial plate in a cavity, and utilizing the high refractive index characteristic of the metamaterial; further, by providing an adjustment device for the metamaterial plate, the relative position between the metamaterial plates is made. Adjustable, and then achieve the fine-tuning of the resonant frequency under the condition of frequency reduction, which can meet more precise Filtering requirements.

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, at least two metamaterial plates located in the cavity, each metamaterial plate comprising at least one metamaterial sheet, and the cavity is further mounted with an adjustment An adjustment device for the relative position between the at least two metamaterial sheets.

2. A resonant cavity according to claim 1 wherein said adjusting means is means for adjusting the spacing between adjacent two metamaterial plates and/or means for adjusting the relative angle between the two.

3. The resonant cavity according to claim 2, wherein the adjusting device comprises a first link hinged to one of the metamaterial plates by a hinge shaft at one end, and hinged to the other end of the first link a second link and a pivot, the first link is provided with a sliding slot extending axially along the first link, the pivot is connected to the cavity perpendicular to a bottom surface of the cavity The bottom surface of the body is slidably coupled to the sliding groove.

4. The resonant cavity of claim 3, wherein the first link is parallel to the bottom surface of the cavity and the second link passes vertically through the sidewall of the cavity.

The resonant cavity according to claim 4, wherein the second connecting rod is provided with two limiting flanges, wherein one limiting flange is located inside the side wall of the cavity, and the other is located The outside of the sidewall of the cavity, and the distance between the two is greater than the thickness of the sidewall.

6. The resonant cavity of claim 4, wherein the second link passes through the sidewall of the cavity and the end of the exposed cavity is provided with an operating handle.

7. The resonant cavity according to claim 3, wherein each of the metamaterial plates is connected to the adjusting device, and the second links of each adjusting device are disposed in parallel with each other.

8. The resonant cavity of claim 1 wherein said adjustment means is a rack and pinion mechanism.

9. The resonant cavity according to claim 8, wherein the gear of the rack and pinion mechanism is provided with an operating knob that is exposed outside the cavity.

10. The resonant cavity of any of claims 1-9, wherein the metamaterial sheet comprises a non-metallic substrate and an artificial microstructure made of a conductive material attached to the substrate.

11. The resonant cavity of claim 10, wherein the artificial microstructure is formed orthogonally to each other by two "work" shapes.

12. The resonant cavity of claim 10, wherein the artificial microstructure consists of a wire The wire is spirally wound from the inside to the outside.

13. The resonant cavity of claim 10, wherein the artificial microstructure consists of a plurality of circular split rings that are nested together.

14. The resonant cavity of claim 10, wherein the artificial microstructure comprises four identical branches, each of which branches 90 degrees about a center of rotation and then coincides with an adjacent branch.

15. The resonant cavity of claim 10, wherein the artificial microstructure is made of metal.

16. The resonant cavity of claim 15 wherein the artificial microstructure is made of silver or copper.

17. The resonant cavity of claim 10, wherein the artificial microstructure is comprised of a non-metallic conductive material.

18. The resonant cavity of claim 17, wherein the artificial microstructure is made of ITO.

19. The resonant cavity according to claim 10, wherein the substrate is selected from the group consisting of FR-4, polytetrafluoroethylene, epoxy resin, ceramic, ferroelectric material, ferrite material, ferromagnetic material, and Si0 ₂ One of them.

A filter comprising at least one resonant cavity according to any of claims 1-19.