CN104538721A - Metamaterial harmonic oscillator based on metal-structure LC resonator and application thereof - Google Patents

Abstract

The invention discloses a metamaterial harmonic oscillator based on a metal-structure LC resonator and application of the metamaterial harmonic oscillator. The metamaterial harmonic oscillator is a conductive metal body provided with a notch. An inductor part L of the metamaterial harmonic oscillator is made of conductive metal material, a capacitor part C of the metamaterial harmonic oscillator is composed of the notch, and the two end faces of an inductor L serve as electrodes of the capacitor part C. The shape of the notch is random. The number of metamaterial harmonic oscillators, applied to microwave devices, based on the metal-structure LC resonator is at least one. By introduction of the metamaterial harmonic oscillator, miniaturization and integration of various microwave devices such as a filter, a coupler and a multiplexer are achieved, and meanwhile the transmission efficiency of the microwave devices is improved.

Description

A metamaterial resonator based on metal structure LC resonator and its application

technical field

The invention belongs to the field of materials, and relates to a metamaterial resonator based on a metal structure LC resonator and an application thereof.

Background technique

The miniaturization and integration of microwave devices is the goal that the electronic information industry is constantly pursuing. Many microwave devices, such as filters, couplers, and multiplexers, have functions such as selective transmission of electromagnetic signals and suppression of out-of-band signals. One of the core components used in these microwave devices is the resonator. Most of the resonators in use today are made of rectangular or other shaped metal cavities and large cylindrical dielectrics, which generally occupy a large volume, especially at low frequencies. In order to achieve good frequency selection characteristics and suppress the passage of clutter signals, it is generally necessary to combine several such resonators. Therefore, various microwave devices composed of several such resonators must occupy a larger volume, which brings great problems to the miniaturization and integration of microwave devices.

In the past ten years, the emergence of metamaterials has shown infinite beauty in the miniaturization and integration of various microwave devices. Metamaterials are formed by periodic arrangement of artificial electromagnetic resonant unit structures. The response of each resonant unit to the external electromagnetic field can be expressed as electrical resonance, magnetic resonance or electromagnetic resonance, which are used to achieve macroscopic equivalent negative permittivity and negative permeability. The periodic arrangement of harmonic oscillators with negative permittivity and negative magnetic permeability can realize the left-handed transmission characteristics of electromagnetic waves, thereby realizing many strange functions that materials in nature cannot have. Since metamaterials use larger resonant units (compared to atomic molecules) to replace atoms or molecules in crystals, the operating frequency is reduced from x-ray-ultraviolet-infrared frequency bands to light waves-microwave frequency bands.

However, most of the current research on metamaterials focuses on the macroscopic effect of a large number of artificial electromagnetic harmonic oscillators periodically arranged, and there is very little research and application on several or even one such metamaterial harmonic oscillator.

Contents of the invention

The object of the present invention is to provide a metamaterial resonator based on a metal structure LC resonator and its application.

The metamaterial resonator provided by the present invention is a body of conductive metal material; the body has a gap.

The conductive metal material can specifically be copper.

The inductance L part of the metamaterial resonator is composed of the conductive metal material, the capacitance C part is composed of the gap, and the two end surfaces of the inductance L part serve as electrodes of the capacitance C part.

The shape of the notch is arbitrary.

The response of the structure composed of the inductance L part and the capacitance C part to electromagnetic waves is equivalent to LC resonance.

In addition, the microwave device containing the metamaterial resonator provided by the present invention and the application of the metamaterial resonator in manufacturing microwave devices also belong to the protection scope of the present invention. Wherein, the number of the metamaterial harmonic oscillator is at least one, specifically two. Specifically, the microwave device may be a filter, a coupler or a multiplexer.

The working state of the metal structure resonator has three states: electric resonance, magnetic resonance and electromagnetic resonance, and different resonance states correspond to different resonance frequencies. In a specific implementation process, any resonance state of the metamaterial harmonic oscillator can be selected. The electromagnetic resonance (LC resonance) of the metal structure resonator corresponds to the lowest resonance frequency, which is generally selected as the coupled resonance state of the metamaterial resonator.

For the metamaterial electromagnetic resonators provided by the present invention, they themselves are good electromagnetic resonators. Moreover, compared with harmonic oscillators composed of traditional materials and traditional methods, these artificially designed metamaterial harmonic oscillators have the characteristics of high quality factor and sub-wavelength resonance, and they can confine the incident electromagnetic wave to a very small range for a long time. Therefore, it can bring breakthrough progress in the miniaturization, integration and transmission efficiency of various microwave devices.

For a single metamaterial resonator, when the frequency of the external electromagnetic wave is equal to the resonant frequency of the resonator, the energy of the electromagnetic wave is mainly concentrated in the metamaterial resonator and cannot continue to propagate forward, thus forming a " notch point". The subsequent electromagnetic energy is almost all reflected back and cannot be transmitted. However, if there are several metamaterial resonators in this propagation direction, the situation is quite different. For example, when two metamaterial harmonic oscillators are placed in the direction of wave propagation in sequence, the two harmonic oscillators will be divided into three situations: over-coupling, critical coupling and under-coupling according to the distance between them. In the case of critical coupling, electromagnetic waves can be fully coupled to the exit end, and the transmission efficiency is also very high, which can be regarded as total transmission without loss. In the case of under-coupling, there is still a high transmission efficiency at the resonant frequency, but compared with the critical coupling, the transmission efficiency drops a lot. In the case of over-coupling, two resonant frequency points respectively lower and higher than the original resonant frequency can be generated. The coupling between the multiple metamaterial harmonic oscillators of the present invention can adopt any situation.

Compared with the prior art, the present invention has the following beneficial effects:

The invention solves the problems of large size and low integration when the resonators manufactured by traditional materials and methods are used in various microwave devices, and adopts the metal structure LC resonator to realize the metamaterial resonator. These metamaterial harmonic oscillators have the characteristics of high quality factor and sub-wavelength resonance. They can confine the incident electromagnetic wave to a very small range and periodically oscillate efficiently for a long time. Therefore, they are widely used in the miniaturization, integration and It has huge advantages in transmission efficiency and other issues.

Description of drawings

FIG. 1 is a schematic diagram of a microwave coupler formed based on the critical electromagnetic resonance coupling between two metamaterial resonators of a metallic structure LC resonator.

FIG. 2 is a diagram of the simulation results of the microwave coupler in Embodiment 1.

Figure 3 is a schematic diagram of a dual-frequency point microwave band-stop filter formed based on the electromagnetic resonance coupling between two metamaterial resonators of a metal structure LC resonator

FIG. 4 is a diagram of the simulation results of the dual-frequency point microwave band rejection filter in Embodiment 2.

Detailed ways

The present invention will be further described below in conjunction with specific examples, but the present invention is not limited to the following examples. The methods are conventional methods unless otherwise specified. The raw materials can be obtained from open commercial channels unless otherwise specified.

Example 1

FIG. 1 is a schematic diagram of a microwave coupler formed based on the critical electromagnetic resonance coupling between two metamaterial resonators of a metallic structure LC resonator. The metamaterial resonator based on the metal structure LC resonator shown in the figure is a metal copper split resonator ring structure printed by printed circuit board technology. The metamaterial resonator is composed of a copper body, and the copper body has a gap. The shape of the metamaterial resonator is a copper ring with a gap. The side length of the copper ring is 4mm, the width is 0.5mm, and the gap is 0.3mm. The gap part is equivalent to the capacitance C, and the other metal parts are equivalent to the inductance L, thus forming a standard LC resonator. The thickness of the metal plate in Figure 1 is 1mm, and there is a circular hole with a radius of 2.5mm in its center, so that electromagnetic waves can be coupled to the other side of the metal plate. If only the round hole participates in the coupling, it can couple to the opposite electromagnetic wave very weakly. However, if a metamaterial resonator based on a split metal ring structure is placed on both sides of the circular hole in the metal plate, the coupling strength at this time is shown in Figure 2. In the range of 9.5-10GHz, almost all electromagnetic waves can Coupled to the opposite side of the round hole. In addition, compared with the working wavelength of the implemented coupler, the size of the metamaterial resonator used here is much smaller than its working wavelength, that is, it meets the requirements of the sub-wavelength scale, so the metamaterial based on the metal ring structure is successfully realized A miniaturized microwave coupler formed by coupling between resonators.

Example 2

FIG. 3 is a schematic diagram of a dual-frequency point microwave band-stop filter formed based on electromagnetic resonance coupling between two metamaterial resonators of a metal structure LC resonator. The metamaterial resonator shown in the figure is a metal copper split resonator ring structure printed by printed circuit board technology. The metamaterial resonator is composed of a copper body, and the copper body has a gap. The shape of the metamaterial resonator is a copper ring with a gap. The side length of the copper ring is 5mm, the width is 0.75mm, and the gap is 1mm. The gap part is equivalent to the capacitance C, and the other metal parts are equivalent to the inductance L, thus forming a standard LC resonator. When the distance between the two resonators is 2 mm, the transmission coefficient of the formed dual-frequency point band-stop filter is shown in Figure 4. In the figure, there are two obvious notch points at 6.1GHz and 7.1GHz, thus realizing a high-performance band-stop filter. In addition, compared with the operating wavelength of the realized filter, the size of the metamaterial harmonic oscillator used here is much smaller than its operating wavelength, that is, it meets the requirements of the sub-wavelength scale, so the metamaterial based on the metal ring structure is successfully realized. A miniaturized microwave band-stop filter formed by coupling between harmonic oscillators.

Claims (7)

1. A metamaterial harmonic oscillator, which is a conductive metal material body; The body has a notch. 2. The metamaterial resonator according to claim 1, wherein the conductive metal material is copper. 3. The metamaterial resonator according to claim 1 or 2, characterized in that: in the metamaterial resonator, the inductance L part is made of the conductive metal material, the capacitance C part is made of the gap, and the The two end surfaces of the part L of the inductance are used as the electrodes of the part C of the capacitor. 4. A microwave device containing the metamaterial resonator according to any one of claims 1-3. 5. The microwave device according to claim 4, characterized in that: in the microwave device, the number of metamaterial harmonic oscillators is at least one; The microwave device is a filter, a coupler or a multiplexer. 6. The application of the metamaterial resonator according to any one of claims 1-3 in the manufacture of microwave devices. 7. The application according to claim 6, characterized in that: in the microwave device, the number of metamaterial harmonic oscillators is at least one; The microwave device is a filter, a coupler or a multiplexer.