CN103746191A - Ultra-compact metamaterial wave-absorbing unit - Google Patents

Abstract

The invention discloses an ultra-compact metamaterial wave-absorbing unit, which comprises: a first metal thin film, a rectangular dielectric layer is arranged on the rectangular metal thin film, and a second metal thin film is arranged on the rectangular dielectric layer; The metal film is provided with a hollow, the hollow is composed of a first C-shaped hollow and a second C-shaped hollow, and the first C-shaped hollow and the second C-shaped hollow are arranged back to back, and the second metal film is formed by the first C-shaped metal foil and a second C-shaped metal foil, and the first C-shaped metal foil and the second C-shaped metal foil are arranged back to back, and the shape of the hollow is similar to the shape of the second metal film. The invention has the advantages of extremely thin thickness and wave-absorbing performance over -15dB.

Description

Ultra-compact metamaterial absorber

technical field

The invention relates to an ultra-compact metamaterial wave-absorbing unit.

Background technique

Traditional absorbing materials require a thicker size to obtain a better absorbing effect, but in the low frequency band, such as in the frequency range of 1-2GHz, the thickness of the absorbing material usually exceeds 10mm, which is practical in practical applications. It is severely restricted, especially in compact microwave circuits, and it is even more difficult to use. At the same time, the performance of traditional absorbing materials is only about -10dB, which is often difficult to meet the requirements in microwave circuits and antenna arrays.

For this reason, it is necessary to invent a material with an extremely thin thickness and a wave-absorbing performance exceeding -15dB, and the present invention can just meet such design requirements.

Contents of the invention

The invention provides an ultra-compact metamaterial wave-absorbing unit with extremely thin thickness and a wave-absorbing performance exceeding -15dB.

The present invention adopts following technical scheme:

An ultra-compact metamaterial wave-absorbing unit, comprising: a first metal film, a rectangular dielectric layer is provided on the rectangular metal film, a second metal film is provided on the rectangular dielectric layer, and a rectangular dielectric layer is provided on the first metal film. hollow, the hollow is composed of a first C-shaped hollow and a second C-shaped hollow, and the first C-shaped hollow and the second C-shaped hollow are set back to back, and the second metal film is composed of the first C-shaped metal foil and the second The C-shaped metal foil is composed of the first C-shaped metal foil and the second C-shaped metal foil arranged back to back, and the shape of the hollow is similar to the shape of the second metal film.

Compared with prior art, the present invention has following advantage:

The hollow and the second metal film are similar to each other, so that the first metal film and the second metal film are complementary to form a complementary metamaterial structure. This complementary metamaterial structure can first ensure that the input impedance of the entire absorbing unit is within a wide range. In the frequency band close to the wave impedance of air, it first overcomes the impedance matching problem of the metamaterial absorber in the traditional sense, which is the primary satisfying condition of the metamaterial absorber. Different from the double C-shaped external short microstrip line structure first proposed by Lindy in 2008, the structure located in the first metal film replaces the traditional long-sized short microstrip line structure, which can ensure that the entire structure has a large enough isotropic Effective inductance, while effectively reducing the size of the entire unit, this structure is also conducive to further reducing the thickness of the entire unit, and it is also based on the same hollow structure that brings a larger equivalent inductance. Therefore, the thickness of the present invention is less than 1/100 The working wavelength, the absorbing performance exceeds -15dB, while the thickness of conventional absorbing materials can only reach less than a few tenths of the working wavelength, and the absorbing performance is generally about -10dB.

Description of drawings

The above objects, other features and advantages of the present invention will be more apparent after reading the description in conjunction with the accompanying drawings, wherein:

Fig. 1 is a side view of the overall structure of the present invention.

Fig. 2 is a top view of the first metal thin film of the present invention.

Fig. 3 is an A-A sectional view of the first metal thin film of the present invention.

Fig. 4 is a top view of the rectangular dielectric layer of the present invention.

Fig. 5 is a top view of the second metal thin film of the present invention.

Fig. 6 is a curve of absorbing performance in an embodiment of the present invention.

Detailed ways

Example 1

An ultra-compact metamaterial wave-absorbing unit, comprising: a first metal film 1, a rectangular dielectric layer 3 is arranged on the rectangular metal film 1, a second metal film 4 is arranged on the rectangular dielectric layer 3, and the first A metal film 1 is provided with a hollow 2, the hollow 2 is composed of a first C-shaped hollow 21 and a second C-shaped hollow 22, and the first C-shaped hollow 21 and the second C-shaped hollow 22 are arranged back to back, and the second The metal film 4 is made of a first C-shaped metal foil 41 and a second C-shaped metal foil 42, and the first C-shaped metal foil 41 and the second C-shaped metal foil 42 are arranged back to back, and the shape of the hollow 2 is consistent with that of the second metal foil. The shapes of the films 4 are similar to each other. The projection of the second metal film 4 on the first metal film 1 falls inside the hollow 2 of the first metal film 1 .

The following is the detailed content of a preferred embodiment of the present invention, and the embodiment will be described with reference to the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings and descriptions to refer to the same or like parts. This embodiment is used for electromagnetic isolation of radio frequency circuits and isolation of microstrip antenna array units. From bottom to top, it includes a three-layer structure, the most epitaxial width is 7.2mm, and the bottom layer is made of rectangular copper film with a thickness of 17um. In the middle of the metal film, there is a quasi-I-shaped part corroded and hollowed out. The width of the hollowed out part is 1.8mm. ; On the upper side of the metal film is a layer of rectangular dielectric material, the dielectric constant is 60+0.24i, and its thickness is 0.95mm; on the upper side of the dielectric material is a layer of copper film, the thickness is 17um, and the shape of the metal film is The quasi-I shape, the metal line width is 1mm, and its absorbing performance curve is shown in Figure 5. Obviously, at the working frequency of 1.2659GHz, the absorbing performance of this structure exceeds -20dB, and its overall thickness is only 0.97mm, while the corresponding working wavelength is 239mm. Relatively speaking, its overall thickness is only 1/246 working wavelength . Compared with traditional absorbing materials, the new structure has extremely small thickness and excellent absorbing performance.

The present invention can combine a plurality of such absorbing units to construct a thin absorbing material. Usually, the operating range of such absorbing materials is between 0.5GHz and 150GHz, and can be widely used for electromagnetic isolation and stealth inside microwave devices. wait.

Although the present invention has been described with reference to the accompanying drawings and preferred embodiments, various modifications and changes will occur to those skilled in the art. Various modifications, changes, and equivalents of the present invention are covered by the content of the appended claims.

Claims (2)

1. An ultra-compact metamaterial wave-absorbing unit, characterized in that it comprises: a first metal film (1), a rectangular dielectric layer (3) is arranged on the rectangular metal film (1), and a rectangular dielectric layer (3) ) is provided with a second metal film (4), and a hollow (2) is provided on the first metal film (1), and the hollow (2) is composed of a first C-shaped hollow (21) and a second C-shaped hollow (22) and the first C-shaped hollow (21) and the second C-shaped hollow (22) are arranged back to back, and the second metal film (4) is composed of the first C-shaped metal foil (41) and the second C-shaped The metal foil (42) is formed and the first C-shaped metal foil (41) and the second C-shaped metal foil (42) are arranged back to back, and the shape of the hollow (2) and the shape of the second metal film (4) are mutually Similar shape. 2. The ultra-compact metamaterial absorbing unit according to claim 1, characterized in that the projection of the second metal film (4) on the first metal film (1) falls into the first metal film (1) Openwork (2) inside.

Images