CN110380217A - High-gain end-on-fire antenna based on artificial surface plasmon - Google Patents

Abstract

The present invention discloses a high-gain end-fire antenna based on artificial surface plasmon polaritons (Spoof Surface Plasmon Polaritons, SSPPs), which includes a dielectric substrate, an upper metal patch and a lower metal patch; the upper metal patch Located on the upper surface of the dielectric substrate, including microstrip transmission lines, tapered transition slots, SSPPs transmission lines, a part of the dipole and directors; the lower metal patch is located on the lower surface of the dielectric substrate, including the ground plane, Parts of tapered transition slots, SSPPs transmission lines, and dipoles. The structure uses artificial surface plasmon waveguide to transmit energy, uses dipoles at the terminal to achieve radiation, and introduces the director of the Yagi antenna at the end of the antenna, and uses the ground plane to replace the reflector of the Yagi antenna, thereby increasing the gain. The invention optimizes the traditional dipole end-fire antenna, has a simple design structure, increases the working bandwidth, reduces the mutual coupling between the antennas, and greatly improves the antenna gain.

Description

High Gain Endfire Antenna Based on Artificial Surface Plasmons

technical field

The invention relates to a high-gain end-fire antenna based on artificial surface plasmons, which can be used in the field of microwave technology.

Background technique

Artificial surface plasmon waveguides are considered to be an ideal choice for transmission lines in the GHz to THz region, and have attracted extensive attention from the scientific and engineering communities in recent years. The most commonly used is to use periodic trench structures to guide artificial surface plasmon waves, and based on this waveguide structure, various passive devices such as antennas, filters, and couplers have been designed. The development of artificial surface plasmon polaritons mainly depends on the radiation of SPP waves. The various radiation methods realized now open up the way for antennas based on artificial surface plasmon polaritons, but most of them are large in size and relatively complex. Therefore, we considered other radiating elements. As the most basic and commonly used antenna, dipole has been widely used in antenna engineering because of its convenient fabrication and easy integration with radio frequency circuits. However, when applied to microwaves at terahertz frequencies, the gain of the dipole is significantly lower. With the continuous application of metamaterials in different antennas, metamaterials can be used to achieve bandwidth and gain enhancement, beam focusing and frequency reconfiguration. The antenna designed in the present invention combines the metamaterial technology and the dipole direction, so that it can be used more widely.

Contents of the invention

In order to solve the technical problems raised by the above-mentioned background technology, the present invention aims to provide a high-gain end-fire antenna based on artificial surface plasmons, which solves the problem of low gain of dipole antennas and provides a basis for future research on antennas with higher gain. lay the foundation.

The present invention will be realized through the following technical solutions: a high-gain end-fire antenna based on artificial surface plasmons, the high-gain end-fire antenna is a single-layer structure, including a dielectric substrate, a top metal layer and a bottom metal layer; the top metal layer Located on the upper surface of the dielectric substrate, including microstrip transmission lines, gradient transition slots, SSPPs transmission lines, a part of the dipole, and directors; the underlying metal layer is located on the lower surface of the dielectric substrate, including ground planes, gradient transition slots , SSPPs transmission line and a part of the dipole; the microstrip transmission line feeds through the gradual transition slot and uses the SSPPs transmission line waveguide to transmit energy, and uses the dipole at the terminal to achieve energy radiation, and introduces the director of the Yagi antenna at the end of the antenna. The ground plane replaces the reflector of the Yagi antenna to increase the gain and form a high-gain end-fire antenna.

The technical scheme further defined in the present invention is:

Preferably, the transition zone between the microstrip transmission line (5) and the SSPPs transmission line (7) in the top metal layer adopts a trapezoidal tapered groove structure.

Preferably, there are a total of 8 gradient grooves, which are deepened sequentially until they are as deep as the grooves of the SSPPs transmission line.

Preferably, the SSPPs transmission line structure in the top metal layer is a comb-like periodic structure, and the height and width of each groove are the same.

Preferably, the distance between the directors at the right end of the top metal layer increases gradually from left to right, and the length gradually decreases.

Preferably, the ground plane of the underlying metal layer is a U-shaped ground plane.

Preferably, the transmission lines and dipoles in the bottom metal layer are completely symmetrical and opposite to the transmission lines and dipoles in the metal on the upper surface, that is, the shape and size are the same, and the directions are opposite.

Preferably, the dielectric substrate is an FR4 dielectric board with a dielectric constant of 2.65 and a thickness of 0.8 mm.

Compared with the prior art, the present invention adopts the above technical scheme and has the following technical effects: the high-gain endfire antenna is simple in structure, small in size and easy to integrate; compared with the traditional dipole antenna, the proposed high-gain antenna based on SSPPs Gain endfire antenna systems maintain energy integrity and minimize waveguide losses. At the same time, due to the strong confinement of artificial surface plasmons, artificial surface plasmon waveguides can provide more compact planar structures and can be fabricated with other planar devices without significant mutual coupling. Compared with existing SSPPs antennas, the structure has a smaller size. Simulation test results also show that the structure has good performance. The results show that the high-gain end-fire antenna based on SSPPs can achieve a gain of 9.5dBi when the design frequency is 6GHz.

The invention optimizes the dipole antenna, firstly, the grounding plane of the antenna is expanded, so that the radiation area at the rear end of the antenna is reflected to the front end, the radiation direction of the dipole antenna is changed and the gain of the antenna is improved; secondly, a director is introduced , which improves the directivity of the antenna and further increases the gain of the antenna, realizing a high-gain end-fire antenna.

Description of drawings

FIG. 1 is a schematic diagram of a three-dimensional structure of a high-gain endfire antenna based on artificial surface plasmons according to the present invention.

Fig. 2 is a three-dimensional exploded schematic view of the high-gain end-fire antenna based on artificial surface plasmons of the present invention.

Fig. 3 is a top view of the high-gain end-fire antenna based on artificial surface plasmons of the present invention.

Fig. 4 is the S-parameter simulation result of the high-gain end-fire antenna based on the artificial surface plasmon of the present invention.

FIG. 5 is a schematic diagram of a 2D pattern of the high-gain end-fire antenna based on artificial surface plasmons of the present invention.

The reference signs in the figure are: 1-dielectric substrate, 2-top metal layer, 3-bottom metal layer, 4-ground plane, 5-microstrip line, 6-gradient transition zone, 7-SSPPs transmission line, 8-even Pole, 9-director.

Detailed ways

Objects, advantages and features of the present invention will be illustrated and explained by the following non-limiting description of preferred embodiments.

The present invention discloses a high-gain end-fire antenna based on artificial surface plasmons, as shown in Figure 1, Figure 2 and Figure 3, the high-gain end-fire antenna is a single-layer structure, including a dielectric substrate 1 and a top layer The metal layer 2 and the bottom metal layer 3, the top metal layer 2 is arranged on the upper surface of the dielectric substrate 1, and the bottom metal layer 3 is arranged on the lower surface of the dielectric substrate 1, that is, the high-gain end-fire antenna is from top to bottom The lower layer contains the top metal layer, the dielectric substrate and the bottom metal sheet in sequence. In this technical solution, the dielectric substrate is an FR4 dielectric board with a dielectric constant of 2.65 and a thickness of 0.8 mm.

The top metal layer 2 and the bottom metal layer 3 are provided with an antenna structure, the top metal structure includes a microstrip line 5, a gradual transition zone 6, an SSPPs transmission line 7, a dipole 8 and a director 9; the bottom metal structure includes a ground plane 4. Gradient transition zone 6, SSPPs transmission line 7 and dipole 8; the antenna structure utilizes microstrip line feed, adopts SSPPs waveguide to transmit energy after passing through the gradient transition slot, and utilizes dipole to realize energy radiation at the terminal, and in The end of the antenna is introduced into the director to increase the gain and form a high-gain end-fire antenna.

The antenna structure is arranged on the upper and lower surfaces of the dielectric substrate, wherein both the tapered transition zone and the SSPPs transmission line are antisymmetric structures, that is, the transmission lines on the upper and lower surfaces have the same size and structure, and the directions are opposite.

The dipole part of the antenna structure is distributed on the upper and lower surfaces of the dielectric substrate.

The directors of the antenna structure are three metal patches, all of which are arranged on the upper surface of the dielectric substrate and located on the right side of the terminal dipole.

As shown in Figure 2, the complete antenna structure in the system is to use the microstrip line to excite the electromagnetic wave through the transition zone and then use the SSPPs waveguide to transmit energy. At the terminal, the dipole is used to realize energy radiation, and the radiation direction of the antenna is guided by the director.

The invention can smoothly realize the transformation from omnidirectional radiation to directional radiation, and greatly increase the gain of the antenna. Compared with the traditional dipole end-fire antenna, the invention makes the antenna more compact and reduces the dielectric loss.

Figure 4 is a simulation result diagram of the reflection coefficient of the high-gain end-fire antenna based on artificial surface plasmons. It can be seen intuitively from the figure that the high-gain end-fire antenna based on artificial surface plasmons of the present invention operates at 5.4GHz-6.3 In the frequency band of GHz, S ₁₁ is lower than -10dB, so the antenna can work well in the working frequency band of 5.4GHz-6.3GHz.

Figure 5 is a two-dimensional radiation pattern of a high-gain end-fire antenna based on artificial surface plasmons. It can be clearly seen from the figure that the maximum gain can reach nearly 10dBi, which shows that the increase of the director is greatly improved. the radiation gain of the antenna.

The present invention proposes a high-gain end-fire antenna based on artificial surface plasmons. Compared with traditional dipole antennas, artificial surface plasmon waveguides are used to replace traditional microstrip transmission lines, which can greatly reduce transmission loss and make electromagnetic waves bound On metal indicates spread. Then, in order to improve the radiation gain of the end-fire antenna, we loaded the director structure in the direction of the antenna terminal according to the radiation mechanism of the Yagi antenna, and extended the ground plane of the dielectric waveguide as the reflector of the Yagi antenna to enhance the radiation gain. Through the simulation test of the antenna structure, we can see that the structure has good performance. Based on the metamaterial SSPPs antenna system, when the design frequency is 6GHz, the gain can reach up to 10dBi, which is 7dBi higher than the traditional dipole endfire antenna, and has better directivity.

The above is only a specific implementation mode in the present invention, but the scope of protection of the present invention is not limited thereto. Anyone familiar with the technology can understand the conceivable transformation or replacement within the technical scope disclosed in the present invention. All should be covered within the scope of the present invention, therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (8)

1. the high-gain end-on-fire antenna based on artificial surface plasmon, it is characterised in that: the high-gain end-on-fire antenna is Single layer structure contains dielectric substrate (1), top layer metallic layer (2) and bottom metal layer (3)；The top layer metallic layer (2) is located at The upper surface of dielectric substrate (1), including microstrip transmission line (5), gradual change shape lead-over groove (6), SSPPs transmission line (7), dipole (8) a part and director (9)；The bottom metal layer (3) is located at the lower surface of dielectric substrate (1), including ground plane (4), a part of gradual change shape lead-over groove (6), SSPPs transmission line (7) and dipole (8)；Microstrip transmission line (5) feed SSPPs transmission line (7) waveguide transmission energy is used after gradual transition slot (6), realizes energy using dipole (8) in terminal Radiation introduces the director (9) of yagi aerial in the end of antenna, improves gain using ground plane, form high-gain end-fire day Line.

2. the high-gain end-on-fire antenna according to claim 1 based on artificial surface plasmon, it is characterised in that: institute Microstrip transmission line in top layer metallic layer (5) to SSPPs transmission line (7) intermediate intermediate zone is stated using trapezoidal gradual change slot structure.

3. the high-gain end-on-fire antenna according to claim 2 based on artificial surface plasmon, it is characterised in that: gradually Become slot one and share 8, successively deepen, until deep with the slot of SSPPs transmission line etc..

4. the high-gain end-on-fire antenna according to claim 1 based on artificial surface plasmon, it is characterised in that: institute Stating SSPPs transmission line structure in top layer metallic layer is pectination cycle structure, and the height and width of each groove are identical.

5. the high-gain end-on-fire antenna according to claim 1 based on artificial surface plasmon, it is characterised in that: institute Stating the director of top layer metallic layer right end, from left to right spacing is gradually increased, and length is gradually shortened.

6. the high-gain end-on-fire antenna according to claim 1 based on artificial surface plasmon, it is characterised in that: institute The ground plane for stating bottom metal layer is a U-shaped ground plane.

7. the high-gain end-on-fire antenna according to claim 1 based on artificial surface plasmon, it is characterised in that: institute State transmission line and dipole in bottom metal layer be same as above the transmission line of surface metal and dipole be it is full symmetric reversed, i.e., Shape, size are identical, contrary.

8. the high-gain end-on-fire antenna according to claim 1 based on artificial surface plasmon, it is characterised in that: institute The dielectric substrate stated is FR4 dielectric-slab, dielectric constant 2.65, with a thickness of 0.8 millimeter.