CN112909527B

CN112909527B - High-gain anti-sufficient Vivaldi antenna

Info

Publication number: CN112909527B
Application number: CN202110105027.7A
Authority: CN
Inventors: 李俊; 王彦杰
Original assignee: South China University of Technology SCUT
Current assignee: South China University of Technology SCUT
Priority date: 2021-01-26
Filing date: 2021-01-26
Publication date: 2021-12-24
Anticipated expiration: 2041-01-26
Also published as: CN112909527A

Abstract

The invention discloses a high-gain antipodal Vivaldi antenna, relates to the field of microwave antenna design, and aims to solve the problem of insufficient antenna gain in the prior art. The antenna comprises a bottom layer antenna board and a top layer antenna board which are arranged on two sides of a medium substrate; the feeding parts of the bottom layer antenna board and the top layer antenna board are overlapped and loaded with corresponding feeding structures; the bottom antenna plate is provided with a bottom reverse foot, and the top antenna plate is provided with a top reverse foot; the bottom radiation edge of the bottom layer reverse foot close to the top layer reverse foot is a linear edge, the top radiation edge of the top layer reverse foot close to the bottom layer reverse foot is a linear edge, and the top radiation edge and the bottom radiation edge are of a symmetrical structure. The advantage is that the gain can be improved without changing the size of the original exponential type inverted-foot Vivaldi antenna. The improved high-gain ultra-wideband Vivaldi antenna has the advantages of simple structure, easiness in processing, low cost and the like, and provides a new idea for enhancing the gain of end-fire antennas such as Vivaldi antennas and the like. The arrangement of the bottom layer metal via hole and the top layer metal via hole can further improve the gain effect.

Description

High-gain anti-sufficient Vivaldi antenna

Technical Field

The invention relates to the field of microwave antenna design, in particular to a high-gain antipodal Vivaldi antenna.

Background

The millimeter wave antenna is an important module in a 5G communication radio frequency chip, is widely applied to automobile radars, precise guidance, satellite communication and the like, and further enters the field of civil communication in the future. In recent years, China invests huge resources to develop the scientific frontier research of radio astronomy and the development of large radio astronomical telescopes. The sky speed of the radio telescope is in direct proportion to the bandwidth of the ultra-wideband antenna of the phased array feed source. The Vivaldi antenna is used as an ultra-wideband antenna, has the advantages of miniaturization, high gain, easiness in processing and the like, and is widely used as an ultra-wideband antenna array element to design an ultra-wideband phased array antenna. For example, westerberg synthetic aperture telescope in the netherlands uses Vivaldi antennas as phased array antenna elements.

With the continuous enhancement of comprehensive national strength and the rapid promotion of technological level, the technical scheme of adopting the ultra-wideband Vivaldi antenna as an antenna array element is oriented to the development requirements and engineering application of radio astronomical telescopes in China, and is necessary for researching a high-gain miniaturized Vivaldi antenna from the research of solving the technical theory and the key technology of a radio telescope phase array feed source of a major scientific instrument in China around the key technical indexes of a superconducting receiver for radio astronomical use. The Vivaldi antenna can be easily printed on a PCB (printed Circuit Board) and has a simple structure, so that the Vivaldi antenna can be applied to radio astronomical telescopes and is also designed and used in a large number of related research fields such as ultra-wideband systems, 5G base station antennas and the like.

The structure is generally shown in fig. 1, the bottom layer antenna board 10 and the top layer antenna board 20 are respectively disposed on two sides of the dielectric substrate, and the feeding portions of the bottom layer antenna board 10 and the top layer antenna board 20 are overlapped and load the corresponding feeding structures. Wherein the dielectric substrate is not represented in the figures as a well-known design. The upper end of the bottom antenna board 10 extends upward and turns to one side, forming a bottom foot 11. The top antenna board 20 extends upward at its upper end and turns to the other side, forming a top back leg 21 opposite the bottom back leg 11. The corresponding edges of the two opposite feet are radiation edges, and the two radiation edges both meet the exponential change curve. The corresponding edges of the two antenna boards far away from the radiating edge are arc-shaped and smoothly transited to the feeding part. A common antenna size profile is M × N, where M is 14mm and N is 29 mm. The physical dimension of the antenna directly affects the applied device circuit design, and how to improve the gain without changing the original exponential back-up Vivaldi antenna size is a technical difficulty in the industry.

Disclosure of Invention

The present invention aims to provide a high-gain antipodal Vivaldi antenna to solve the above problems of the prior art.

The high-gain antipodal Vivaldi antenna comprises: the antenna comprises a bottom layer antenna plate arranged on the lower side surface of a dielectric substrate and a top layer antenna plate arranged on the upper side surface of the dielectric substrate; the feeding parts of the bottom layer antenna board and the top layer antenna board are overlapped and loaded with corresponding feeding structures; the upper end of the bottom antenna plate extends upwards and deflects to one side to form a bottom-layer back foot, and the upper end of the top antenna plate extends upwards and deflects to the other side to form a top-layer back foot; the bottom radiation edge of the bottom layer reverse foot close to the top layer reverse foot is a linear edge, the top radiation edge of the top layer reverse foot close to the bottom layer reverse foot is a linear edge, and the top radiation edge and the bottom radiation edge are of a symmetrical structure.

The arc edge of the bottom layer radiation edge far away from the bottom layer radiation edge is provided with a plurality of bottom layer metal through holes, and the arc edge of the top layer radiation edge far away from the top layer radiation edge is provided with a plurality of top layer metal through holes.

The distance between the bottom metal through holes is D, and the distance between the top metal through holes is D.

The diameters of the bottom layer metal via holes and the top layer metal via holes are in the range of [0.2mm,0.4mm ], and preferably 0.3 mm.

The distance D is in the range of [0.34mm,0.55mm ], preferably 0.45 mm.

The high-gain antipodal Vivaldi antenna has the advantage that the gain can be improved without changing the size of the original exponential type antipodal Vivaldi antenna. The improved high-gain ultra-wideband Vivaldi antenna has the advantages of simple structure, easiness in processing, low cost and the like, and provides a new idea for enhancing the gain of end-fire antennas such as Vivaldi antennas and the like. The arrangement of the bottom layer metal via hole and the top layer metal via hole can further improve the gain effect.

Drawings

Fig. 1 is a schematic diagram of a structure of a transpodal Vivaldi antenna in the prior art.

Fig. 2 is a schematic structural diagram of a first embodiment of the high-gain antipodal Vivaldi antenna according to the present invention.

Fig. 3 is a schematic structural diagram of a second embodiment of the high-gain antipodal Vivaldi antenna according to the present invention.

Fig. 4 is a rear view of fig. 3.

Fig. 5 is a comparison graph of the inverted-footed Vivaldi antenna gain simulation for three different configurations.

Fig. 6 is a comparison graph of simulation of the antipodal Vivaldi antenna S11 for three different configurations.

Fig. 7, fig. 8 and fig. 9 are graphs comparing normalized radiation modes of E planes of three different structures of antipodal Vivaldi antennas.

Fig. 10, fig. 11 and fig. 12 are H-plane normalized radiation pattern comparison diagrams of three different structures of antipodal Vivaldi antennas.

Reference numerals: 10-a bottom layer antenna board, 11-a bottom layer reverse foot, 12-a bottom layer radiation edge and 13-a bottom layer metal through hole; 20-top antenna plate, 21-top reverse leg, 22-top radiating edge, 23-top metal via.

Detailed Description

Example one

As shown in fig. 2, the high-gain antipodal Vivaldi antenna according to the present invention includes: a bottom layer antenna plate 10 arranged on the lower side of the dielectric substrate and a top layer antenna plate 20 arranged on the upper side of the dielectric substrate. The feeding portions of the bottom antenna panel 10 and the top antenna panel 20 overlap and load the corresponding feeding structures. The upper end of the bottom antenna plate 10 extends upward and is biased to one side to form a bottom counter-foot 11, and the upper end of the top antenna plate 20 extends upward and is biased to the other side to form a top counter-foot 21. The bottom radiation edge 12 of the bottom reflection foot 11 close to the top reflection foot 21 is a linear edge, the top radiation edge 22 of the top reflection foot 21 close to the bottom reflection foot 11 is a linear edge, and the top radiation edge 22 and the bottom radiation edge 12 are of a symmetrical structure.

The linear radiation edge is improved from the exponential radiation edge in the prior art, the gain is improved, and the principle is as follows: by changing the curvature of the radiating edge of the antenna, the current in the end-fire direction is enhanced, and the radiation performance of the antenna is effectively improved.

Example two

As shown in fig. 3 and 4, the main difference with respect to the first embodiment is that the bottom layer feet 11 are provided with a plurality of bottom layer metal vias 13 at the arc-shaped edge far from the bottom layer radiation edge 12, and the top layer radiation edge 22 is provided with a plurality of top layer metal vias 23 at the arc-shaped edge far from the top layer radiation edge 22. The distance between the bottom metal via holes 13 is the distance D, and the distance between the top metal via holes 23 is also the distance D. The distance D is in the range of [0.34mm,0.55mm ], preferably 0.45 mm. The diameters of the bottom metal vias 13 and the top metal vias 23 are in the range of [0.2mm,0.4mm ], preferably 0.3 mm.

The bottom metal via 13 extends upward from the bottom antenna board 10 through the dielectric substrate. The top metal via 23 extends downward from the top antenna board 20 through the dielectric substrate.

The principle that the gain can be further improved by adding the bottom layer metal via 13 and the top layer metal via 23 on the basis of the first embodiment is as follows: in the process of outward radiation of electromagnetic waves, the larger the caliber is, the larger the outward loss power is, and much energy of the original antenna in radiation is lost in the caliber of an outer layer. The via hole structure can enable the radiated energy of the antenna to be more uniform and the directional diagram to be better.

Simulation test

The present invention has been separately subjected to simulation tests for three different structures of antipodal Vivaldi antennas, as shown in fig. 5 to 12. Wherein, the explicit antenna is an antenna structure with a conventional Exponential radiating edge, the Linear antenna is an antenna structure with a Linear radiating edge only and no metal via hole as described in the first embodiment, and the Improved Linear antenna is an antenna structure with a Linear radiating edge and a metal via hole as described in the second embodiment.

The simulation parameters are set as follows: the length is 29mm and the width is 14 mm. The dielectric substrate used was Rogers 5880, which had a dielectric constant of 2.2, a loss tangent of 0.0019, and a thickness of 0.8 mm. The Improved linear antenna is selected from the preferred values of example two.

As can be seen from fig. 5 and 6, compared to the exponential radiating edge antenna, the antenna gain in the first embodiment is 10.6 ± 0.4dBi, and the average gain of the antenna is improved by more than 1.2dBi at a frequency of 35-45GHz and a reflection coefficient of less than-10 dB. The gain of the antenna in the second embodiment is 11.4 +/-0.7 dBi, the frequency and the reflection coefficient of 35-45GHz are less than-10 dB, and the average gain of the antenna is improved by more than 2 dBi.

According to the plane E normalized radiation pattern comparison in fig. 7 to 9 and the plane H normalized radiation pattern comparison in fig. 10 to 12, it can be seen that as the antenna is improved step by step, the main lobe of the antenna becomes better and better in directivity, the rear lobe becomes smaller and smaller, and the energy is mainly concentrated in the main lobe direction.

It will be apparent to those skilled in the art that various other changes and modifications may be made in the above-described embodiments and concepts and all such changes and modifications are intended to be within the scope of the appended claims.

Claims

1. A high gain antipodal Vivaldi antenna comprising: a bottom layer antenna plate (10) arranged on the lower side surface of the dielectric substrate and a top layer antenna plate (20) arranged on the upper side surface of the dielectric substrate; the feeding parts of the bottom layer antenna plate (10) and the top layer antenna plate (20) are overlapped and loaded with corresponding feeding structures; the upper end of the bottom layer antenna plate (10) extends upwards and is deflected to one side to form a bottom layer reverse foot (11), and the upper end of the top layer antenna plate (20) extends upwards and is deflected to the other side to form a top layer reverse foot (21); the novel foot sole is characterized in that a bottom radiation edge (12) of the bottom layer foot sole (11) close to the top layer foot sole (21) is a linear edge, a top radiation edge (22) of the top layer foot sole (21) close to the bottom layer foot sole (11) is a linear edge, and the top radiation edge (22) and the bottom radiation edge (12) are of a symmetrical structure;

the arc-shaped edge of the bottom layer reverse foot (11) far away from the bottom layer radiation edge (12) is provided with a plurality of bottom layer metal through holes (13), and the arc-shaped edge of the top layer radiation edge (22) far away from the top layer radiation edge (22) is provided with a plurality of top layer metal through holes (23).

2. The high-gain antipodal Vivaldi antenna as claimed in claim 1, wherein the pitch of the bottom metal vias (13) is distance D, and the pitch of the top metal vias (23) is distance D.

3. The high-gain antipodal Vivaldi antenna as claimed in claim 2, wherein the diameter of the bottom metal vias (13) and the top metal vias (23) ranges from [0.2mm,0.4mm ].

4. A high gain antipodal Vivaldi antenna according to claim 3, characterized in that the diameter of the bottom layer metal vias (13) and the top layer metal vias (23) is 0.3 mm.

5. The high-gain antipodal Vivaldi antenna as claimed in claim 4, wherein the distance D is in the range of [0.34mm,0.55mm ].

6. The high gain antipodal Vivaldi antenna according to claim 2, characterized in that said distance D is 0.45 mm.