CN107645070B - Multi-beam antenna based on one-dimensional microwave planar lens and double-gradient-groove antenna linear array - Google Patents

Abstract

A multi-beam antenna based on a one-dimensional microwave plane lens and a double gradient slot antenna line array is composed of a double gradient groove antenna line array (1) and a one-dimensional microwave plane lens (2). One-dimensional microwave plane lens consists of four layers of artificial electromagnetic material surface (3), printed on it

As a phase shifting unit (8) and a fixing column (4), the double gradient slot antenna array (1) is composed of a double gradient slot antenna unit (9) and is fixed on the plexiglass backplane (7). The antenna is fed with a substrate-integrated waveguide (6), which can be integrated and connected with other microwave circuits. The one-dimensional microwave flat lens (2) and the plexiglass backplane (7) are connected by long nylon support columns (5). The radiation phase center line of the double gradient slot antenna array (1) coincides with the focal line of the one-dimensional microwave plane lens (2), so as to achieve the best focusing effect. The invention can realize the high-gain and large-angle spatial scanning function, and has the advantages of high integration and simple fabrication and low cost.

Description

Multi-beam antenna based on one-dimensional microwave plane lens and double gradient slot antenna array

technical field

The invention relates to a high-gain multi-beam antenna formed by loading a microwave lens based on artificial electromagnetic materials in front of a double-gradient-slot antenna line array, and has a large-angle beam scanning function while achieving high-gain performance of the antenna, belonging to the field of microwave technology. .

Background technique

With the explosive growth of data volume in wireless communication, in order to increase the data transmission bandwidth, millimeter wave communication technology is required. In order to improve the signal-to-interference-noise ratio of the system, reduce the Doppler effect, and improve data security, a high-gain millimeter-wave antenna needs to be used. In order to search for links, a high-gain multi-beam antenna with a certain spatial coverage becomes the core part of Massive MIMO (Multiple Input Multiple Output) technology. This multi-beam antenna can make multiple beams exist at the same time and work independently, which can improve frequency reuse and system capacity.

There are three common design methods for multi-beam antennas. One is to realize multiple beams by passive means, such as using Butler matrix or Norton matrix to feed the array antenna, and the other is to realize multi-beam by defocusing the lens. The disadvantage is that the coverage of the antenna is limited by the number of waves and the beam width, and it is difficult to implement high-order matrices. The other is to use active circuits to achieve multi-beam, mainly analog phased arrays and digital multi-beam arrays. The disadvantage is that the number of channels is large and the cost is high. The invention uses the one-dimensional microwave lens and the double gradient slot antenna line array for the first time, successfully realizes the large-angle high-gain multi-beam full coverage, and reduces the number of channels and the cost of the multi-beam antenna.

SUMMARY OF THE INVENTION

Technical problem: The purpose of the present invention is to provide a multi-beam antenna based on a one-dimensional microwave plane lens and a double gradient slot antenna array. This kind of antenna can realize the characteristics of high gain and wide angle scanning in the working frequency band. This antenna utilizes the degree of freedom of the antenna linear array to control the beam pointing and the characteristics of the microwave lens to improve the antenna gain. The combination of high gain and multi-beam characteristics reduces the number of channels and cost of the multi-beam antenna, and is simple to process and compact. , stable performance, conducive to integration.

Technical solution: A multi-beam antenna based on a one-dimensional microwave plane lens and a double-graded slot antenna array of the present invention consists of a double-graded slot antenna array for radiating signals and a double-graded slot antenna array parallel to the plane. The one-dimensional microwave plane lens is composed of an artificial electromagnetic material surface and a nylon fixed column. The artificial electromagnetic material surface has multiple layers, which are separated by nylon fixed columns. The double gradient slot antenna line array is composed of a double gradient slot antenna. The units are arranged in a row and fixed on the backplane. The one-dimensional microwave plane lens and the backplane are connected by a support column. The double gradient slot antenna unit is fed by a substrate integrated waveguide.

的铜箔作为移相单元。The surface of the artificial electromagnetic material has multiple layers, and the plane of each layer is provided with

The copper foil is used as the phase shifting unit.

The substrate-integrated waveguide for feeding uses a dielectric plate with a dielectric constant of 2.2 and a thickness of 0.508 mm, and the width is less than or equal to 7 mm in a frequency range with a center frequency greater than 24.25 GHz.

The double-graded-slot antenna line array for radiating signals is composed of double-graded-slot antenna units arranged in a linear array. The unit is printed on a dielectric plate with a thickness of 0.508 mm and a dielectric constant of 2.2. The radiating metal spiral arms satisfy the exponential change, and the beam width of the pattern is greater than 90 degrees in the horizontal plane and less than 45 degrees in the vertical plane.

形条带作为移相单元，条带宽度为0.2毫米；其分布特点为在与波束扫描的水平维度呈连续排布，在垂直维度上呈现变化排布，组成人工电磁材料表面，四层人工电磁材料表面构成一维微波平面透镜。The surface of the artificial electromagnetic material is fabricated on a printed board with a thickness of 0.203 mm and a dielectric constant of 3.55.

The strip is used as a phase-shifting unit, and the strip width is 0.2 mm; its distribution is characterized by a continuous arrangement in the horizontal dimension of the beam scanning, and a changing arrangement in the vertical dimension, forming an artificial electromagnetic material surface, four layers of artificial electromagnetic The surface of the material constitutes a one-dimensional microwave plane lens.

The distance between the one-dimensional microwave plane lens and the phase center line of the double gradient groove antenna array is the focal length of the one-dimensional microwave plane lens.

The working principle is: in the working frequency band, by controlling the radiation phase of each element of the double-graded slot antenna line array, a fan beam directed in multiple directions is generated, that is, the beam is narrowed in the horizontal direction and wide in the vertical direction. When passing through a one-dimensional lens consisting of an artificial electromagnetic material surface, the beam is narrowed in the vertical direction, but not affected in the horizontal direction. This achieves a pencil beam that can be directional scanned in the horizontal dimension. From the point of view of wavefront, the spherical wavefront radiated by the double gradient slot antenna unit makes the radiation wavefront into a cylindrical shape by forming a linear array, and then converts the cylindrical beam into a plane wave through a one-dimensional microwave lens. Thus, the gain of the entire antenna system is improved. In general, the present antenna achieves high antenna gain and can cover a large scanning angle in the horizontal direction, thereby providing a feasible antenna solution for Massive Multiple Input Multiple Output (MIMO).

Beneficial effects: The high-gain multi-beam antenna based on one-dimensional microwave flat lens and double gradient slot antenna array has the following advantages:

a. This new type of antenna well achieves the performance of simultaneous high gain and antenna pattern direction pointing to space scanning. This antenna can be used in conjunction with phased array technology and digital multi-beam technology to achieve spatial diversity, frequency reuse, etc. Function.

b. This new type of antenna uses a plane microwave lens composed of artificial electromagnetic material surface, and the double gradient slot antenna is made by ordinary PCB process, which is small in size and low in cost.

c. The double tapered slot antenna array used in this new antenna is composed of double tapered slot antenna units. This double tapered slot antenna is fed by the substrate integrated waveguide, which is easy to integrate with other microwave circuits, and has good anti-interference performance and insertion loss. Small.

d. Compared with the traditional phased array or all-digital multi-beam antenna, the present invention can reduce the number of channels for spatial scanning, greatly reducing the complexity and cost. Compared with the traditional lens multi-beam antenna, the present invention can greatly improve the spatial coverage, freely control the beam direction and the number of beams, and improve the performance.

Description of drawings

作为移相单元。固定柱4，支撑柱5，基片集成波导6，背板7，双渐变槽天线单元9。FIG. 1 is a top view of the schematic structure of the present invention. In the picture: double gradient slot antenna line array 1, microwave flat lens 2, artificial electromagnetic material surface 3, printed on it

as a phase shifting unit. Fixed column 4 , support column 5 , substrate integrated waveguide 6 , backplane 7 , double gradient slot antenna unit 9 .

Figure 2 is a side view of the present invention.

Figure 3 is a schematic diagram of the overall structure of the present invention. W _len is the width of the microwave plane lens, H _len is the height of the micro-plane, W _p is the width of the metal strip of the phase-shifting unit, D ₀ is the distance between two adjacent double-graded slot antenna units, and W _a is the double-gradient The width of the slot antenna unit, L _a is the length of the double tapered slot antenna unit, W _siw is the width of the substrate integrated waveguide, R _via is the radius of the substrate integrated waveguide hole, and d _p is the hole of two adjacent through holes The center distance, F is the distance from the microwave plane lens to the phase center line of the double gradient groove antenna array, L ₀ is the length of nylon fixed, and L ₁ is the length of the nylon support column. h _l is the thickness of the dielectric layer on the surface of the artificial electromagnetic material, h _a is the thickness of the dielectric plate of the double gradient slot antenna unit, ε _r1 is the dielectric constant of the artificial electromagnetic material surface dielectric plate, ε _ra is the dielectric constant of the double gradient slot antenna unit dielectric plate .

Figure 4 is a rear perspective view of the planar microwave lens of the present invention. The figure also includes a phase shifting unit 8 .

FIG. 5 is a partial view of the planar microwave lens of the present invention.

Figure 6 is a side perspective view of the dual tapered slot antenna unit of the present invention.

FIG. 7 is a test result of the return loss of the feed port of a double tapered slot antenna unit according to the present invention.

FIG. 8 is a simulation result of the pattern of a double tapered slot antenna unit according to the present invention.

FIG. 9 is a schematic diagram of a test method using a digital multi-beam test platform according to the present invention.

FIG. 10 is a multi-beam pattern test result synthesized by the present invention using digital multi-beam technology at 26 GHz.

Detailed ways

条带构成，条带宽为0.2毫米，

中间臂长为3.1毫米，四周的条带臂长根据移相值决定。相邻两层人工电磁材料表面之间的距离为2.6毫米。微波平面透镜的口径大小为324毫米×162毫米。在天线系统组合上，双渐变槽天线线阵辐射口径正对一维微波平面透镜，且居中放置，一维微波平面透镜的焦线与双渐变槽天线阵列的相位中心线重合从而达到最佳聚焦效果。各层人工电磁材料表面之间的距离，由尼龙固定柱保持，一维微波平面透镜和双渐变槽天线线阵之间的距离由机玻璃背板与尼龙支撑柱固定和稳定保持。The multi-beam antenna based on the one-dimensional microwave plane lens and the double gradient slot antenna line array of the present invention is a multifunctional antenna synthesized by two independent structures. One-dimensional microwave plane lens is a plane lens composed of four separate artificial electromagnetic material surfaces. Phase-shifting units are printed on the surface of each layer, and these phase-shifting units are arranged in a column shape, that is, they are continuously arranged in the horizontal direction and arranged in a vertical direction according to different phase-shifting requirements. Nylon fixed posts are used between the surfaces of the four layers of artificial electromagnetic material to maintain the air separation distance to achieve resonance. The double-graded-slot antenna line array consists of 16 double-graded-slot antenna units linearly arranged in the horizontal direction. The spacing between the double tapered slot antenna elements is 6 mm, and the tapered slot line has an exponential relationship with the distance from the center line. The opening widths of the double gradient grooves are both 12.8 mm, and the distances between the two gradient grooves and the feeding substrate integrated waveguide are 8.72 mm and 14.08 mm, respectively. The graded groove and the feed substrate integrated waveguide are fabricated on a microwave printed circuit board. The sheet is Ro5880 with a dielectric constant of 0.22, a thickness of 0.508 mm, and a metallized via diameter of 0.3 mm. A fed substrate-integrated waveguide is used to interface with each channel's microwave circuitry and beamforming network. The surface of the artificial electromagnetic material is made of a microwave printed circuit board, and the plate is Ro4003C with a dielectric constant of 3.55 and a thickness of 0.203 mm. The phase-shifting unit on the surface of the artificial electromagnetic material consists of a Jerusalem cross printed on the plate.

Strip construction, strip width is 0.2 mm,

The length of the middle arm is 3.1 mm, and the length of the surrounding strip arms is determined according to the phase shift value. The distance between the surfaces of two adjacent layers of artificial electromagnetic material is 2.6 mm. The aperture size of the microwave plane lens is 324 mm × 162 mm. In the antenna system combination, the radiation aperture of the double-graded slot antenna line array is facing the one-dimensional microwave plane lens, and is placed in the center. Effect. The distance between the surfaces of the artificial electromagnetic materials of each layer is maintained by nylon fixed columns, and the distance between the one-dimensional microwave plane lens and the double gradient slot antenna array is fixed and stably maintained by the plexiglass backplane and the nylon support column.

形条带印制在对应位置，组成人工电磁材料表面，然后在印制板周围通孔，将四层人工电磁材料表面通过尼龙柱固定，使各层之间的距离保持精确和稳定，完成平面微波透镜的制作。在印制板上印制双渐变槽天线单元以及基片集成波导，在一块有机玻璃板上开槽，将16个双渐变槽天线单元从槽中完全伸出，并稳定固定的距离。按照设计的微波透镜的焦距确定尼龙柱的长度，将微波透镜固定在有机玻璃板，使得天线阵列正对微波平面透镜中心。微波平面透镜所包括的四层人工电磁材料表面之间的间距，微波透镜到有机玻璃板之间的距离，有机玻璃板的固定位置，都需要精确控制，直接影响天线性能。最后，将天线的16个基片集成波导馈电端口与微波接口相连，或者直接将微波电路集成在馈电端口上。本发明整个结构都是普通机械加工和普通的PCB工艺实现，制作简单，成本低廉。The manufacturing process of the present invention is as follows: first, determine the phase-shift value required by the corresponding position phase-shifting unit by calculation;

The shape strips are printed at the corresponding positions to form the surface of the artificial electromagnetic material, and then through holes are formed around the printed board, and the surface of the four layers of artificial electromagnetic material is fixed by the nylon column, so that the distance between the layers is kept accurate and stable, and the plane is completed. Fabrication of Microwave Lenses. The dual gradient slot antenna unit and the substrate integrated waveguide are printed on the printed board, a plexiglass plate is slotted, and the 16 double gradient slot antenna units are completely extended from the slot, and the distance is stable and fixed. The length of the nylon column is determined according to the focal length of the designed microwave lens, and the microwave lens is fixed on the plexiglass plate so that the antenna array faces the center of the microwave plane lens. The distance between the surfaces of the four layers of artificial electromagnetic materials included in the microwave plane lens, the distance between the microwave lens and the plexiglass plate, and the fixed position of the plexiglass plate need to be precisely controlled, which directly affects the antenna performance. Finally, the 16 substrate-integrated waveguide feeding ports of the antenna are connected to the microwave interface, or the microwave circuit is directly integrated on the feeding ports. The whole structure of the present invention is realized by common machining and common PCB technology, and the manufacturing is simple and the cost is low.

We have realized the high-gain multi-beam antenna based on one-dimensional microwave flat lens and double gradient slot antenna array introduced above in the 26GHz band. , 4) as follows:

Claims (2)

1. a kind of multi-beam antenna based on one-dimensional microwave plane lens and double gradient slot antenna linear array, it is characterized in that this multi-beam antenna is used for the double gradient groove antenna linear array (1) of the phased form of radiation signal and with The double gradient slot antenna array (1) is composed of a one-dimensional microwave plane lens (2) arranged parallel to the plane, wherein the one-dimensional microwave plane lens (2) is composed of an artificial electromagnetic material surface (3) whose unit phase distribution varies only in one dimension, and A nylon fixing column (4) is formed, and the artificial electromagnetic material surface (3) has multiple layers, which are separated by nylon fixing columns (4) respectively; the double gradient slot antenna line array (1) is arranged by double gradient slot antenna units (9) A row is formed and fixed on the backplane (7), the one-dimensional microwave flat lens (2) and the backplane (7) are connected by a support column (5), and the double gradient slot antenna unit (9) uses a substrate integrated waveguide ( 6) Feeding; The surface (3) of the artificial electromagnetic material has multiple layers, and the plane of each layer is provided with

The copper foil is used as the phase shifting unit (8); The substrate-integrated waveguide (6) for feeding uses a dielectric plate with a dielectric constant of 2.2 and a thickness of 0.508 mm, and the width is less than or equal to 7 mm in a frequency range where the center frequency is greater than 24.25 GHz; The double-graded-slot antenna linear array (1) for radiating signals is composed of double-graded-slot antenna units (9) arranged in a linear array, and the spacing between adjacent double-graded-slot antenna units (9) is 1/2 to work. From wavelength to full wavelength, the double gradient slot antenna unit (9) is printed on a dielectric plate with a thickness of 0.508 mm and a dielectric constant of 2.2. The radiating metal spiral arm satisfies the exponential change. The vertical plane is less than 45 degrees; The artificial electromagnetic material surface (3) is fabricated on a printed board with a thickness of 0.203 mm and a dielectric constant of 3.55.

The strip is used as a phase-shifting unit (8), and the width of the strip is 0.2 mm; its distribution characteristic is that it is continuously arranged in the horizontal dimension of the beam scanning, and changes in the vertical dimension, forming the surface of the artificial electromagnetic material (3 ), and the surface (3) of the four-layer artificial electromagnetic material constitutes a one-dimensional microwave plane lens (2). 2. The multi-beam antenna based on one-dimensional microwave plane lens and double gradient groove antenna line array according to claim 1, it is characterized in that described one-dimensional microwave plane lens (2) and double gradient groove antenna array (1) The distance of the phase center line is the focal distance of the one-dimensional microwave plane lens (2).

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