CN101656351A - Wideband Yagi aerial for half-mould substrate integrated waveguide feed - Google Patents

Abstract

The invention discloses a half-mode substrate integrated waveguide feeding broadband Yagi antenna, which comprises a dielectric substrate with metal coating on both sides. The structure includes a half-mode substrate integrated waveguide, a Yagi array antenna, a microstrip transition line and a 50-ohm microstrip output line. The half-mode substrate integrated waveguide is composed of metallized through holes, the upper metal coating of the half-mode substrate integrated waveguide and the lower metal coating of the half-mode substrate integrated waveguide. The Yagi array antenna is composed of directors, cross-feed elements on the upper and lower surfaces and parallel lines. For the convenience of testing, a microstrip transition line is designed to be connected between the half-mode substrate integrated waveguide and the 50-ohm microstrip line. The half-mode substrate integrated waveguide structure is used as the feed structure of the antenna, which realizes a balanced line structure with a phase difference of 180 degrees between the upper and lower metal surface currents, so that it can be directly connected to the Yagi array antenna. In order to increase the gain, four guides are used device, thus forming a broadband, high-gain, low-cost, low-profile printed antenna structure.

Description

Broadband Yagi Antenna with Half-mode Substrate Integrated Waveguide Feed

technical field

The invention is a broadband Yagi antenna design technology based on a novel feeding structure. The designed antenna has a working bandwidth of 22GHz-30GHz and a gain of 10dB. It includes two parts: a half-mode substrate integrated waveguide and a broadband Yagi antenna structure. By cascading the half-mode substrate integrated waveguide with the Yagi antenna, the waveguide structure feeds the Yagi antenna structure, forming a broadband antenna with simple feeding structure and wide operating bandwidth. The antenna design is based on planar printed circuit technology, which is small in size and suitable for planar high integration.

Background technique

With the rapid development of communication technology, broadband communication systems with many advantages such as low complexity, low cost, and wide operating bandwidth have been extensively researched and applied. The millimeter wave is an important and relatively late development of the electromagnetic spectrum. Millimeter waves are favored for their short wavelength, wide frequency band, quasi-light and quasi-all-weather, and have been widely used in military and civilian systems. Therefore, the application of the millimeter wave broadband communication system has great application prospects. Space Yagi array antennas are widely used in broadband communication systems. Due to their large size, they have gradually developed into printed Yagi array antennas. However, the feeding structure of millimeter-wave printed Yagi antennas has a large loss. The half-mode substrate integrated waveguide is a planar transmission line structure with low profile, low cost, wide operating bandwidth, simple design, and low loss. At the same time, the current phase difference between the upper and lower planes is 180°, which has the characteristics of a balanced line. Combining the Yagi antenna with the half-mode substrate-integrated waveguide structure can form a low-profile, low-cost, high-gain broadband printed Yagi antenna.

Contents of the invention

Technical problem: The purpose of this invention is to propose a broadband Yagi antenna fed by a half-mode substrate integrated waveguide. It has the advantages of low cost and convenient mass production, so it is suitable for applications in broadband communication systems.

Technical solution: The half-mode substrate integrated waveguide-fed Yagi antenna of the present invention is provided with an upper surface metal coating and a lower surface metal coating on both sides of the dielectric substrate, and four directors are provided on the front of the dielectric substrate. In the lower part of the director, there is a front crossed Yagi dipole unit, the front feed parallel line, the front metal metal coating of the half-mode substrate integrated waveguide, the microstrip gradient line, and the 50 ohm microstrip line are sequentially connected in series, and the feed The upper end of the parallel line is connected to the front crossed Yagi dipole unit, and the lower end of the 50 ohm microstrip line is the input port; the bottom surface of the dielectric substrate is respectively symmetrical to the front crossed Yagi dipole unit and the front feed parallel line. Cross Yagi dipole unit, bottom feed parallel line, connect the ground surface of half-mode substrate integrated waveguide and microstrip line under the bottom feed parallel line, and the antenna has a row of metallization equivalent to waveguide wall The through hole connects the ground surface of the half-mode substrate integrated waveguide and the microstrip line to the metal plating on the front side of the half-mode substrate integrated waveguide.

The front metal plating of the half-mode substrate integrated waveguide is directly connected to the front feed parallel line of the Yagi dipole array antenna, and the bottom surface of the half-mode substrate integrated waveguide and microstrip line is directly connected to the bottom surface of the Yagi dipole array antenna The feeding parallel line is connected, and finally the feeding structure of the antenna is formed. At the same time, the metallized through hole is a through hole opened on the dielectric substrate. Metal plating is connected.

Beneficial effect:

1. The antenna has broadband characteristics, which can meet the requirements of broadband microwave and millimeter wave communication systems;

2. The antenna design is simple. In the millimeter wave frequency band, the Yagi antenna is directly fed by the half-mode substrate integrated waveguide technology, which realizes the simplification, planarization and easy integration of the feeding structure.

3. The overall volume of the antenna is small, and the half-mode substrate integrated waveguide is used as the feeder, which can be easily integrated with the microwave planar circuit and is suitable for mobile miniaturized equipment;

4. All parts of the whole antenna are integrated into one body, with simple structure, all produced by PCB technology, low cost, high precision, good repeatability, suitable for mass production.

5. Low loss; the feed structure adopts a half-mode substrate integrated waveguide structure. The upper and lower metal cladding layers and the metallized through holes in the structure have evolved from the substrate integrated waveguide technology, retaining the substrate integration The inherent low loss characteristic of the waveguide; at the same time, the aspect ratio of the half-mode substrate integrated waveguide is smaller than that of the substrate integrated waveguide. Therefore, the loss of the electromagnetic wave due to the non-ideality of the medium is smaller during the propagation process, and it has better low-loss characteristics.

6. High gain: The antenna uses four directors to increase the gain.

Description of drawings

Fig. 1 is a side view of the present invention,

Fig. 2 is the top view of the present invention,

Figure 3 is a low view of the present invention,

Fig. 4 is the test reflection coefficient of the antenna of the present invention,

Fig. 5 is the antenna test gain of the present invention,

Fig. 6 is the antenna test pattern of the present invention at 28 GHz, including the main polarization pattern of the E plane, the main polarization pattern of the H plane, the cross polarization pattern of the H plane and the cross polarization pattern of the E plane.

In the above figure, there are: dielectric substrate 1, metal coating 2 on the upper surface, metal coating 3 on the lower surface, metallized through hole 4, director 5, metal coating 6 on the lower surface of the half-mode substrate integrated waveguide and microstrip line , half-mode substrate integrated waveguide upper surface metal coating 7, microstrip gradient transition line 8, 50 ohm microstrip line 9, input port 10, upper surface parallel line 11, lower surface parallel line 12, upper surface feed array antenna 13 , the lower surface feeds the array element antenna 14 .

Detailed ways

The half-mode substrate integrated waveguide-fed broadband Yagi antenna of the present invention is realized on the microwave dielectric substrate through the printed circuit board technology. The half-mode substrate integrated waveguide structure is used as the feed structure to realize the transition from the coaxial line to the Yagi array antenna.

The broadband printed Yagi array antenna consists of a dielectric substrate, two layers of metal coatings covered on the upper and lower surfaces of the dielectric substrate and a row of metallized through holes; the metal coating on the upper surface includes 50 ohm microstrip lines, microstrip gradient lines, The upper metal surface, director, antenna element and parallel lines of the half-mode substrate integrated waveguide; the lower surface metal coating contains the ground surface metal layer of the half-mode substrate integrated waveguide and microstrip line, which is cross-symmetrical with the upper surface antenna element The antenna element on the lower surface is a parallel line on the lower surface that is symmetrical to the parallel line on the upper surface; the antenna radiation unit adopts the cross element on the upper and lower surfaces; the feeder part adopts the form of a half-mode substrate integrated waveguide, and the feeder part and the antenna radiation unit pass through The parallel lines on the upper and lower surfaces are directly connected; in order to increase the gain, four directors are used; at the same time, for the convenience of testing, the microstrip gradient line is used to match the half-mode substrate integrated waveguide and the 50 ohm microstrip line. The Yagi antenna structure of the half-mode substrate integrated with waveguide feeding is shown in Figures 1-3. The dielectric substrate 1 is composed of a metal coating 2 on the upper surface, a metal coating 3 on the lower surface and a row of metallized holes 4. The upper surface metal coating 2 includes four directors 5, the upper surface metal coating 7 of the half-mode substrate integrated waveguide, the microstrip transition line 8, the 50 ohm microstrip line 9, the upper surface feeding parallel line 11, the upper surface Surface feed element antenna 13 . The lower surface metal coating 3 includes the lower surface metal coating 6 of the half-mode substrate integrated waveguide and microstrip line, the lower surface feeds the collective parallel lines 12 , and the lower surface feeds the array element antenna 14 . There is a row of metallized through holes 4 equivalent to waveguide walls on one side of the substrate. The antenna is fed by the half-mode substrate integrated waveguide, forming the current balance characteristics of the upper surface element 13 and the lower surface element 14 . At the same time, for the convenience of testing, a section of microstrip transition line 8 is matched and connected between the half-mode substrate integrated waveguide structure and the 50 ohm microstrip line 9, and one end of the half-mode substrate integrated waveguide is an input port 10. The diameter of the metallized through-hole 4 is 0.4 mm, and the distance between the centers of adjacent metallized through-holes is 0.8 mm; a metal sleeve is arranged on the inner wall of the through-hole and the metal sleeve is connected with the metal coating on both sides of the dielectric substrate connect them.

Claims (2)

1. the Yagi antenna of a half-mould substrate integrated waveguide feed, it is characterized in that this antenna is respectively equipped with the upper surface coat of metal (2) and the lower surface coat of metal (3) on the two sides of dielectric substrate (1), be provided with four directors (5) in the front of dielectric substrate (1), be provided with the positive Yagi spark gap doublet unit (13) that intersects in the bottom of director (5), front feed parallel lines (11), the front metal coat of metal (7) of half module substrate integrated wave guide, little band transition line (8), 50 ohm microstrip (9) order is connected in series, the positive Yagi spark gap doublet unit (13) that intersects of the last termination of feed parallel lines (11), the lower end of 50 ohm microstrip (9) is input port (10);

Be provided with in the bottom surface of dielectric substrate (1) respectively and intersect the bottom surface of Yagi spark gap doublet unit (13), front feed parallel lines (11) symmetry with the front and intersect Yagi spark gap doublet unit (14), bottom surface feed parallel lines (12); the ground surface (6) that connects half module substrate integrated wave guide and microstrip line in the bottom of bottom surface feed parallel lines (12), this antenna has row's equivalence connects ground surface (6) half module substrate integrated wave guide of half module substrate integrated wave guide and microstrip line for the plated-through hole of wave guide wall (4) the front metal coat of metal (7) simultaneously.

2. the Yagi antenna of half-mould substrate integrated waveguide feed according to claim 1; the front metal coating (7) that it is characterized in that half module substrate integrated wave guide directly is connected with the front feed parallel lines (11) of the Yagi spark gap array antenna of dipoles; the bottom surface ground surface (6) of half module substrate integrated wave guide and microstrip line directly is connected with the bottom surface feed parallel lines (12) of the Yagi spark gap array antenna of dipoles; form the feed structure of this antenna at last; plated-through hole (4) is to offer through hole on dielectric substrate (1) simultaneously, and this plated-through hole (4) couples together with the upper surface coat of metal (2) and the lower surface coat of metal (3) that are overlying on dielectric substrate (1) bilateral.

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