A high-gain directional broadband antenna

Abstract

The application discloses a high-gain directional broadband antenna, which comprises a metal grounding plate, a radiation layer, a feeding patch and an air medium layer; the radiation layer comprises first and second asymmetric radiation metal patches; and the feeding patch is located between the first and second radiation metal patches. The application adopts two asymmetric first and second radiation metal patches, so that the resonant frequencies of the two patch antennas have a certain difference; the metal radiation antenna is connected with the metal grounding plate through a certain number of metal short-circuit columns, so that the radiation of the radiation antenna close to the middle feeding patch is enhanced; the difference between the resonant frequencies of the two antennas is controlled by changing the position of the middle feeding patch; meanwhile, the introduction of the gap between the feeding patch and the radiation metal patch can introduce capacitance to improve the impedance characteristics of the antenna, so that the total bandwidth of the antenna is widened.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of unmanned aerial vehicle antennas, and particularly relates to a high-gain directional broadband antenna. BACKGROUND

[0002] Nowadays, as one of the key technologies in the field of wireless communication, a broadband antenna has a wide application in the fields of communication, radar, satellite navigation and the like. With the rapid development of science and technology in the world and the continuous development of communication technology, the performance requirements for the broadband antenna are getting higher and higher, especially in the broadband characteristics such as the gain of the antenna, the antenna pattern and the standing wave ratio of the antenna. Generally, the bandwidth of a patch antenna is about 3%, and therefore, it is crucial to study the patch antenna of super wideband for the development of the field of wireless communication.

[0003] Due to the inherent high Q value attribute of the microstrip patch antenna, it is a key challenge to widen the bandwidth thereof. To directly deal with this challenge, the common strategies include increasing the thickness of the dielectric substrate of the antenna or selecting a dielectric material with a lower dielectric constant. These measures aim to optimize the electromagnetic performance of the antenna, so as to expand the working bandwidth thereof.

[0004] At present, the common ways to realize the broadband include loading a parasitic unit and adopting a multi-layer patch. However, the method of loading a parasitic unit will expand the horizontal cross section of the antenna, and the method of adopting a multi-layer patch will expand the vertical cross section of the antenna, which will occupy a large part of the space and increase the weight of the antenna, thereby increasing the load of the unmanned aerial vehicle. SUMMARY

[0005] The application aims to overcome the shortcomings of the prior art, and provides a high-gain directional broadband antenna to meet the requirements of the field of wireless communication for the broadband and high-gain characteristics of the antenna, and solve the problems of the narrow bandwidth and large size of the conventional patch antenna.

[0006] To achieve the above object, the application provides the following scheme.

[0007] A high-gain directional broadband antenna comprises a metal grounding plate, a radiation layer, a feed patch, and an air dielectric layer located between the metal grounding plate and the radiation layer.

[0008] The radiation layer comprises a first radiation metal patch and a second radiation metal patch in an asymmetric structure.

[0009] The feed patch adopts a coaxial line feeding section, which is located between the first radiation metal patch and the second radiation metal patch. The two ends of the feed patch are respectively provided with a gap from the first radiation metal patch and the second radiation metal patch. A feed metal column is arranged on the feed patch, which is used to connect the feed patch and the metal grounding plate.

[0010] The first radiating metal patch, the second radiating metal patch and the metal ground plate are respectively provided with a group of metal shorting post arrays.

[0011] Further, the first radiating metal patch is provided with a first gap on a rectangular metal, and a first microstrip transmission line is arranged in the first gap; the first gap is an integral structure including a rectangular gap and an isosceles trapezoidal gap; the long side of the rectangular gap coincides with the upper base of the isosceles trapezoidal gap, and the lower base of the isosceles trapezoidal gap faces the second radiating metal patch.

[0012] The first microstrip transmission line is a ladder-shaped metal strip on both sides.

[0013] Further, the second radiating metal patch is provided with a second gap on a rectangular metal, and a second microstrip transmission line is arranged in the second gap; the second gap is an integral structure including a rectangular gap and an isosceles trapezoidal gap, the long side of the rectangular gap coincides with the upper base of the isosceles trapezoidal gap, and the lower base of the isosceles trapezoidal gap faces the first radiating metal patch.

[0014] The second microstrip transmission line is a metal strip.

[0015] Further, the center of the first microstrip transmission line, the center of the second microstrip transmission line and the center of the feeding patch are located on the same straight line.

[0016] Further, the number of metal shorting posts of the metal shorting post array of the first radiating metal patch and the second radiating metal patch are different.

[0017] Further, the air dielectric constant of the air medium layer is 1, and the low dielectric constant can reduce the Q value of the antenna, thereby increasing the bandwidth of the antenna.

[0018] Further, by adjusting the size of the gap formed by the feeding patch and the first radiating metal patch and the second radiating metal patch, the capacitance of the gap formed by the feeding patch and the first radiating metal patch and the second radiating metal patch is changed, and by adjusting the position of the feeding metal column on the feeding patch, the reactance introduced at the feeding point is changed, thereby changing the impedance matching of the antenna, so as to improve the gain of the antenna and increase the total bandwidth of the antenna.

[0019] Further, the size of the metal ground plate is larger than the size of the radiating layer.

[0020] Further, by adjusting the shape and size difference of the two asymmetric first radiating metal patches and the second radiating metal patches, the resonant frequencies of the two patch antennas are different.

[0021] Further, the size of the first radiating metal patch is 0.8-0.9 times of the second radiating metal patch, forming two similar resonance points, so as to increase the impedance bandwidth of the antenna.

[0022] The present application adopts two asymmetric first radiating metal patches and second radiating metal patches, so that the resonance frequencies of the two patch antennas have a certain difference, and then connects the metal radiating antenna and the metal ground plate through a certain number of metal shorting columns, so as to enhance the radiation of the radiating antenna close to the middle feeding patch, and at the same time, the difference between the resonance frequencies of the two antennas is controlled by changing the position of the middle feeding patch, so as to realize the wide bandwidth of the antenna. The dielectric substrate of the present application is air, and the dielectric constant of air is 1. The low dielectric constant can reduce the Q value of the antenna, thereby increasing the bandwidth of the antenna, and at the same time, can replace the method of increasing the bandwidth by multi-layer patch and parasitic unit to a certain extent, so as to reduce the cross section of the antenna and reduce the weight of the antenna.

[0023] The present application has the following excellent effects:

[0024] (1) On the basis of maintaining the characteristics of small size of the original patch antenna single-layer patch and single-layer dielectric structure, the frequency band of the present application with the feeding point radiation coefficient S11 below-10dB is about 1.31-1.81GHz, the absolute bandwidth is 500MHz, and the relative bandwidth is as high as 32.1%, which is a breakthrough in wideband compared with the relative bandwidth of 3% of the traditional patch antenna.

[0025] (2) The dielectric layer adopts air, the Q value of the dielectric plate is reduced, and the coplanar capacitance is introduced by cutting a seam at the feeding point to improve the impedance matching and increase the bandwidth of the antenna, instead of the method of multi-layer patch and increasing parasitic unit, and the antenna of the present application has the characteristics of light weight, miniaturization, cost saving, easy integration and reducing the weight of the unmanned aerial vehicle. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0027] Figure 1 is a high-gain directional wideband antenna structure provided by the embodiment of the present application.

[0028] Figure 2 is a radiation layer and feeding patch structure of the antenna provided by the embodiment of the present application.

[0029] Figure 3 is an S11 parameter diagram of the antenna provided by the embodiment of the present application.

[0030] Figure 4 This is a 3D radiation pattern of the antenna provided in an embodiment of the present invention.

[0031] The markings in the diagram are: 1. Metal ground plane; 2. Radiation layer; 2-1. First radiating metal patch; 2-1-1. First notch; 2-1-2. First microstrip transmission line; 2-2. Second radiating metal patch; 2-2-1. Second notch; 2-2-2. Second microstrip transmission line; 3. Feed patch; 4. Feed metal post; 5. Metal short-circuit post. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0033] In the description of the embodiments of the present invention, it should be noted that the terms "center," "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore,

[0034] This should not be construed as a limitation on the embodiments of the present invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" or "linked" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0035] This embodiment provides a high-gain directional broadband antenna, such as Figures 1-2 It includes a metal ground plane 1, a radiating layer 2, a power supply patch, and an air dielectric layer located between the metal ground plane 1 and the radiating layer 2;

[0036] The size of the metal ground plate 1 is larger than that of the radiation layer 2 and is located below the radiation layer 2. The radiation layer 2 comprises first and second asymmetrically structured radiation metal patches 2-1 and 2-2. The first radiation metal patch 2-1 has a first notch 2-1-1 formed in a rectangular metal, and a first microstrip transmission line is arranged in the first notch 2-1-1. The first notch 2-1-1 is an integrally formed structure comprising a rectangular notch and an isosceles trapezoidal notch. The long side of the rectangular notch coincides with the upper base of the isosceles trapezoidal notch, and the lower base of the isosceles trapezoidal notch faces the second radiation metal patch 2-2. The first microstrip transmission line is a two-side stepped metal strip. Impedance matching is performed through the two-side stepped metal strip to increase the antenna bandwidth. The second radiation metal patch 2-2 has a second notch 2-2-1 formed in a rectangular metal, and a second microstrip transmission line is arranged in the second notch 2-2-1. The second notch 2-2-1 is an integrally formed structure comprising a rectangular notch and an isosceles trapezoidal notch. The long side of the rectangular notch coincides with the upper base of the isosceles trapezoidal notch, and the lower base of the isosceles trapezoidal notch faces the first radiation metal patch 2-1. The second microstrip transmission line is a metal strip.

[0037] The feeding patch adopts a coaxial line feeding section and is located between the first and second radiation metal patches 2-1 and 2-2. The centers of the first microstrip transmission line, the second microstrip transmission line and the feeding patch are located on the same straight line. There is a gap between each end of the feeding patch and the first and second radiation metal patches 2-1 and 2-2. A feeding metal column 4 is arranged on the feeding patch for connecting the feeding patch and the metal ground plate 1. The distance between the feeding metal column 4 and the center of the feeding patch is 5.1-5.2 mm. The asymmetric distribution of the feeding metal column 4 on the feeding patch can introduce different values of reactance, and together with the first and second radiation metal patches 2-1 and 2-2 with different sides, the impedance characteristics of the antenna are improved.

[0038] The first radiating metal patch 2-1, the second radiating metal patch 2-2 and the metal ground plate 1 are respectively provided with a group of metal shorting post 5 arrays. The metal shorting post 5 array is composed of a plurality of metal shorting posts 5 arranged at equal intervals, each metal shorting post 5 has a radius r of 0.3-0.5 mm and a height h of 19-21 mm, and the distance between each metal shorting post 5 is 0.5h. The distance between the metal shorting post 5 on the first radiating metal patch 2-1 and the outer edge of the first radiating metal patch 2-1 is 16-17 mm; the distance between the metal shorting post 5 on the second radiating metal patch 2-2 and the outer edge of the second radiating metal patch 2-2 is 20-21 mm. The number of metal shorting posts 5 in the metal shorting post 5 array provided on the first radiating metal patch 2-1 and the second radiating metal patch 2-2 is different; in this embodiment, the number of metal shorting posts 5 on the first radiating metal patch 2-1 and the second radiating metal patch 2-2 has a ratio of 11:9. By loading the metal shorting post 5, the effective current path can be increased, and the size of the antenna can be effectively reduced.

[0039] The air dielectric constant of the air medium layer is 1, and the low dielectric constant can reduce the Q value of the antenna, thereby increasing the bandwidth of the antenna.

[0040] By adjusting the size of the gap formed by the feeding patch and the first radiating metal patch 2-1 and the second radiating metal patch 2-2, the size of the capacitor formed by the feeding patch and the first radiating metal patch 2-1 and the second radiating metal patch 2-2 can be changed, and by adjusting the position of the feeding metal column 4 on the feeding patch, the reactance introduced at the feeding point can be changed, thereby changing the impedance matching of the antenna, thereby improving the gain of the antenna and increasing the total bandwidth of the antenna. The gap between the feeding patch and the first radiating metal patch 2-1 is a rectangular gap with a length S1 of 7.1-7.3 mm and a width W1 of 1.8-2 mm, and the gap between the feeding patch and the second radiating metal patch 2-2 is a rectangular gap with a length S2 of 7.1-7.3 mm and a width W2 of 2.5-2.6 mm. The gap can be equivalent to a capacitor, and by loading the gap, the effect of loading the capacitor can be achieved, the reactance introduced by the feeding patch can be compensated, the impedance matching of the antenna can be optimized, the impedance bandwidth of the antenna can be widened, and the antenna can work between 1.3 GHz and 1.8 GHz, with a relative bandwidth of up to 32.25%. Through this layout and shape, the effective electrical length of the current can be effectively increased, the impedance bandwidth of the antenna can be improved, and the size of the antenna can be reduced. At the same time, this layout can make the current distribution on the antenna concentrated on the upper patch, form a directional pattern, and have high gain at a specific frequency.

[0041] By adjusting the shape and size difference of the two asymmetric first radiating metal patches 2-1 and second radiating metal patches 2-2, the resonant frequencies of the two patch antennas can be different.

[0042] The first radiating metal patch 2-1 is slightly smaller than the second radiating metal patch 2-2, and the resonant frequency of the antenna is related to the effective current length of the antenna, so that different sizes of the radiating patch can have multiple resonant points, the size of the first radiating metal patch 2-1 is 0.8-0.9 times the size of the second radiating metal patch 2-2, forming two adjacent resonant points, so that the impedance bandwidth of the antenna is increased.

[0043] Table 1: The key size parameters of the antenna in the embodiment

[0044] Dimension parameter L1 L2 L3 L4 L5 L6 L7 Value range (mm) 15-16 14-15 24-25 12-13 17-18 14-15 14-15 Dimension parameter L8 r h D1 D2 D3 S1 Value range (mm) 19-21 0.3-0.5 19-21 16-17 20-21 5.1-5.2 7.1-7.3 Dimension parameter W1 S2 W3 - - - - Value range (mm) 1.8-2 7.1-7.3 2.5-2.6 - - - -

[0045] Figure 3 is the S11 parameter diagram of the antenna provided by the embodiment of the application, from which it can be seen that the operating frequency band of the antenna is between 1.3GHz-1.8GHz.

[0046] Figure 4 is the 3D directional diagram of the antenna provided by the embodiment of the application, from which it can be seen that the antenna is a directional antenna, and the maximum gain is 6.83dBi.

[0047] The above is the preferred embodiment of the application, it should be noted that for those skilled in the art, without departing from the principles of the application, can make a number of improvements and refinements, these improvements and refinements are also considered to be within the scope of the application.

Claims

1. A high-gain directional broadband antenna, characterized by The antenna comprises a metal ground plate (1), a radiation layer (2), a feed patch (3), and an air medium layer between the metal ground plate (1) and the radiation layer (2); The radiation layer (2) comprises a first radiation metal patch (2-1) and a second radiation metal patch (2-2) with asymmetric structures. The feed patch (3) is fed by a coaxial line section, which is located between the first radiation metal patch (2-1) and the second radiation metal patch (2-2). The feed patch (3) has gaps at both ends thereof from the first radiation metal patch (2-1) and the second radiation metal patch (2-2). A feed metal column (4) is arranged on the feed patch (3) for connecting the feed patch (3) and the metal ground plate (1). A group of metal shorting columns (5) are arranged between the first radiation metal patch (2-1), the second radiation metal patch (2-2) and the metal ground plate (1).

2. The high-gain directional broadband antenna according to claim 1, wherein, The first radiation metal patch (2-1) has a first notch (2-1-1) formed on a rectangular metal, and a first microstrip transmission line (2-1-2) arranged in the first notch (2-1-1). The second radiation metal patch (2-2) has a second notch (2-2-1) formed on a rectangular metal, and a second microstrip transmission line (2-2-2) arranged in the second notch (2-2-1).

3. The high-gain directional broadband antenna according to claim 2, wherein, The first notch (2-1-1) is an integrated structure comprising a rectangular notch and an isosceles trapezoidal notch. The long side of the rectangular notch coincides with the upper base of the isosceles trapezoidal notch, and the lower base of the isosceles trapezoidal notch faces the second radiation metal patch (2-2). The second notch (2-2-1) is an integrated structure comprising a rectangular notch and an isosceles trapezoidal notch. The long side of the rectangular notch coincides with the upper base of the isosceles trapezoidal notch, and the lower base of the isosceles trapezoidal notch faces the first radiation metal patch (2-1).

4. The high-gain directional broadband antenna according to claim 2, wherein, The first microstrip transmission line (2-1-2) is a ladder-shaped metal strip at both sides. The second microstrip transmission line (2-2-2) is a metal strip.

5. The high-gain directional broadband antenna according to claim 2, wherein, The centers of the first microstrip transmission line (2-1-2), the second microstrip transmission line (2-2-2) and the feed patch (3) are located on the same straight line.

6. The high-gain directional broadband antenna according to claim 1, wherein, The metal shorting column (5) array is composed of a plurality of metal shorting columns (5) arranged at equal intervals.

7. A high-gain directional wideband antenna according to claim 6, characterized in that, The number of metal shorting columns (5) in the metal shorting column (5) array arranged on the first radiation metal patch (2-1) and the second radiation metal patch (2-2) is different.

8. The high-gain directional broadband antenna according to claim 1, wherein, By adjusting the size of the gap formed by the feed patch (3) and the first radiation metal patch (2-1) and the second radiation metal patch (2-2), the size of the capacitance formed by the feed patch (3) and the first radiation metal patch (2-1) and the second radiation metal patch (2-2) can be changed, and by adjusting the position of the feed metal column (4) on the feed patch (3), the reactance introduced at the feed can be changed, thereby changing the impedance matching of the antenna, improving the gain of the antenna, and increasing the total bandwidth of the antenna.

9. The high-gain directional broadband antenna according to claim 1, wherein, By adjusting the shape and size difference of the two asymmetric first radiating metal patch (2-1), second radiating metal patch (2-2), the resonant frequency of the two patch antennas is different.

10. The high-gain directional broadband antenna according to claim 1, wherein, The size of the first radiating metal patch (2-1) is 0.8-0.9 times that of the second radiating metal patch (2-2), forming two similar resonant points, so as to increase the impedance bandwidth of the antenna.

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