CN212033242U

CN212033242U - Microstrip antenna

Info

Publication number: CN212033242U
Application number: CN202020639545.8U
Authority: CN
Inventors: 杨晓东; 梁榜; 付荣
Original assignee: Lanto Electronic Ltd
Current assignee: Lanto Electronic Ltd; Kunshan Liantao Electronics Co Ltd
Priority date: 2020-04-24
Filing date: 2020-04-24
Publication date: 2020-11-27
Anticipated expiration: 2030-04-24
Also published as: TWM605393U

Abstract

The feed probe of the microstrip antenna sequentially penetrates through the ground plate, the second dielectric substrate, the second radiation patch and the first dielectric substrate from bottom to top and then is connected with the first radiation patch for feeding, and the first radiation patch directly feeds power through the feed probe and is mutually electromagnetically coupled with the second radiation patch so as to realize double-frequency work. The microstrip antenna disclosed by the invention has a simple structure, and realizes the characteristic of single-feed double-frequency working of the microstrip antenna by arranging the double-layer radiation patches.

Description

Microstrip antenna

Technical Field

The utility model relates to an antenna technology field, concretely relates to microstrip antenna.

Background

With the development of communication technology, microstrip antennas have been widely used due to their small size, light weight, low profile and easy integration. For example, microstrip antennas may be used for mobile communications, position location navigation, radio frequency identification, and the like. Different application industries have different application frequency bands, and a common microstrip antenna single feed has a single-frequency characteristic and cannot work at different application frequency bands simultaneously.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model provides a microstrip antenna has realized that microstrip antenna singly presents the characteristic of dual-frenquency work.

The embodiment of the utility model provides a microstrip antenna, microstrip antenna includes:

the first radiation patch, the first dielectric substrate, the second radiation patch, the second dielectric substrate and the grounding plate are sequentially arranged from top to bottom;

the feeding probe sequentially penetrates through the grounding plate, the second medium substrate, the second radiation patch and the first medium substrate from bottom to top and is connected with the first radiation patch for feeding;

wherein the second radiating patch and the ground plate respectively have a first annular hole and a second annular hole, the feeding probe passes through the first annular hole and the second annular hole to feed the first radiating patch, and the first radiating patch is configured to be mutually and electromagnetically coupled with the second radiating patch under the feeding excitation of the feeding probe.

Further, the first radiation patch has two first cut angles, and the two first cut angles are respectively arranged at the diagonal positions of the first radiation patch;

the second radiation patch is provided with two second cutting angles which are respectively arranged at the diagonal positions of the second radiation patch.

Further, the positions of the two first chamfer angles and the positions of the two second chamfer angles are arranged in a staggered mode.

Further, the shape of the first corner cut and the shape of the second corner cut are rectangular, square or triangular.

Further, the area of the first radiating patch is smaller than the area of the second radiating patch.

Further, the shape of the first radiation patch and the shape of the second radiation patch are rectangular or square.

Further, the frequency of the first radiation patch is 8GHz, and the frequency of the second radiation patch is 6.5 GHz.

Further, the microstrip antenna also comprises a bonding pad which is positioned in the first annular hole, and the feed probe penetrates through the bonding pad.

The feed probe of the microstrip antenna of the embodiment sequentially penetrates through the ground plate, the second dielectric substrate, the second radiation patch and the first dielectric substrate from bottom to top and then is connected with the first radiation patch for feeding, and the first radiation patch is excited by feeding of the feed probe and is mutually electromagnetically coupled with the second radiation patch so as to realize double-frequency work. The microstrip antenna of this embodiment is simple in structure, and the characteristic of single-feed dual-frequency operation of the microstrip antenna is realized by arranging the double-layer radiation patch.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

fig. 1 is a cross-sectional view of a microstrip antenna according to an embodiment of the present invention;

fig. 2 is a top view of a first and second radiating patch of an embodiment of the present invention;

fig. 3 is a top view of a second radiation patch of an embodiment of the present invention;

fig. 4 is a top view of a ground plate in an embodiment of the invention;

fig. 5 is a simulation result diagram before the corner cut of the microstrip antenna according to the embodiment of the present invention;

fig. 6 is a diagram of simulation results after the microstrip antenna of the embodiment of the present invention is chamfered;

fig. 7 is a simulation result diagram of the axial ratio of the microstrip antenna before the corner cut according to the embodiment of the present invention varying with the frequency;

fig. 8 is a simulation result diagram of the axial ratio of the microstrip antenna after the corner cut according to the embodiment of the present invention.

Detailed Description

The present invention will be described below based on examples, but the present invention is not limited to only these examples. In the following detailed description of the present invention, certain specific details are set forth in detail. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. Well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the present invention.

Further, those of ordinary skill in the art will appreciate that the drawings provided herein are for illustrative purposes and are not necessarily drawn to scale.

Unless the context clearly requires otherwise, throughout the description, the words "comprise", "comprising", and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is, what is meant is "including, but not limited to".

In the description of the present invention, it is to be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In addition, in the description of the present invention, "a plurality" means two or more unless otherwise specified.

Unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are intended to be inclusive and mean that, for example, they may be fixedly connected or detachably connected or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

Fig. 1-4 are schematic structural diagrams of the microstrip antenna of the present embodiment. As shown in fig. 1, the microstrip antenna includes a first radiation patch 1, a first dielectric substrate 2, a second radiation patch 3, a second dielectric substrate 4, a ground plate 5, and a feed probe 6. The first radiation patch 1, the first dielectric substrate 2, the second radiation patch 3, the second dielectric substrate 4 and the grounding plate 5 are sequentially arranged from top to bottom. That is, the second dielectric substrate 4 is located above the ground plate 5, the second radiation patch 3 is located above the second dielectric substrate 4, the first dielectric substrate 2 is located above the second radiation patch 3, and the first radiation patch 1 is located above the first dielectric substrate 2. The second radiating patch 3 may act as both an antenna and a ground plane for the first radiating patch 1. The ground plane 5 serves as a ground plane for the second radiating patch 2.

The feed probe 6 sequentially penetrates through the grounding plate 5, the second dielectric substrate 4, the second radiation patch 3 and the first dielectric substrate 2 from bottom to top and then is directly fed to the first radiation patch 1, and then the first radiation patch 1 and the second radiation patch 3 are mutually electromagnetically coupled, so that the single-feed and double-frequency working characteristics of the microstrip antenna are realized.

Specifically, the second radiation patch 3 has a first annular hole 31, and the ground plate 5 has a second annular hole 51. The first annular hole 31 is located above the second annular hole 51, and the first annular hole 31 and the second annular hole 51 have respective hole diameters larger than the diameter of the feed probe 6. When the feeding probe 6 passes through the second radiation patch 3 and the ground plate 5, the feeding probe passes through the second annular hole 51 of the ground plate 5 and the first annular hole 31 of the second radiation patch 3, and does not contact the ground plate 5 and the second radiation patch 3, so that the second radiation patch 3 can be prevented from contacting the feeding probe 6 to cause short circuit. The first radiating patch 1 is directly fed through the feeding probe 6 to form a high-frequency antenna, and then the first radiating patch 1 and the second radiating patch 3 are mutually electromagnetically coupled to form a low-frequency antenna. That is, after the feeding probe 6 feeds, the second radiation patch 3 is responsible for receiving or transmitting the low-frequency signal (preset to 6.5GHz), and the first radiation patch 1 is responsible for receiving and transmitting the high-frequency signal (preset to 8 GHz).

The resonant frequency of the first radiating patch 1 and the second radiating patch 3 is basically determined by the side length of the patches, so that the microstrip antenna can select radiating patches with different lengths to realize the work at different frequencies.

In the present embodiment, the first annular hole 31 and the second annular hole 51 are circular holes and are coaxially disposed, that is, the feeding probe 6 is coaxially fed. Besides, the shapes of the first annular hole 31 and the second annular hole 51 may be circular, square, oval, triangular, and the like. The first annular hole 31 and the second annular hole 51 may not be completely coaxial, as long as the feeding probe 6 passes through the first annular hole 31 and the second annular hole 51 and does not contact the ground plate 5 and the second radiating patch 3.

In the present embodiment, the area of the first radiation patch 1 and the area of the second radiation patch 3 are both smaller than the areas of the first dielectric substrate 2, the second dielectric substrate 4, and the ground plate 5. The first radiation patch 1 and the second radiation patch 3 are located inside the first dielectric substrate 2, the second dielectric substrate 4 and the ground plate 5 in a plan view direction. The area of the first radiation patch 1 is smaller than the area of the second radiation patch 3. The first radiation patches 1 are all located inside the second radiation patches 3 in the top view direction.

In this embodiment, the first radiation patch 1, the second radiation patch 3, the first dielectric substrate 2, the second dielectric substrate 4, and the ground plate 5 are square. The centers of the first and

second radiating patches

1 and 3 coincide and have the same perpendicular bisector, as shown in fig. 2. The first annular hole 31 is disposed on the perpendicular bisector of the second radiating patch 3, the second annular hole 51 is disposed on the perpendicular bisector of the ground plate 5, and the first annular hole 31 and the second annular hole 51 are coaxially disposed, as shown in fig. 3 and 4. The coupling point of the first radiating patch 1 and the feed probe 6 is located on the perpendicular bisector of the first radiating patch 1 and close to the edge of the radiating patch. In other alternative implementations, the first annular hole 31, the second annular hole 51 and the feeding probe 6 may be disposed at other positions to meet the feeding requirement.

The first radiating patch 1 comprises two first cut angles 11 and the second radiating patch 3 has two second cut angles 32, as shown in fig. 2. The two first chamfers 11 are respectively arranged at the diagonal positions of the first radiation patch 1, the two second chamfers 32 are respectively arranged at the diagonal positions of the second radiation patch 3, and the positions of the two first chamfers 11 and the positions of the two second chamfers 32 are arranged in a staggered manner. After the first radiation patch 1 and the second radiation patch 3 are chamfered, a high-frequency resonance is added to the microstrip antenna on the basis of the original resonance, and the original resonance is very close to the high-frequency resonance. That is to say, a high-frequency path is added on the original resonant path, so that the bandwidth of the microstrip antenna is widened, and the problem of narrow band of the microstrip antenna is solved.

Fig. 5 is a diagram of simulation results of a microstrip antenna before corner cut of a radiating patch. As shown in fig. 5, before the corner cut of the radiating patch, the microstrip antenna will have two resonances at 6.5GHz and 8GHz, respectively, due to the coupling effect. Due to the narrow-band characteristic of the microstrip antenna, the actual bandwidth of the microstrip antenna is not wide, and the bandwidths less than-10 dB are about 80MHz and 75MHz, respectively, as shown in fig. 5. Fig. 6 is a diagram of simulation results of the microstrip antenna after the corner cut of the radiation patch. Compared with the graph of fig. 5, the microstrip antenna has one more resonance point at the original 6.5GHz and 8GHz resonance frequency points, generates a waveform similar to W, has bandwidths less than-10 dB reaching 190MHz and 188MHz, and has increased 110MHz and 103MHz compared with the original bandwidths (80MHz and 75 MHz).

That is to say, the method for expanding the bandwidth of the microstrip antenna is to open two rectangular corners with proper size at opposite angles of the radiation patch, and the two tangent angles are separated in a staggered manner, so that compared with the surface of the original radiation patch, a new current path is added, and the bandwidth of the microstrip antenna is effectively expanded.

In the present embodiment, the first corner cut 11 and the second corner cut 32 are rectangular. The dimensions of the first chamfer 11 and the second chamfer 32 are obtained by continuous optimization. If the size of the cut angle is too small, the original linear polarization antenna is easily changed into a circularly polarized antenna, if the size is too large, a current with a too short current path is added, a larger frequency is generated compared with the initial frequency, only if the size is proper, a frequency slightly larger than the original antenna is generated, and a waveform similar to W is generated in an S11 curve by overlapping the two antennas, so that the bandwidth of the antenna is effectively expanded. The first chamfer 11 and the second chamfer 32 are of different dimensions for different requirements. For example, the size of the chamfer is to look at the requirement of the microstrip antenna for S11 (return loss characteristic). S11 is one of the S parameters, representing the return loss characteristics, generally seen by the network analyzer for dB values of loss and impedance characteristics. S11 shows that the antenna has poor radiation efficiency, and the larger the value, the more energy reflected by the antenna itself, so the worse the efficiency of the microstrip antenna.

Fig. 7 is an axial ratio diagram corresponding to each frequency before the microstrip antenna is chamfered. Before the corner cut, the axial ratio of the microstrip antenna is more than 10dB, and the microstrip antenna belongs to a linearly polarized antenna. Fig. 8 is an axial ratio diagram corresponding to each frequency after the microstrip antenna is cut. After the corner cut, the axial ratio of other frequency points is about 4dB except the axial ratio at 6.56GHz and 8.12GHz, and the axial ratio of other frequency points is about 4dB, and the microstrip antenna still belongs to a linear polarization antenna after the corner cut according to the requirement that the axial ratio of circular polarization is less than 3 dB. Therefore, the microstrip antenna does not affect the polarization form of the antenna before and after the corner cut.

In this embodiment, the shape of the first chamfer 11 and the shape of the second chamfer 32 may also be square, triangular, or the like. The shape of the first radiation patch 1 and the shape of the second radiation patch 3 may also be set to be rectangular, circular, or the like.

The first radiation patch 1, the second radiation patch 3, and the ground plate 5 are formed by coating a conductive metal material. The conductive metal material can be Ag, Cu and other materials, is manufactured by a plane printing process or a photoetching corrosion process, and can also be realized by an LTCC (low temperature co-fired ceramic) process.

The first dielectric substrate 2 and the second dielectric substrate 4 are high-frequency plates with low dielectric constant and low loss. The efficiency of the microstrip antenna is closely related to the thickness, dielectric constant and the like of the dielectric substrate, so that the microstrip antenna can select the first dielectric substrate 2 and the second dielectric substrate 4 with preset thicknesses according to specific requirements. In this embodiment, the dielectric constant of the first dielectric substrate 2 and the second dielectric substrate 4 is 3.0, and the loss is 0.003. The first dielectric substrate 2 and the second dielectric substrate 4 can be ceramic dielectric substrates, organic dielectric substrates, or the like.

In this embodiment, the microstrip antenna further includes a pad 7 located in the first annular hole 31. The pad 7 is smaller than the first annular hole 31 such that an annular gap is formed between the pad 7 and the first annular hole 31. The feeding probe 6 passes through the bonding pad 7, and the feeding probe 6 can be reinforced by the bonding pad 7, so that the feeding probe 6 is prevented from shaking in the first annular hole 31 and the second annular hole 51 to contact with the second radiation patch 3 to cause short circuit.

The microstrip antenna of the embodiment realizes the characteristic of single-feed dual-frequency working of the microstrip antenna by exciting the first radiation patch in a direct coupling mode and exciting the second radiation patch in an indirect coupling mode through the radiation patch lamination and the feed probe, solves the problem that the single feed of the conventional microstrip antenna can only realize single frequency, expands the bandwidth of the microstrip antenna by carrying out proper corner cut on the radiation patch, and overcomes the defect of narrow band of the microstrip antenna.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. A microstrip antenna, comprising:

the antenna comprises a first radiation patch (1), a first dielectric substrate (2), a second radiation patch (3), a second dielectric substrate (4) and a grounding plate (5) which are arranged from top to bottom in sequence;

the feeding probe (6) sequentially penetrates through the grounding plate (5), the second dielectric substrate (4), the second radiation patch (3) and the first dielectric substrate (2) from bottom to top and is connected with the first radiation patch (1) for feeding;

wherein the second radiation patch (3) and the ground plate (5) are respectively provided with a first annular hole (31) and a second annular hole (51), the feed probe (6) passes through the first annular hole (31) and the second annular hole (51) to feed with the first radiation patch (1), and the first radiation patch (1) is configured to be mutually and electromagnetically coupled with the second radiation patch (3) under the feed excitation of the feed probe (6).

2. A microstrip antenna according to claim 1, wherein the first radiating patch (1) has two first cut corners (11), the two first cut corners (11) being respectively arranged at diagonal positions of the first radiating patch (1);

the second radiation patch (3) is provided with two second cutting angles (32), and the two second cutting angles (32) are respectively arranged at the diagonal positions of the second radiation patch (3).

3. Microstrip antenna according to claim 2, characterized in that the positions of the two first cut corners (11) and the positions of the two second cut corners (32) are staggered with respect to each other.

4. A microstrip antenna according to claim 2 or 3, wherein the shape of the first corner cut (11) and the shape of the second corner cut (32) are rectangular, square or triangular.

5. A microstrip antenna according to any of claims 1-3, characterized in that the area of the first radiating patch (1) is smaller than the area of the second radiating patch (3).

6. Microstrip antenna according to claim 5, characterized in that the shape of the first radiating patch (1) and the shape of the second radiating patch (3) are rectangular or square.

7. Microstrip antenna according to claim 1, characterized in that the frequency of the first radiating patch (1) is 8GHz and the frequency of the second radiating patch (3) is 6.5 GHz.

8. A microstrip antenna according to claim 1, further comprising a pad (7) located within the first annular aperture (31), the feed probe (6) passing through the pad (7).