CN113451753A

CN113451753A - Dipole antenna

Info

Publication number: CN113451753A
Application number: CN202010222661.4A
Authority: CN
Inventors: 刘若鹏; 赵治亚; 张从会
Original assignee: Kuang Chi Cutting Edge Technology Ltd
Current assignee: Kuang Chi Cutting Edge Technology Ltd
Priority date: 2020-03-26
Filing date: 2020-03-26
Publication date: 2021-09-28

Abstract

The invention relates to the technical field of antennas, and discloses a dipole antenna, which comprises: a conductive floor; the electromagnetic band gap structure layer is arranged on the conductive floor and is provided with ferrite and used for reducing the section of the dipole antenna; and at least one antenna unit arranged on the electromagnetic band gap structure layer. Each of the antenna units includes: the dipole plate comprises a first dipole plate and a second dipole plate which are arranged in the horizontal direction; and the short circuit plate comprises a first short circuit plate and a second short circuit plate which are arranged in the vertical direction. The first short circuit board is connected between the first dipole board and the electromagnetic band gap structure layer, and the second short circuit board is connected between the second dipole board and the electromagnetic band gap structure layer. Therefore, the problems of narrow bandwidth and high section of the omnidirectional antenna can be solved; and meanwhile, high gain, low profile and stable directional diagram of the dipole antenna are realized.

Description

Dipole antenna

Technical Field

The invention relates to the technical field of antennas, in particular to a dipole antenna.

Background

In recent years, the ultra-wideband communication technology has attracted much attention, and has been increasingly showing its unique advantages due to its advantages of greatly increasing the communication rate, low power consumption, high security, and the like. Antennas with absolute bandwidths exceeding 0.5GHz (centre frequency greater than 2.5GHz) or with relative bandwidths greater than 20% (centre frequency less than 2.5GHz) are generally considered ultra wide band antennas.

The antenna in practical application is attached to a metal conductor or a carrier similar to the metal conductor, and has a very different radiation characteristic compared with the antenna in free space, and the section of the antenna is close to a quarter wavelength of an operating frequency. Considering a series of factors such as mechanical problems and aerodynamic characteristics in practical applications, the antenna has an excessively large profile, so that the antenna is not easily conformed to the carrier, and the resistance of the antenna during movement is increased. Low profile antennas are therefore of great interest to antenna researchers due to their low profile, low wind resistance, robust construction, light weight, and ease of conforming to a carrier.

In the design of low-profile antennas, microstrip antennas are preferred because of their low profile, low cost, and ease of manufacture. However, conventional microstrip antennas typically have a narrow impedance bandwidth (less than 5%) and sometimes do not meet the bandwidth requirements of some modern wireless systems. Researchers at home and abroad propose various bandwidth enhancement technologies, such as a U-slot patch antenna, coplanar coupling feed and the like, and although the bandwidth can be increased while ensuring a low profile by adopting the technologies, generally, the microstrip antennas have strong back radiation in the whole working frequency range, which affects the performance of the antennas. With the increasing research of domestic and foreign scholars on new materials, an artificial electromagnetic band gap structure, EBG, is applied to the structure of a low-profile antenna.

The Ultra high frequency/Very high frequency (UHF/VHF) wave band has excellent penetration capability to forest and camouflage, and can be used for detecting forest vegetation in the civil field. The anti-counterfeiting detection method can be used for anti-counterfeiting detection in the military field and has important application value. The traditional UHF/VHF wave band antenna cannot meet the installation requirement of an airplane or an unmanned aerial vehicle due to large volume. There is a need for a small size, low profile antenna to replace the original antenna, while the new antenna needs to maintain a wider operating band, higher gain and good radiation pattern.

The traditional ebg (electromagnetic Band gap) structure can improve the gain of the antenna, but the effect is not obvious due to the size of the unit structure in the UHF Band, and the use is greatly limited.

Disclosure of Invention

In order to solve the technical problems, the invention provides a dipole antenna which can solve the problems of narrow bandwidth and high section of an omnidirectional antenna and simultaneously realize high gain, low section and stable directional diagram of the dipole antenna.

The present invention provides a dipole antenna, comprising:

a conductive floor;

the electromagnetic band gap structure layer is arranged on the conductive floor and is provided with ferrite and used for reducing the section of the dipole antenna; and

at least one antenna unit disposed on the electromagnetic bandgap structure layer, each of the antenna units comprising:

the dipole plate comprises a first dipole plate and a second dipole plate which are arranged in the horizontal direction;

the short circuit board comprises a first short circuit board and a second short circuit board which are arranged in the vertical direction;

the first short circuit board is connected between the first dipole board and the electromagnetic band gap structure layer, and the second short circuit board is connected between the second dipole board and the electromagnetic band gap structure layer.

Preferably, each of the antenna units further includes:

a feed cable, an outer conductor of which is connected to the first dipole plate;

and one end of the conductive strip is connected with the second dipole plate, and the other end of the conductive strip is connected with the inner conductor of the feed cable.

Preferably, the first dipole plate has a through hole;

the inner conductor of the feed cable is connected to the other end of the conductive strip through the through hole of the first dipole plate.

Preferably, the outer conductor of the feeder cable is further connected to a side surface of the first short circuit plate.

Preferably, the dipole antenna further comprises:

at least one antenna frame arranged corresponding to the at least one antenna unit;

wherein each of the antenna frames is disposed around the first dipole plate, the second dipole plate, the first short circuit plate, and the second short circuit plate of the corresponding antenna unit, and is connected to the conductive floor.

Preferably, the electromagnetic bandgap structure layer includes:

the metal layer is positioned on the conductive floor and is provided with a plurality of through holes;

the metal patches are periodically arranged on the metal layer;

the short circuit posts are respectively positioned in the through holes and respectively correspond to the metal patches; one end of each short-circuit column is connected with a corresponding metal patch, and the other end of each short-circuit column is connected with the conductive floor;

wherein the metal layer is made of the ferrite.

Preferably, a vertical distance from the surface of the dipole plate far away from the conductive floor to the surface of the conductive floor close to the dipole plate is equal to the height of the antenna frame.

Preferably, the first short circuit plate and the second short circuit plate are both rectangular or trapezoidal in shape.

Preferably, the first dipole plate and the second dipole plate are both rectangular, circular, trapezoidal or triangular in shape.

Preferably, the conductive floor is a metal floor, the first dipole plate, the second dipole plate, the first short-circuit plate and the second short-circuit plate are all metal structures, and the conductive strip is a metal strip.

Preferably, the cross-sectional height of the dipole antenna is 0.07 lambda; and λ is the wavelength corresponding to the central frequency of the working frequency band of the dipole antenna.

The invention has the beneficial effects that:

the invention provides a dipole antenna, which is characterized in that electromagnetic radiation of a dipole plate in the horizontal direction and a short-circuit plate in the vertical direction achieves equal-amplitude and same-phase excitation by a reasonable size design according to the principle that the dipole plate in the horizontal direction and the short-circuit plate in the vertical direction are complementary on the E surface and the H surface in an antenna directional diagram, so that the directional diagrams of the antenna on two polarization azimuth surfaces are kept consistent;

according to the ferrite-based hybrid EBG structure designed by the invention, the transmission of surface waves of the antenna is inhibited through the high-resistance state of the structure near the resonant frequency, and the gain and the radiation efficiency of the antenna are improved; the back lobe radiation is reduced through the homodromous reflection of the structure near the resonant frequency, the radiation intensity of the main direction is enhanced, and the directional diagram characteristic is improved; meanwhile, the reflector is used as a reflecting surface of the antenna, so that the low profile of the antenna is realized; the working frequency band can be widened by increasing the thickness of the metal patch;

the combined antenna formed by the dipole plate (electric dipole antenna) in the horizontal direction and the short-circuit plate (magnetic dipole antenna) in the vertical direction improves the directional diagram characteristic of the antenna, and meanwhile, the ferrite-based hybrid EBG structure is used for effectively reducing the section of the antenna, so that the combined antenna is highly innovative and widens the application range of the EBG structure on UHF/VHF band antennas.

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.

Fig. 1 is a perspective view of a dipole antenna according to an embodiment of the present invention;

fig. 2 is a perspective view of a dipole antenna having an antenna frame according to an embodiment of the present invention;

FIG. 3 shows a front view block diagram of the dipole antenna of FIG. 1;

fig. 4 is a front view structural view showing the dipole antenna having the antenna frame of fig. 2;

FIG. 5 shows a top view block diagram of the dipole antenna of FIG. 1;

fig. 6 shows a top structural view of the dipole antenna having the antenna frame of fig. 2;

fig. 7 is a cross-sectional view illustrating a feeding connection structure of a dipole antenna provided by an embodiment of the present invention;

FIG. 8 shows a schematic diagram of the electromagnetic bandgap structure of FIGS. 1 and 2;

FIG. 9 shows a schematic cross-sectional view of a cell structure of the electromagnetic bandgap structure of FIG. 8;

fig. 10 shows the radiation patterns of the dipole antenna of fig. 1 and 2;

FIG. 11 shows standing wave ratio plots for the dipole antenna of FIGS. 1 and 2;

fig. 12 shows a graph of the gain of the dipole antenna of fig. 1 and 2;

fig. 13 shows a gain curve of the dipole antenna of fig. 1 and 2 at Phi of 90 ° and at a frequency of 0.16 GHz;

fig. 14 shows a gain curve diagram of the dipole antenna of fig. 1 and 2 at 0 Phi and a frequency of 0.16 GHz;

fig. 15 shows a gain profile of the dipole antenna of fig. 1 and 2 at Phi 90 ° and a frequency of 0.27 GHz;

fig. 16 shows a gain curve diagram of the dipole antenna of fig. 1 and 2 at 0 °, Phi, and a frequency of 0.27 GHz;

fig. 17 shows a gain profile of the dipole antenna of fig. 1 and 2 at Phi 90 ° and a frequency of 0.38 GHz;

fig. 18 shows a gain curve for the dipole antenna of fig. 1 and 2 at 0 Phi and a frequency of 0.38 GHz.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

An EBG (Electromagnetic Band Gap) structure is an artificial periodic structure having a surface wave Band Gap characteristic and a homodromous reflection Band Gap characteristic, and has various types, generally composed of a mixture of a metal and a medium. The homotropic bandgap properties of EBG structures can be used to design low profile antennas. The conventional method using a conductive floor as a reflector of an antenna requires the antenna to be spaced apart from the conductive floor by a distance of about 1/4 ° of the wavelength of the operating frequency of the antenna because the phase of the reflected electromagnetic wave is 180 ° different from the phase of the original incident electromagnetic wave after the electromagnetic wave is incident on the conductive floor. When the antenna is away from the floor 1/4 wavelength, the phase after the reflection of the floor is the same as the original phase, and the radiation efficiency of the antenna is the highest. While the surface of the EBG structure (electromagnetic bandgap structure) enables the phase of the reflected electromagnetic wave to vary from 180 ° to-180 ° with increasing frequency, the reflected phase and the incident phase being in phase within a certain frequency band. According to the principle of the EBG structure, the low-profile antenna can be designed, and the height of the antenna is reduced.

The present invention will be described in detail below with reference to the accompanying drawings.

Fig. 1 is a perspective view of a dipole antenna according to an embodiment of the present invention. Fig. 2 is a perspective view of a dipole antenna having an antenna frame according to an embodiment of the present invention. Fig. 3 is a front view structural diagram showing the dipole antenna of fig. 1. Fig. 4 is a front view structural view showing the dipole antenna having the antenna frame of fig. 2. Fig. 5 shows a top view structural diagram of the dipole antenna of fig. 1. Fig. 6 is a top structural view of the dipole antenna having the antenna frame of fig. 2. Fig. 7 is a cross-sectional view illustrating a feeding connection structure of a dipole antenna according to an embodiment of the present invention.

As shown in fig. 1 to 7, an embodiment of the present invention provides a dipole antenna 100, which includes: a conductive floor 50, an electromagnetic bandgap structure layer 40 and at least one antenna element. In the present embodiment, the conductive floor 50 is a metal floor.

And the electromagnetic band gap structure layer 40 is arranged on the conductive floor 50. The electromagnetic band gap structure layer 40 has ferrite and serves to lower the profile of the dipole antenna 100. Specifically, the dipole plate 10 and the conductive floor 50 are disposed opposite to and parallel to each other.

Each of the antenna units includes: a dipole plate 10 and a shorting plate 20. The dipole plate 10 includes a first dipole plate 101 and a second dipole plate 102 disposed in a horizontal direction. The short circuit plate 20 includes a first short circuit plate 201 and a second short circuit plate 202 disposed in a vertical direction. Wherein, the first short circuit board 201 is connected between the first dipole board 101 and the electromagnetic bandgap structure layer 40, and the second short circuit board 202 is connected between the second dipole board 102 and the electromagnetic bandgap structure layer 40.

In the present embodiment, the dipole plate 10 and the short-circuiting plate 20 are all metal structures.

In the embodiment of the present invention, the first dipole plate 101 and the second dipole plate 102 are symmetrically disposed, the first short circuit plate 201 and the second short circuit plate 202 are symmetrically disposed, and the symmetry axis of the dipole plate 10 coincides with the symmetry axis of the short circuit plate 20.

Each of the antenna units further includes: a conductive strip 30 and a feeder cable 80. The outer conductor of the feeder cable 80 is connected to a first dipole plate 101. One end of the conductive strip 30 is connected to the second dipole plate 102 and the other end of the conductive strip 30 is connected to the inner conductor of the feeder cable 80.

In the present embodiment, the conductive strip 30 is an all-metal structure.

Specifically, the first dipole plate 101 has a through hole; the inner conductor of the feeder cable 80 is connected to the other end of the conductive strip 30 through the through hole of the first dipole plate 101. That is, the inner conductor of the feeder cable 80 is connected to the other end of the conductive strip 30 after passing through the through hole of the first dipole plate 101.

Further, the outer conductor of the feeder cable 80 is also connected to the side of the first short circuit plate 201.

In the embodiment of the present embodiment, the feeding cable 80 is vertically extended and connected between the first dipole plate 101 and the conductive ground plate 50, and the outer conductor 810 of the feeding cable 80 is connected to the side of the first short circuit plate 201. One end of the conductive strip 30 is connected to the second dipole plate 102, and the inner conductor 820 of the feeder cable 80 is connected to the other end of the conductive strip 30 after passing through the through hole of the first dipole plate 101. The radio frequency connector 60 is located on the surface of the conductive floor 50 far away from the electromagnetic bandgap structure layer 40, and the radio frequency connector 60 is connected with the feeder cable 80.

Taking the above-described embodiment as an example, as shown in fig. 1, 3 and 7, the structure formed by the first dipole plate 101 and the first short-circuit plate 201, and the second dipole plate 102 and the second short-circuit plate 202 is two mushroom-shaped T shapes that are substantially symmetrical when viewed from the front, and the feeding cable 80 and the second dipole plate 102 are connected between the tops of the T shapes by the conductive strips 30 to form a closed loop.

Further, the first and second

short circuit plates

201 and 201 are both rectangular or trapezoidal in shape, and the first and

second dipole plates

101 and 102 are both rectangular, circular, trapezoidal or triangular in shape. In the embodiment of the present invention, the first short-circuit plate 201 and the second short-circuit plate 202 are both rectangular and vertically connected to the upper surface of the electromagnetic bandgap structure layer 40, the first dipole plate 101 and the second dipole plate 102 are both rectangular, and a conductive strip 30 is connected between the first dipole plate 101 and the second dipole plate 102, and one end of the conductive strip 30 is formed with a feeding point extending downward along one side surface of the first short-circuit plate 201, which forms the structure shown in fig. 3.

The dipole antenna provided by the invention has the advantages that the dipole plate is symmetrically arranged in the horizontal direction and serves as the dipole antenna, the width of the dipole plate is regulated and controlled to achieve the broadband effect, the short circuit plate is symmetrically arranged in the vertical direction and serves as the magnetic dipole antenna, the dipole plate, the short circuit plate and the conductive floor form a closed loop, the broadband effect can be achieved by regulating and controlling the width of the short circuit plate, in the embodiment, the dipole plate and the short circuit plate can tend to be excited in the same amplitude and phase, and the consistency of directional diagrams of the antenna in E and H polarization planes can be realized by the complementary principle of the electromagnetic dipole antenna.

Further, the dipole antenna 100 further includes at least one antenna frame 70, and the at least one antenna frame 70 is disposed corresponding to the at least one antenna unit. Wherein each of the antenna frames 70 is disposed around the first dipole plate 101, the second dipole plate 102, the first short circuit plate 201 and the second short circuit plate 202 of the corresponding antenna unit, and is connected to the conductive floor 50.

Further, in the present embodiment, the vertical distance from the surface of the dipole plate 10 away from the conductive floor 50 to the surface of the conductive floor 50 close to the dipole plate 10 is equal to the height of the antenna frame 70, that is, the height of the antenna frame 70 is the same as the sectional height of the dipole antenna 100, as shown in fig. 4. In this embodiment, the antenna frame 70 mainly provides support for the dipole antenna 100 and its attachment to the platform.

Further, the electromagnetic bandgap structure layer 40 is an axisymmetric structure, and a symmetry axis thereof coincides with a symmetry axis of the first dipole plate 101 and the second dipole plate 102 in the dipole plate 10.

Fig. 8 and fig. 9 respectively show a schematic diagram of an electromagnetic bandgap structure layer in a dipole antenna provided by an embodiment of the present invention and a cross-sectional schematic diagram of a unit structure of the electromagnetic bandgap structure layer.

As shown in fig. 8 and 9, the electromagnetic bandgap structure layer 40 includes: a metal layer 420, a plurality of metal patches 410, and a plurality of shorting pillars 430. A metal layer 420 located on the conductive floor 50, wherein the metal layer 420 has a plurality of through holes 421. A plurality of metal patches 410 are periodically arranged on the metal layer 420; the plurality of shorting bars 430 are respectively located in the plurality of through holes 421 and respectively correspond to the plurality of metal patches 410. One end of each short post 430 is connected with the corresponding metal patch 410, and the other end of each short post 430 is connected with the conductive floor 50; the metal layer 420 is made of ferrite. Specifically, a plurality of metal patches 410 are arranged on the metal layer 420 in a two-dimensional grid. There is a certain distance between two adjacent metal patches 410. Further, there is a distance between the metal patch 410 and the upper surface of the metal layer 420 in the vertical direction.

Further, in this embodiment, the material of the metal layer 420 is preferably ferrite, and the ferrite is a metal oxide having ferrimagnetism. In terms of electrical properties, ferrites have a much higher resistivity than elemental metal or alloy magnetic materials, and also have higher dielectric properties. The magnetic properties of ferrites are also characterized by a high permeability at high frequencies. It should be noted that, under the same structure and the same dielectric constant, the frequency selectivity of the ferrite-based Electromagnetic Band Gap (EBG) structure is more obvious, the stop band is wider, and the peak value is higher than that of the isotropic EBG structure.

The ferrite-based EBG structure inhibits the propagation of the surface wave of the antenna (excited by various discontinuities in the transmission process) through the high-resistance state existing near the resonant frequency, and improves the gain and the radiation efficiency of the antenna; the back lobe radiation is reduced through the homodromous reflection of the structure near the resonant frequency, the radiation intensity of the main direction is enhanced, and the directional diagram characteristic is improved; meanwhile, the metal patch is used as a reflecting surface of the antenna, electromagnetic waves can only radiate to a half space due to being blocked on the surface of the EBG, so that the low profile of the antenna is realized, and the working frequency band can be widened by increasing the thickness of the metal patch.

Further, the shape of the metal patch 410 is any one of a rectangle, a triangle, or a hexagon. Further, the two-dimensional grid arrangement of the metal patches 410 is any one of a rectangular, triangular or hexagonal arrangement. It should be noted that, the two-dimensional grid arrangement of the metal patches 410 is related to the shape thereof, for example, but not limited to, when the shape of the metal patches 410 is rectangular, the two-dimensional grid arrangement of the metal patches 410 is rectangular, as shown in fig. 8.

Further, the metal layer 420 is formed with a plurality of via holes 421, and the via holes 421 penetrate the first surface and the second surface of the metal layer 420. Further, the cross-sectional shape of the through holes 421 is the same as that of the metal patches 410, and each through hole 421 corresponds to one metal patch 410, as shown in fig. 9.

Further, the antenna frame 70 is conformal with the projection shape of the electromagnetic bandgap structure layer 40 on the first surface of the conductive floor 50, and the respective centers of symmetry of the two coincide in the projection, as shown in fig. 6, in the present embodiment, the projection of the electromagnetic bandgap structure layer 40 on the first surface of the conductive floor 50 is a square, and the center of the projection coincides with the centers of the symmetry axes of the first short circuit board 201 and the second short circuit board 202. Specifically, the side length of the electromagnetic bandgap structure layer 40 is 0.38 λ, where λ is a wavelength corresponding to a central frequency of an operating frequency band of the dipole antenna in the embodiment of the present invention, as shown in fig. 5.

The present invention proposes a ferrite-based EBG structure, which is disposed at the bottom of an antenna, so that the antenna is not limited by 1/4 wavelength distance, and the cross section of the antenna is reduced, in this embodiment, the height of the cross section of the dipole antenna 100 is 0.07 λ, where λ is the wavelength corresponding to the center frequency of the working frequency band of the dipole antenna in the embodiment of the present invention, as shown in fig. 4.

Fig. 10 shows the radiation patterns of the dipole antenna in fig. 1 and fig. 2, as shown in fig. 10, the dipole plate in the horizontal direction and the short-circuit plate in the vertical direction can achieve equal-amplitude in-phase excitation under an ideal condition, so that the radiation patterns of the antenna when the patterns are complementary on the E plane and the H plane can be kept consistent in the present embodiment by reasonable size design (such as the width of the dipole plate and the width of the short-circuit plate in the vertical direction).

Fig. 11 shows a graph of the voltage standing wave ratio of the dipole antenna in fig. 1 and fig. 2, as shown in fig. 11, the center frequency of the antenna is 0.3GHz, the voltage standing wave ratio of the antenna is not greater than 3 in the frequency range of 0.16 to 0.38GHz, the relative bandwidth is 30%, and the impedance matching is good.

FIG. 12 shows a gain curve diagram of the dipole antenna in FIGS. 1 and 2, and it can be seen from FIG. 12 that the gain values of the antenna are all greater than 5dB in the frequency range of 0.15-0.4 GHz, and are higher when the gain value is around 0.38GHz and greater than 7dB at the highest.

Fig. 13 and 14 show gain graphs of the dipole antenna in fig. 1 and 2 at Phi 90 ° and Phi 0 ° and at 0.16GHz, respectively, in fig. 13, the dipole antenna has a maximum main lobe radiation power of 5.27dB in the direction of Phi 90 °, i.e., in the XOZ plane, at 0.16GHz, a maximum main lobe radiation power of Theta 0 °, a main lobe width of 101.3 °, and a side lobe level of-13.6 dB in fig. 13, and in fig. 14, the dipole antenna has a maximum main lobe radiation power of 5.27dB in the direction of Phi 0 °, i.e., in the YOZ plane, a maximum main lobe radiation power of-2 °, a main lobe width of 91.2 °, and a side lobe level of-13.4 dB in the direction of Phi 0.16 GHz.

Fig. 15 and 16 show gain graphs of the dipole antenna in fig. 1 and 2 at Phi 90 ° and Phi 0 ° and at 0.27GHz, respectively, in fig. 15, the dipole antenna has a maximum main lobe radiation power of 5.02dB in the direction of Phi 90 °, Theta 0 °, and a main lobe width of 79.5 ° without side lobe formation in the XOZ plane at 0.27GHz, and in fig. 16, the dipole antenna has a maximum main lobe radiation power of 5.02dB in the direction of Phi 0 °, YOZ plane, and Theta-1 °, a main lobe width of 114 °, and a side lobe level of-12.9 dB in the direction of Phi 0 °, and a side lobe level of-1 ° in the YOZ plane at 0.27 GHz.

Fig. 17 and 18 show gain graphs of the dipole antenna in fig. 1 and 2 at Phi 90 ° and Phi 0 ° and at 0.38GHz, respectively, in fig. 17, the dipole antenna has a main lobe radiation power of 7.02dB at a maximum in the direction Phi 90 °, i.e., in the XOZ plane, at 0.38GHz, and has a main lobe radiation power of 0.06 dB at a maximum in the direction Phi 0 °, i.e., in the YOZ plane, and has a main lobe width of 63.8 ° and a side lobe level of-12.6 dB, and in fig. 18, the dipole antenna has a main lobe radiation power of 3 °, a main lobe width of 60.5 ° and a side lobe level of-12.6 dB at 0.38 GHz.

In summary, the frequency bandwidth of the dipole antenna provided by the embodiment of the present invention can reach 80%, the gain of the antenna in the whole bandwidth is above 5dB, and the directional diagram is stable. The combined antenna formed by the dipole plate (electric dipole antenna) in the horizontal direction and the short-circuit plate (magnetic dipole antenna) in the vertical direction improves the directional diagram characteristic of the antenna, and meanwhile, the ferrite-based EBG structure is used for effectively reducing the section of the antenna, so that the combined antenna is strong in innovation and widens the application range of the EBG structure on UHF/VHF band antennas.

It should be noted that in the description of the present invention, it is to be understood that the terms "upper", "lower", "inner", and the like, indicate orientation or positional relationship, are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the referenced components or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention.

Further, in this document, the contained terms "include", "contain" or any other variation thereof are intended to cover a non-exclusive inclusion, so that a process, a method, an article or an apparatus including a series of elements includes not only those elements but also other elements not explicitly listed or inherent to such process, method, article or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Finally, it should be noted that: it should be understood that the above examples are only for clearly illustrating the present invention and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the scope of the invention.

Claims

1. A dipole antenna, comprising:

a conductive floor;

2. A dipole antenna according to claim 1 and wherein each of said antenna elements further comprises:

3. A dipole antenna according to claim 2, wherein: the first dipole plate is provided with a through hole;

4. A dipole antenna according to claim 2, wherein: the outer conductor of the feed cable is also connected to the side of the first short circuit plate.

5. A dipole antenna as recited in claim 1, further comprising:

6. A dipole antenna according to claim 1 and wherein said electromagnetic bandgap structure layer comprises:

the metal patches are periodically arranged on the metal layer;

wherein the metal layer is made of the ferrite.

7. The dipole antenna of claim 5, wherein: the vertical distance from the surface of the dipole plate far away from the conductive floor to the surface of the conductive floor close to the dipole plate is equal to the height of the antenna frame.

8. A dipole antenna according to claim 1, wherein: the first short circuit plate and the second short circuit plate are both rectangular or trapezoidal in shape; the first dipole plate and the second dipole plate are all rectangular, circular, trapezoidal or triangular in shape.

9. A dipole antenna according to claim 2, wherein: the conductive floor is a metal floor, the first dipole plate, the second dipole plate, the first short-circuit plate and the second short-circuit plate are all metal structures, and the conductive strips are metal strips.

10. A dipole antenna according to claim 1, wherein: the cross-sectional height of the dipole antenna is 0.07 lambda; and λ is the wavelength corresponding to the central frequency of the working frequency band of the dipole antenna.