CN113097724B

CN113097724B - Dielectric resonant antenna

Info

Publication number: CN113097724B
Application number: CN202110380934.2A
Authority: CN
Inventors: 陆阳; 翟迪; 高鸿坚
Original assignee: State Grid Corp of China SGCC; State Grid Zhejiang Electric Power Co Ltd; Global Energy Interconnection Research Institute
Current assignee: State Grid Corp of China SGCC; State Grid Zhejiang Electric Power Co Ltd; Global Energy Interconnection Research Institute
Priority date: 2021-04-09
Filing date: 2021-04-09
Publication date: 2022-10-11
Anticipated expiration: 2041-04-09
Also published as: CN113097724A

Abstract

The embodiment of the invention provides a dielectric resonant antenna, relates to the technical field of communication, and can be excited by utilizing surface waves with most energy attached to a single-conductor transmission line. The embodiment of the invention comprises the following steps: feed coaxial cables, power lines, dielectric resonators and tapered shafts. The input end of the feed coaxial cable is used for connecting an information source, the conical shaft can convert input electromagnetic waves in a transverse electromagnetic wave (TEM) mode into surface waves in a transverse electromagnetic wave (TM) mode, and the power line is connected to the fixed end of the dielectric resonator. The invention relates to a dielectric antenna excited by power line surface wave radiation, which has the characteristics of simple structure, high broadband gain and oblique incidence angle.

Description

Dielectric resonant antenna

Technical Field

The embodiment of the invention relates to the technical field of communication, in particular to a dielectric resonant antenna.

Background

Higher data rates and carrier frequencies will be the features of 5G networks, cells will inevitably become smaller, and millimeter wave signals have become a research hotspot for wireless communication.

Surface waves, the phenomenon in which electromagnetic energy is transmitted concentrated near the interface of two media. According to previous researches, electromagnetic waves of various modes can be excited on a single conductor bare wire (Sommerfeld wire) or a conductor wire (Goubau wire) coated with a dielectric layer. These two structures are called open waveguide and surface wave waveguide, and unlike the closed waveguide structure, electromagnetic waves can be radiated to infinity. Generally, a wave whose energy is concentrated near an open waveguide is called a surface wave, and a wave which can be radiated to infinity is called a "radiated wave".

At low frequency, the single-wire surface wave waveguide can be used as a long-distance transmission line. The united states has long used single-wire surface wave waveguides for long distance transmission to achieve television distribution. Is one aspect of microwave technology research, and is often used for feeder lines from a machine room to antennas. A new model of using traditional overhead power lines has also been proposed and applied as a third conduit and solution to the "last mile" problem.

Disclosure of Invention

An object of an embodiment of the present invention is to provide a dielectric resonator antenna that excites a dielectric resonator using TM mode surface wave radiation to achieve a good broadband end-fire characteristic. The specific technical scheme is as follows:

a dielectric resonant antenna, comprising: feed coaxial cable, power line, dielectric resonator and conical shaft, wherein:

the input end of the feed coaxial cable is used for connecting an information source;

the power line is respectively connected with the output end of the feed coaxial cable and the input end of the dielectric resonator; the power line includes a conductive line for transmitting an electromagnetic wave of a TM mode and a second insulating layer covering the conductive line.

The feeding coaxial cable comprises a first inner conductor and a first insulating layer wrapping the first inner conductor, wherein the first inner conductor is electrically connected with one end of the conducting wire.

The feed coaxial cable also comprises a shielding layer coating the first insulating layer;

the conical shaft is wound on the periphery of the power line and connected with the periphery of the shielding layer.

The second inner conductor of the dielectric resonator is electrically connected to the other end of the conductive line.

The dielectric resonator further includes a third insulating layer covering the second inner conductor.

The dielectric resonator comprises a body and is square; the body covers the half circumference of the third insulating layer.

The end part of the body is provided with an annular medium sleeve; the annular medium sleeve is suitable for sleeving and fixing the power line.

The material of the first insulating layer, the second insulating layer and the third insulating layer comprises polyethylene.

The material of the first inner conductor, the conductive line and the second inner conductor comprises copper.

The relative dielectric constant of the body is the same as that of the annular dielectric sleeve.

The technical characteristics of the embodiment of the invention can at least bring the following beneficial effects: in the embodiment of the invention, the electromagnetic wave is transmitted in the TM mode in the power line, and the surface wave has the characteristic of low loss and wide band, and the feeding structure is simple and the size is relatively small. And the shape of the dielectric resonance antenna has a plurality of shapes, and the design has great flexibility. The dielectric resonant antenna has the advantages of simple processing, lower cost and small loss.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic structural diagram of a dielectric resonator antenna according to an embodiment of the present invention;

fig. 2 is a longitudinal sectional view of a dielectric resonator antenna according to an embodiment of the present invention;

fig. 3 is a cross-sectional view of a dielectric resonator antenna according to an embodiment of the present invention;

FIG. 4 is a graph of S11 reflection coefficient (return loss) as a function of source signal frequency with resonator height as a parameter according to an embodiment of the present invention;

FIG. 5 is a two-dimensional radiation pattern at a frequency of 53GHz in a simulation of an embodiment of the invention;

FIG. 6 is a two-dimensional radiation pattern at a frequency of 67GHz in a simulation of an embodiment of the invention.

Description of reference numerals: 1. a feed coaxial cable; 11. a first inner conductor; 12. a first insulating layer; 13. a shielding layer; 2. a power line; 21. a conductive wire; 22. a second insulating layer; 3. a dielectric resonator; 31. an annular media sleeve; 32. a body; 33. a third insulating layer; 34. a second inner conductor; 4. a tapered shaft.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, 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 the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Furthermore, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

In order to reduce transmission loss of a feeder line and achieve a good broadband end-fire characteristic, an embodiment of the present invention provides a dielectric resonator antenna, as shown in fig. 1, the dielectric resonator antenna includes: a feed coaxial cable 1, a power line 2 and a dielectric resonator 3, a tapered shaft 4, wherein,

the input end of the feeding coaxial cable 1 is used for connecting an information source, and the feeding coaxial cable 1 is used for inputting Electromagnetic waves in a Transverse Electromagnetic wave (TEM) mode.

The power line 2 is respectively connected with the output end of the feeding coaxial cable 1 and the input end of the second inner conductor 34 of the dielectric resonator 3, the power line 2 comprises a conductive line 21 and a second insulating layer 22 coating the conductive line 21, and the conductive line 21 is used for transmitting the electromagnetic wave of the TM mode.

The conical shaft 4 is horn-shaped, the conical shaft 4 is wound on the power line 2, and the small-opening end is fixedly connected to the feed coaxial cable 1. The small-opening end of the tapered shaft 4 is connected to the first insulating layer 12 of the feeding coaxial cable 1, and is used for exciting electromagnetic waves in a TM mode to be transmitted along the cable.

In an embodiment of the invention, the structure of the tapered shaft 4 may be cast from a very thin brass material, with a length close to half a wavelength (if 60GHz at operating frequency, 5mm free space wavelength).

Electromagnetic waves can be transmitted in any one of the following three transmission modes: TEM mode, TM mode, and Transverse Electric wave (TE) mode.

Among them, the electromagnetic wave of the TEM mode has no electric field component and no magnetic field component in the propagation direction.

Electromagnetic waves in the TE mode have a magnetic field component in the direction of propagation, but no electric field component.

An electromagnetic wave in the TM mode has an electric field component but no magnetic field component in the direction of propagation.

The electric field lines of the electromagnetic waves of the TEM mode in the coaxial line emanate from the inner conductor, terminating to the outer conductor. The TEM mode is excited by the actual current, while the TM wave is excited by the displacement current. Nearby conductors may provide termination points in addition to the line itself, thereby reducing energy coupling into the TM wave. When the TEM wave passes through the tapered axis 4, the electric field lines bend, terminating elsewhere in the inner conductor. Each field line must have a termination point that can be up to half a wavelength. Therefore, to support propagation of the TM mode, the transmission line must be at least half a wavelength long.

In the embodiment of the present invention, the power line 2 includes two ends, one of which is connected to the output end of the feeding coaxial cable 1 and the other of which is connected to the dielectric resonator 3.

Illustratively, the characteristic impedance of the feeding coaxial cable 1 may be 50 ohms.

The technical characteristics of the embodiment of the invention can at least bring the following beneficial effects: in the embodiment of the invention, the electromagnetic wave is transmitted in the TM mode in the power line 2, and the surface wave has the characteristic of low loss and wide band, and the power feeding structure is simple and has relatively small size. And the shape of the dielectric resonance antenna has a plurality of shapes, and the design has great flexibility. The dielectric resonant antenna has the advantages of simple processing, low cost and low loss.

In the embodiment of the present invention, the feeding coaxial cable 1 includes a first inner conductor 11 and a first insulating layer 12 covering the first inner conductor 11, wherein: the first inner conductor 11 is electrically connected to one end of the conductive wire 21. Optionally, the radius of the first inner conductor 11 of the feeding coaxial cable 1 is 0.5 millimeter (mm).

Illustratively, the first insulating layer 12 has a relative dielectric constant of 2.25 and an outer diameter of 1.85mm. The material is polyethylene, and is the same as the third insulating layer 33 and the second insulating layer 22.

Illustratively, the third insulating layer 33 and the second insulating layer 22 are made of the same material and have a thickness of 0.3mm to 0.5mm.

In the embodiment of the present invention, the feeding coaxial cable 1 further includes a shielding layer 13 covering the first insulating layer 12.

Optionally, the shielding layer 13 may be a metal shielding mesh.

In an embodiment of the invention, the power line 2 is a high-security (Goubau) line, 10mm in length, two wavelengths in length.

In the embodiment of the present invention, the material of the conductive line 21 of the power line 2 may include copper.

The dielectric resonant antenna provided by the embodiment of the invention can radiate energy gathered on the surface and enhance the end-fire directivity. Based on this, referring to fig. 2, fig. 3 shows a dielectric resonator according to an embodiment of the present invention, which includes a square-shaped body 32, and a ring-shaped dielectric sleeve 31 fixed to the power line 2. Wherein:

alternatively, the dielectric constant of the body 32 and the annular dielectric sleeve 31 may be 8-10.

Illustratively, the bottom surface of the body 32 is 4mm by 5mm and the height is 2.5mm. The thickness of the annular media sleeve 31 is 0.1mm.

Annular medium cover 31 is fixed on body 32, and annular medium cover 31 encircles and fixes on the outer peripheral face of second insulating layer 22, and forms the semi-cylindrical groove through the mode of getting rid of on the body 32, the size in groove and the size looks adaptation of power line 2 to better mechanical fastening is convenient for. In the present embodiment, the first inner conductor 11, the conductive wire 21, and the second inner conductor 34 are coaxially disposed. The technical scheme of the embodiment of the invention can also bring the following beneficial effects: the dielectric resonant antenna provided by the embodiment of the invention has fewer integral components and simple structure.

The performance of the dielectric resonator antenna provided by the embodiment of the present invention is described below by using simulation results of the antenna.

Where the S11 reflection coefficient refers to the input return loss.

Referring to fig. 4, the vertical axis represents the S11 reflection coefficient of the feeder coaxial cable 1, and the horizontal axis represents the frequency of the source signal. As can be seen from FIG. 4, the S11 reflection coefficient is in the range of 50-70GHz with most frequencies below-10 decibels (dB) and a minimum of-40 dB, with the resonator height h as a parameter. And when h is 1.5mm and 2.5mm, the impedance bandwidth is wider, and the matching performance is better.

Referring to fig. 5 and 6, the highest gain achieved by simulation can be up to 10dBi. And the radiation pattern of the antenna, the maximum radiation direction, is constantly changed with the change of the frequency, fig. 5 and fig. 6 show the two-dimensional radiation patterns of the yoz plane at the frequency of 53GHz and 67GHz, respectively, and it is found that the different frequency deviation end-fire directions are different.

It should be understood that the above examples are only for clarity of illustration 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 therefrom are within the scope of the invention.

Claims

1. A dielectric resonator antenna, comprising: the feed coaxial cable (1), the power line (2), the dielectric resonator (3) and the conical shaft (4);

the input end of the feed coaxial cable (1) is used for connecting an information source;

the power line (2) is respectively connected with the output end of the feed coaxial cable (1) and the input end of the dielectric resonator (3); the power line (2) comprises a conductive line (21) and a second insulating layer (22) covering the conductive line (21), wherein the conductive line (21) is used for transmitting electromagnetic waves in a TM mode;

a second inner conductor (34) of the dielectric resonator (3) is electrically connected to the other end of the conductive line (21), and the dielectric resonator (3) further includes a third insulating layer (33) covering the second inner conductor (34); the dielectric resonator (3) comprises a body (32) which is square; the body (32) covers the half circumference of the third insulating layer (33);

the conical shaft (4) is wound on the periphery of the power line (2).

2. The dielectric resonator antenna according to claim 1, characterized in that the feeding coaxial cable (1) comprises a first inner conductor (11) and a first insulating layer (12) covering the first inner conductor (11), the first inner conductor (11) being electrically connected to one end of the conductive wire (21).

3. The dielectric resonator antenna of claim 2,

the feeding coaxial cable (1) further comprises a shielding layer (13) covering the first insulating layer (12);

the conical shaft (4) is connected with the periphery of the shielding layer (13).

4. A dielectric resonator antenna according to claim 1, characterized in that the body (32) is terminated by an annular dielectric sleeve (31); the annular medium sleeve (31) is suitable for sleeving and fixing the power line (2).

5. A dielectric resonator antenna according to claim 2, characterized in that the material of the first, second and third insulating layers (12, 22, 33) comprises polyethylene.

6. A dielectric resonator antenna according to claim 2, characterized in that the material of the first inner conductor (11), the conductive line (21) and the second inner conductor (34) comprises copper.

7. A dielectric resonator antenna according to claim 4, characterized in that the relative permittivity of the body (32) is the same as the relative permittivity of the annular dielectric sleeve (31).