CN114421164B - Low-profile magnetoelectric dipole antenna unit based on artificial surface plasmon and frequency scanning array - Google Patents

Abstract

The invention provides a low-profile magnetoelectric dipole antenna unit and a frequency scanning array based on artificial surface plasmons, which relate to the electronic field and the technical field of wireless communication, and comprise a magnetoelectric dipole radiation structure and a coplanar waveguide feed structure, wherein the magnetoelectric dipole radiation structure feeds through the coplanar waveguide feed structure; the magnetoelectric dipole radiation structure comprises an artificial surface plasmon transmission line of a horizontal structure and a three-dimensional artificial surface plasmon transmission line structure which is in a shape of an opening convex letter, the artificial surface plasmon transmission line of the horizontal structure radiates as an electric dipole, and the three-dimensional artificial surface plasmon transmission line structure which is positioned in the middle of the artificial surface plasmon transmission line of the horizontal structure radiates as a magnetic dipole, so that the low profile and miniaturization of the magnetoelectric dipole antenna are realized. The magnetoelectric unit structure is periodically extended along the axial direction to form a series-fed frequency scanning antenna array, beam scanning with a larger angle is realized in a bandwidth range, and the boundary of the scanning range is close to the side-emitting direction.

Description

Low Profile Magnetoelectric Dipole Antenna Element and Frequency Sweep Based on Artificial Surface Plasmon array

technical field

The present invention relates to the field of electronics and wireless communication technology, in particular to a low-profile magnetoelectric dipole antenna design based on artificial surface plasmon polaritons and a frequency-swept array.

Background technique

With the rapid development of wireless communication technology and limited installation space, in order to ensure the smooth evolution of existing networks and services, existing wireless communication systems usually require magnetoelectric dipole antennas with a low profile , however, limited by the working principle of the magnetoelectric dipole, the design profile of most magnetoelectric dipole antennas is usually around 0.25λ, so this requirement significantly increases the difficulty of antenna design.

Document 1 (A. Chlaviin announced a new type of antenna with the same E-plane and H-plane pattern, Transactions of the IRE Professional Group on Antennas and Propagation, 1954, 2( 3): 113-119) for the first time proposed the feasibility of the theory of complementary pattern based on two kinds of dipoles.

Document 2 (K.M.Luk, H.Wong) disclosed a novel broadband unidirectional antenna [J]. International Journal of Microwave and Optical Technology, 2006, 1(1 ):35-44) designed a magnetoelectric dipole antenna working in one polarization, by using a Γ-type probe to simultaneously excite a pair of horizontal patches and vertical short-circuit patches Dipole radiation, however, the overall size of the unit is 0.64λ×0.5λ×0.25λ, the size is large and the feeding is complicated, which is not conducive to forming a scanning array.

Afterwards, for this type of antenna, experts, scholars and engineering technicians in related fields conducted extensive research and obtained a series of technical achievements. However, as far as the disclosed related magnetoelectric dipole antenna technology and structure , there are still the following problems.

First of all, most of these improvements focus more on increasing the impedance bandwidth of this type of antenna. Although many low-profile miniaturized designs have been carried out, the profiles are mostly greater than 0.1λ. Secondly, in order to maintain good performance, most of the currently disclosed magnetoelectric dipole antennas have complex feeding structures, difficult processing, and are not easy to form large-angle scanning arrays. It can be seen that how to realize low-profile magnetoelectric dipoles, a simple feeding method, and its application in large-angle scanning arrays are problems to be solved urgently by people in the industry.

According to the retrieval of existing technical patent literature, the Chinese invention patent publication number is CN111262005A, which discloses a dual-polarized broadband magnetoelectric dipole antenna unit and antenna array suitable for 5G base stations, belonging to the technical field of mobile communication base station antennas, not only Dual polarization is achieved, and it has the advantages of miniaturization, wide frequency band, large gain, small back lobe, stable pattern, and high isolation, which can fully meet the needs of modern 5G communication base stations. Including metal box reflective structure and magnetoelectric dipole, feed structure, metal box structure includes metal bottom plate, magnetoelectric dipole includes a plurality of magnetoelectric dipole units distributed symmetrically and at intervals, each magnetoelectric dipole Each unit includes an upper dielectric substrate and a parallel dielectric plate below it. Metal patches are printed on the dielectric layer on the surface of the upper dielectric substrate as electric dipoles. The parallel dielectric plate is provided with a metal coating, a metal coating and a metal The base plate together forms a magnetic dipole; the feeding structure includes a pair of orthogonally arranged feeder lines, and the bottom of each feeder line is connected with a coaxial line laid through the metal base plate. However, the present invention provides a small-sized component mounting structure, which solves the problem of insufficient internal space of the narrow-shaped vehicle lamp. Therefore, the method introduced in this document and the present invention belongs to different inventive concepts.

Contents of the invention

In view of the defects in the prior art, the object of the present invention is to provide a low-profile magnetoelectric dipole antenna unit and a frequency-sweeping array based on artificial surface plasmons.

A low-profile magnetoelectric dipole antenna unit based on artificial surface plasmons provided by the present invention includes a magnetoelectric dipole radiation structure and a coplanar waveguide feeding structure, and the coplanar waveguide feeding structure is located at the magnetoelectric At one end of the dipole radiating structure, the magnetoelectric dipole radiating structure is fed through the coplanar waveguide feeding structure;

The magnetoelectric dipole radiation structure includes a horizontal artificial surface plasmon transmission line structure and a three-dimensional artificial surface plasmon transmission line structure. The three-dimensional artificial surface plasmon transmission line structure is located between the horizontal artificial surface plasmon transmission line In the middle, the horizontal structure of the artificial surface plasmon transmission line radiates as an electric dipole, and the three-dimensional artificial surface plasmon transmission line structure radiates as a magnetic dipole.

In some embodiments, the magnetoelectric dipole radiating structure is formed by bending a good conductor, and the bending angle is 90°.

In some embodiments, a diamond patch is also included. The diamond patch is located in the center of one side of the artificial surface plasmon transmission line of the horizontal structure close to the coplanar waveguide feeding structure. An imbalance in the energy radiated by dipoles.

In some embodiments, the gradually changing groove depth is located on the side of the artificial surface plasmon transmission line of the horizontal structure close to the coplanar waveguide feeding structure, and the gradually changing groove depth enables better energy transmission into the magnetoelectric dipole radiation structure.

In some embodiments, the three-dimensional artificial surface plasmon transmission line structure is in a convex shape with openings.

In some embodiments, the current direction of the three-dimensional artificial surface plasmon transmission line structure is in the shape of an open current loop.

The present invention also provides a low-profile magnetoelectric dipole frequency-sweep array based on artificial surface plasmons, including a low-profile magnetoelectric dipole antenna unit based on artificial surface plasmons.

In some embodiments, the magnetoelectric dipole radiation structure is periodically expanded and connected in the axial direction to form a series feed array, and the coplanar waveguide feed structure excites the series feed array, and the coplanar waveguide feed structures are respectively located at the ends of the series feed array sides.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The present invention realizes the lower section of the magnetoelectric dipole through the radiation structure of the magnetoelectric dipole, and reduces the overall size of the antenna;

(2) The present invention forms a serial feed array through a magnetoelectric dipole radiation structure, which has frequency sweep characteristics, and can realize beam scanning in a relatively large angle range, and the boundary of the beam scanning range is close to the side-firing direction;

(3) The antenna of the present invention uses a coplanar waveguide for direct feeding, which reduces the manufacturing cost, and has a simple overall structure and is easy to process.

Description of drawings

Other characteristics, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

FIG. 1 is an overall schematic diagram of a low-profile magnetoelectric dipole antenna unit based on artificial surface plasmons provided by an embodiment of the present invention;

2 is a side view of a low-profile magnetoelectric dipole antenna unit based on artificial surface plasmons provided by an embodiment of the present invention;

3 is a top view of a low-profile magnetoelectric dipole antenna unit based on artificial surface plasmons provided by an embodiment of the present invention;

Fig. 4 is a current amplitude distribution diagram of the antenna at 2.85 GHz when the input port is excited according to an embodiment of the present invention;

FIG. 5 is an overall diagram of the vector current distribution of the antenna at 2.85 GHz when the input port is excited according to an embodiment of the present invention;

6 is a side view of the vector current distribution of the antenna at 2.85 GHz when the input port is excited according to an embodiment of the present invention;

Fig. 7 is the reflection coefficient simulation result of the unit antenna input port in the embodiment of the present invention;

FIG. 8 is a simulation result of the pattern of the embodiment of the present invention on the azimuth planes of phi=0° and phi=90° at 2.7 GHz.

FIG. 9 is a simulation result of the pattern of the embodiment of the present invention on the azimuth planes of phi=0° and phi=90° at 2.85 GHz.

FIG. 10 is a simulation result of the pattern of the embodiment of the present invention on the azimuth planes of phi=0° and phi=90° at 3GHz.

FIG. 11 is an overall schematic diagram of a low-profile magnetoelectric dipole frequency-swept antenna array based on artificial surface plasmons provided by an embodiment of the present invention.

Fig. 12 is a side view of a low-profile magnetoelectric dipole frequency-swept antenna array based on artificial surface plasmons provided by an embodiment of the present invention.

Fig. 13 is a simulation result of the reflection coefficient of the input port of the frequency-swept array antenna and the transmission coefficient of two ports provided by the embodiment of the present invention.

FIG. 14 shows the simulation results of the pattern of the frequency-swept array antenna provided by the embodiment of the present invention on the phi=90° azimuth plane at 2.4GHz, 2.5GHz, 2.6GHz, 2.7GHz, 2.8GHz, 2.9GHz, and 3GHz.

Fig. 15 shows the variation of the maximum gain angle on the azimuth plane of phi=90° in the 2.3GHz-3GHz frequency band of the frequency-swept array antenna provided by the embodiment of the present invention.

Fig. 16 shows the variation of the maximum array gain of the frequency-swept array antenna provided by the embodiment of the present invention in the 2.3GHz-3GHz frequency band.

Labels in the figure:

Magnetoelectric dipole radiation structure 1, artificial surface plasmon transmission line with horizontal structure 11, three-dimensional artificial surface plasmon transmission line structure 12, coplanar waveguide feeding structure 2, diamond-shaped patch 3, groove depth gradient 4, Series feed array 5.

Detailed ways

The present invention will be described in detail below in conjunction with specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

Example 1

A low-profile magnetoelectric dipole antenna unit based on artificial surface plasmons provided by the present invention, as shown in Figures 1-3, includes a magnetoelectric dipole radiation structure 1, a coplanar waveguide feed structure 2, The diamond-shaped patch 3 and the groove depth gradient 4, the coplanar waveguide feeding structure 2 is located at one end of the magnetoelectric dipole radiating structure 1, and the magnetoelectric dipole radiating structure 1 is fed through the coplanar waveguide feeding structure 2. Wherein, the magnetoelectric dipole radiation structure 1 is bent 90° by a good conductor, and the magnetoelectric dipole radiation structure 1 expands periodically along the axial direction.

The magnetoelectric dipole radiation structure 1 includes an artificial surface plasmon transmission line 11 with a horizontal structure and a three-dimensional artificial surface plasmon transmission line structure 12 in a convex shape with an opening. The three-dimensional artificial surface plasmon transmission line structure 12 is located in the horizontal The artificial surface plasmon of the structure is in the middle of the transmission line 11 . The artificial surface plasmon transmission line 11 of the horizontal structure radiates as an electric dipole; the three-dimensional artificial surface plasmon transmission line structure 12 radiates as a magnetic dipole. Preferably, the current direction is in the shape of an open current loop.

The diamond-shaped patch 3 is connected to the center of one side of the artificial surface plasmon transmission line 11 of the horizontal structure close to the coplanar waveguide feeding structure 2, and the diamond-shaped patch 3 compensates for the loss of electric dipole radiation energy caused by the gradual change of the groove depth 4 unbalanced. The groove depth gradient 4 is located on the side of the horizontal artificial surface plasmon transmission line 11 close to the coplanar waveguide feeding structure 2 , and the groove depth gradient 4 enables better energy transmission into the magnetoelectric dipole radiation structure 1 .

More specifically, as shown in Figures 4-6, the magnetoelectric dipole radiation structure 1 with slow wave characteristics is bent at right angles multiple times, so that the formed unit has a "convex" opening at a center frequency of 2.85 GHz The current distribution on the type three-dimensional artificial surface plasmon transmission line structure 12 is similar to an open current loop with a clockwise current direction, and radiates as a magnetic dipole. The horizontal artificial surface plasmon transmission line 11 on both sides of the unit has the same current direction on the structure, and radiates as a pair of electric dipoles. In this implementation case, the artificial surface plasmon transmission line used is fed by a coplanar waveguide, and the slot depth gradient 4 of the artificial surface plasmon transmission line near the feeding side is gradually designed to expand the working of the antenna. bandwidth. A rhombic patch 3 is attached to the center of the artificial surface plasmon transmission line 11 structure of the horizontal structure near the feeding side to compensate for the asymmetry of the radiated energy at both ends of the electric dipole caused by the gradient of the groove depth 4 .

Accompanying drawings 7 to 10 show the relevant performance simulation parameters of the example antenna. It can be seen from the simulation results that the antenna works well in the 2.73GHz-2.97GHz frequency band, and the relative impedance bandwidth is 8.4%. The antenna has obvious magnetic and electric dipole working characteristics, high antenna gain (8.5-9dBi), low back lobe radiation, and the unit is on the E plane (phi=90°) and H plane (phi=0°) The above pattern is more symmetrical. The reason why the main lobe of the E-plane pattern of the unit is shifted is mainly because in order to transmit energy better, the artificial surface plasmon transmission line groove depth gradient design on the side of the unit near the feeder is designed gradually, which destroys the power supply. The balance of radiated energy across a dipole.

Example 2

The present invention also provides a frequency-swept array of low-profile magnetoelectric dipoles based on artificial surface plasmons, as shown in Figures 11-12, including low-profile magnetoelectric dipoles based on artificial surface plasmons Antenna unit. Multiple magnetoelectric dipole radiation structures 1 are connected in series to form a series feed array 5 , and the coplanar waveguide feed structure 2 excites the series feed array 5 , and the coplanar waveguide feed structures 2 are respectively located on both sides of the end of the series feed array 5 . Preferably, the coplanar waveguide feeding structure 5 is realized by printed circuit board technology, and the series fed array 5 is realized by connecting five magnetoelectric dipole radiation structures 1 to each other, and the structure is formed by bending a good conductor.

More specifically, accompanying drawings 13 to 16 show the relevant performance simulation parameters of the frequency-swept array antenna. It can be seen from the simulation results that the frequency-swept array antenna has good impedance performance at 2.4GHz-3GHz, relatively The working bandwidth is 22.2%, the active reflection coefficient of the port is <-10dB, and the isolation between ports is >10dB. The array can achieve 54° beam scanning in this frequency band, and the array gain is >8dBi. In 2.4-2.7GHz, the array scans at a relatively stable rate (120°/GHz), while in 2.7-3GHz, due to the increasing beam The scanning rate slows down when approaching the side-firing direction of the array, but beam scanning within a certain angular range can still be achieved.

In the description of this application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", The orientation or positional relationship indicated by "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description, rather than indicating or implying the referred device Or elements must have a certain orientation, be constructed and operate in a certain orientation, and thus should not be construed as limiting the application.

Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. In the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims (7)

1. A low-profile magnetoelectric dipole antenna unit based on artificial surface plasmons is characterized by comprising a magnetoelectric dipole radiation structure (1) and a coplanar waveguide feed structure (2), wherein the coplanar waveguide feed structure (2) is positioned at one end of the magnetoelectric dipole radiation structure (1), and the magnetoelectric dipole radiation structure (1) feeds through the coplanar waveguide feed structure (2);

the magnetoelectric dipole radiation structure (1) comprises an artificial surface plasmon transmission line (11) with a horizontal structure and a stereoscopic artificial surface plasmon transmission line structure (12), wherein the stereoscopic artificial surface plasmon transmission line structure (12) is positioned in the middle of the artificial surface plasmon transmission line (11) with the horizontal structure, the artificial surface plasmon transmission line (11) with the horizontal structure is used as an electric dipole for radiation, and the stereoscopic artificial surface plasmon transmission line structure (12) is used as a magnetic dipole for radiation;

the three-dimensional artificial surface plasmon transmission line structure (12) is in an open convex shape.

2. The artificial surface plasmon based low-profile magnetoelectric dipole antenna unit according to claim 1, wherein said magnetoelectric dipole radiating structure (1) is formed by bending a good conductor at an angle of 90 °.

3. The artificial surface plasmon based low-profile magnetoelectric dipole antenna unit according to claim 2, further comprising a rhombic patch (3), wherein the rhombic patch (3) is located in the center of one side of the horizontal structure artificial surface plasmon transmission line (11) close to the coplanar waveguide feed structure (2), and the rhombic patch (3) compensates for the imbalance of electric dipole radiation energy caused by gradual groove depth variation (4).

4. The artificial surface plasmon based low-profile magnetoelectric dipole antenna unit according to claim 3, wherein said groove depth gradations (4) are located on the side of the artificial surface plasmon transmission line (11) of the horizontal structure near the coplanar waveguide feed structure (2), said groove depth gradations (4) enable better energy transmission into the magnetoelectric dipole radiating structure (1).

5. The artificial surface plasmon based low-profile magnetoelectric dipole antenna unit according to claim 1, wherein the current trend of the stereoscopic artificial surface plasmon transmission line structure (12) is open current ring-shaped.

6. A low-profile magnetoelectric dipole frequency scanning array based on artificial surface plasmons is characterized by comprising the low-profile magnetoelectric dipole antenna unit based on artificial surface plasmons of any one of claims 1 to 5.

7. The artificial surface plasmon based low-profile magnetoelectric dipole frequency scanning array according to claim 6, wherein the magnetoelectric dipole radiation structures (1) are periodically extended and connected in an axial direction to form a series feed array (5), the coplanar waveguide feed structure (2) excites the series feed array (5), and the coplanar waveguide feed structures (2) are respectively positioned on two sides of the end of the series feed array (5).

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