Compact broadband circularly polarized magnetoelectric dipole array antenna applied to millimeter wave communication

Abstract

The invention discloses a compact broadband circularly polarized magnetoelectric dipole array antenna applied to millimeter wave communication, which comprises an upper layer dielectric plate and a lower layer dielectric plate which are connected through plastic screws, a metal radiation patch is adhered to the upper surface of the upper layer dielectric plate, a metal ground layer is arranged on the upper surface of the lower layer dielectric plate, a coupling gap is etched in the metal ground layer, and the coupling gap is communicated with the metal radiation patch. The bottom surface of the metal ground layer is provided with a U-shaped micro-strip feeder line, the terminal of the micro-strip feeder line is connected with a 50-ohm SMA connector, and the SMA connector is connected to the side edge of the lower dielectric plate. Parasitic patches are added during unit design, the working bandwidth of the antenna is improved, a sequential rotation method is used during 4 * 4 array forming, the lengths of feeder lines between feed networks are sequentially different, the 90-degree phase difference is generated between array elements, the necessary condition for forming circular polarization is generated, and the circular polarization characteristic of the whole antenna is greatly improved.

Description

Technical Field

[0001] This invention belongs to the field of magnetoelectric dipole antenna technology, specifically relating to a compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication. Background Technology

[0002] Traditional antennas, limited by narrow bandwidth, large size, and multipath interference, have hindered the practical application of high-frequency communication. As future integrated air-space-ground networks evolve towards millimeter-wave / terahertz frequencies, wideband circularly polarized antennas, due to their resistance to multipath interference and adaptive polarization characteristics, have become critical infrastructure for high-speed mobile platforms and dense environments. Magnetoelectric dipole antennas, with their complementary electric / magnetic dipole mechanism, naturally possess significant advantages such as strong anti-polarization interference capability, strong anti-multipath fading capability, and strong penetration capability. This makes them an ideal carrier for solving bandwidth limitations and polarization mismatch, providing next-generation hardware support for 6G communication, satellite terminals, and anti-interference systems.

[0003] Circularly polarized antenna technology is a technique for designing antennas so that the electric field vector of the electromagnetic waves radiated or received rotates with a constant amplitude in the direction of propagation. Unlike linearly polarized waves, circularly polarized waves can be decomposed into two linearly polarized components that are orthogonal in both space and time and have a 90-degree phase difference. Achieving circular polarization typically requires careful design of the antenna's geometry to excite two electric field components with equal amplitude and orthogonal phase in space. The core advantage of this type of antenna lies in its insensitivity to relative rotation between the transmitter and receiver; that is, regardless of how the antenna rotates around its axis, as long as the polarization rotation is matched, signal reception is essentially unaffected, as well as its excellent resistance to multipath reflections. Summary of the Invention

[0004] The purpose of this invention is to provide a compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication, which improves the circular polarization characteristics of the entire antenna.

[0005] The technical solution adopted in this invention is: A compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication includes an upper dielectric substrate and a lower dielectric substrate connected by plastic screws. A metal radiating patch is attached to the upper surface of the upper dielectric substrate, and a metal ground layer is disposed on the upper surface of the lower dielectric substrate. Coupling gaps are etched in the metal ground layer. A U-shaped microstrip feed line is disposed on the bottom surface of the metal ground layer. The terminal of the microstrip feed line is connected to a 50Ω SMA connector, which is connected to the side of the lower dielectric substrate.

[0006] The invention is further characterized by: The metallic radiation patch consists of 16 pairs of centrally symmetrical C-shaped patches.

[0007] Parasitic patches are also attached to the upper surface of the upper medium plate. Two parasitic patches are provided on the edge of each pair of C-type patches, and the parasitic patches close to each pair of C-type patches are arranged in a centrally symmetrical manner.

[0008] The upper dielectric substrate uses a Rogers RT / duroid 5880 dielectric substrate with a dielectric constant of 3.55.

[0009] The lower dielectric substrate uses Rogers RO4003 dielectric substrate with a dielectric constant of 2.2.

[0010] The coupling gap is set to a "Z" shaped gap.

[0011] The metallic layer is set as a copper sheet.

[0012] The upper and lower dielectric substrates are the same size.

[0013] The beneficial effects of this invention are: This invention relates to a compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication. Sixteen pairs of centrally symmetrical C-shaped dipole radiating elements are integrated on the upper surface of the upper dielectric substrate. Two parasitic patches are added around each radiating element. Below each radiating patch are two metal vias that traverse the upper dielectric. The radiating patches are vertically connected to the intermediate metal ground layer via these metallized vias. The intermediate metal ground layer serves as the reflector layer for the upper antenna and the ground layer for the lower microstrip feed line. Z-shaped coupling slots are etched on its surface, and interlayer coupling is controlled through symmetrically distributed metallized vias on both sides of the slots. The lower layer employs a microstrip line feed network, with the middle section of the feed line connected to a 50Ω microstrip line to achieve characteristic impedance matching. Finally, the antenna generates circularly polarized radiation characteristics through a slot-coupled feeding mechanism. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the compact broadband circularly polarized magnetoelectric dipole array antenna of the present invention applied to millimeter-wave communication; Figure 2 This is an evolution diagram of the compact broadband circularly polarized magnetoelectric dipole array antenna element applied to millimeter-wave communication according to the present invention; Figure 3a This is a comparison diagram of the antenna impedance bandwidth S-parameter in the compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication, which is an application of the present invention. Figure 3b This is a gain comparison diagram of the compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication based on the present invention; Figure 3c This is a comparison diagram of the axial ratio of the compact broadband circularly polarized magnetoelectric dipole array antenna of the present invention applied to millimeter-wave communication; Figure 4This is a physical image of the compact broadband circularly polarized magnetoelectric dipole array antenna of the present invention applied to millimeter-wave communication; Figure 5 This invention relates to a compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication. S Measured and simulated graphs of parameters varying with frequency; Figure 6 This is a measured and simulated graph showing the gain of the compact broadband circularly polarized magnetoelectric dipole array antenna of the present invention as a function of frequency, applied to millimeter-wave communication. Figure 7 This is a measured and simulated diagram of the axial ratio of the compact broadband circularly polarized magnetoelectric dipole array antenna applied to millimeter-wave communication, as a function of frequency. Figure 8 This is a comparison of the measured and simulated center frequency radiation pattern of the compact broadband circularly polarized magnetoelectric dipole array antenna of the present invention applied to millimeter-wave communication. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0017] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0018] This invention relates to a compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication, comprising an upper dielectric substrate and a lower dielectric substrate connected by plastic screws. A metal radiating patch is attached to the upper surface of the upper dielectric substrate, and a metal ground layer is disposed on the upper surface of the lower dielectric substrate. Coupling gaps are etched into the metal ground layer, and a U-shaped microstrip feed line is disposed on the bottom surface of the metal ground layer. The terminal of the microstrip feed line is connected to a 50Ω SMA connector, which is connected to the side of the lower dielectric substrate.

[0019] Example 1 A compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication includes an upper dielectric substrate and a lower dielectric substrate connected by plastic screws. A metal radiating patch is attached to the upper surface of the upper dielectric substrate, and a metal ground layer is disposed on the upper surface of the lower dielectric substrate. Coupling gaps are etched in the metal ground layer. A U-shaped microstrip feed line is disposed on the bottom surface of the metal ground layer. The terminal of the microstrip feed line is connected to a 50Ω SMA connector, which is connected to the side of the lower dielectric substrate.

[0020] The metallic radiating patch consists of 16 pairs of centrally symmetrical C-shaped patches. Two metal vias are located beneath each C-shaped patch, and these vias are located on the upper dielectric substrate.

[0021] Example 2 A compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication includes an upper dielectric substrate and a lower dielectric substrate connected by plastic screws. A metal radiating patch is attached to the upper surface of the upper dielectric substrate, and a metal ground layer is disposed on the upper surface of the lower dielectric substrate. Coupling gaps are etched in the metal ground layer. A U-shaped microstrip feed line is disposed on the bottom surface of the metal ground layer. The terminal of the microstrip feed line is connected to a 50Ω SMA connector, which is connected to the side of the lower dielectric substrate.

[0022] The metallic radiation patch consists of 16 pairs of centrally symmetrical C-shaped patches.

[0023] Parasitic patches are also attached to the upper surface of the upper medium plate. Two parasitic patches are provided on the edge of each pair of C-type patches, and the parasitic patches close to each pair of C-type patches are arranged in a centrally symmetrical manner.

[0024] The upper dielectric substrate uses a Rogers RT / duroid 5880 dielectric substrate with a dielectric constant of 3.55.

[0025] The lower dielectric substrate uses Rogers RO4003 dielectric substrate with a dielectric constant of 2.2.

[0026] Example 3 A compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication includes an upper dielectric substrate and a lower dielectric substrate connected by plastic screws. A metal radiating patch is attached to the upper surface of the upper dielectric substrate, and a metal ground layer is disposed on the upper surface of the lower dielectric substrate. Coupling gaps are etched in the metal ground layer. A U-shaped microstrip feed line is disposed on the bottom surface of the metal ground layer. The terminal of the microstrip feed line is connected to a 50Ω SMA connector, which is connected to the side of the lower dielectric substrate.

[0027] The metallic radiation patch consists of 16 pairs of centrally symmetrical C-shaped patches.

[0028] Parasitic patches are also attached to the upper surface of the upper medium plate. Two parasitic patches are provided on the edge of each pair of C-type patches, and the parasitic patches close to each pair of C-type patches are arranged in a centrally symmetrical manner.

[0029] The upper dielectric substrate uses a Rogers RT / duroid 5880 dielectric substrate with a dielectric constant of 3.55.

[0030] The lower dielectric substrate uses Rogers RO4003 dielectric substrate with a dielectric constant of 2.2.

[0031] The coupling gap is set to a "Z" shaped gap.

[0032] The metallic layer is set as a copper sheet.

[0033] The upper and lower dielectric substrates are the same size.

[0034] Example 4 like Figure 1 As shown, the compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication consists of two parts: an upper dielectric substrate as the radiating layer, and a metal patch on its upper surface, such as... Figure 1 As shown in (a), it consists of 16 pairs of centrally symmetrical C-type patches. The lower dielectric substrate is the feed layer, and its upper surface is the ground layer, as shown in [example image]. Figure 1 As shown in (b), the surface is covered with copper, and 16 coupling slots are etched on the copper. Two metal vias are distributed on both sides of each coupling slot to facilitate the feeding of the feed layer to the radiating layer. The feed network is designed using the sequential rotation method, and the feed network is as follows: Figure 1 As shown in (c), by sequentially altering the lengths of the feed lines, a 90° phase difference is created between each array element, providing the necessary conditions for circular polarization. The microstrip line terminals are connected to 50Ω SMA connectors. The upper and lower dielectric substrates are integrally fixed using plastic screws with a radius of R4. The overall model is as follows. Figure 1 As shown in (d).

[0035] The upper dielectric substrate uses a Rogers RT / duroid 5880 dielectric substrate with a dielectric constant of 2.2 and a thickness of [thickness value missing]. H1. The dimensions of the upper dielectric substrate are: W × W The upper surface has 4×4 radiating patches, and the length of the main radiating patch is... L 3, width is L 2. The diameter of the through hole is R 1. The length of the parasitic patch is S 1, width is S 2. The two main radiating patches are centrally symmetrically distributed, as are the two parasitic patches. The lower dielectric substrate is a Rogers RO4003 dielectric substrate with a dielectric constant of 3.55 and a thickness of [thickness missing]. H 2. The dimensions of the dielectric substrate are: W × W The length of the coupling slot is L s Width is W s The antenna features 4×4 Z-shaped slots, which are Z-shaped slots etched onto the metal (copper) sheet on the upper surface of the lower dielectric substrate. The lower surface of the lower dielectric substrate forms the feed network, which consists of 4×4 U-shaped microstrip lines rotated in sequence. The circularly polarized magnetoelectric dipole array antenna is side-fed with one feed port, and the feed line terminal is connected to a 50Ω SMA connector.

[0036] Example 5 like Figure 2 The diagram shows the evolution of the antenna design. This invention's antenna element starts with a common linearly polarized magnetoelectric dipole antenna structure: a pair of rectangular printed electric dipoles orthogonally arranged with an equivalent magnetic dipole formed by slots in the intermediate metal layer. Connecting the narrow coupling slots with metallized vias enables equal-amplitude excitation of the two arms of the electric dipoles. To generate CP radiation, orthogonal electric field components are introduced. Branches are added to the original rectangular patches along the x and y directions to generate a vertically polarized wave with a 90° phase difference from the reference polarized wave, i.e., the C-type circularly polarized magnetoelectric dipole antenna structure shown in Ant. 1. However, the AR bandwidth is too narrow to meet the design requirements. To achieve a wider axial ratio bandwidth, this invention employs a composite CP method, adding two rectangular parasitic patches along the +45° diagonal to introduce an additional resonant point, forming a new circularly polarized magnetoelectric dipole antenna structure as shown in Ant. 2. To achieve better AR bandwidth, the rectangular parasitic patch is cut into a polygonal parasitic patch based on Ant.2, as shown in Ant.3.

[0037] Figure 3 compares the performance metrics of Ant.1 to Ant.3. Figure 3(a) and (b) show the antenna impedance bandwidth. S 11 The comparison of gain and performance shows, as can be seen from the above comparison chart, that after loading the symmetrical parasitic patch, S 11With an impedance bandwidth of 27.2% and a maximum gain of 8dBi, Figure 3(c) shows the axial ratio comparison. Without changing the impedance bandwidth and gain, the antenna AR bandwidth increased from 2.44GHz to 4.43GHz, and the relative bandwidth increased from 9.4% to 16.52%, representing a 7.12% increase compared to Ant.1. Because the magnetoelectric dipole structure can radiate CP waves, the parasitic patch, through near-field coupling with the electric and magnetic dipoles, excites additional resonant modes. When the resonant frequency of the parasitic patch is adjacent to the resonant point of the main structure, the impedance characteristics are superimposed, effectively combining to form a wider -10dB impedance bandwidth and a 3dB axial ratio bandwidth, thus verifying the importance of the parasitic patch in broadening the AR bandwidth. To further broaden the AR bandwidth, the parasitic patch was chamfered. This chamfering changed the direction of the surface current, resulting in an AR bandwidth of 19.6% for Ant.3, a 3.08% increase in relative bandwidth compared to Ant.2.

[0038] Example 6 like Figure 4 As shown, a physical diagram of the antenna is provided. Figure 5 Given S The graph compares the simulated and measured parameters as a function of frequency. From the graph, we can see that the antenna simulation... S The parameters are basically consistent with the actual measurements. Figure 6 A comparison graph of simulation and actual measurement of gain as a function of frequency is presented. It can be seen from the graph that the measured gain is relatively stable within the operating frequency band, and the similarity between the actual measurement and the simulation is very high. Figure 7 The simulation and measured comparison graphs of axial ratio as a function of frequency are presented. It can be seen from the graphs that the array antenna is still a circularly polarized antenna in the frequency band, which is the same as the simulation. Figure 8 The simulation and measured radiation pattern at the center frequency are presented. The difference between the main polarization and the cross polarization is -28.5dB, which shows that the antenna has good polarization characteristics within the frequency band.

[0039] This invention relates to a compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication. Parasitic patches are added during the element design to improve the antenna's operating bandwidth. When performing a 4×4 array, a sequential rotation method is used to ensure that the lengths of the feed lines between the feed networks differ sequentially, resulting in a 90° phase difference between each array element. This creates the necessary conditions for circular polarization and greatly improves the circular polarization characteristics of the entire antenna.

Claims

1. A compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication, characterized in that, The device includes an upper dielectric substrate and a lower dielectric substrate connected by plastic screws. A metal radiating patch is attached to the upper surface of the upper dielectric substrate, and a metal ground layer is disposed on the upper surface of the lower dielectric substrate. Coupling gaps are etched in the metal ground layer. A U-shaped microstrip feed line is disposed on the bottom surface of the metal ground layer. The end of the microstrip feed line is connected to a 50Ω SMA connector, which is connected to the side of the lower dielectric substrate.

2. The compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication according to claim 1, characterized in that, The metal radiation patch consists of 16 pairs of centrally symmetrical C-shaped patches.

3. The compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication according to claim 1, characterized in that, The upper surface of the upper medium plate is also attached with parasitic patches. Each pair of C-type patches has two parasitic patches on its edge, and the parasitic patches close to each pair of C-type patches are arranged in a centrally symmetrical manner.

4. The compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication according to claim 1, characterized in that, The upper dielectric substrate is a Rogers RT / duroid 5880 dielectric substrate with a dielectric constant of 3.

55.

5. The compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication according to claim 1, characterized in that, The lower dielectric substrate is a Rogers RO4003 dielectric substrate with a dielectric constant of 2.

2.

6. The compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication according to claim 1, characterized in that, The coupling gap is set as a "Z" shaped gap.

7. The compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication according to claim 1, characterized in that, The metallic layer is set as a copper sheet.

8. The compact broadband circularly polarized magnetoelectric dipole array antenna for millimeter-wave communication according to claim 1, characterized in that, The upper and lower dielectric substrates are the same size.

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