A millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna

Abstract

The present invention discloses a millimeter-wave differentially fed dual-polarized wide-beam magnetoelectric dipole antenna. The antenna comprises four square metal patches, a differential coaxial feeding structure, four groups of metal vias, a dielectric substrate, a metal floor and a vertical metal fence; the differential coaxial feeding structure comprises a cross-shaped metal patch and four feeding coaxial lines under the metal floor. The present invention adopts the form of differential dual-polarized coaxial feeding, and has the characteristics of low cross-polarization and good polarization diversity capability. By adding vertical metal column fences around the magnetoelectric dipole antenna, it has the characteristics of a wide beam. The present invention can be applied to linear phased arrays, and the bandwidth can cover the 5G millimeter-wave frequency band.

Description

Technical Field

[0001] The invention relates to the technical field of wireless mobile communications, and in particular to a millimeter wave differential feeding dual-polarization wide-beam magneto-electric dipole antenna. Background Art

[0002] With the development of wireless communication technology, the performance requirements for antennas are getting higher and higher. In modern wireless systems, dual-polarized antennas have become a hot topic of current research because of their good polarization diversity capabilities, which can increase channel capacity and improve spectrum efficiency. Compared with traditional mechanical scanning antennas, phased array antenna scanning has the characteristics of fast scanning speed, small size, and good stability; since the total directional pattern of the array antenna is the product of the active unit directional pattern and the array factor, in order to make the array have a relatively small gain flatness during the scanning process, the more commonly used method to increase the array scanning angle is to design antenna units with wide beam active directional pattern characteristics. The differential antenna uses balanced feeding, which reduces the use of balun. Compared with the traditional single-port antenna, it has the advantages of reducing energy loss and improving system efficiency. In 2015, Mingjian Li, Kwai-Man Luk and others published an article titled "Wideband Magneto-Electric Dipole Antenna for 60-GHz Millimeter-Wave Communications" in "IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION". They used L-type probe single polarization feeding and achieved a relative bandwidth of 51% at 60GHz through the broadband characteristics of magneto-electric dipole. The antenna has the advantages of simple structure and easy processing, but due to the large cross polarization caused by the feeding probe and the small beam width, the unit antenna cannot be well applied to millimeter wave phased array antennas.

[0003] There may not be any millimeter-wave magneto-electric dipole antenna with differential feeding, dual polarization and wide beam at the same time now, so it is necessary to design a differentially fed dual polarization wide beam magneto-electric dipole antenna. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and provide a millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna. The antenna adopts a cross-shaped metal feeding patch structure, realizes differential feeding and dual polarization at the same time, and has the characteristics of low cross-polarization and good polarization diversity capability; by adding a vertical metal column fence around the magneto-electric dipole antenna, a vertical current is introduced, and the beams of the vertical metal column and the magneto-electric dipole antenna are superimposed, which has the characteristics of a wide beam. The unit can be used in a linear phased array, and the bandwidth can cover the 5G millimeter wave (24.25-27.5GHz) frequency band.

[0005] The purpose of the present invention is achieved by at least one of the following technical solutions.

[0006] A millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna, comprising four square metal patches, a differential coaxial feeding structure, four groups of metal vias, a dielectric substrate, a metal floor and a vertical metal fence; the differential coaxial feeding structure comprises a cross-shaped metal patch and four feeding coaxial lines located under the metal floor;

[0007] Four square metal patches are arranged on the upper layer of the dielectric substrate and are bonded to the upper surface of the dielectric substrate; the metal floor is arranged on the lower layer of the dielectric substrate and is bonded to the lower surface of the dielectric substrate; a cross-shaped metal patch is arranged in the middle of the four square metal patches; the outer conductors of the four feeding coaxial lines are all connected to the metal floor, and the inner conductors of the four feeding coaxial lines extend into the dielectric substrate and are respectively connected to one end of the cross-shaped metal patch; four groups of metal vias are arranged in the dielectric substrate, and each group of metal vias is respectively connected to the edge of a square metal patch and the metal floor; the vertical metal fence is located in the dielectric substrate.

[0008] Furthermore, the material of the dielectric substrate is Rogers 5880.

[0009] Furthermore, the thickness of the dielectric substrate is 1.2-1.5 mm.

[0010] Furthermore, the four square metal patches are arranged in a 2×2 pattern in the center of the upper layer of the dielectric substrate.

[0011] Furthermore, each group of metal vias includes three cylindrical metal vias, and the three cylindrical metal vias are located at the inner corners of the square metal patch connected thereto.

[0012] Furthermore, the four square metal patches respectively form two pairs of electric dipoles, and the four groups of metal vias respectively form two pairs of magnetic dipoles according to the corresponding square metal patches, and finally form two pairs of magneto-electric dipoles, which are called magneto-electric dipole antennas.

[0013] Furthermore, the cross-shaped metal patch is a cross-shaped metal feeding patch structure, and 0° and 90° dual-polarization differential feeding is realized on the cross-shaped metal patch through four feeding coaxial lines, and energy is transmitted to two pairs of magnetoelectric dipoles through coupled feeding, which has broadband characteristics.

[0014] Furthermore, the vertical metal fence includes a plurality of vertical fence metal posts surrounding two pairs of magneto-electric dipoles. By adding a vertical metal fence around the magneto-electric dipole antenna, a vertical current is introduced, and the beams of the vertical fence metal posts and the magneto-electric dipole antenna are superimposed, which has the characteristics of a wide beam.

[0015] Furthermore, the height of the vertical fence metal posts is flush with the thickness of the dielectric substrate.

[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0017] 1. Compared with the existing millimeter-wave magnetoelectric dipole antenna, the antenna of the present invention adopts a cross-shaped metal feeding patch, realizes differential feeding and dual polarization at the same time, has the characteristics of low cross-polarization and good polarization diversity capability, and the cross-polarization gain of the E-plane and H-plane is about -40dBi in the entire frequency band.

[0018] 2. Compared with the existing millimeter-wave magnetoelectric dipole antenna, the antenna unit of the present invention introduces vertical current by adding metal pillars around the magnetoelectric dipole antenna, and the beams of the vertical metal pillars and the magnetoelectric dipole antenna are superimposed to increase the beam width of the antenna E surface. At 23.5 to 34 GHz, the 3dB beam width is more than 100°, which covers the 5G millimeter wave (24.25-27.5 GHz) frequency band and can be directly applied to linear phased arrays.

[0019] 3. Compared with the existing millimeter wave magnetoelectric dipole antenna, the antenna unit of the present invention has a lower profile. The height of the dielectric substrate is 0.12λ, where λ is the wavelength of the center frequency of 28 GHz. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure is an overall view of a millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna in an embodiment of the present invention.

[0021] Figure 2 The figure is a side view of a millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna in an embodiment of the present invention.

[0022] Figure 3 The figure is a top view of a millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna in an embodiment of the present invention.

[0023] Figure 4 It is a bottom view of a millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna in an embodiment of the present invention.

[0024] Figure 5 This is a curve chart of S-parameter simulation results of a millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna in an embodiment of the present invention.

[0025] Figure 6 It is a schematic diagram of gain simulation results of a millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna in an embodiment of the present invention.

[0026] Figure 7It is a schematic diagram of the radiation pattern simulation results of a millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna at 28 GHz in an embodiment of the present invention.

[0027] Figure 8 It is a schematic diagram of the radiation pattern simulation results of a millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna at 31 GHz in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0029] Example:

[0030] A millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown, it includes four square metal patches 1, a differential coaxial feeding structure, four groups of metal vias 4, a dielectric substrate 5, a metal floor 7 and a vertical metal fence; the differential coaxial feeding structure includes a cross-shaped metal patch 2 and four feeding coaxial lines located under the metal floor 7;

[0031] Four square metal patches 1 are arranged on the upper layer of the dielectric substrate 5 and are bonded to the upper surface of the dielectric substrate 5; the metal floor 7 is arranged on the lower layer of the dielectric substrate 5 and is bonded to the lower surface of the dielectric substrate 5; the cross-shaped metal patch 2 is arranged in the middle of the four square metal patches 1; the outer conductors 8 of the four feeding coaxial lines are all connected to the metal floor 7, and the inner conductors 3 of the four feeding coaxial lines extend into the dielectric substrate 5 and are respectively connected to one end of the cross-shaped metal patch 2; four groups of metal vias are arranged in the dielectric substrate 5, and each group of metal vias 4 is respectively connected to the edge of a square metal patch 1 and the metal floor 7; the vertical metal fence is located in the dielectric substrate 5.

[0032] In this embodiment, the material of the dielectric substrate 5 is Rogers 5880, which has a relative dielectric constant of 2.2 and a loss tangent of 0.0009.

[0033] In this embodiment, the thickness of the dielectric substrate 5 is 1.2-1.5 mm.

[0034] The four square metal patches 1 are arranged in a 2×2 pattern in the center of the upper layer of the dielectric substrate 5 .

[0035] Each group of metal vias 4 includes three cylindrical metal vias 4 , and the three cylindrical metal vias 4 are located at the inner corners of the square metal patch 1 connected thereto.

[0036] The four square metal patches 1 form two pairs of electric dipoles respectively, and the four groups of metal vias 4 form two pairs of magnetic dipoles according to the corresponding square metal patches 1, and finally form two pairs of magneto-electric dipoles, which are called magneto-electric dipole antennas.

[0037] The cross-shaped metal patch 2 is a cross-shaped metal feeding patch structure. 0° and 90° dual-polarization differential feeding is realized on the cross-shaped metal patch 2 through four feeding coaxial lines. Energy is transmitted to two pairs of magnetoelectric dipoles through coupled feeding, which has broadband characteristics.

[0038] The vertical metal fence includes a plurality of vertical fence metal posts 6, which surround two pairs of magneto-electric dipoles. By adding a vertical metal fence around the magneto-electric dipole antenna, a vertical current is introduced, and the beams of the vertical fence metal posts 6 and the magneto-electric dipole antenna are superimposed, which has the characteristics of a wide beam.

[0039] The height of the vertical fence metal posts 6 is flush with the thickness of the dielectric substrate 5 .

[0040] After adjusting the size parameters of each part of the millimeter wave differentially fed dual-polarized wide beam magneto-electric dipole antenna of this embodiment, the millimeter wave differentially fed dual-polarized wide beam magneto-electric dipole antenna of this embodiment is verified and simulated by HFSS software. The overall size of the antenna is 9*9*1.2mm. 3 .like Figure 5 As shown in FIG. 1 , the curve of the S parameter simulation results of the antenna in the frequency range of 20-34 GHz is given; from Figure 5 It can be seen from the figure that in the 22-34 GHz frequency band, S dd11 or S dd22 ≤-10dB, S dd21 ≤-40dB, relative bandwidth is 42.875%. Figure 6 The gain simulation curve in the broadside direction is given in Figure 1. It can be seen that the gain tends to decrease from 22 GHz to 31.5 GHz. When the gain decreases, the beam width of the antenna increases and reaches the maximum at 31.5 GHz. Figure 7 , Figure 8 As shown, the radiation patterns of the antenna at 28 GHz and 31 GHz are given, and it can be seen from the figure that the antenna has a wide beam end-fire performance on the E plane. The simulation results show that the millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna of the present invention has low profile, broadband, wide beam, good polarization diversity capability, low cross-polarization, and can meet the requirements of application in the 5G millimeter wave (24.25-27.5 GHz) frequency band.

[0041] The above-described embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Therefore, all changes made according to the shape and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna, characterized in that: It comprises four square metal patches (1), a differential coaxial feeding structure, four groups of metal vias (4), a dielectric substrate (5), a metal floor (7) and a vertical metal fence; the differential coaxial feeding structure comprises a cross-shaped metal patch (2) and four feeding coaxial lines located under the metal floor (7); Four square metal patches (1) are arranged on the upper layer of the dielectric substrate (5) and are bonded to the upper surface of the dielectric substrate (5); a metal floor (7) is arranged on the lower layer of the dielectric substrate (5) and is bonded to the lower surface of the dielectric substrate (5); a cross-shaped metal patch (2) is arranged in the middle of the four square metal patches (1); the outer conductors (8) of the four feeding coaxial lines are all connected to the metal floor (7); the inner conductors (3) of the four feeding coaxial lines extend into the dielectric substrate (5) and are respectively connected to one end of the cross-shaped metal patch (2); four groups of metal vias are arranged in the dielectric substrate (5), and each group of metal vias (4) is respectively connected to the end of a square metal patch (1). The edge is connected to the metal floor (7); the vertical metal fence is located in the dielectric substrate (5); each group of metal vias (4) includes three cylindrical metal vias (4), and the three cylindrical metal vias (4) are located at the inner corners of the square metal patch (1) connected thereto; the vertical metal fence includes a plurality of vertical fence metal posts (6) surrounding two pairs of magneto-electric dipoles, and by adding a vertical metal fence around the magneto-electric dipole antenna, a vertical current is introduced, and the beams of the vertical fence metal posts (6) and the magneto-electric dipole antenna are superimposed; the four square metal patches (1) are arranged in a 2×2 pattern in the center of the upper layer of the dielectric substrate (5).

2. A millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna according to claim 1, characterized in that: The material of the dielectric substrate (5) is Rogers 5880.

3. The millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna according to claim 1, characterized in that: The thickness of the dielectric substrate (5) is 1.2-1.5 mm.

4. The millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna according to claim 1, characterized in that: The four square metal patches (1) respectively form two pairs of electric dipoles, and the four groups of metal vias (4) respectively form two pairs of magnetic dipoles according to the corresponding square metal patches (1), and finally form two pairs of magneto-electric dipoles, which are called magneto-electric dipole antennas.

5. A millimeter-wave differentially fed dual-polarized wide-beam magneto-electric dipole antenna according to claim 4, characterized in that: The cross-shaped metal patch (2) is a cross-shaped metal feeding patch structure. 0° and 90° dual-polarization differential feeding is realized on the cross-shaped metal patch (2) through four feeding coaxial lines, and energy is transmitted to two pairs of magnetoelectric dipoles through coupled feeding.

6. A millimeter wave differentially fed dual-polarized wide beam magneto-electric dipole antenna according to any one of claims 1 to 5, characterized in that: The height of the vertical fence metal posts (6) is flush with the thickness of the dielectric substrate (5).

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