Low-profile broadband wide-angle scanning magnetoelectric dipole antenna array

Abstract

The invention discloses a low-profile broadband wide-angle scanning magnetoelectric dipole antenna array which is formed by arranging single antenna units in an N * N mode, each antenna unit is composed of a radiation patch layer and a feed structure, the radiation patch layer is arranged on a dielectric substrate, a patch part comprises a parasitic branch knot, an electric dipole patch and a metal patch, the parasitic branch knot is arranged on the dielectric substrate, and the metal patch is arranged on the dielectric substrate. The two metal patches are located on the upper side and the lower side of the two electric dipole patches, each metal patch is connected with two parasitic branches, and the parasitic branches are located at the left end and the right end of the metal patch; the metal patch is connected with the upper part of the metal grounding through hole; the electric dipole patch is connected with the upper part of the magnetic dipole through hole; the feed structure is composed of a coupling feed patch and a feed network, the coupling feed patch is printed on the upper surface of the uppermost layer of dielectric substrate and connected with the upper portion of the coaxial feed through hole, and the feed network is printed on the upper surface of the seventh layer of dielectric substrate and connected with the lower portion of the coaxial feed through hole. The antenna array provided by the invention has the property of wide-band wide-angle scanning.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a low-profile, wide-bandwidth, and angular scanning magneto-electric dipole antenna array. Background Art

[0002] Microstrip patch antennas have the advantages of simple structure, easy processing, and low profile. This type of antenna has a compact structure and is easy to integrate with the back-end RF module. It has great advantages in large array design, so it is often used to design planar phased array antennas. Due to its inherent characteristics, the magnetoelectric dipole antenna has a wide bandwidth and beam width. The traditional magnetoelectric dipole antenna uses an air layer as a medium, so its profile height is too high, which is not conducive to processing and forming an array. The microstrip magnetoelectric dipole antenna overcomes the problem of high antenna profile height, but due to its traditional resonant working principle, the working bandwidth of the microstrip antenna is relatively narrow and the beam width is also narrow. In terms of the E-plane and H-plane scanning width, based on the microstrip magnetoelectric dipole radiation, the present invention introduces JVE and MPE type radiation sources and a method of loading parasitic branches to change the problem of its own narrow radiation width, broaden its beam scanning range on the E-plane and H-plane, and obtain a low-profile, wide-bandwidth angle scanning magnetoelectric dipole antenna.

[0003] The electric dipole is also called an electric oscillator, which can be regarded as a very small current element cut off from a high-frequency current with uniform charge distribution. Assume that the length of the wire is l, the radius is a, and the wavelength of the current corresponding to the frequency is λ. When a<<l<<λ, the current on this current element can be considered to be of equal amplitude and direction. The electric dipole is placed at the origin of the coordinate system along the z-axis, and its radiation pattern in the far field can be calculated by the Maxwell equations. Its radiation pattern on the E plane is an 8-shaped pattern, and its radiation pattern on the H plane is a circle.

[0004] Magnetic dipoles do not exist in nature. They are a kind of imaginary model. A very small circular ring carrying current is used as a model to replace the magnetic dipole for principle analysis. The current loop is simulated at the coordinate center, the radius of the circular ring is set to a, and the distance from the field point to the origin is r, and a<<r. It is assumed that the current distribution at each point on the circular ring is the same. Its E-plane directional diagram is circular, and its H-plane directional diagram is 8-shaped.

[0005] Beam widening technology: The following is an analysis of the detailed mechanism of metal through-hole beam widening, and first discusses the basic carrier antenna. Large planar phased arrays have a large ground plane, which can be regarded as an electric wall or a magnetic wall. Most antenna forms use electric walls as the floor. A small number of antennas, such as introducing artificial magnetic conductors to reduce the cross-sectional height of the antenna, will introduce magnetic walls as the floor. Since the magnetic electric dipole ground proposed in the present invention is an electric wall, only this case is discussed. The radiation structure of the carrier antenna with the electric wall as the floor can be equivalent to a combination of current J and magnetic current M. Further according to their polarization, it can be divided into parallel to the ground and perpendicular to the ground. Therefore, there are four types of carrier antennas based on the electric wall: 1) current parallel to the electric wall (JpE); 2) current perpendicular to the electric wall (JvE); 3) magnetic current parallel to the electric wall (MpE); 4) magnetic current perpendicular to the electric wall (MvE). The four basic types are shown in the figure. The ground is located on the plane of z=0, and the source below the ground is given according to the mirror theory. Considering the source in the figure as an infinitesimal current source, the far-field directional patterns of the four types of antennas can be expressed as:

[0006] 1) JpE: F(θ) = sin(kHcosθ)

[0007] 2)JvE:F(θ)=cos(kHcosθ)sin(θ)

[0008] 3) MpE: F(θ) = cos(kHcosθ)

[0009] 4)MvE: F(θ)=sin(kHcosθ)sin(θ)

[0010] Where k is the wave number, and H is the distance between the source and the electric wall. Among them, the MvE type antenna can neither cover the end-fire direction nor the side-fire direction. JvE can cover the end-fire direction but cannot cover the side-fire direction, and JpE type can cover the side-fire but cannot cover the end-fire direction. Only the MpE type antenna can cover both the end-fire direction and the side-fire direction. Therefore, the addition of metal vias in this paper generates a current perpendicular to the floor, further introducing a JvE type radiation source. In addition, the circular current generated by the metal vias on both sides also further introduces an MpE type radiation source, thereby widening the radiation width of the E and H planes. In addition, in order to further expand the width of the H plane, the present invention introduces parasitic branches at the metal patch on the upper surface of the metal grounding through hole, and radiates outward by coupling feeding with the radiation patch. Since its phase lags behind the radiation patch, it is similar to the director in the Yagi antenna, guiding the antenna beam width backwards and expanding the H plane beam width. Summary of the invention

[0011] The object of the present invention is to provide a low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array.

[0012] The technical solution to achieve the purpose of the present invention is: a low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array, which is composed of single antenna units arranged in an N*N manner, including:

[0013] Dielectric substrate structure: It consists of seven layers of dielectric substrates, on which a through-hole structure is arranged, including metal grounding through-holes and magnetic dipole through-holes penetrating all seven layers of dielectric substrates, coaxial feeding through-holes penetrating the first six layers of dielectric substrates, and isolation holes penetrating only the seventh layer of dielectric substrates;

[0014] A single antenna unit consists of a radiation patch layer and a feeding structure, wherein the radiation patch layer is arranged on a dielectric substrate, and the patch part includes a parasitic branch, an electric dipole patch and a metal patch, wherein two metal patches are located on the upper and lower sides of the two electric dipole patches, and each metal patch is connected to two parasitic branches, which are located at the left and right ends of the metal patch; the metal patch is connected to the top of the metal grounding through hole; the electric dipole patch is connected to the top of the magnetic dipole through hole;

[0015] The feeding structure consists of a coupled feeding patch and a feeding network, wherein the coupled feeding patch is printed on the upper surface of the uppermost dielectric substrate and connected to the top of the coaxial feeding through hole, and the feeding network is printed on the upper surface of the seventh dielectric substrate and connected to the bottom of the coaxial feeding through hole.

[0016] Furthermore, JvE and MpE type radiation sources are introduced through metal grounding vias to broaden the E-plane radiation width of the antenna unit.

[0017] Furthermore, the parasitic branches are rectangular in shape.

[0018] Furthermore, one side of the electric dipole patch is in a rectangular shape, and the other side of the patch is in a U-shaped structure.

[0019] Furthermore, two magnetic dipole through holes are symmetrically connected on the U-shaped electric dipole patch, and three magnetic dipole through holes are connected on the rectangular electric dipole patch.

[0020] Furthermore, the metal grounding vias are symmetrically distributed at equal intervals on the upper and lower sides of the electric dipole patch, and the radius of the metal grounding vias is different from that of the magnetic dipole vias and the coaxial feeding vias.

[0021] Furthermore, the radius of the metal grounding via is 0.2 mm, the radius of the magnetic dipole via is 0.15 mm, and the radius of the coaxial feed via is 0.25 mm.

[0022] Furthermore, the metal patch continuously covers the upper surface of the metal grounding through hole.

[0023] Furthermore, the number and radius of the metal ground vias are related to the impedance matching and gain of the antenna unit.

[0024] Furthermore, the feed source feeds the coupled feed patch through the coaxial feed via, and the coupled feed patch feeds the electric dipole patch and the magnetic dipole via by coupling feeding to enable them to radiate outward. On this basis, the electric dipole patch feeds the metal patch and parasitic branches by coupling feeding to widen the radiation beam width.

[0025] Compared with the prior art, the present invention has the following significant advantages: 1) Metal through-hole structures are added on both sides of the electric dipole and parasitic branch structures are added on the metal patches on both sides of the electric dipole, wherein the newly added metal through-holes have the effect of greatly expanding the E-plane radiation width and slightly expanding the H-plane beam width, and the parasitic branch structures have the effect of expanding the H-plane beam width, ultimately making the antenna have the properties of wide-angle scanning of the E-plane and H-plane. 2) The overall antenna adopts a microstrip structured magnetoelectric dipole antenna, which reduces the antenna profile height. 3) The antenna units can be arranged in an N*N array to improve the antenna gain and have a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a three-dimensional structural decomposition diagram of the present invention.

[0027] Figure 2 1 is a top view of the upper surface and structural parameters of the antenna unit of the present invention.

[0028] Figure 3 The upper surface current distribution of the antenna unit of the present invention.

[0029] Figure 4 This is the effect of the diameter of the metal grounding through hole of the antenna unit of the present invention on the impedance bandwidth.

[0030] Figure 5 This is the effect of the diameter of the metal grounding through hole of the antenna unit of the present invention on the E-plane beam width.

[0031] Figure 6 This is the effect of the number of metal grounding vias in the antenna unit of the present invention on the impedance bandwidth.

[0032] Figure 7 This is the effect of the number of metal grounding vias in the antenna unit of the present invention on the E-plane beam width.

[0033] Figure 8 This is the effect of the parasitic branch length of the antenna unit of the present invention on the impedance bandwidth.

[0034] Fig. 9 This is the effect of the parasitic branch length of the antenna unit of the present invention on the H-plane beam width.

[0035] Fig.10 This is the effect of the parasitic branch width of the antenna unit on the impedance bandwidth of the present invention.

[0036] Fig.11This is the effect of the parasitic branch length of the antenna unit of the present invention on the H-plane beam width.

[0037] Fig.12 This is a diagram of the four-channel feeding S11 of the 2×2 antenna array of the present invention.

[0038] Fig.13 The beam patterns of the 2×2 antenna array of the present invention in the E-plane and H-plane. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0040] The low-profile, wide-bandwidth, and angular scanning magnetoelectric dipole antenna array of the present invention can be composed of single antenna units arranged in an N*N manner. It includes:

[0041] The dielectric substrate structure is composed of seven layers of dielectric substrates, on which a through-hole structure is arranged, including: a metal grounding through-hole (3) and a magnetic dipole through-hole (14) penetrating all seven layers of dielectric substrates, a coaxial feeding through-hole (15) penetrating the first six layers of dielectric substrates, and an isolation hole (11) penetrating only the seventh layer of dielectric substrates.

[0042] A single antenna unit is composed of a radiation patch layer (1) and a feeding structure. The radiation patch layer (1) is arranged on a dielectric substrate (2). The patch part includes a parasitic branch (12), an electric dipole patch (13) and a metal patch (16). Two metal patches (16) are located on the upper and lower sides of the two electric dipole patches (13). Each metal patch (16) is connected to two parasitic branches (12). The parasitic branches (12) are located at the left and right ends of the metal patch (16). The metal patch (16) is connected to the top of the metal grounding through hole (3). The added metal grounding through hole (3) introduces JvE and MpE type radiation sources, which greatly widens the E-plane radiation width of the antenna unit. The electric dipole patch (13) is connected to the top of the magnetic dipole through hole (14). The parasitic branch (12) is a patch part led out from the metal patch (16). The parasitic branch is similar to the director in the Yagi antenna. The current phase lags behind the electric dipole patch. The electric dipole patch is coupled to feed the guided beam to further widen the H-plane radiation width. The feeding structure is composed of a coupled feeding patch (17) and a feeding network (9). The coupled feeding patch (17) is printed on the upper surface of the uppermost dielectric substrate (2) and is connected to the top of the coaxial feeding through hole (15). The feeding network (9) is printed on the upper surface of the seventh dielectric substrate and is connected to the bottom of the coaxial feeding through hole (15).

[0043] Furthermore, one patch on one side of the electric dipole patch (13) is in a rectangular shape, and the other patch on the other side is in a U-shaped structure. The upper surfaces of the plurality of magnetic dipole through holes (14) are respectively connected to the two electric dipole patches (13), wherein the U-shaped electric dipole patch has two magnetic dipole through holes connected symmetrically, and the rectangular electric dipole patch has three magnetic dipole through holes connected.

[0044] Furthermore, the metal grounding through holes (3) are symmetrically distributed at equal intervals on the upper and lower sides of the electric dipole patch (13), and their radius is different from that of the magnetic dipole through hole (14) and the coaxial feeding through hole (15).

[0045] Furthermore, the metal patch (16) continuously covers the upper surface of the metal grounding through hole (3), which ensures the continuity of the through holes on both sides. A rectangular parasitic branch (12) is connected to both ends of a metal patch (16), and an antenna unit has four parasitic branches (12).

[0046] In a low-profile, wide-bandwidth, angular scanning magnetoelectric dipole antenna array, a feed source feeds a coupled feed patch (17) through a coaxial feed through hole (15), and the coupled feed patch (17) feeds an electric dipole patch (13) and a magnetic dipole through hole (14) through coupled feeding to enable them to radiate outwards. On this basis, the electric dipole patch (13) feeds a metal patch (16) and a parasitic branch (12) through coupled feeding to widen the radiation beam width.

[0047] Furthermore, the number and radius of the metal grounding vias (3) are related to the impedance matching and gain of the antenna unit.

[0048] In summary, the present invention adopts a microstrip antenna structure to reduce the cross-sectional height of the traditional magneto-electric dipole antenna. By adding a metal grounding through hole in the radiation patch layer to form a current perpendicular to the floor, JvE and MpE type radiation sources are introduced to greatly widen the E-plane radiation width and slightly widen the H-plane radiation width. Parasitic branches are introduced at the metal patch above the metal through hole in the radiation patch layer, which is similar to the director in the Yagi antenna. The current phase lags behind the electric dipole patch. The electric dipole patch is coupled to feed the guided beam to radiate backward to further widen the H-plane radiation width.

[0049] Example

[0050] In order to verify the effectiveness of the scheme of the present invention, the following experiment was carried out.

[0051] like Figure 1As shown, a low-profile, wide-bandwidth, angular scanning magneto-electric dipole 2×2 antenna array, a single antenna unit includes a 7-layer dielectric substrate structure, wherein the metal through-hole structure includes 22 metal grounding through-holes 3 penetrating the 7-layer dielectric substrate structure, a coaxial feeding through-hole 15 penetrating the first 6 layers of the dielectric substrate structure, and an isolation hole 11 penetrating only the bottom dielectric substrate. The top dielectric substrate structure is printed with a radiation patch layer 1, which includes two different electric dipole patches 13, 5 magnetic dipole through-holes 14, 2 metal patches, and 4 parasitic branches 12. The feeding structure includes a feeding coupling patch 17 and a feeding network 9.

[0052] The electric dipole patch 13 and the magnetic dipole through hole 14 on the radiation patch layer 1 introduce a resonance point at low frequency and high frequency respectively, which broadens the impedance bandwidth of the antenna unit. And by adding metal grounding through holes 3 on both sides of the electric dipole patch 13, the E-plane beam width is greatly broadened, and the H-plane beam width is slightly broadened. Parasitic branches are added on both sides of the electric dipole patch 13 to broaden the H-plane beam width.

[0053] like Figure 2 As shown, by printing the metal patch 16 in the area where the metal grounding via 3 is connected to the upper radiation patch layer 1, the continuity of the metal grounding via can be ensured.

[0054] like Figure 3 As shown, the current phase of the parasitic branch 12 lags behind the current phase of the electric dipole patch 13, which can guide the beam to radiate backward.

[0055] like Figure 4 , 5 As shown, the impedance matching and gain of the 2×2 antenna array can be affected by adjusting the radius of the metal ground via 3 .

[0056] like Figure 6 , 7 As shown, the impedance matching and gain of the 2×2 antenna array can be affected by adjusting the number of metal ground vias 3 .

[0057] like Figure 8 , 9 As shown, the impedance matching and gain of the 2×2 antenna array can be affected by adjusting the length of the parasitic stub.

[0058] like Fig.10 , 11 As shown, the impedance matching and gain of the 2×2 antenna array can be affected by adjusting the width of the parasitic branch 12 .

[0059] Some parameters of each unit of the upper surface radiation layer 1 are shown in Table 1 below:

[0060] Table 1

[0061]

[0062] In the above Table 1, Parameter is the parameter name given in the radiation unit, and Units (mm) represents the specific value of each parameter and is in millimeters. Among them, I1 is the length of the U-shaped electric dipole patch 13, I2 is the width of the U-shaped part of the U-shaped electric dipole patch 13, I3 is the width from the center of the magnetic dipole through hole 14 on the U-shaped electric dipole patch 13 to the edge of the U-shaped part of the U-shaped electric dipole patch 13, I4 is the width of the narrow side of the coupling feed patch 17, I5 is the width of the wide side of the coupling feed patch 17, I6 is the length of the other wide side of the coupling feed patch 17, I9 is ​​the width of the parasitic patch branch, and I1 0 is the length of the parasitic patch branch, dx and dy are the length and width of a single antenna unit respectively, w1 is the width of the U-shaped electric dipole patch 13, w2 is the length of the narrow side part of the coupling feed patch 17, w3 is the length of the wide side part of the coupling feed patch 17, w4 is the width of the other wide side part of the coupling feed patch 17, w5 is the width of the rectangular electric dipole patch 13, and d1 is the spacing width from the U-shaped electric dipole 13 to the rectangular metal patch 16.

[0063] like Fig.12 As shown, the 2×2 antenna array is simulated by the simulation software HFSS to obtain the S11 simulation diagram of its four feeding channels.

[0064] like Fig.13 As shown, the 2×2 antenna array is simulated by the simulation software HFSS to obtain the simulation diagrams of its E-plane and H-plane.

[0065] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0066] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array, characterized in that: It consists of single antenna units arranged in N*N format, including: The dielectric substrate structure is composed of seven layers of dielectric substrates, on which a through-hole structure is arranged, including a metal grounding through-hole (3) and a magnetic dipole through-hole (14) penetrating all seven layers of dielectric substrates, a coaxial feeding through-hole (15) penetrating the first six layers of dielectric substrates, and an isolation hole (11) penetrating only the seventh layer of dielectric substrate; A single antenna unit is composed of a radiation patch layer (1) and a feeding structure, wherein the radiation patch layer (1) is arranged on a dielectric substrate (2), the patch part comprises a parasitic branch (12), an electric dipole patch (13) and a metal patch (16), two metal patches (16) are located on the upper and lower sides of the two electric dipole patches (13), each metal patch (16) is connected to two parasitic branches (12), and the parasitic branches (12) are located at the left and right ends of the metal patch (16); the metal patch (16) is connected to the top of the metal grounding through hole (3); the electric dipole patch (13) is connected to the top of the magnetic dipole through hole (14); The feeding structure consists of a coupling feeding patch (17) and a feeding network (9), wherein the coupling feeding patch (17) is printed on the upper surface of the uppermost dielectric substrate (2) and connected to the upper part of the coaxial feeding through hole (15), and the feeding network (9) is printed on the upper surface of the seventh dielectric substrate and connected to the lower part of the coaxial feeding through hole (15).

2. The low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array according to claim 1, characterized in that: JvE and MpE type radiation sources are introduced through the metal grounding through hole (3) to broaden the E-plane radiation width of the antenna unit.

3. The low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array according to claim 1, characterized in that: The parasitic branch (12) is rectangular in shape.

4. The low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array according to claim 1, characterized in that: The patch on one side of the electric dipole patch (13) is in a rectangular shape, and the patch on the other side is in a U-shaped structure.

5. The low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array according to claim 4, characterized in that: There are two magnetic dipole through holes connected symmetrically on the U-shaped electric dipole patch, and there are three magnetic dipole through holes connected on the rectangular electric dipole patch.

6. The low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array according to claim 1, characterized in that: The metal grounding through holes (3) are symmetrically distributed at equal intervals on the upper and lower sides of the electric dipole patch (13), and the radius of the metal grounding through holes (3) is different from that of the magnetic dipole through holes (14) and the coaxial feeding through holes (15).

7. The low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array according to claim 6, characterized in that: The radius of the metal grounding through hole (3) is 0.2 mm, the radius of the magnetic dipole through hole (14) is 0.15 mm, and the radius of the coaxial feeding through hole (15) is 0.25 mm.

8. The low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array according to claim 1, characterized in that: The metal patch (16) continuously covers the upper surface of the metal grounding through hole (3).

9. The low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array according to claim 1, characterized in that: The number and radius of the metal grounding vias (3) are related to the impedance matching and gain of the antenna unit.

10. The low-profile, wide-bandwidth, angular scanning magneto-electric dipole antenna array according to claim 1, characterized in that: The feed source feeds the coupled feed patch (17) through the coaxial feed through hole (15), and the coupled feed patch (17) feeds the electric dipole patch (13) and the magnetic dipole through hole (14) through coupled feeding so that they radiate outwards. On this basis, the electric dipole patch (13) feeds the metal patch (16) and the parasitic branch (12) through coupled feeding so as to widen the radiation beam width.

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