A dual-polarized phased array antenna that simultaneously improves homopolar and heteropolar coupling

Abstract

The application discloses a dual-polarized phased array antenna capable of simultaneously improving homopolar and heteropolar coupling, comprising a plurality of antenna units distributed in two polarization directions, adjacent antenna units are in L-shaped positional relationship, and a cross-shaped structure is formed by four adjacent antenna units; each antenna unit comprises a dipole antenna, a decoupling surface and a metal cavity, the decoupling surface is suspended above the dipole antenna, and the dipole antenna is located in the metal cavity; the dipole antenna comprises a first dielectric substrate, a second dielectric substrate and a third dielectric substrate which are sequentially stacked, and a first dipole arm, a first traveling wave guide, a third dipole arm, a metal conductor strip, a second dipole arm, a second traveling wave guide, a first metal surface, a second metal surface and a ground coplanar waveguide transition substrate integrated coaxial line. The application effectively improves the coupling between homopolar and heteropolar dipoles, has an impedance bandwidth of 31.9%, the isolation degree is better than 20 dB within the working bandwidth, and the beam scanning angle range reaches ± 40°.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of antennas, and particularly relates to a dual-polarized phased array antenna capable of simultaneously improving homopolar and heteropolar coupling. BACKGROUND

[0002] With the rapid development of modern communication, the demand of users for wireless communication is increasing, and thus higher requirements are put forward for wireless communication services. The fifth generation (5G) wireless communication technology with the characteristics of high speed, low latency and large capacity emerges as the times require. Compared with the low frequency band below 6 GHz, the millimeter wave frequency band with rich spectrum resources can provide higher data throughput and lower delay. However, the millimeter wave frequency is higher, which causes the increase of path loss, has the characteristics of easy attenuation and short transmission distance. The phased array technology can adjust the phase and amplitude of each unit of the array antenna to control the beam, maximize the energy of the main lobe radiation, and reduce the energy of the side lobe radiation. By using the characteristics of the phased array technology, directional transmission can be realized, the transmission distance is increased, and the characteristics of high path loss of the millimeter wave are overcome. Therefore, the design of the wideband phased array antenna in the millimeter wave frequency band is of great significance to the millimeter wave 5G communication.

[0003] The dual-polarized antenna can simultaneously transmit and receive two orthogonal polarized signals, which is equivalent to transmitting twice the amount of data in the same frequency spectrum. This technology is particularly important in the MIMO (Multiple Input Multiple Output) system, which can significantly improve the data transmission rate and system capacity, and has important application value in the phased array antenna in the millimeter wave band. However, the dual-polarized antenna array also has the problem of diversified polarization mutual coupling, including homopolar mutual coupling and heteropolar mutual coupling of different units. In terms of circuit performance, mutual coupling leads to matching deterioration and isolation reduction. In terms of radiation performance, mutual coupling leads to antenna gain reduction, efficiency reduction and pattern distortion. In addition, the coupling between different polarizations also affects the performance of polarization diversity in the MIMO system. Therefore, for the dual-polarized phased array antenna, it is of great significance to study a structure capable of realizing wideband decoupling of the dual-polarized phased array antenna. SUMMARY

[0004] The purpose of the application is to solve the problem of various types of coupling of the dual-polarized phased array antenna, and a dual-polarized phased array antenna capable of simultaneously improving homopolar and heteropolar coupling is proposed. The decoupling surface structure is suspended above the dipole antenna at a position of about 0.2 times the wavelength, a reverse coupling path is introduced between the dipole antennas, and a metal cavity is placed between the dipole antennas to block the spatial wave coupling of the dipole antennas. The two structures realize wideband decoupling of the antenna, and the antenna maintains good impedance matching and has a wideband characteristic, with a maximum beam scanning angle range of ±40°.

[0005] The application is realized by the following technical scheme: a dual-polarized phased array antenna for simultaneously improving homopolar and heteropolar coupling, working in a millimeter wave frequency band, comprising 2 n periodically distributed antenna units, n≥2, adjacent antenna units are in an L-shaped positional relationship, and a cross-shaped structure is formed by four adjacent antenna units.

[0006] Each antenna unit comprises a dipole antenna, a decoupling surface, and a metal cavity, wherein the decoupling surface is suspended above the dipole antenna, and the dipole antenna is located in the metal cavity; the metal cavities of adjacent antenna units share the same cavity side wall.

[0007] The dipole antenna comprises a first dielectric substrate, a second dielectric substrate, a third dielectric substrate, a first dipole arm, a first traveling wave antenna, a third dipole arm, a metal conductor strip, a second dipole arm, a second traveling wave antenna, a first metal surface, a second metal surface, and a ground coplanar waveguide conversion substrate integrated coaxial line arranged in sequence.

[0008] The first dielectric substrate is located below the decoupling surface and is arranged vertically to the decoupling surface.

[0009] The front surface of the first dielectric substrate is provided with the first metal surface, the first dipole arm, the first traveling wave antenna, and the ground coplanar waveguide conversion substrate integrated coaxial line; the first metal surface serves as a reflection plate of the first dipole; one end of the first dipole arm close to the decoupling surface is terminated at the first metal surface; the other end of the first dipole arm is suspended, and two first traveling wave antennas are arranged at the suspended end side; the ground coplanar waveguide conversion substrate integrated coaxial line is arranged at the end of the first metal surface away from the decoupling surface.

[0010] The second dielectric substrate is located at the back surface of the first dielectric substrate and is used to bond the first dielectric substrate and the third dielectric substrate.

[0011] The third dielectric substrate is located at the back surface of the second dielectric substrate.

[0012] The back surface of the third dielectric substrate is provided with the second metal surface, the second dipole arm, and the second traveling wave antenna; the second metal surface serves as a reflection plate of the second dipole; one end of the second dipole arm close to the decoupling surface is terminated at the second metal surface; the other end of the second dipole arm is suspended, and two second traveling wave antennas are arranged at the suspended end side.

[0013] The metal conductor strip is located between the third dielectric substrate and the second dielectric substrate; one end of the third dipole arm close to the decoupling surface is terminated at the metal conductor strip, and the other end of the third dipole arm is suspended.

[0014] The decoupling surface comprises a fourth dielectric substrate and a third metal surface located on the upper surface of the fourth dielectric substrate.

[0015] The third metal surface comprises metal patches in a 2*3 matrix distribution, and there is a spacing between adjacent metal patches.

[0016] The feeding element is composed of a ground coplanar waveguide-substrate integrated coaxial line and a metal conducting strip; two sides of the metal conducting strip are provided with a plurality of periodically distributed first metallized through holes; the first metallized through holes penetrate the first dielectric substrate, the second dielectric substrate and the third dielectric substrate, and are used for connecting the first metal surface and the second metal surface; the bottom end of the metal conducting strip is connected with the ground coplanar waveguide-substrate integrated coaxial line through a second metallized blind hole; the second metallized blind hole penetrates the first dielectric substrate.

[0017] Preferably, the distance between the decoupling surface and the dipole antenna is 0.2λ0, and λ0 is the wavelength corresponding to the center operating frequency of the antenna unit.

[0018] Preferably, the two first director oscillators have the same length and width and are arranged in parallel, and there is a distance between the two first director oscillators; the first director oscillator close to the first dipole arm has a distance from the first dipole arm; the two second director oscillators have the same length and width and are arranged in parallel, and there is a distance between the two second director oscillators; the second director oscillator close to the second dipole arm has a distance from the second dipole arm.

[0019] Preferably, the first dipole arm and the second dipole arm are oriented in the same direction, and the third dipole arm is oriented in the opposite direction.

[0020] Preferably, the top end of the metal cavity is lower than the suspended end of the first dipole arm.

[0021] Preferably, the distance from the suspended end of the first dipole arm to the end of the first metal surface close to the decoupling surface is less than or equal to λ0 / 4; λ0 is the wavelength corresponding to the center operating frequency of the antenna unit; the distance from the suspended end of the second dipole arm to the end of the second metal surface close to the decoupling surface is less than or equal to λ0 / 4; λ0 is the wavelength corresponding to the center operating frequency of the antenna unit.

[0022] Preferably, the length and width of the first director oscillator and the second director oscillator are equal.

[0023] The present application has the following characteristics:

[0024] (1) The antenna adopts the structure of a metal cavity and a decoupling surface, which greatly improves the coupling of the same-polarization and different-polarization dipole antenna units, and the decoupling structure is small in size and easy to design and process.

[0025] (2) The antenna realizes a high isolation degree of more than 20 dB within the operating frequency band on the basis of maintaining good impedance matching of the antenna.

[0026] (3) Compared with the common millimeter wave dual-polarized phased array antenna, the array has a larger bandwidth (23.7~32.7Ghz) and higher gain, and has good beam scanning performance, and the maximum scanning angle reaches 40°. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a three-dimensional structural schematic diagram of the dual-polarized phased array antenna of the application.

[0028] Figure 2 is a three-dimensional structural schematic diagram of the antenna unit of the application.

[0029] Figure 3 (a) in the figure is a bottom view of the antenna unit.

[0030] Figure 3 (b) in the figure is a side view of the dual-polarized phased array antenna.

[0031] Figure 3 (c) in the figure is a side view of the dual-polarized phased array antenna without a metal cavity.

[0032] Figure 4 is a top view of the dual-polarized phased array antenna of the application.

[0033] Figure 5 is a unit reflection coefficient simulation diagram of the application.

[0034] Figure 6 is an isolation degree simulation diagram between units of the application.

[0035] Figure 7 is a comparison diagram of the isolation degree simulation results of the application and the reference antenna without a metal cavity structure.

[0036] Figure 8 is a comparison diagram of the isolation degree simulation results of the application and the reference antenna without a decoupling surface structure.

[0037] Figure 9 is the active S parameter of the center antenna unit when the E plane beam of the application is scanned.

[0038] Figure 10 is the active S parameter of the center antenna unit when the H plane beam of the application is scanned.

[0039] Figure 11 is the E plane directional beam scanning diagram of the application at 27GHz.

[0040] Figure 12 is the H plane directional beam scanning diagram of the application at 27GHz.

[0041] The diagram is labeled as follows: 1. Dipole antenna; 1-1. First dielectric substrate; 1-2. Second dielectric substrate; 1-3. Third dielectric substrate; 1-4. First dipole arm; 1-5. First director element; 1-6. Third dipole arm; 1-7. Metal conductor strip; 1-8. Second dipole arm; 1-9. Second director element; 1-10. First metal surface; 1-11. Second metal surface; 1-12. Grounded coplanar waveguide to substrate integrated coaxial line; 1-13. First metallized via; 1-14. Second metallized blind via; 2. Decoupling surface; 2-1. Fourth dielectric substrate; 2-2. Third metal surface; 3. Metal cavity. Detailed Implementation

[0042] The present invention will be further analyzed below with reference to specific embodiments.

[0043] like Figure 1 , Figure 4 As shown, a dual-polarized phased array antenna that simultaneously improves co-polarization and hetero-polarization coupling operates in the millimeter-wave band includes 2 n There are 32 periodically distributed antenna elements, n≥2, with adjacent antenna elements in an L-shaped positional relationship, and four adjacent antenna elements forming a cross-shaped structure; this embodiment uses 32 antenna elements arranged in a cross pattern, with 16 antenna elements in both the horizontal and vertical directions. The horizontal direction is denoted as the X-axis, the vertical direction as the Y-axis, and the direction perpendicular to the XOY plane as the Z-axis.

[0044] like Figure 2 , Figure 3 (a) Figure 3 (b) Figure 3 As shown in (c), each antenna element includes a dipole antenna 1, a decoupling surface 2, and a metal cavity 3, wherein the decoupling surface 2 is suspended above the dipole antenna 1, and the dipole antenna 1 is located inside the metal cavity 3; the metal cavities 3 of adjacent antenna elements share the same cavity sidewall.

[0045] The distance between the decoupling surface 2 and the dipole antenna 1 is 0.2λ0, where λ0 is the wavelength corresponding to the center operating frequency of the antenna element.

[0046] The dipole antenna 1 includes a first dielectric substrate 1-1, a second dielectric substrate 1-2, a third dielectric substrate 1-3 stacked in sequence, a first dipole arm 1-4, a first director 1-5, a third dipole arm 1-6, a metal conductor 1-7, a second dipole arm 1-8, a second director 1-9, a first metal surface 1-10, a second metal surface 1-11, and a grounded coplanar waveguide-to-substrate integrated coaxial line 1-12.

[0047] The first dielectric substrate 1-1 is located below the decoupling surface 2 and is vertically arranged with the decoupling surface 2; the first dielectric substrate 1-1 is made of Rogers 5880, the dielectric constant is 2.2, the loss tangent is 0.0009, and the thickness is 0.254 mm.

[0048] The front surface of the first dielectric substrate 1-1 is provided with a first metal surface 1-10, a first dipole arm 1-4, a first director 1-5, and a ground coplanar waveguide to substrate integrated coaxial line 1-12; the first metal surface 1-10 serves as a reflection plate of the first dipole; one end of the first dipole arm 1-4 close to the decoupling surface 2 is terminated on the first metal surface 1-10; the other end of the first dipole arm 1-4 is suspended, and the suspended end is provided with the first director 1-5; the first metal surface 1-10 away from the decoupling surface 2 is provided with a gap, and the gap is composed of a first gap and a second gap which are integrally formed, the width of the first gap is smaller than that of the second gap, and the ground coplanar waveguide to substrate integrated coaxial line 1-12 is arranged in the first gap; there is a gap between the ground coplanar waveguide to substrate integrated coaxial line 1-12 and the first metal surface 1-10.

[0049] The first director 1-5 includes two metal patches with the same length and width and arranged in parallel, and there is a distance between the two metal patches; the first director 1-5 close to the first dipole arm 1-4 has a distance from the first dipole arm 1-4; the second director 1-9 includes two metal patches with the same length and width and arranged in parallel, and there is a distance between the two metal patches; the second director 1-9 close to the second dipole arm 1-8 has a distance from the second dipole arm 1-8; the length Ld of the dipole arm composed of the first dipole arm 1-4, the second dipole arm 1-8, and the third dipole arm 1-6 is 4.35 mm, the width Wd of the dipole arm is 0.7 mm, and the distance Lst between the dipole arm and the reflection plate is 1.8 mm; the distance Ddip between the dipoles of the dipole antenna 1 of the adjacent antenna units in the same polarization direction is 6.3 mm; the length Lyin1 and Lyin2 of the two metal patches of the first director 1-5 are both 2.9 mm, the distance Hyin1 between the first metal patch of the first director 1-5 (i.e., the metal patch close to the first dipole arm 1-4) and the first dipole arm 1-4 is 0.2 mm, and the distance Hyin2 between the two metal patches of the first director 1-5 is 1.1 mm.

[0050] The second dielectric substrate 1-2 is located on the back surface of the first dielectric substrate 1-1 and is used to bond the first dielectric substrate 1-1 and the third dielectric substrate 1-3; the second dielectric substrate 1-2 is made of Roger 450F, the dielectric constant is 3.52, the loss tangent is 0.004, and the thickness is 0.1 mm.

[0051] The third dielectric substrate 1-3 is located on the back of the second dielectric substrate 1-2; the third dielectric substrate 1-3 is Rogers 5880, the dielectric constant is 2.2, the loss tangent is 0.0009, and the thickness is 0.254 mm.

[0052] The back of the third dielectric substrate 1-3 is provided with a second metal surface 1-11, a second dipole arm 1-8, and a second director 1-9; the second metal surface 1-11 is used as a reflection plate of the second dipole; one end of the second dipole arm 1-8 close to the decoupling surface 2 is terminated on the second metal surface 1-11; the other end of the second dipole arm 1-8 is suspended, and a second director 1-9 is arranged on the side of the suspended end.

[0053] The metal strip 1-7 is located between the first dielectric substrate 1-1 and the second dielectric substrate 1-2; one end of the third dipole arm 1-6 close to the decoupling surface 2 is terminated on the metal strip 1-7, and the other end of the third dipole arm 1-6 is suspended.

[0054] The first dipole arm 1-4 and the second dipole arm 1-8 are oriented in the same direction, and the third dipole arm 1-6 is oriented in the opposite direction.

[0055] The decoupling surface 2 includes a fourth dielectric substrate 2-1 and a third metal surface 2-2 located on the upper surface of the fourth dielectric substrate 2-1.

[0056] The third metal surface 2-2 includes rectangular metal patches arranged in a 2x3 matrix, and there is a spacing between adjacent metal patches; the length L of the metal patch is 1 mm, the width is 1 mm, and the spacing between adjacent metal patches is 0.1 mm; the third metal surface 2-2 is directly above the dipole antenna 1, and the array distribution of the rectangular metal patches is the same as the two polarization directions of the dipole antenna 1.

[0057] The feeding element is composed of the ground coplanar waveguide to substrate integrated coaxial line 1-12 and the metal strip 1-7; the metal strip 1-7 is provided with a plurality of periodically distributed first metallized through holes 1-13 on both sides, that is, a plurality of first metallized through holes 1-13 are arranged on both sides of the first and second notches; the first metallized through holes 1-13 penetrate the first dielectric substrate 1-1, the second dielectric substrate 1-2, and the third dielectric substrate 1-3, and are used to connect the first metal surface 1-10 and the second metal surface 1-11; the bottom end of the metal strip 1-7 is connected with the ground coplanar waveguide to substrate integrated coaxial line 1-12 through a second metallized blind hole 1-14; the second metallized blind hole 1-14 penetrates the first dielectric substrate 1-1; the spacing Wout between the two rows of first metallized through holes 1-13 located on both sides of the metal strip 1-7 is 2 mm.

[0058] The upper part of the first dielectric substrate 1-1, the second dielectric substrate 1-2 and the third dielectric substrate 1-3 of the dipole antenna 1 is cut off partially for placing the metal cavity 3; the lower part of the dielectric substrate of adjacent dipole antennas 1 is in contact. The number of the metal cavities 3 is the same as that of the dipole antennas 1. The width Wsub of the upper part of the first dielectric substrate 1-1, the second dielectric substrate 1-2 and the third dielectric substrate 1-3 is 6.3 mm; the height Hcav of the metal cavity 3 is 5.2 mm, and the diagonal length Lcav of the metal cavity 3 is 6.4 mm.

[0059] The dipole antennas 1 of the same polarization are arranged equidistantly.

[0060] The width Wsub of the upper part of the first dielectric substrate 1-1, the second dielectric substrate 1-2 and the third dielectric substrate 1-3 is less than the diagonal length Lcav of the metal cavity 3. There is a gap between the upper part of the dielectric substrate and the metal cavity 3.

[0061] The top end of the metal cavity 3 is lower than the overhanging end of the first dipole arm 1-4.

[0062] The distance from the overhanging end of the first dipole arm 1-4 to the end of the first metal surface 1-10 close to the decoupling surface 2 is less than or equal to λ0 / 4; λ0 is the wavelength corresponding to the center operating frequency of the antenna unit; the distance from the overhanging end of the second dipole arm 1-8 to the end of the second metal surface 1-11 close to the decoupling surface 2 is less than or equal to λ0 / 4; λ0 is the wavelength corresponding to the center operating frequency of the antenna unit.

[0063] The length and width of the first director 1-5 and the second director 1-9 are equal.

[0064] The adjacent antenna units are in L-shaped positional relationship, realizing the characteristics of dual polarization. When one of the antenna units is working, the signal is transmitted from the grounded coplanar waveguide to the dipole antenna 1 through the substrate integrated coaxial line 1-12. Each antenna unit is located in the metal cavity 3, which can block the spatial coupling wave between the antenna units of different polarizations, and can well improve the cross-polarization coupling. A decoupling surface 2 is arranged above the antenna, and each antenna unit has a third metal surface 2-2 with a 2*3 matrix distribution of multiple rectangular metal patches arranged above it. The decoupling surface 2 with the third metal surface 2-2 can generate an opposite coupling wave, the spatial coupling wave of the antenna units of the same polarization is cancelled, and the co-polarization coupling can be well improved.

[0065] Figure 5 The S parameter simulation result diagram of the dual-polarized phased array antenna of the application shows that the -10 dB bandwidth (23.7~32.7Ghz) reaches 31.9%, which indicates that the antenna realizes good impedance matching and has a wideband characteristic.

[0066] Figure 6A simulation result diagram of isolation degrees between adjacent units of the dual-polarized phased array antenna of the application, including E-plane co-polarization, H-plane co-polarization and cross-polarization isolation degrees, is less than -20dB in the working frequency range of 23.7-32.7GHz.

[0067] Figure 7~8 A comparison diagram of isolation degrees between the application and a reference antenna without a metal cavity and a decoupling surface can be seen that, after the antenna is loaded with the metal cavity and the decoupling surface, the E-plane co-polarization and cross-polarization isolation degrees are significantly improved, realizing wideband decoupling, and the maximum isolation degree is improved by 23dB.

[0068] Figure 9~10 Active S parameters of a center antenna unit of the dual-polarized phased array antenna of the application, including different scanning angles of E-plane and H-plane, can be seen that the phased array antenna maintains good active impedance matching when the beam is scanned.

[0069] Figure 11~12 A beam scanning simulation diagram of the dual-polarized phased array antenna of the application at 27GHz, including E-plane scanning and H-plane scanning, can be seen that, in the scanning range of 3dB gain change, the maximum beam pointing of the phased array antenna reaches ±40°, verifying that the antenna has good beam scanning capability.

[0070] The above only describes the preferred embodiments of the application, and does not limit the embodiments of the application. It should be noted that for those skilled in the art, without departing from the principles of the application, a number of improvements and refinements can be made, which should be included in the protection scope of the claims of the application.

Claims

1. A dual-polarized phased array antenna that simultaneously improves homopolar and heteropolar coupling, characterized in that Comprising 2 n periodically distributed antenna units, n≥2, adjacent antenna units are in L-type positional relationship, and a cross-shaped structure is formed by four adjacent antenna units; Each antenna unit comprises a dipole antenna (1), a decoupling surface (2), a metal cavity (3), wherein the decoupling surface (2) is suspended above the dipole antenna (1), and the dipole antenna (1) is located in the metal cavity (3); The dipole antenna (1) comprises a first dielectric substrate (1-1), a second dielectric substrate (1-2), a third dielectric substrate (1-3), a first dipole arm (1-4), a first director (1-5), a third dipole arm (1-6), a metal strap (1-7), a second dipole arm (1-8), a second director (1-9), a first metal surface (1-10), a second metal surface (1-11), and a ground coplanar waveguide to substrate integrated coaxial line (1-12) arranged in sequence.

2. The antenna of claim 1, wherein The distance between the decoupling surface (2) and the dipole antenna (1) is 0.2λ0, and λ0 is the wavelength corresponding to the center operating frequency of the antenna unit.

3. The antenna of claim 1, wherein In the dipole antenna (1), the first dielectric substrate (1-1) is located below the decoupling surface (2) and is arranged vertically to the decoupling surface (2); The front surface of the first dielectric substrate (1-1) is provided with the first metal surface (1-10), the first dipole arm (1-4), the first director (1-5), and the ground coplanar waveguide to substrate integrated coaxial line (1-12); one end of the first dipole arm (1-4) close to the decoupling surface (2) is connected to the first metal surface (1-10); the other end of the first dipole arm (1-4) is suspended, and the suspended end is provided with the first director (1-5); the ground coplanar waveguide to substrate integrated coaxial line (1-12) is arranged at the end of the first metal surface (1-10) away from the decoupling surface (2); The second dielectric substrate (1-2) is located on the back surface of the first dielectric substrate (1-1); The third dielectric substrate (1-3) is located on the back surface of the second dielectric substrate (1-2); The back surface of the third dielectric substrate (1-3) is provided with the second metal surface (1-11), the second dipole arm (1-8), and the second director (1-9); one end of the second dipole arm (1-8) close to the decoupling surface (2) is connected to the second metal surface (1-11); the other end of the second dipole arm (1-8) is suspended, and the suspended end is provided with the second director (1-9); The metal strap (1-7) is located between the first dielectric substrate (1-1) and the second dielectric substrate (1-2); one end of the metal strap (1-7) close to the decoupling surface (2) is connected to the third dipole arm (1-6), and the other end of the third dipole arm (1-6) is suspended.

4. The antenna of claim 3, wherein, The first director (1-5) includes two metal patches with the same length and width and arranged in parallel, and a distance exists between the two metal patches; the first director (1-5) close to the first dipole arm (1-4) has a distance from the first dipole arm (1-4); the second director (1-9) includes two metal patches with the same length and width and arranged in parallel, and a distance exists between the two metal patches; the second director (1-9) close to the second dipole arm (1-8) has a distance from the second dipole arm (1-8).

5. The antenna of claim 1, wherein, The first dipole arm (1-4) and the second dipole arm (1-8) are oriented in the same direction, and the third dipole arm (1-6) is oriented in the opposite direction.

6. The antenna of claim 1, wherein, The decoupling surface (2) includes a fourth dielectric substrate (2-1) and a third metal surface (2-2) on the upper surface of the fourth dielectric substrate (2-1); The third metal surface (2-2) includes metal patches arranged in a 2x3 matrix, and a spacing exists between adjacent metal patches.

7. The antenna of claim 1, wherein The metal strip (1-7) is provided with a plurality of first metallized through holes (1-13) arranged periodically on both sides; the first metallized through holes (1-13) penetrate the first dielectric substrate (1-1), the second dielectric substrate (1-2), and the third dielectric substrate (1-3), and are used to connect the first metal surface (1-10) and the second metal surface (1-11).

8. The antenna of claim 1, wherein, The metal strip (1-7) is connected with the ground coplanar waveguide coaxial line (1-12) through a second metallized blind hole (1-14); the second metallized blind hole (1-14) penetrates the first dielectric substrate (1-1).

9. The antenna of claim 1, wherein, The top end of the metal cavity (3) is lower than the suspended end of the first dipole arm (1-4).

10. The antenna of claim 1, wherein, The first director (1-5) and the second director (1-9) have the same length and width.

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