A low cross-polarization wide-beam dual-polarized antenna

Abstract

The application discloses a kind of low cross-polarization wide-beam dual-polarized antennas, belong to microwave antenna technical field.The antenna of the application adopts dual-polarization design, can simultaneously have excellent radiation performance in two polarized directions;Through the radiation structure and feed network of reasonable design, antenna unit realizes extremely low cross-polarization, so that in the application of array, even at low elevation, still have stable beam and antenna directivity.The application is manufactured using PCB process, reduces manufacturing cost, and is suitable for mass production and integration;Through the structural optimization design of antenna, it has excellent cross-polarization performance, so that it can still maintain below-25dB cross-polarization level in dual-polarization state;With relatively wide half-beam width, so that in the application of array, even at low elevation, still have stable beam and antenna directivity.The application can be applied to radar, wireless communication and other fields, and has wide application prospect.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of microwave antennas, and particularly relates to a low-cross-polarization wide-beam dual-polarized antenna. BACKGROUND

[0002] With the continuous development of wireless communication and radar systems, antenna technology plays a crucial role in improving system performance. In particular, in modern phased array radars and communication systems, wide-angle scanning and dual-polarization capability have become key requirements. Wide-angle scanning can significantly improve the coverage range and target detection capability of the system, while dual-polarized antennas can provide more abundant signal information, improving the system's anti-jamming capability and data transmission rate.

[0003] In the prior art, dual-polarized antennas are mainly manufactured using low-temperature co-fired ceramic (LTCC) technology. LTCC technology has excellent high-frequency performance and is suitable for manufacturing small and highly integrated antennas. However, LTCC technology has some obvious drawbacks, such as high manufacturing cost, complex process, and low yield, which limit its application in large-scale production. In addition, due to the limitations of LTCC materials and processes, it is difficult to achieve performance optimization of wide beams and low cross-polarization in large-size antenna arrays.

[0004] In contrast, printed circuit board (PCB) technology has gradually gained attention in antenna design due to its mature manufacturing technology, low cost, and ease of large-scale integration. PCB technology has been widely used in the manufacture of various single-polarized antennas, but in dual-polarized antennas, especially in wide-beam and low-cross-polarization antennas, relevant research and applications are still relatively limited. Existing PCB technology dual-polarized antennas are still insufficient in cross-polarization or isolation performance, limiting their application in high-performance phased array systems. SUMMARY

[0005] The purpose of the present application is to solve the deficiencies of existing dual-polarized antennas in array wide-angle scanning and wide-beam coverage applications, especially in terms of cost, cross-polarization performance, bandwidth, and beam stability. The present application provides a low-cross-polarization wide-beam dual-polarized antenna that achieves excellent performance at a lower cost through optimized design and process selection, suitable for array applications.

[0006] The technical problem of the present application is solved as follows:

[0007] A low-cross-polarization wide-beam dual-polarized antenna includes a metal patch 1, a metal column 2, a feed probe 3, an upper layer dielectric substrate 4, a prepreg 5, a lower layer dielectric substrate 6, and a metal ground plate. The upper layer dielectric substrate 4, the prepreg 5, and the lower layer dielectric substrate 6 are tightly attached from top to bottom. The metal ground plate is located on the lower surface of the lower layer dielectric substrate 6.

[0008] The four metal patches 1 are square, located on the upper surface of the upper dielectric substrate 4, symmetrically arranged about the center position of the upper surface of the upper dielectric substrate 4, and parallel to the edges of the upper dielectric substrate 4; the corners closest to the center position of the upper surface of the upper dielectric substrate 4 of each metal patch 1 are scalloped.

[0009] The metal column 2 includes eight magnetic dipole metal columns, two feeding coaxial probes, and a plurality of peripheral metal through holes, which penetrate the upper dielectric substrate 4, the prepreg 5, and the lower dielectric substrate 6, and reach from the upper surface of the upper dielectric substrate 4 to the lower surface of the lower dielectric substrate 6; the eight magnetic dipole metal columns are uniformly and symmetrically distributed at the positions of the four metal patches 1; the two feeding coaxial probes are located at the scalloped corners of the adjacent two metal patches 1; and the plurality of peripheral metal through holes are uniformly distributed at the gaps between the four metal patches 1 and the edges of the upper dielectric substrate 4.

[0010] The feeding probe 3 includes a Y-shaped probe and a V-shaped probe, which are located on the upper surface of the upper dielectric substrate 4; the two branches of the Y-shaped probe are at a 90° angle and are parallel to the edges of any metal patch 1 with a spacing, and the end of the third branch is electrically connected to the feeding coaxial probe at the diagonal position of the metal patch 1; the two branches of the V-shaped probe are at a 90° angle and are parallel to the edges of the metal patch 1 at the diagonal position of the other feeding coaxial probe with a spacing, and the connection between the two branches of the V-shaped probe is connected to the other feeding coaxial probe through a metallized through hole on the lower surface of the upper dielectric substrate 4.

[0011] Further, a coaxial feeding method is adopted, and the inner cores of the two coaxial lines are connected to the two feeding coaxial probes, and the outer layer is connected to the metal floor.

[0012] Further, the magnetic dipole metal column is located inside the scalloped corner of the metal patch 1.

[0013] Further, the relative dielectric constants of the upper dielectric substrate 4 and the lower dielectric substrate 6 are 3, and the thicknesses are 0.254 mm and 1.27 mm, respectively.

[0014] Further, the prepreg 5 is selected to be RO4450F prepreg, and the thickness is 0.1 mm.

[0015] Further, the metal patch 1 is selected to be gold, the edge length is 1.8 mm, the edge spacing between adjacent metal patches 1 is 0.9 mm, the distance between the magnetic dipole metal column and the two edges of the metal patch 1 is 0.3 mm and 0.9 mm, respectively, the radius of the peripheral metal through hole is 0.2 mm, and the center spacing between adjacent peripheral metal through holes is 1.76 mm.

[0016] The beneficial effects of the present application are:

[0017] (I) ±45° dual-polarization design suitable for base station and other application scenarios

[0018] The dual-polarization antenna unit of the present application is particularly suitable for the ±45° dual-polarization scheme commonly used in scenarios such as base stations. This polarization method can significantly improve the polarization diversity effect of base station antennas, thereby improving the anti-interference ability and signal reception quality of wireless communication systems. In modern communication networks, the ±45° dual-polarization technology is widely used to improve spectral efficiency and enhance signal isolation between multiple users. The antenna structure of the present application, through precise polarization design, can ensure that the base station can provide stable dual-polarization signal coverage and effectively reduce polarization cross-interference in actual deployment, thereby improving the overall performance of the communication system.

[0019] (II) Wideband and wide-beam characteristics achieved by using a magneto-electric dipole structure

[0020] The antenna of the present application uses an innovative magneto-electric dipole structure, which can simultaneously achieve wideband and wide-beam characteristics in antenna design. The magneto-electric dipole has unique electromagnetic field distribution characteristics, allowing the antenna to maintain good matching and radiation characteristics over a wider frequency range, avoiding the performance degradation problem of traditional antennas at the upper and lower edges of the operating frequency band. In addition, the wide-beam characteristic ensures that the antenna has stable radiation intensity in different directions, which is particularly suitable for application in wide-angle scanning arrays, allowing the array to maintain uniform signal coverage over a large angle.

[0021] (III) The antenna patch is treated with a cut corner to significantly improve cross-polarization performance

[0022] The present application uses a cut corner treatment in the antenna patch part to make the antenna's radiation patch more symmetrical. This symmetrical design greatly improves the cross-polarization performance of the antenna. Cross-polarization is an important indicator in antenna design, especially in dual-polarization antennas, where low cross-polarization can minimize signal interference between the two polarization directions. The present application effectively reduces the cross-polarization level of the antenna through cut corner treatment, allowing it to maintain high polarization purity under different operating conditions. This optimization design further improves the transmission quality of signals and the robustness of the system in a multipath transmission environment.

[0023] (IV) Increase metal columns to expand beam coverage and optimize antenna radiation characteristics

[0024] The application loads several metal columns around the antenna, which interact with the magnetic electric dipole radiation field of the antenna, effectively improving the edge radiation characteristics, and further increasing the antenna beam width. This design optimizes the antenna pattern, maintains stable radiation characteristics in a wide beam range, and is particularly suitable for wide-angle scanning arrays. Through the design of this structure, the signal coverage at the scanning angle can still be ensured during wide-angle scanning after arraying, reducing the "blind area" phenomenon and improving the overall system performance. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a schematic diagram of a magnetic electric dipole basic theoretical model;

[0026] Figure 2 is a top view of the antenna according to the application;

[0027] Figure 3 is a three-dimensional view of the antenna according to the application;

[0028] Figure 4 is a design flowchart of the antenna according to the application;

[0029] Figure 5 is a port standing wave ratio curve diagram of the antenna according to the embodiment;

[0030] Figure 6 is an E-plane H-plane co-polarization and cross-polarization pattern of the antenna according to the embodiment at 24GHz;

[0031] Figure 7 is an E-plane H-plane co-polarization and cross-polarization pattern of the antenna according to the embodiment at 27GHz;

[0032] Figure 8 is an E-plane H-plane co-polarization and cross-polarization pattern of the antenna according to the embodiment at 30GHz. DETAILED DESCRIPTION

[0033] The application will be further described below in combination with the drawings and embodiments.

[0034] The embodiment provides a low cross-polarization wide-beam dual-polarization antenna, whose top view and three-dimensional view are shown in Figure 2 and Figure 3 respectively, which comprises a metal patch 1, a metal column 2, a feeding probe 3, an upper layer dielectric substrate 4, a prepreg 5, a lower layer dielectric substrate 6 and a metal ground plate; the upper layer dielectric substrate 4, the prepreg 5 and the lower layer dielectric substrate 6 are closely adhered from top to bottom; the metal ground plate is located on the lower surface of the lower layer dielectric substrate 6;

[0035] The four metal patches 1 are square, located on the upper surface of the upper dielectric substrate 4, symmetrically arranged about the center position of the upper surface of the upper dielectric substrate 4, and parallel to the edges of the upper dielectric substrate 4; and the corners closest to the center position of the upper surface of the upper dielectric substrate 4 of each metal patch 1 are cut into sectors.

[0036] The metal column 2 includes eight magnetic dipole metal columns, two feeding coaxial probes, and a plurality of peripheral metal through holes, which penetrate through the upper dielectric substrate 4, the prepreg 5, and the lower dielectric substrate 6, and reach from the upper surface of the upper dielectric substrate 4 to the lower surface of the lower dielectric substrate 6; the eight magnetic dipole metal columns are uniformly and symmetrically distributed at the positions of the four metal patches 1; the two feeding coaxial probes are located at the cut corners of the adjacent two metal patches 1; and the plurality of peripheral metal through holes are uniformly distributed at the gaps between the four metal patches 1 and the edges of the upper dielectric substrate 4.

[0037] The feeding probe 3 includes a Y-shaped probe and a V-shaped probe, which are located on the upper surface of the upper dielectric substrate 4; the two branches of the Y-shaped probe are at a 90° angle and are parallel to the edges of any metal patch 1 with a spacing, and the end of the third branch is electrically connected to the feeding coaxial probe at the diagonal position of the metal patch 1; the two branches of the V-shaped probe are at a 90° angle and are parallel to the edges of the metal patch 1 at the diagonal position of the other feeding coaxial probe with a spacing, and the connection between the two branches of the V-shaped probe is connected to the other feeding coaxial probe through a metallized through hole on the lower surface of the upper dielectric substrate 4.

[0038] In this embodiment, the relative dielectric constants of the upper dielectric substrate 4 and the lower dielectric substrate 6 are 3, and the thicknesses are 0.254 mm and 1.27 mm, respectively; the prepreg 5 is selected as RO4450F prepreg, and the thickness is 0.1 mm.

[0039] The material of the electric dipole metal patch 1 is gold, the side length is 1.8 mm, and the edge spacing between adjacent metal patches 1 is 0.9 mm; the distances between the magnetic dipole metal column and the two edges of the metal patch 1 are 0.3 mm and 0.9 mm, respectively; the radius of the peripheral metal through hole is 0.2 mm, and the center spacing between adjacent peripheral metal through holes is 1.76 mm.

[0040] The antenna described in this embodiment adopts a coaxial feeding mode, the inner cores of the two coaxial lines are respectively connected to the two feeding coaxial probes, and the outer layer is connected to the metal floor.

[0041] In the antenna described in the embodiment, the four symmetrical metal patches 1 act as electric dipoles, and the eight symmetrical magnetic dipole metal columns act as magnetic dipoles, which are fed by Y-shaped probes and V-shaped probes, respectively. In the antenna described in the embodiment, the feeding probes can provide a relatively symmetrical polarization direction on the one hand, and make the antenna feeding at the same height on the other hand, thereby reducing the complexity of the antenna structure. Compared with the L-shaped probe direct feeding in the prior art, the feeding probe in the embodiment does not damage the patch metal antenna structure, thereby introducing the influence of the slot radiation mode, and further affecting the radiation characteristics of the antenna.

[0042] The upper surface structure of the upper layer dielectric substrate 4 acts as a magnetoelectric dipole, and the basic structure of the magnetoelectric dipole is as shown in Figure 1 The electric dipole electric field and the magnetic dipole electric field and magnetic field are superimposed, and finally the same radiation field is formed in the horizontal plane and the vertical plane.

[0043] In the antenna described in the embodiment, each metal patch 1 is cut into a fan shape, the coupling between the feeding probe and the magnetic dipole metal column is enhanced, and thus the cross polarization is reduced. A plurality of peripheral metal through holes are loaded between the four metal patches and the edge of the upper layer dielectric substrate, which are used for controlling the antenna current distribution and thus controlling the edge radiation of the antenna, and improving the beam width of the antenna.

[0044] Through the above design, the antenna has good application value while ensuring high performance of the antenna, simplifying the structure and reducing the manufacturing cost.

[0045] The design flowchart of the antenna is as shown in Figure 4 , and includes the following steps:

[0046] Step 1. Determine the antenna index according to the specific requirement, such as frequency, half beam width, etc.

[0047] Step 2. Calculate the antenna metal patch width and the antenna height according to the determined parameters.

[0048] Specifically, the corresponding spatial free wavelength λ is calculated according to the antenna center frequency, the antenna height h is one quarter of the calculated wavelength λ, and the side length w of the metal patch and the gap s between the adjacent patches satisfy Wherein ε r is the relative dielectric constant of the upper layer substrate.

[0049] Step 3. Model in the electromagnetic simulation software according to the approximate parameters in step 2, set appropriate boundary conditions and simulation settings, and complete the antenna time domain difference algorithm simulation.

[0050] Step 4. Adjust the simulation parameters according to the simulation results in step 3, and optimize the required index.

[0051] Step 5. The processing test of the antenna is completed, and a required low cross-polarization wide-beam dual-polarized antenna is obtained.

[0052] The standing wave ratio obtained by simulating the antenna in the embodiment is as shown in Figure 5 The co-polarization and cross-polarization results at 24 GHz, 27 GHz and 30 GHz are as shown in Figure 6 、 Figure 7 and Figure 8 It can be seen from Figure 5 that the standing wave ratio of the antenna in the embodiment is less than 2 in the frequency range of 24 GHz-30 GHz, indicating that the antenna can normally work in the frequency range. It can be seen from Figures 6-8 that the one-port and two-port antenna patterns at 24 GHz, 27 GHz and 30 GHz are highly consistent, the antenna has dual-polarization characteristics, the H-plane antenna half-beam width is greater than 130°, the cross-polarization is less than -25 dB within the range of ±60°, and the antenna has the characteristics of wide band, wide beam and high cross-polarization suppression.

[0053] In summary, the dual-polarized low cross-polarization wide-beam antenna based on the PCB process is developed to make up for the shortcomings of the prior art, and has important technical significance and application value. The antenna has the characteristics of maintaining good beam characteristics under the condition of wide-angle scanning after array, can effectively reduce cross-polarization, realize stable performance under dual-polarization, has low manufacturing cost and high production capacity, and is suitable for large-scale array application.

Claims

1. A low cross-polarization wide beam dual-polarization antenna, characterized in that: The invention comprises a metal patch (1), a metal column (2), a feeding probe (3), an upper dielectric substrate (4), a prepreg (5), a lower dielectric substrate (6) and a metal floor; the upper dielectric substrate (4), the prepreg (5) and the lower dielectric substrate (6) are tightly attached in sequence from top to bottom; and the metal floor is located on the lower surface of the lower dielectric substrate (6); Four metal patches (1) are square in shape and are located on the upper surface of the upper dielectric substrate (4). They are symmetrically arranged about the center position of the upper surface of the upper dielectric substrate (4), and the edge of each metal patch (1) is parallel to the edge of the upper substrate (4). The corner of each metal patch (1) closest to the center position of the upper surface of the upper dielectric substrate (4) is fan-shaped cut. The metal column (2) includes eight magnetic dipole metal columns, two feeding coaxial probes and a plurality of peripheral metal through-holes. The metal column (2) penetrates the upper dielectric substrate (4), the semi-cured sheet (5) and the lower dielectric substrate (6), and reaches the lower surface of the lower dielectric substrate (6) from the upper surface of the upper dielectric substrate (4). The eight magnetic dipole metal columns are evenly and symmetrically distributed at the inner positions of the cut corners of the four metal patches (1). The two feeding coaxial probes are located at the cut corners of two adjacent metal patches (1). The plurality of peripheral metal through-holes are evenly distributed in the gaps between the four metal patches (1) and the edges of the upper dielectric substrate (4). The feeding probe (3) includes a Y-shaped probe and a V-shaped probe, which are located on the upper surface of the upper dielectric substrate (4); the two branches of the Y-shaped probe form a 90° angle between each other, are parallel to the edge of any metal patch (1) and leave a gap, and the end of the third branch is electrically connected to the feeding coaxial probe at the diagonal position of the metal patch (1); the two branches of the V-shaped probe form a 90° angle between each other, are parallel to the edge of the metal patch (1) at the diagonal position of the other feeding coaxial probe and leave a gap, and the connection between the two branches of the V-shaped probe is connected to the other feeding coaxial probe on the lower surface of the upper dielectric substrate (4) through a metallized through-hole.

2. The low cross-polarization wide beam dual-polarization antenna according to claim 1, wherein: The coaxial feeding method is adopted. The inner cores of the two coaxial cables are respectively connected to the two feeding coaxial probes, and the outer layer is connected to the metal floor.

3. The low cross-polarization wide beam dual-polarization antenna according to claim 1, wherein: The relative dielectric constant of the upper dielectric substrate (4) and the lower dielectric substrate (6) is 3, and the thicknesses are 0.254 mm and 1.27 mm respectively.

4. The low cross-polarization wide beam dual-polarization antenna according to claim 1, wherein: The prepreg (5) is RO4450F prepreg with a thickness of 0.1 mm.

5. The low cross-polarization wide beam dual-polarization antenna according to claim 1, wherein: The metal patch (1) is made of gold, has a side length of 1.8 mm, and the edge spacing between adjacent metal patches (1) is 0.9 mm; the distances between the two sides of the magnetic dipole metal column and the metal patch (1) are 0.3 mm and 0.9 mm respectively; the radius of the peripheral metal through hole is 0.2 mm, and the center spacing between adjacent peripheral metal through holes is 1.76 mm.

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