An all-metal dual-polarization base station antenna with self-reflection performance

Abstract

The present invention belongs to the field of antenna technology, and relates to an all-metal dual-polarization base station antenna with self-reflection performance, including a low-performance frequency selective surface, a first parasitic radiator, a main radiator, a second parasitic radiator, a coaxial feeder and a metal column. The present invention adjusts the coupling effect between the three layers of radiators and sets up the antenna above the low-performance frequency selective surface, so that the performance of the base station antenna working at 1.42-2.17GHz can be met without relying on the floor. The base station antenna of the present invention reduces the complexity of the frequency selective surface design in the multi-band co-aperture base station antenna array architecture. At the same time, the present invention is an all-metal antenna with high voltage resistance and power capacity, and can be applied to more communication scenarios.

Description

Technical Field

[0001] The present invention relates to the field of antenna engineering technology, and more particularly to an all-metal dual-polarization base station antenna and array with self-reflection performance. The base station antenna's own reflection performance is utilized to get rid of dependence on ground reflection performance, and to reduce the complexity of frequency selective surface design in a multi-band common-aperture base station antenna array. Background Art

[0002] With the rapid development of modern communication systems, in order to cope with the rapidly growing demand for communication traffic and adapt to the application scenarios of the fifth-generation communication system, the performance of base station antennas needs to reach a higher level. In order to reduce the occupation of space resources and be able to work simultaneously with early communication systems, multi-band co-aperture base station antenna arrays have become the dominant trend in the development of base station antennas in the 5G era. This form can not only effectively utilize resources and reduce costs, but also meet the needs of different communication technologies and provide users with more stable and efficient communication services.

[0003] One of the commonly used multi-band co-aperture base station antenna array architectures is antenna-frequency selective surface-antenna. This architecture enables signals of different frequency bands to be effectively transmitted through the same antenna system, improving the utilization efficiency of the antenna array aperture and the overall performance of the system. However, this architecture has high requirements on the performance of the frequency selective surface. In order to achieve good passband-stopband transition performance, a multi-layer frequency selective surface cascade is usually adopted, which greatly increases the manufacturing cost and makes it difficult to meet the requirements of base station antennas for volume, weight and production cost.

[0004] In response to the above-mentioned problems, the all-metal dual-polarized base station antenna with self-reflection performance has significant advantages. First, the antenna is installed above the low-performance frequency selective surface, which can meet the various index requirements of the base station antenna without relying on the reflection performance of the floor, including unidirectionality, high gain, high cross-polarization suppression ratio and wide beam width, etc., which reduces the design difficulty of the frequency selective surface in the antenna-frequency selection-antenna co-aperture architecture. Secondly, the antenna is an all-metal base station antenna with higher voltage resistance and power capacity than the base station antenna with traditional PCB process, and can be used in more communication scenarios.

[0005] In 2024, the document “Frequency-Selective Surfaces With Quasielliptic BandpassResponse for Filtering FRA Application” proposed a frequency-selective surface with an AFA structure, which consists of two layers of antennas sandwiching a layer of floor. By introducing the radiation zero points of two patch antennas, the frequency-selective transmission zero point is obtained, achieving a high steep drop characteristic. However, it is a three-layer structure with a vertical structure, which is complex and difficult to design; in 2021, the document “Dual-Band Shared-Aperture Base Station Antenna Array With ElectromagneticTransparent Antenna Elements” proposed the concept of electromagnetic transparency. By designing a base station antenna integrated with a frequency selective surface, the electromagnetic transparency of the low-frequency antenna unit to the 3.3-3.8GHz high-frequency antenna array is achieved, with basically no effect on the radiation of the high-frequency array. However, the design complexity of electromagnetic transparency is relatively high and the bandwidth of electromagnetic transparency in the current design is relatively narrow. In 2024, the paper "Wideband Dual-Polarized Antenna With High Selectivity for 5G Sub-6-GHz Base Station Applications" proposed a filtering antenna with wide impedance bandwidth and high selectivity. The author used a grid structure and four T-shaped strips to obtain the radiation zero point, thereby achieving filtering characteristics. However, he inevitably increased the width of the base station antenna and failed to achieve the goal of compact design.

[0006] In view of the above problems, the present invention discloses an all-metal dual-polarization base station antenna with self-reflection performance. Summary of the invention

[0007] Based on the above background technology, the present invention proposes a full-metal dual-polarized base station antenna with self-reflective performance to address the deficiencies of the prior art. The antenna is composed of three layers of full-metal radiators, all of which are dual-polarized radiation. The floor on which the antenna is mounted is replaced with a low-performance frequency selective surface, achieving dual-polarized base station antenna performance. This invention reduces the dependence of the base station antenna on the reflective performance of the floor and can be better applied in the 5G communication multi-band co-aperture base station antenna scenario.

[0008] To achieve the above objectives, in a first aspect, the present invention adopts the following solutions:

[0009] The present invention provides an all-metal dual-polarization base station antenna unit with self-reflection performance, including a first parasitic radiator, a main radiator, a second parasitic radiator, a low-performance frequency selective surface, a coaxial feed line and a metal support column;

[0010] The first parasitic radiator is a first cross metal dipole sheet connected in the center, with pentagonal grooves on the four arms of the dipole and the edge and the center electrically connected by a metal strip; two first metal coupling columns are formed in a group, and the four groups are respectively located at the edges of the four arms of the first parasitic radiator; four circular holes are opened in the center of the first parasitic radiator, which respectively fix the dual-polarization port feeding coaxial line and two metal support columns.

[0011] The main radiator is a pair of orthogonally placed dual-polarized dipoles. The two arms of the dipoles in the same polarization direction are connected by metal strips, and the metal strips of one polarization are bent at the intersection to prevent contact. The dipole arms are octagonal ring-shaped metal sheets; the edges of the four arms of the main radiator are respectively fixed by the second metal coupling column extending downward; the two dipoles of the main radiator are fed by a coaxial line at the center of one arm, and the main radiator is fixed by a metal support column under the other dipole arm.

[0012] The second parasitic radiator is connected to the second cross dipole piece at the center, square grooves are opened on the four arms of the dipole and two rectangular pieces extend from the center to the four arms respectively; the metal guide column passes through and is fixed on the edge of the four arms of the cross dipole, with more exposed on the top.

[0013] Furthermore, the low-performance frequency selective surface is a single-layer simple 9×9 periodic structure printed on a dielectric substrate with a thickness of 0.8 mm and a dielectric constant of 2.2. A cylindrical through hole is set on the low-performance frequency selective surface, and the coaxial cable and the metal support column are electrically connected to the first parasitic radiator and the main radiator through the cylindrical through hole, and fixed by welding.

[0014] In the second aspect, an example of the present invention provides an all-metal dual-polarization base station antenna array with self-reflection performance, which is composed of the all-metal dual-polarization base station antenna units with self-reflection performance described in any one of claims 1-6 arranged in a 2×2 array; in the all-metal dual-polarization base station antenna array with self-reflection performance, the center spacing of the antenna units is 0.52λ; wherein λ is the wavelength corresponding to the working center frequency of the antenna.

[0015] In summary, the advantages of the present invention are:

[0016] The present invention takes into account the high complexity of the frequency selective surface design in multi-band co-aperture base station antennas, and for the first time realizes the use of the base station antenna itself to provide a certain reflection performance, reducing the demand for good steep performance of the transmission coefficient of the frequency selective surface in the design of multi-band co-aperture base station antenna arrays, getting rid of the dependence of the base station antenna on the floor, and at the same time achieving an all-metal base station antenna design, thereby improving the antenna's voltage resistance and power capacity, allowing the base station antenna to be applied to more communication scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of an all-metal dual-polarization base station antenna unit with self-reflection performance of the present invention.

[0018] Figure 2 It is a side view of an all-metal dual-polarization base station antenna unit structure with self-reflection performance of the present invention.

[0019] Figure 3 yes Figure 1 A front view of the first parasitic radiator in the antenna unit structure is shown.

[0020] Figure 4 yes Figure 1 Front view of the main radiator in the antenna unit structure shown.

[0021] Figure 5 yes Figure 1 A front view of the second parasitic radiator in the antenna unit structure is shown.

[0022] Figure 6 It is a schematic diagram of an all-metal dual-polarization base station antenna array structure with self-reflection performance of the present invention.

[0023] Figure 7 yes Figure 1 Dual-polarization port reflection coefficients for the antenna structure shown.

[0024] Figure 8 yes Figure 1 Main polarization gain curve of the antenna structure shown.

[0025] Fig. 9 yes Figure 1 Main polarization and cross-polarization gain patterns of the antenna unit shown

[0026] Fig.10 yes Figure 1 The simulation results of the front-to-back ratio of the main polarization gain pattern of the antenna structure shown.

[0027] Fig.11 yes Figure 6 The simulation results of reflection coefficient of each unit port of the antenna array shown. DETAILED DESCRIPTION

[0028] The technical solution in the example of the present invention will be described in detail below in conjunction with the accompanying drawings in the example of the present invention. The present invention includes but is not limited to the specific working states of the antenna listed below.

[0029] Reference Figure 1 , reference Figure 2 , reference Figure 3 , reference Figure 4 , reference Figure 5 .

[0030] An all-metal dual-polarization base station antenna with self-reflection performance is composed of a first parasitic radiator 1, a main radiator 2, a second parasitic radiator 3 and a low-performance frequency selective surface 4.

[0031] The first parasitic radiator 1 comprises a first cross dipole 1.1, a metal support column 1.2, a first metal coupling column 1.3 and a central opening 1.4. The first cross dipole 1.1 is connected at the center, and square grooves are opened on the four arms and the center and the edge are connected by metal strips; the metal support column passes through the first cross dipole 1.1 to fix the first parasitic radiator 1 and the main radiator 2 on the low-performance frequency selective surface 4; the central opening 1.4 facilitates the passage of the feeding coaxial line 2.2.

[0032] The main radiator 2 includes a dual-polarization dipole 2.1, a feeding coaxial line 2.2, a second metal coupling column 2.3 and a feeding metal strip 2.4. The dual-polarization dipole 2.1 is placed orthogonally, and a heptagonal slot is opened on each of the four arms; the feeding coaxial line 2.2 is fed at the center of the dual-polarization dipole, and the inner conductor is connected to the corresponding dipole arm by the feeding metal strip 2.4; the second metal coupling column 2.3 is fixed at the edge of the four arms of the dual-polarization dipole, which can adjust the coupling with the first parasitic radiator to achieve unidirectional radiation performance.

[0033] The second parasitic radiator 3 includes a second cross dipole 3.1 and a metal guide post 3.2. The second cross dipole 3.1 is connected at the center, and square slots are respectively opened on the four arms and two metal strips extend from the center; the metal guide post 3.2 passes through and is fixed on the edge of the four arms of the dipole to play a guiding role and improve the unidirectional performance of the antenna.

[0034] The low-performance frequency selective surface 4 is a single-layer 9×9 periodic structure printed on a 0.8 mm thick dielectric substrate. The dielectric substrate material is Rogers duroid 5880, with a relative dielectric constant of 2.2. The distance from the first parasitic radiator 1 is 0.05λ; where λ is the wavelength corresponding to the working center frequency of the antenna.

[0035] Reference Figure 6The all-metal dual-polarization base station antenna array with self-reflection performance is composed of the above-mentioned all-metal dual-polarization base station antenna units arranged in a 2×2 manner; in the all-metal dual-polarization base station antenna array with self-reflection performance, the center spacing of the antenna units is 0.52λ; wherein λ is the wavelength corresponding to the working center frequency of the antenna.

[0036] The antenna performance is further described in detail below with reference to the accompanying drawings:

[0037] Figure 7 : is the reflection coefficient of the dual-polarization base station antenna in the LB frequency band in the above implementation mode, where the horizontal axis is the frequency and the vertical axis is the reflection coefficient.

[0038] Figure 8 This is a main polarization gain curve of the dual-polarization base station antenna in the LB frequency band of the above implementation mode.

[0039] Fig. 9 The main polarization and cross-polarization gain patterns of the dual-polarization base station antenna in the LB frequency band of the above implementation manner.

[0040] Fig.10 It is a simulation result diagram of the front-to-back ratio of the main polarization gain pattern of the dual-polarization base station antenna in the LB frequency band in the above implementation mode.

[0041] Fig.11 It is a diagram showing the simulation results of the reflection coefficient of each unit port of the dual-polarization base station antenna array in the LB frequency band according to the above implementation mode.

[0042] The above description and implementation methods are only some preferred examples of the present invention and do not constitute any limitation to the present invention. For professionals in this field, the present application may have various modifications and changes, but the modifications and changes based on the ideas of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. An all-metal dual-polarization base station antenna with self-reflection performance, characterized in that: The invention comprises a low-performance frequency selective surface, a first parasitic radiator, a main radiator, and a second parasitic radiator which are sequentially placed from bottom to top; the first parasitic radiator is fixed above the simple low-performance frequency selective surface; the main radiator is fixed above the first parasitic radiator by a metal column; the second parasitic radiator is fixed above the main radiator; The first parasitic radiator comprises a first metal sheet, a metal support column and a first metal coupling column; rectangular grooves are dug on the four arms of the first metal sheet, and the edges and the center are electrically connected through metal strips; the metal support column passes through the first parasitic radiator, is fixed to the low-performance frequency selective surface at the bottom, and is connected to the main radiator at the top, so as to support the first parasitic radiator and the main radiator; the first metal coupling columns are grouped in two, and the four groups are respectively fixed to the edges of the four arms of the first parasitic radiator; The main radiator includes a pair of dipole metal sheets, a feeding coaxial line, a feeding metal strip and a second coupling metal column; the dipole metal sheet is an octagonal structure, and the dipole arms in the same direction are connected by the feeding metal strip; the feeding coaxial line passes through the dipole metal sheet, and the inner conductor is connected to the other arm of the dipole through the feeding metal strip; the second coupling metal column is four rectangular parallelepiped columns, which are respectively fixed below the edges of the four arms of the dipole; The second parasitic radiator includes a second metal sheet and a metal guide column; the second metal sheet is composed of two dipoles placed crosswise and connected at the center, square grooves are opened on the four arms of the dipole, and two parallel rectangular metal sheets extend from the center to the four arms respectively; the metal guide column is a cylindrical metal column fixed and passing through the edge of the second metal sheet.

2. The all-metal dual-polarization base station antenna with self-reflection performance according to claim 1, characterized in that: In an all-metal dual-polarization base station antenna array with self-reflection performance, the horizontal spacing between the center points of the antenna units is 0.52λ; wherein λ is the wavelength corresponding to the working center frequency of the antenna.

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