WO2024066393A1

WO2024066393A1 - Low-frequency filtering radiating element and base station antenna

Info

Publication number: WO2024066393A1
Application number: PCT/CN2023/094762
Authority: WO
Inventors: 刘正贵; 程伟; 吴卫华
Original assignee: 中信科移动通信技术股份有限公司
Priority date: 2022-09-30
Filing date: 2023-05-17
Publication date: 2024-04-04
Also published as: CN115377657A; EP4372911A1

Abstract

The present disclosure provides a low-frequency filtering radiating element and a base station antenna. The low-frequency filtering radiating element comprises: a substrate, the substrate comprising a first mounting surface and a second mounting surface which are oppositely arranged; and a low-frequency radiating element, comprising four pairs of dipoles centrosymmetrically distributed on the substrate; the four pairs of dipoles are in orthogonal polarization distribution so as to form two groups of radiating elements polarized at +/-45 degrees; each pair of dipoles comprises two radiating arms respectively arranged on the first mounting surface and the second mounting surface, and the two radiating arms are arranged in a mirror image manner.

Description

Low frequency filtering radiation unit and base station antenna

CROSS-REFERENCE TO RELATED APPLICATIONS

This disclosure claims priority to Chinese patent application No. 2022112168258 filed with the China National Intellectual Property Administration on September 30, 2022, and titled “Low-frequency filtering radiation unit and base station antenna”, and the entire contents of the Chinese patent application disclosure are incorporated herein by reference.

Technical Field

The present disclosure relates to the technical field of communication equipment, and in particular to a low-frequency filtering radiation unit and a base station antenna.

Background technique

The radiating unit is the main part of the antenna, which can transmit and receive electromagnetic waves in a direction, thereby realizing wireless communication. The dual-polarized radiating unit can realize polarization diversity and can work in the duplex mode at the same time, greatly reducing the number of antennas and the space occupied. At present, the integration of multi-frequency antennas in the industry is getting higher and higher. In a limited space, a variety of vibrators with different frequency bands must be arranged. The existing high- and low-frequency fusion solutions include low-frequency bowl-shaped nesting and cross-cross vibrators. The low-frequency bowl-shaped nesting solution has excellent performance but the array method is fixed, and the cross-cross vibrator solution has flexible array formation but poor indicators. Therefore, designing a low-frequency radiating unit with simple structure, excellent performance and little impact on high frequency is an urgent problem that technicians in this field need to solve.

Summary of the invention

According to an embodiment of the present disclosure, a low-frequency filtering radiation unit is provided, comprising:

a substrate, the substrate comprising a first mounting surface and a second mounting surface which are arranged opposite to each other; and

The low-frequency radiation unit includes four pairs of dipoles symmetrically distributed on the substrate. The dipoles are orthogonally distributed in polarization to form two groups of ±45° polarized radiation units. Each pair of dipoles includes two radiation arms respectively arranged on the first mounting surface and the second mounting surface, and the two radiation arms are arranged in a mirror image.

According to a low-frequency filtering radiation unit provided by the present disclosure, a feeding unit is also provided on the first mounting surface and the second mounting surface respectively, and the feeding unit includes four baluns distributed orthogonally, each balun is connected to a corresponding radiation arm, and two baluns on the same extension line in each feeding unit are cascaded at the center position of the substrate.

According to a low-frequency filtering radiation unit provided by the present disclosure, each balun is provided with at least one filtering branch, and the filtering branch is used to reduce the influence of the low-frequency radiation unit on the high-frequency oscillator.

According to a low-frequency filtering radiation unit provided by the present disclosure, each filter branch forms a plurality of filter branch groups, each filter branch group is spaced in sequence along the length direction of the corresponding balun, and the two filter branches of each filter branch group are symmetrically arranged on both sides of the corresponding balun spaced in the length direction.

According to a low-frequency filtering radiation unit provided by the present disclosure, each filtering branch is in a straight line, a curve or an L shape.

According to a low-frequency filtering radiation unit provided by the present disclosure, each radiation arm includes a plurality of filtering components and an inductor branch connecting the filtering components.

According to a low-frequency filtering radiation unit provided in the present disclosure, the low-frequency filtering radiation unit also includes a supporting seat, the supporting seat includes a base and two feeding substrates arranged on the base, the two feeding substrates are orthogonally distributed and correspondingly connected to the feeding unit on the second mounting surface.

According to a low-frequency filtering radiation unit provided by the present disclosure, a feeding circuit is provided inside each balun, and each feeding circuit is used to feed the corresponding radiation arm through a coaxial line and/or a feeder pad.

The present disclosure also provides a base station antenna, comprising:

Pedestal;

A high-frequency radiation unit includes a plurality of high-frequency vibrators arranged on a base; and

The low-frequency filtering radiation unit is arranged between the high-frequency oscillators at intervals, and the low-frequency filtering radiation unit is any of the low-frequency filtering radiation units described above.

According to a base station antenna provided by the present disclosure, the spacing between each high-frequency oscillator is 0.7-0.9λ.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solution of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

FIG1 is a schematic diagram of a three-dimensional structure of a low-frequency filtering radiation unit according to an embodiment of the present disclosure;

FIG2 is a schematic diagram of the front structure of the substrate in FIG1 ;

FIG3 is a schematic diagram of the back structure of the substrate in FIG1 ;

FIG4 is a schematic diagram of the three-dimensional structure of a base station antenna according to an embodiment of the present disclosure;

Figure numerals: 10: base station antenna; 100: low-frequency filtering radiation unit; 110: substrate; 111: first mounting surface; 112: second mounting surface; 120: low-frequency radiation unit; 121: dipole; 122: radiation arm; 123: filter element; 124: inductor branch; 130: feeding unit; 131: balun; 132: filtering branch; 140: supporting base; 141: feeding substrate; 142: base; 200: base; 300: high-frequency radiation unit; 310: high-frequency oscillator.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the technical solutions in the present disclosure will be clearly described below in conjunction with the drawings in the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

In the description of the embodiments of the present disclosure, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present disclosure. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

In the description of the embodiments of the present disclosure, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to specific circumstances.

In the embodiments of the present disclosure, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the disclosed embodiment. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be used interchangeably. Materials or features may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without contradicting each other.

The low-frequency filtering radiation unit 100 and the base station antenna 10 of the embodiment of the present disclosure are described below in conjunction with FIG. 1 to FIG. 4 .

In the existing multi-frequency fusion antenna, the low-frequency radiating unit is larger in size than the high-frequency one, so the high-frequency index is always deteriorated in the multi-frequency fusion system. In view of this, the present disclosure provides a low-frequency filtering radiating unit 100, including: a substrate 110, the substrate 110 includes a first mounting surface 111 and a second mounting surface 112 which are arranged opposite to each other; and a low-frequency radiating unit 120, including four pairs of dipoles 121 centrally symmetrically distributed on the substrate 110, the four pairs of dipoles 121 are orthogonally distributed in polarization to form two groups of radiating units with ±45° polarization, each pair of dipoles 121 includes two radiating arms 122 which are respectively arranged on the first mounting surface 111 and the second mounting surface 112, and the two radiating arms 122 are arranged in a mirror image.

The low-frequency filter radiation unit 100 is a unit constituting the basic structure of the antenna, which can effectively radiate or receive radio waves. Among them, the preparation material of the low-frequency filter radiation unit 100 can be set according to actual needs, such as being made of PCB (Printed Circuit Board) or metal die-casting plate, and accordingly, the substrate 110 is PCB or metal die-casting plate. The dielectric thickness and dielectric constant of the substrate 110 and other related parameters can be set according to actual needs, such as setting the dielectric thickness of the substrate 110 between 0.2mm and 3mm, and the dielectric constant between 2 and 10.

The low-frequency filtering radiation unit 100 provided by the present invention has two groups of radiation units with ±45° polarization. The radiation unit composed of two dipoles 121 has not only better unit radiation performance but also more stable array performance compared to the ordinary single dipole 121 cross antenna. Moreover, compared with the bowl-shaped vibrator, the low-frequency filtering radiation unit 100 provided by the present invention has high integration, small installation area, more flexible array, and can significantly improve the applicability of the radiation unit.

Alternatively, a feeding unit 130 is also provided on the first mounting surface 111 and the second mounting surface 112, respectively. The feeding unit 130 includes four baluns 131 distributed orthogonally, each balun 131 is connected to a corresponding radiation arm 122, and two baluns 131 on the same extension line in each feeding unit 130 are cascaded at the center position of the substrate 110, so that the two dipoles 121 on the same extension line form a radiation unit with ±45° polarization. Furthermore, at least one filter branch 132 is provided on each balun 131, and the filter branch 132 is used to reduce the influence of the low-frequency radiation unit 120 on the high-frequency oscillator. It should be noted that the number and shape of the filter branches 132 can be set according to actual needs, such as setting one or more filter branches 132 of different shapes, different lengths and different widths, and the filter branches 132 can be linear, curved or L-shaped, which is not specifically limited in this embodiment. Alternatively, in this embodiment, the filter branches 132 form a plurality of filter branch groups, each filter branch group being spaced in sequence along the length direction of the corresponding balun 131, and the two filter branches 132 of each filter branch group being symmetrically arranged on both sides of the corresponding balun 131 spaced in the length direction, and the filter branches 132 are L-shaped.

In the prior art, the decoupling between the vibrators of different frequency bands is mainly achieved by adding isolation strips, barriers, devices or PCB boards and other filtering means between the vibrators of different frequency bands in the form of circuits in the feed network part, so as to reduce the coupling between the vibrators of different frequency bands as much as possible. However, this method not only requires adding a large number of filtering devices between the vibrators, which occupies a large amount of space, but also results in a small space occupied by each vibrator on the antenna, affecting the overall layout of each vibrator on the antenna, resulting in the difficulty of the antenna to meet the number of frequency bands, or the effect of eliminating interference is difficult to meet the expected requirements. Therefore, in the technical solution provided by the present disclosure, each radiating arm 122 includes a plurality of filtering elements 123 and an inductor branch 124 connecting each filtering element 123. By adding a filtering element 123 inside the radiating arm 122 to achieve a filtering effect, the radiating arm 122 itself has a certain filtering effect on the interference of other frequency bands, avoiding changing the arrangement of the radiating arm 122 on the antenna and occupying additional space of the antenna.

It should be noted that the number and shape of the filter elements 123 of each radiating arm 122 can be The configuration is performed according to actual needs, such as configuring one or more filter elements 123 of different shapes, lengths, and widths, and the filter elements 123 are connected by inductor branches 124, which is not specifically limited in this embodiment. In this embodiment, the radiation arm 122 is configured as a rectangle, the filter element 123 is correspondingly configured as a rectangle, and the inductor branch 124 is configured as a long strip for connecting the filter elements 123.

Furthermore, the low-frequency filtering radiation unit 100 further includes a support base 140, the support base 140 includes a base 142 and two feeding substrates 141 arranged on the base 142, the two feeding substrates 141 are orthogonally distributed and correspondingly connected to the feeding unit 130 on the second mounting surface 112, and are used to feed the balun 131, and the feeding substrate 141 is a PCB or a metal die-casting plate, which is not limited in the present disclosure. Alternatively, a feeding circuit is provided inside the balun 131, and the feeding circuit is used to feed the corresponding radiation arm 122 through a coaxial line and/or a feeder pad.

On the basis of the above-mentioned low-frequency filter radiation unit 100, the present disclosure further provides a base station antenna 10, comprising: a base 200; a high-frequency radiation unit 300, comprising a plurality of high-frequency oscillators 310 disposed on the base 200; and a low-frequency filter radiation unit 100, which is disposed between the high-frequency oscillators 310 at intervals. The spacing between the high-frequency oscillators 310 is 0.7 to 0.9λ. Since the main improvement of the present disclosure lies in the low-frequency filter radiation unit 100, the detailed structure of the base station antenna 10 will not be described in detail.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

A low-frequency filtering radiation unit, comprising:

A substrate, the substrate comprising a first mounting surface and a second mounting surface arranged opposite to each other; and

The low-frequency radiation unit includes four pairs of dipoles centrally and symmetrically distributed on the substrate, wherein the four pairs of dipoles are orthogonally distributed in polarization to form two groups of radiation units polarized at ±45°, and each pair of the dipoles includes two radiation arms respectively arranged on the first mounting surface and the second mounting surface, and the two radiation arms are arranged in a mirror image.
According to the low-frequency filtering radiation unit according to claim 1, wherein the first mounting surface and the second mounting surface are respectively provided with a feeding unit, and the feeding unit includes four orthogonally distributed baluns, each of the baluns is connected to a corresponding radiating arm, and two of the baluns on the same extension line in each feeding unit are cascaded at the center position of the substrate.
The low-frequency filtering radiation unit according to claim 2, wherein each of the baluns is provided with at least one filtering branch.
According to the low-frequency filtering radiation unit according to claim 3, each of the filter branches forms a plurality of filter branch groups, each of the filter branch groups is spaced in sequence along the length direction of the corresponding balun, and the two filter branches of each filter branch group are symmetrically arranged on both sides of the corresponding balun spaced in the length direction.
The low-frequency filtering radiation unit according to claim 4, wherein each of the filtering branches is linear, curved or L-shaped.
The low-frequency filtering radiation unit according to claim 2, wherein each of the radiation arms comprises a plurality of filtering elements and an inductor branch connecting each of the filtering elements.
The low-frequency filter radiation unit according to claim 2, wherein the low-frequency filter radiation unit further comprises a support seat, the support seat comprises a base and two feed substrates arranged on the base, the two feed substrates are orthogonally distributed and are connected to the second arrangement The feeding units on the mounting surface are connected accordingly.
The low-frequency filtering radiation unit according to claim 2, wherein a feeding circuit is provided inside each of the baluns, and each of the feeding circuits is used to feed the corresponding radiating arm through a coaxial line and/or a feed line pad.
A base station antenna, comprising:

Pedestal;

A high-frequency radiation unit, comprising a plurality of high-frequency vibrators arranged on the base; and

A low-frequency filtering radiation unit is arranged between the high-frequency oscillators at intervals, and the low-frequency filtering radiation unit is the low-frequency filtering radiation unit as described in any one of claims 1-8.
The base station antenna according to claim 9, wherein the spacing between each of the high-frequency oscillators is 0.7 to 0.9λ.