EP4372911A1

EP4372911A1 - Low-frequency filtering radiating element and base station antenna

Info

Publication number: EP4372911A1
Application number: EP23798323.4A
Authority: EP
Inventors: Zhenggui LIU; Wei Cheng; Weihua Wu
Original assignee: CICT Mobile Communication Technology Co Ltd
Current assignee: CICT Mobile Communication Technology Co Ltd
Priority date: 2022-09-30
Filing date: 2023-05-17
Publication date: 2024-05-22
Also published as: CN115377657A; WO2024066393A1; EP4372911A4; MX2023013667A

Abstract

The present application provides a low-frequency filtering radiating element and a base station antenna, where the low-frequency filtering radiating element includes: a substrate, which includes a first mounting surface and a second mounting surface arranged opposite; and a low-frequency radiating element, which includes four pairs of dipoles distributed on the substrate centrosymmetrically, where the four pairs of dipoles are distributed in orthogonal polarization to form two groups of ±45° polarized radiating elements, each pair of dipoles includes two radiation arms arranged on the first mounting surface and the second mounting surface respectively, and the two radiation arms are arranged in a mirror mode.

Description

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Chinese Patent Application No. 2022112168258, filed on September 30, 2022 , entitled "Low-frequency Filtering Radiating Element and Base Station Antenna", which is hereby incorporated by reference in its entirety.

FIELD

The present application relates to the field of communication equipment, and in particular to a low-frequency filtering radiating element and a base station antenna.

BACKGROUND

A radiating element is a main part of an antenna and can transmit and receive electromagnetic waves directionally to realize wireless communication. A dual-polarized radiating element can realize polarity diversity, and can work in a transceiver duplex mode, which greatly reduces a number of antennas and occupation space. The integration of a multi-band antenna in the industry is getting higher, and radiating elements with different frequency bands need to be arranged in a limited space. Traditional high-frequency and low-frequency integration schemes include a low-frequency bowl-shaped nested scheme and a crossed radiating element scheme. Although the low-frequency bowl-shaped nested scheme has a better performance, it has a fixed formation of the arrays, and although the crossed radiating element scheme has a flexible formation of the arrays, it has a poor index. Therefore, it is an urgent problem for those skilled in the art to design a low-frequency radiating element with simple structure, excellent performance and little influence on high frequencies.

SUMMARY

An embodiment of the present application provides a low-frequency filtering radiating element, including:

a substrate, including a first mounting surface and a second mounting surface arranged opposite; and
a low-frequency radiating element, including four pairs of dipoles distributed on the substrate centrosymmetrically, where the four pairs of dipoles are distributed in orthogonal polarization to form two groups of ±45° polarized radiating elements, each pair of dipoles includes two radiation arms arranged on the first mounting surface and the second mounting surface respectively, and the two radiation arms are arranged in a mirror mode.

According to the low-frequency filtering radiating element provided by the present application, each of the first mounting surface and the second mounting surface is provided with a fed element respectively, the fed element includes four orthogonally distributed feeder baluns, and each of the feeder baluns is connected to a corresponding radiation arm, two feeder baluns on a same extension line in each fed element are cascaded at a center of the substrate.
According to the low-frequency filtering radiating element provided by the present application, each of the feeder baluns is provided with at least one filtering stub, and the filtering stub is used to reduce the affect of the low-frequency radiating element on the high-frequency oscillator.
According to the low-frequency filtering radiating element provided by the present application, the filtering stubs form multiple filtering stub groups, the multiple filtering stub groups are sequentially distributed at intervals along a length direction of a corresponding feeder balun, and two filtering stubs of each filtering stub group are symmetrically distributed on both sides at intervals along the length direction of the corresponding feeder balun.
According to the low-frequency filtering radiating element provided by the present application, each of the filtering stubs is linear, curved or L-shaped.
According to the low-frequency filtering radiating element provided by the present application, each of the radiation arms includes multiple filtering members and inductive stubs connected to the filtering members.
According to the low-frequency filtering radiating element provided by the present application, the low-frequency filtering radiating element further includes a support seat, where the support seat includes a base and two feeder substrates located on the base, and the two feeder substrates are orthogonally distributed and connected to the fed element on the second mounting surface.
According to the low-frequency filtering radiating element provided by the present application, an inside of each of the feeder baluns is provided with a feeder circuit, and the feeder circuit is used to feed a corresponding radiation arm through a coaxial line and/or a feeder pad.
The present application further provides a base station antenna, including:

a pedestal;
a high-frequency radiating element, including multiple high-frequency oscillators located on the pedestal; and
multiple low-frequency filtering radiating elements as mentioned above, which are distributed at intervals between the high-frequency oscillators.

According to the base station antenna provided by the present application, a spacing of the high-frequency oscillators is 0.7 λ~0.9 λ.

BRIEF DESCRIPTION OF DRAWINGS

In order to clearly illustrate the solutions of the embodiments according to the present application, the accompanying drawings used in the description of the embodiments are briefly introduced below. It should be noted that the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings may be obtained according to these drawings without creative effort.

FIG. 1 is a three-dimensional schematic structural diagram of a low-frequency filtering radiating element according to an embodiment of the present application;
FIG. 2 is a schematic structural diagram of a front side of a substrate in FIG. 1;
FIG. 3 is a schematic structural diagram of a rear side of the substrate in FIG. 1;
FIG. 4 is a three-dimensional schematic structural diagram of a base station antenna according to an embodiment of the present application;

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to make the objectives, solutions and advantages of the present application clearer, the solutions of the embodiments of the present application are clearly and completely described below in combination with the accompanying drawings of the embodiments of the present application. The described embodiments are a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of the protection of the present application.
In the embodiments of the present application, it should be noted that the orientations or positional relationships indicated by terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and so on are based on the orientations or positional relationships shown in the drawings, which are only for convenience and simplifying of describing the embodiments of the present application, and do not indicate or imply that the apparatus or element referred to must have a specific orientation, or be construct or operate in a specific orientation, and therefore should not be construed as limits of the embodiments of the present application. In addition, the terms "first", "second", and "third" are used for descriptive purpose only, and should not be construed as indicating or implying relative importance.
In the embodiments of the present application, it should be noted that unless otherwise specified and limited, the terms "connected" and "joined" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection or integrated connection; it can be mechanical connection or electrical connection; or it can be direct connection or indirect connection through an intermediary. Those of ordinary skill in the art may understand the specific meanings of the above terms in the embodiments of the present application in specific situations.
In the embodiments of the present application, unless otherwise specified and limited, a first feature being "above" or "below" a second feature may mean that the first feature and the second feature are in direct contact, or the first feature and the second feature are in indirect contact through an intermediary. Moreover, the first feature being "above", "upward" or "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or only mean that a horizontal height of the first feature is higher than a horizontal height of the second feature. The first feature being "below", "downward" or "beneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or only mean that a horizontal height of the first feature is lower than a horizontal height of the second feature.
In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and so on mean that specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in suitable manners in any one or multiple embodiments or examples. In addition, those skilled in the art may combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.
A low-frequency filtering radiating element 100 and a base station antenna 10 according to the present application are described below with reference to FIG. 1 to FIG. 4.
In a traditional multi-band integrated antenna, a low-frequency radiating element is relatively large in size compared to a high-frequency radiating element, which always deteriorates high-frequency indicators in multi-band integrated systems. The present application provides a low-frequency filtering radiating element 100, including: a substrate 110, which includes a first mounting surface 111 and a second mounting surface 112 arranged opposite; a low-frequency radiating element 120, which includes four pairs of dipoles 121 distributed on the substrate 110 centrosymmetrically, where the four pairs of dipoles 121 are distributed in orthogonal polarization to form two groups of ±45° polarized radiating elements, each pair of dipoles 121 includes two radiation arms 122 arranged on the first mounting surface 111 and the second mounting surface 112 respectively, and the two radiation arms 122 are arranged in a mirror mode.
The low-frequency filtering radiating element 100 constitutes a fundamental structure of an antenna, and can effectively radiate or receive radio waves. The low-frequency filtering radiating element 100 may be made of materials as required, such as a printed circuit board (PCB) or a metal die-cast plate. In an example, the substrate 110 is the PCB or the metal die-cast plate correspondingly. A dielectric thickness, a dielectric constant and related parameters of the substrate 110 may be set according to actual requirements, for example, a range of the dielectric thickness of the substrate 110 is 0.2 mm to 3 mm, and a range of the dielectric constant is 2 to 10.
The low-frequency filtering radiating element 100 according to the present application, includes two groups of ±45° polarized radiating elements, where the radiating element consisted of two dipoles 121 not only has better element radiation performance than a common single dipole 121 crossed antenna, array performance is also more stable; and compared to a bowl-shaped radiating element, the low-frequency filtering radiating element 100 according to the present application has higher integration, smaller installation area, more flexible array and may significantly improve the applicability of the radiating element.
In an embodiment, each of the first mounting surface 111 and the second mounting surface 112 is provided with a fed element 130 respectively, the fed element 130 includes four orthogonally distributed feeder baluns 131, and each of the feeder baluns 131 is connected to a corresponding radiation arm 122, two feeder baluns 131 on a same extension line in each fed element 130 are cascaded at the center of the substrate 110 to make the two dipoles 121 on the same extension line form a ±45° polarized radiating element. Further, each of the feeder baluns 131 is provided with at least one filtering stub 132, and the filtering stub 132 is used to reduce the affect of the low-frequency radiating element 120 on the high-frequency oscillator. It should be noted that the number and shape of the filtering stubs 132 may be set according to actual requirements, for example, the filtering stubs 132 may be set as the same or different shapes, different lengths and different widths, and the filtering stubs 132 may be linear, curved or L-shaped, which is not specifically limited in this embodiment. In this embodiment, the filtering stubs 132 form multiple filtering stub groups, the multiple filtering stub groups are sequentially distributed at intervals along the length direction of the corresponding feeder balun 131, and two filtering stubs 132 of each filtering stub group are symmetrically distributed on both sides at intervals along the length direction of the corresponding feeder balun 131, and the filtering stubs 132 are L-shaped.
In the related art, decoupling between radiating elements of different frequency bands is mainly achieved in the feeder network, by the form of circuits, and by filter manners such as adding isolation strips, barriers, elements or PCBs between radiating elements of different frequency bands, to reduce a coupling between the radiating elements of different frequency bands as much as possible. However, this manner needs to add a large number of filtering elements between the radiating elements, which occupies a lot of space, results in a small space occupation of the radiating elements on the antenna, affects the overall layout of the radiating elements on the antenna, and makes it harder for the antenna as a whole to meet the requirement of the number of frequency bands, or the effect of eliminating interference cannot meet the expected requirements. In the present application, in an embodiment, each radiation arm 122 includes multiple filtering members 123 and inductive stubs 124 connected to the filtering members 123. By adding filtering members 123 in the radiation arm 122, filtering effect is achieved, which causes the radiation arm 122 to have a certain filtering effect on interference from other frequency bands, to avoid changing the arrangement of the radiation arms 122 on the antenna and occupying extra space of the antenna.
It should be noted that the number and shape of the filtering member 123 of each radiation arm 122 may be set according to actual requirement, for example, the filtering members 123 may be set as the same or different shapes, different lengths and different widths, and the filtering members 123 are connected by inductive stubs 124, which is not specifically limited in this embodiment. In this embodiment, the radiation arm 122 is configured as rectangular in shape, the filtering member 123 is correspondingly configured as rectangular in shape and the inductive stub 124 is configured as strip in shape and used for connecting the filtering members 123.
In an embodiment, the low-frequency filtering radiating element 100 also includes a support seat 140, which includes a base 142 and two feeder substrates 141 located on the base 142. The two feeder substrates 141 are orthogonally distributed and connected to the fed element 130 on the second mounting surface 112, and are used to feed the feeder baluns 131. The feeder substrate 141 may be PCB or metal die-cast plates, which is not limited in the present application. In an embodiment, a feeder circuit is provided inside the feeder balun 131, and the feeder circuit is used to feed a corresponding radiation arm 122 through a coaxial line and/or a feeder pad.
Based on the aforementioned low-frequency filtering radiating element 100, the present application also provides a base station antenna 10, including: a pedestal 200; a high-frequency radiating element 300, which includes multiple high-frequency oscillators 310 located on the pedestal 200; and low-frequency filtering radiating elements 100, which are distributed at intervals between the high-frequency oscillators 310. The spacing of the high-frequency oscillators is 0.7 λ~0.9 λ. Since the main improvement of the present application is in the low-frequency filtering radiating element 100, the detailed structure of the base station antenna 10 is not further described.
It should be noted that the above embodiments are merely used to illustrate the solutions of the present application, rather than limiting the solutions. Although the present application has been described in detail with reference to the foregoing embodiments, it should be noted that the solutions recited in the foregoing embodiments may be modified, or some of the features recited in the foregoing embodiments may be substituted equivalently, and these modifications or substitutions do not make the nature of the corresponding solutions separate from the scope of the solutions of the embodiments of the present application.

Claims

A low-frequency filtering radiating element, comprising:
a substrate, comprising a first mounting surface and a second mounting surface arranged opposite; and

a low-frequency radiating element, comprising four pairs of dipoles distributed on the substrate centrosymmetrically, wherein the four pairs of dipoles are distributed in orthogonal polarization to form two groups of ±45° polarized radiating elements, each pair of dipoles comprises two radiation arms arranged on the first mounting surface and the second mounting surface respectively, and the two radiation arms are arranged in a mirror mode.
The low-frequency filtering radiating element of claim 1, wherein each of the first mounting surface and the second mounting surface is provided with a fed element, the fed element comprises four orthogonally distributed feeder baluns, and each of the feeder baluns is connected to a corresponding radiation arm, two feeder baluns on a same extension line in each fed element are cascaded at a center of the substrate.
The low-frequency filtering radiating element of claim 2, wherein each of the feeder baluns is provided with at least one filtering stub.
The low-frequency filtering radiating element of claim 3, wherein the filtering stubs form multiple filtering stub groups, the multiple filtering stub groups are sequentially distributed at intervals along a length direction of a corresponding feeder balun, and two filtering stubs of each filtering stub group are symmetrically distributed on both sides at intervals along the length direction of the corresponding feeder balun.
The low-frequency filtering radiating element of claim 4, wherein each of the filtering stubs is linear, curved or L-shaped.
The low-frequency filtering radiating element of claim 2, wherein each of the radiation arms comprises multiple filtering members and inductive stubs connected to the filtering members.
The low-frequency filtering radiating element of claim 2, further comprising a support seat, including a base and two feeder substrates located on the base, and the two feeder substrates are orthogonally distributed and connected to the fed element on the second mounting surface.
The low-frequency filtering radiating element of claim 2, wherein an inside of each of the feeder baluns is provided with a feeder circuit, and the feeder circuit is used to feed a corresponding radiation arm through a coaxial line and/or a feeder pad.
A base station antenna, comprising:
a pedestal;

a high-frequency radiating element, including multiple high-frequency oscillators located on the pedestal; and

multiple low-frequency filtering radiating elements of any one of claims 1 to 8, which are distributed at intervals between the high-frequency oscillators.
The base station antenna of claim 9, wherein a spacing of the high-frequency oscillators is 0.7 λ~0.9 λ.