Structural multiplexing low-frequency oscillator and coaxial nested base station antenna

Abstract

The present invention discloses a structural multiplexing type low-frequency oscillator, including a base, a bowl-shaped oscillating arm and a plurality of feeding coaxial lines, wherein the bowl-shaped oscillating arm is arranged above the base and is surrounded by a plurality of oscillating arm units, each oscillating arm unit includes an oscillating arm main body and an oscillating arm bending part, the oscillating arm main body includes a bottom and a side wall, the oscillating arm bending part is arranged above the side wall, the bottoms of the plurality of oscillating arm main bodies form a high-frequency reflection plate when high and low frequencies are coaxially nested in the same plane, and the feeding coaxial line is connected to the feeding port on the bottom of the oscillating arm main body. The present invention widens the oscillator arm into a full metal surface structure, increases the metal area of ​​the oscillating arm and the coupling degree between the oscillating arms, thereby effectively increasing the working bandwidth of the antenna while reducing the size of the antenna; the bottom of the oscillating arm after two bends is a planar structure, which can be reused as the reflection ground structure required by the high-frequency antenna when the high-frequency antenna is coaxially embedded, thereby effectively eliminating the high-frequency reflection plate that was originally required extra, and simplifying the overall structure of the antenna.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave and millimeter wave communications, and in particular to a structural multiplexing type low-frequency vibrator and a coaxial nested base station antenna comprising the structural multiplexing type low-frequency vibrator. Background Art

[0002] With the continuous development of 2G, 3G, 4G and 5G communication networks, the coexistence of multi-band and multi-standard systems has become the main feature of the development of modern wireless communication systems. Therefore, using multi-frequency antenna arrays as base station antennas allows the antenna array in a single antenna cover to work in multiple frequency bands and support multiple standard networks at the same time, which has incomparable advantages over single-band antennas.

[0003] At present, the design of multi-frequency antennas is mostly implemented by coaxially nesting low-frequency antennas and high-frequency antennas. In this implementation method, the high-frequency and low-frequency antennas share the same physical aperture, which has the advantages of small lateral size and compact structure. It is the research focus and difficulty in the field of antenna design. For example, in the coaxial nested antennas widely used in 4G mobile communication base stations, there are 900MHz low-frequency bowl-shaped antennas for 3G networks and 1800MHz high-frequency dipole antennas for 4G networks, in which the 1800MHz high-frequency dipole antenna is coaxially nested in the 900MHz low-frequency bowl-shaped antenna.

[0004] As China Broadcasting Corporation's 700MHz frequency band is officially included in my country's 5G commercial frequency band, the low-frequency band of 5G base station antennas needs to be expanded from the current 820MHz to 960MHz to 690MHz to 960MHz. The existing coaxial nested base station antenna solution is difficult to meet the following requirements: On the one hand, the low-frequency bowl-shaped antenna of the existing solution is often difficult to meet the small size (<145×145×80mm 3 ) and the bandwidth coverage requirements of 690MHz to 960MHz; on the other hand, when the high-frequency oscillator antenna is coaxially arranged in the low-frequency bowl-shaped antenna, an additional reflector is often required to achieve directional radiation of the high-frequency antenna, which will increase the structural complexity and processing and installation costs.

[0005] Based on this, a new solution is needed. Summary of the invention

[0006] The main purpose of the present invention is to provide a structural multiplexed low-frequency oscillator, which not only has a broadband performance covering 690MHz to 960MHz, but can also be coaxially integrated with a high-frequency antenna in a simple and compact manner.

[0007] To achieve the above-mentioned purpose, the present invention provides a structural multiplexed low-frequency vibrator, comprising a base, a bowl-shaped vibrating arm and multiple feeding coaxial lines, wherein the bowl-shaped vibrating arm is arranged above the base and is surrounded by multiple vibrating arm units, each vibrating arm unit comprises a vibrating arm main body and a vibrating arm bending part, the vibrating arm main body comprises a bottom and a side wall, the vibrating arm bending part is arranged above the side wall, the bottoms of multiple vibrating arm main bodies constitute a high-frequency reflection plate when high and low frequency coaxials are nested in the same plane, and the feeding coaxial line is connected to the feeding port on the bottom of the vibrating arm main body.

[0008] In the structural multiplexed low-frequency vibrator provided by the present invention, the vibrating arm main body portion and the vibrating arm bent portion are formed by bending the same metal plate.

[0009] In the structural multiplexing type low-frequency vibrator provided by the present invention, the bowl-shaped vibrating arm is a symmetrical structure.

[0010] In the structural multiplexing type low-frequency vibrator provided by the present invention, a loading gap portion is arranged between the bottoms of two adjacent vibrating arm main body portions.

[0011] In the structural multiplexing type low-frequency oscillator provided by the present invention, the loading slot portion includes a long slot and two short slots, and the two short slots are respectively arranged on both sides of the end of the long slot.

[0012] In the structural multiplexing type low-frequency vibrator provided by the present invention, the bowl-shaped vibrating arm is vertically arranged on the base.

[0013] In the structural multiplexed low-frequency vibrator provided by the present invention, the bending portion of the vibrating arm includes a first bending unit and a second bending unit, the first bending unit is connected to the side wall and is parallel to the bottom, and the second bending unit is connected to the first bending unit and folds and droops toward the bottom.

[0014] The structural multiplexed low-frequency vibrator provided by the present invention also includes a central opening arranged at the intersection of the plurality of vibrating arm main bodies.

[0015] The present invention also provides a coaxial nested base station antenna, comprising the structural multiplexing type low-frequency oscillator and high-frequency oscillator as described above.

[0016] The structural multiplexing type low-frequency oscillator provided by the present invention has the following beneficial effects:

[0017] 1. Small size and wide bandwidth: Traditional bowl-shaped antennas often use thin dipole arm structures to reduce the impact on coaxial embedded high-frequency antennas. The overall size is large and the bandwidth is narrow, making it difficult to fully cover the 690-960MHz frequency band. The present invention widens the dipole arm of the traditional bowl-shaped antenna into a full metal surface structure, increases the metal area of ​​the dipole arm and the coupling degree between the dipole arms, thereby effectively increasing the working bandwidth of the antenna while reducing the size of the antenna;

[0018] 2. Simple and stable structure: In the traditional high- and low-frequency coaxial nested design, the high-frequency antenna is often required to be raised to reduce the mutual coupling between the high- and low-frequency designs. In order to obtain good directional radiation performance, the high-frequency antenna needs to introduce additional metal reflector components, which not only increases the structural complexity and processing and installation costs, but also reduces the stability of the antenna's structure and electrical performance. The present invention abandons the traditional linear boom structure and bends the boom twice. The bottom of the boom after the two bends is a planar structure, which can be reused as the reflective ground structure required for the high-frequency antenna when the high-frequency antenna is coaxially embedded, thereby effectively eliminating the original additional high-frequency reflector and simplifying the overall structure of the antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below. Obviously, the drawings in the following description are only embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without creative work:

[0020] Figure 1 The figure shows a front view of a structural multiplexing type low-frequency oscillator provided by an embodiment of the present invention;

[0021] Figure 2 The figure shows a side view of a structural multiplexing type low-frequency oscillator provided by an embodiment of the present invention;

[0022] Figure 3 The figure shows a top view of a structural multiplexing type low-frequency oscillator provided by an embodiment of the present invention;

[0023] Figure 4 Shown is a schematic diagram of a coaxial nested base station antenna provided by an embodiment of the present invention;

[0024] Figure 5 Shown is the reflection coefficient of the antenna in the simulation experiment;

[0025] Figure 6 Shown is the port-to-port isolation performance for dual-polarization antennas;

[0026] Figure 7 and 8 The radiation patterns of the antenna at three frequencies are given. DETAILED DESCRIPTION

[0027] In order to facilitate understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Typical embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0029] The disadvantages of the bowl-mounted low-frequency vibrator in the prior art mainly include the following three points:

[0030] The first point is that the bandwidth is narrow. In the 4G era, the bandwidth that low-frequency bowl-shaped antennas need to cover is usually 820MHz to 960MHz. In today's 5G era, considering the participation of China Radio and Television, the bandwidth that bowl-shaped antennas need to cover is expanded to 690MHz to 960MHz.

[0031] The second point is that the size is too large. In order to maintain the corresponding gain, the antenna aperture (and electrical size) needs to be maintained at a certain size, but as the antenna bandwidth expands to low frequencies, the center frequency of the antenna decreases, and the equivalent antenna electrical size will be further reduced. In order to obtain sufficient gain at low frequencies, the antenna aperture needs to be increased, but too large a size will affect other performances such as front-to-back ratio and isolation.

[0032] The third point is the complex structure. In the existing high- and low-frequency coaxial nesting technology, the high-frequency oscillator antenna usually requires an additional reflector to achieve directional radiation. This will not only increase the structural complexity and processing and installation costs, but also reduce the stability of the antenna's structure and electrical performance.

[0033] Based on this, the present invention provides a structural multiplexing type low-frequency vibrator, which can not only expand the antenna bandwidth and maintain the radiation performance in a smaller size, but also save the additional high-frequency reflector structure when the high and low frequencies are coaxially nested. First, the vibrator arm of the traditional bowl-shaped antenna is widened to a full metal surface structure, which increases the metal area of ​​the vibrating arm and the coupling degree between the vibrating arms, thereby effectively increasing the working bandwidth of the antenna while reducing the size of the antenna. On this basis, the traditional linear vibrating arm structure is abandoned, and the vibrating arm is bent twice. The bottom of the vibrating arm after the two bends is a planar structure, which can be reused as the reflection ground structure required by the high-frequency antenna when the high-frequency antenna is coaxially embedded, thereby effectively saving the high-frequency reflector that was originally required, and simplifying the overall structure of the antenna. Although the twice-bent structure has the above advantages, the planar structure at the bottom of the vibrating arm will cause the capacitive reactance of the antenna input impedance to increase, which is not conducive to the impedance matching of the antenna. Therefore, the present invention introduces a slot loading at the bottom of the vibrating arm of the antenna to increase the inductive reactance of the antenna, which offsets the capacitive reactance and achieves impedance matching of the antenna. The structural multiplexing broadband bowl-shaped oscillator proposed in the present invention fully considers the efficient integration with the high-frequency antenna, has a simple structure and is easy to assemble. Its bandwidth can cover the 700MHz frequency band of China Broadcasting and Television in 5G and the conventional 900MHz frequency band of LTE (690-960MHz).

[0034] In order to better understand the above-mentioned technical scheme, the above-mentioned technical scheme will be described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical scheme of the present application, rather than limitations on the technical scheme of the present application. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other.

[0035] Embodiment 1

[0036] Figure 1 The figure shows a front view of a structural multiplexing type low-frequency oscillator provided by an embodiment of the present invention; Figure 2 The figure shows a side view of a structural multiplexing type low-frequency oscillator provided by an embodiment of the present invention; Figure 3 FIG. 1 is a top view of a structural multiplexing type low-frequency oscillator provided by an embodiment of the present invention. Figure 1-3 As shown, the structural multiplexing type low-frequency vibrator provided by the present invention comprises a base 1, a bowl-shaped vibrating arm and a plurality of feeding coaxial lines (4-1, 4-1', 4-2, 4-2'), wherein the bowl-shaped vibrating arm is arranged above the base.

[0037] Specifically, in one embodiment of the present invention, the bowl-shaped arm is composed of a plurality of arm units (for example, Figure 1The embodiment shown includes 4 arm units) surrounded by each arm unit, each arm unit includes an arm body portion 2 and an arm bending portion 3, the arm body portion includes a bottom and a side wall, the arm bending portion is arranged above the side wall, and the bottoms of the multiple arm body portions constitute a high-frequency reflection plate when the high and low frequencies are coaxially nested in the same plane. The multiple bottoms of the multiple arm body portions 2 constitute the planar metal ground at the bottom of the bowl-shaped antenna, and the multiple side walls constitute the surrounding metal wall structure. The planar metal ground can be reused as the reflection ground structure required by the high-frequency antenna when the high-frequency antenna is coaxially embedded, thereby effectively eliminating the high-frequency reflection plate that is originally required extra and simplifying the overall structure of the antenna.

[0038] Furthermore, in one embodiment of the present invention, the bowl-shaped boom is vertically arranged on the base, and the feeding coaxial line is connected to the feeding port on the bottom of the boom body. In the present invention, the square base is used to support the remaining structures and provide a stable grounding connection, and the feeding coaxial line is connected to the feeding port of the boom body via the coaxial line connection hole on the bottom of the boom body along the side wall of the square base to provide feeding.

[0039] Furthermore, in one embodiment of the present invention, the bowl-shaped boom is a symmetrical structure, and the boom main body and the boom bending portion are formed by bending the same metal plate. As a result, the boom arm of the traditional bowl-shaped antenna is widened to a full metal surface structure, increasing the metal area of ​​the boom and the coupling between the booms, thereby effectively increasing the working bandwidth of the antenna while reducing the size of the antenna.

[0040] Furthermore, the swing arm bending portion 3 includes a first bending unit and a second bending unit, the first bending unit is connected to the side wall and is parallel to the bottom, and the second bending unit is connected to the first bending unit and folded and drooped in the direction of the bottom. In the present invention, the planar size of the antenna can be further reduced by folding and drooping the swing arm bending portion. Thus, firstly, the same metal plate is bent to form the swing arm main body and the swing arm bending portion, thereby increasing the swing arm width and the coupling degree between the swing arms, thereby increasing the working bandwidth of the antenna while reducing the size of the antenna. On this basis, the traditional linear structure is abandoned, and the bottom of the swing arm after the second bending is a planar structure, which can be reused as the reflection ground structure required by the high-frequency antenna when the high-frequency antenna is coaxially embedded, thereby effectively eliminating the high-frequency reflection plate that was originally required extra, and simplifying the overall structure of the antenna.

[0041] Furthermore, in one embodiment of the present invention, a loading slot portion 6 is provided between the bottoms of two adjacent boom main bodies. The loading slot portion includes a long slot and two short slots, and the two short slots are respectively provided on both sides of the end of the long slot, wherein the end of the long slot is an end of the long slot close to the center of the plane formed by the bottoms of the multiple boom main bodies. Furthermore, the middle long slot provides the phase required for feeding, and the two extended short slots provide inductive loading for the antenna to increase the inductive reactance of the antenna. Due to the planar structure of the bottom of the boom main body formed by two bends, the capacitive reactance of the antenna input impedance will increase, which is not conducive to the impedance matching of the antenna. Therefore, the present invention introduces slot loading in the plane formed at the bottom of the boom main body of the antenna to increase the inductive reactance of the antenna, offset the capacitive reactance, and achieve impedance matching of the antenna.

[0042] Furthermore, in one embodiment of the present invention, a central opening 5 is provided at the intersection of the plurality of arm main bodies. When the high-frequency vibrator is used to form a coaxially nested base station antenna, the high-frequency vibrator is assembled with the low-frequency vibrator through the central opening 5, and can be designed as required according to the coaxially embedded high-frequency vibrator fixing member without special requirements.

[0043] The structural multiplexing type low-frequency oscillator provided by the present invention has the following advantages:

[0044] 1. Small size and wide bandwidth: In order to reduce the impact on the coaxial embedded high-frequency antenna, traditional bowl-shaped antennas often use a thin dipole arm structure, with a large overall size and a narrow bandwidth, making it difficult to fully cover the 690-960MHz frequency band; the present invention widens the dipole arm of the traditional bowl-shaped antenna into a full metal surface structure, increases the metal area of ​​the dipole arm and the coupling degree between the dipole arms, thereby effectively increasing the working bandwidth of the antenna while reducing the size of the antenna, and is achieved as a whole by open mold die casting; the overall height of the antenna is 78mm, and the plane size is 144mm×144mm.

[0045] 2. Simple and stable structure: In the traditional high- and low-frequency coaxial nested design, the high-frequency antenna is often required to be raised to reduce the mutual coupling between the high- and low-frequency designs. In order to obtain good directional radiation performance, the high-frequency antenna needs to introduce additional metal reflector components, which not only increases the structural complexity and processing and installation costs, but also reduces the stability of the antenna's structure and electrical performance. The present invention abandons the traditional linear boom structure and bends the boom twice. The bottom of the boom after the two bends is a planar structure, which can be reused as the reflective ground structure required for the high-frequency antenna when the high-frequency antenna is coaxially embedded, thereby effectively eliminating the original additional high-frequency reflector and simplifying the overall structure of the antenna.

[0046] Embodiment 2

[0047] Figure 4 FIG. 1 is a schematic diagram of a coaxial nested base station antenna provided by an embodiment of the present invention. Figure 4 As shown, the coaxial nested base station antenna provided in this embodiment Figure 1-3 The structure shown in the multiplexed low-frequency vibrator and high-frequency vibrator. When forming a coaxial nested base station antenna with the high-frequency vibrator, the high-frequency vibrator is assembled with the low-frequency vibrator through the central opening 5. Since the traditional linear vibrating arm structure is abandoned, the vibrating arm is bent twice, and the bottom of the vibrating arm after the two bends is a flat structure. When the high-frequency antenna is coaxially embedded, it can be reused as the reflection ground structure required by the high-frequency antenna, thereby effectively eliminating the high-frequency reflection plate that was originally required, and simplifying the overall structure of the antenna.

[0048] A simulation experiment was carried out according to the low-frequency vibrator and antenna provided by the present invention, wherein the radiation performance of the antenna is shown in Table 1. The size of the reflector is 300mm×300mm, and there is no side baffle. Furthermore, in actual use, a double-row array structure with side baffles will be adopted. The radiation performance requirement for a single unit is more focused on whether the half-width (3dB lobe width) of the antenna is stable. Table 1 can confirm that the half-width of the antenna is relatively stable. Figure 5 The reflection coefficient of the antenna is given, and its dual-polarization port isolation performance is as follows: Figure 6 As shown, the standing wave ratio is less than 1.25 (S11 is about -15), the bandwidth range is 680-965MHz, and it can well cover the 700\900 frequency band. (The above results are all computer simulation results); Figure 7 and 8 The radiation patterns of the antenna at three frequencies are given.

[0049] Table 1: Antenna radiation performance table

[0050]

[0051] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0052] Similarly, it should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this disclosed method should not be interpreted as reflecting the intention that the claimed invention requires more features than those explicitly recited in each claim. More specifically, as reflected in the claims below, inventive aspects lie in less than all the features of the individual embodiments disclosed above. Therefore, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, with each claim itself serving as a separate embodiment of the present invention.

[0053] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present invention and form different embodiments. For example, in the claims below, any one of the claimed embodiments may be used in any combination.

[0054] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising a number of different elements and by means of a suitably programmed computer. In a unit claim enumerating a number of devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc., does not indicate any order. These words may be interpreted as names.

Claims

1. A structural multiplexing low-frequency oscillator, characterized in that: It comprises a base, a bowl-shaped arm and a plurality of feeding coaxial lines, wherein the bowl-shaped arm is arranged above the base and is surrounded by a plurality of arm units, each arm unit comprises an arm body and an arm bending part, the arm body comprises a bottom and a side wall, the arm bending part is arranged above the side wall, the bottoms of the plurality of arm bodies form a high-frequency reflection plate when high and low frequency coaxials are nested in the same plane, and the feeding coaxial line is connected to a feeding port on the bottom of the arm body; The arm main body and the arm bending portion are formed by bending the same metal plate; The swing arm bending portion includes a first bending unit and a second bending unit, the first bending unit is connected to the side wall and parallel to the bottom, and the second bending unit is connected to the first bending unit and folded and drooped toward the bottom.

2. The structural multiplexing type low frequency oscillator according to claim 1, characterized in that: The bowl-shaped vibration arm is a symmetrical structure.

3. The structural multiplexing type low frequency oscillator according to claim 1, characterized in that: A loading gap portion is arranged between the bottoms of two adjacent vibration arm main body portions.

4. The structural multiplexing type low frequency oscillator as claimed in claim 3, characterized in that: The loading gap portion includes a long gap and two short gaps, and the two short gaps are respectively arranged on both sides of the end of the long gap.

5. The structural multiplexing type low frequency oscillator as claimed in claim 1, characterized in that: The bowl-shaped vibration arm is vertically arranged on the base.

6. The structural multiplexing type low-frequency oscillator according to claim 1, characterized in that: It also includes a central opening arranged at the intersection of the plurality of vibration arm main body parts.

7. A coaxial nested base station antenna, characterized in that: It comprises a structurally multiplexed low-frequency oscillator and a high-frequency oscillator as described in any one of claims 1 to 6.

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