An omnidirectional circularly polarized antenna

Abstract

An omnidirectional circularly polarized antenna, relating to the field of communication antenna technology, includes a support, multi-layer coupled radiating arms, parasitic decoupling posts, a broadband feed network, and feed lines. The support is constructed from a molded substrate, comprising a one-piece molded ground plane and antenna body, with a diameter ≤18mm and a height ≤16mm, achieving miniaturization. The multi-layer coupled radiating arms include a main radiating arm and parasitic radiating arms, with bandwidth and circular polarization characteristics adjusted by the coupling spacing. The parasitic decoupling posts are located at the center of the support, improving ultra-wideband impedance matching and compressing size. The broadband feed network employs a three-branch balun structure etched onto the support surface, achieving impedance gradient through U-shaped feed branches with connection end linewidths smaller than free end linewidths, ensuring conformal radiation pattern preservation. The feed lines are soldered to the broadband feed network for signal transmission. The main radiating arms, parasitic radiating arms, and broadband feed network are all etched onto the support surface using laser engraving technology, simplifying manufacturing.

Description

Technical Field

[0001] This utility model relates to the field of communication antenna technology, specifically an omnidirectional circularly polarized antenna suitable for wireless communication systems of smart devices (such as drones and smart home terminals). Background Technology

[0002] With the continuous development of mobile communication technology, antennas have become an indispensable key component in modern smart devices. The performance of an antenna directly affects the device's performance and user experience. With the vigorous development of 5G communication, smart homes, smart industrial equipment, autonomous driving, and long-range unmanned image transmission devices all heavily rely on antenna systems. Good antenna design often determines a product's competitiveness, thus placing high demands on the antenna design of smart devices.

[0003] Traditional ultrawideband circularly polarized antennas mainly employ a double-arm helical structure, extending bandwidth by increasing the number of helical turns, but this has the following drawbacks:

[0004] Too large: Multiple turns of winding are required to achieve ultra-wide width, making it difficult to integrate into small devices;

[0005] Poor omnidirectionality: The radiation pattern is an inverted figure-eight shape, not true omnidirectional, and the signal coverage is uneven;

[0006] Complex assembly: The use of PCB or sheet metal processes requires welding of multiple parts, resulting in poor consistency and low yield.

[0007] Unstable circular polarization performance: The axial ratio is prone to deterioration in the ultra-wideband range, affecting the anti-interference capability. Utility Model Content

[0008] (a) Technical problems to be solved

[0009] To address the above issues, this invention provides an omnidirectional circularly polarized antenna that achieves ultra-wideband and stable circular polarization characteristics within a miniaturized size; it eliminates the inverted figure-eight radiation of traditional antennas, achieving true omnidirectional coverage; and it simplifies the manufacturing process, avoiding performance fluctuations caused by the assembly of multiple components.

[0010] (II) Technical Solution

[0011] To achieve the above objectives, this utility model provides the following technical solution:

[0012] An omnidirectional circularly polarized antenna, comprising:

[0013] The bracket is made of a molded substrate and includes a floor and an antenna body, wherein the floor and the antenna body are integrally formed.

[0014] A multi-layer coupled radiation arm is disposed on the support and includes a main radiation arm and a parasitic radiation arm. The main radiation arm and the parasitic radiation arm adjust the bandwidth and circular polarization characteristics through the coupling spacing.

[0015] Parasitic decoupling post, which is disposed at the center of the bracket, is used to improve ultra-wideband impedance matching and reduce antenna size;

[0016] A broadband feed network, which adopts a three-branch balun structure and is etched into the bracket, and is coaxially arranged with the parasitic decoupling post, is used to achieve broadband impedance matching and radiation pattern conformal preservation.

[0017] A feeder line, which is connected to the broadband power supply network, is used for signal transmission.

[0018] Preferably, the diameter of the bracket is ≤18mm and the height is ≤16mm.

[0019] Preferably, both the main radiating arm and the parasitic radiating arm are helical structures, with the upper part of both extending upward along the right-hand thread direction and the lower part extending downward along the left-hand thread direction.

[0020] Preferably, the parasitic decoupling column and the support are integrally formed by a mold-making process.

[0021] Preferably, the parasitic decoupling column is an independent metal column and is welded to the center of the support.

[0022] Preferably, the three-branch balun structure of the broadband feeder network includes three feeder branches arranged in a circular array. The feeder branches are basically U-shaped. The open side of the feeder branches has a connection end and a free end. The connection ends of the three feeder branches are interconnected with the feeder line. The line width on the connection end side of each feeder branch is smaller than the line width on the free end side of the feeder branch, so as to achieve continuous impedance variation.

[0023] Preferably, the main radiating arm, the parasitic radiating arm, and the broadband power supply network are all etched onto the surface of the bracket using a laser engraving process.

[0024] Preferably, the feeder uses RG402 cable and is soldered to the broadband power supply network for signal connection.

[0025] Preferably, the omnidirectional circularly polarized antenna has an operating bandwidth of 4.8-6.2 GHz and a standing wave ratio (VSWR) of <1.6.

[0026] Preferably, it further includes an antenna radome covering the exterior of the bracket, the multilayer coupled radiating arm, the parasitic decoupling post, and the broadband feed network.

[0027] (III) Beneficial Effects

[0028] Compared with the prior art, the beneficial effects of this utility model are:

[0029] Ultra-wideband and circular polarization optimization: operating bandwidth 4.8-6.2GHz, VSWR <1.6; decoupling pillars suppress high-frequency mismatch, and multi-layer radiating arms extend the circular polarization bandwidth.

[0030] True omnidirectional radiation: Three-branch feeding achieves a uniform omnidirectional radiation pattern (distinct from the inverted figure-eight pattern); the radiation pattern is shape preserved, and the gain fluctuation is smaller.

[0031] Miniaturization and low cost: The size is reduced to less than 18 (diameter) × 16 (height) mm, and the weight is reduced; the integrated bracket and laser engraving process reduce production costs and improve yield.

[0032] Ease of manufacturing: Eliminates the welding / assembly process (compared to traditional PCB / sheet metal processes). Attached Figure Description

[0033] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0034] Figure 1 A perspective view of the omnidirectional circularly polarized antenna of this invention is shown;

[0035] Figure 2 It shows Figure 1 A three-dimensional view of an omnidirectional circularly polarized antenna from another angle;

[0036] Figure 3 It shows Figure 1 A 3D view of an omnidirectional circularly polarized antenna after the radome has been removed;

[0037] Figure 4 It shows Figure 3 A 3D view from another angle;

[0038] Figure 5 It shows Figure 4 Enlarged view of part A in the image;

[0039] Figure 6 It shows Figure 3 Top view;

[0040] Figure 7 It shows Figure 3 A bottom view;

[0041] Figure 8 It shows Figure 1A three-dimensional view of a multilayer coupled radiating arm;

[0042] Figure 9 It shows Figure 1 A three-dimensional view of a parasitic decoupling column;

[0043] Figure 10 It shows Figure 1 A 3D diagram of a medium-bandwidth feeder network;

[0044] Figure 11 A schematic diagram showing the bandwidth and VSWR of the omnidirectional antenna of this invention is provided.

[0045] Figure 12 A schematic diagram showing the bandwidth and axial ratio of the omnidirectional antenna of this invention is provided.

[0046] Figure 13 A schematic diagram of the omnidirectional three-dimensional radiation direction of the omnidirectional antenna of this utility model is shown when the operating bandwidth is 4.8 GHz;

[0047] Figure 14 The diagram shows the main lobe direction and main lobe amplitude of the omnidirectional antenna of this invention when the operating bandwidth is 4.8 GHz.

[0048] In the diagram: 1. Support frame; 11. Floor; 12. Antenna body; 2. Multi-layer coupled radiating arm; 21. Main radiating arm; 22. Parasitic radiating arm; 3. Parasitic decoupling post; 4. Broadband feed network; 41. Feed branch; 411. Connection end; 412. Free end; 5. Feed line; 6. Radome. Detailed Implementation

[0049] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0050] See appendix Figure 1 -Appendix Figure 14This utility model discloses an omnidirectional circularly polarized antenna, comprising: a support 1, a multi-layer coupled radiating arm 2, a parasitic decoupling post 3, a broadband feed network 4, and a feed line 5. The support 1 is made of a molded substrate and includes a ground plane 11 and an antenna body 12, which are integrally formed. The multi-layer coupled radiating arm 2 is disposed on the support 1 and includes a main radiating arm 21 and a parasitic radiating arm 22. The parasitic decoupling post 3 is disposed at the center of the support 1. The broadband feed network 4 adopts a three-branch balun structure and is etched on the support 1, and is coaxially disposed with the parasitic decoupling post 3 to achieve broadband impedance matching and radiation pattern conformal. The feed line 5 is connected to the broadband feed network 4 for signal transmission.

[0051] Based on the above scheme, the bracket 1 is integrally molded from a molded substrate (such as plastic or composite material), with a compact structure that can be integrated into small devices without additional assembly (i.e., eliminating the separate assembly of the floor 11 and the antenna body 12), reducing labor time and errors, and improving product consistency and yield. The main radiating arm 21 and the parasitic radiating arm 22 adjust the bandwidth and circular polarization characteristics through the coupling spacing. The parasitic decoupling post 3 can improve ultra-wideband impedance matching and compress the antenna size. The broadband feed network 4 with a three-branch balun structure etched on the bracket 1 can achieve broadband impedance matching and conformal radiation pattern. The feed line 5 is used for signal transmission. In summary, by using this omnidirectional circularly polarized antenna, ultra-wideband and stable circular polarization characteristics can be achieved in a miniaturized size. It can eliminate the inverted figure-eight radiation of traditional antennas and achieve true omnidirectional coverage. It can simplify the manufacturing process and avoid performance fluctuations caused by the assembly of multiple components.

[0052] To ensure the miniaturization of the omnidirectional circularly polarized antenna, its size is limited in this embodiment. Specifically, the size of the bracket 1 is constrained to a diameter ≤ 18mm and a height ≤ 16mm.

[0053] Through the design of the above scheme, the maximum size of bracket 1 is no more than 18mm in diameter and 16mm in height. Through the integrated design, a low profile and miniaturization are achieved, which makes it easy to embed into smart devices and reduce weight.

[0054] See appendix Figure 3-5 and appendix Figure 8 and attached Figure 10 In order to optimize the axial ratio stability, the following design is made in this embodiment. Specifically, both the main radiating arm 21 and the parasitic radiating arm 22 are helical structures, and the upper parts of both the main radiating arm 21 and the parasitic radiating arm 22 extend upward along the right-hand thread direction, while the lower parts of both the main radiating arm 21 and the parasitic radiating arm 22 extend downward along the left-hand thread direction.

[0055] See appendix Figure 3 Appendix Figure 6 and attached Figure 9To avoid the risk of a single process for the parasitic decoupling column 3, this embodiment introduces two processes. Specifically, the first is that the parasitic decoupling column 3 and the support 1 are integrally formed by a mold-making process, which can reduce costs; the second is that the parasitic decoupling column 3 is an independent metal column and welded to the center of the support 1, and the precision can be controlled by separate welding. In addition, the above two processes can also expand the manufacturing compatibility of the parasitic decoupling column 3.

[0056] See appendix Figure 3 Appendix Figure 6 and attached Figure 10 To clarify the power supply network structure, the following design was implemented in this embodiment. Specifically, the three-branch balun structure of the broadband power supply network 4 includes three power supply branches 41 arranged in a circular array. The power supply branches 41 are basically U-shaped. The open side of the power supply branches 41 has a connection end 411 and a free end 412. The connection end 411 of the three power supply branches 41 is connected to the feed line 5. The line width on the side of the connection end 411 of each power supply branch 41 is smaller than the line width on the side of the free end 412 of the power supply branch 41 to achieve continuous impedance variation.

[0057] Based on the above scheme, the three-branch U-shaped balun can achieve impedance gradient, thereby ensuring omnidirectional phase consistency.

[0058] To address the consistency and cost issues of traditional processes (PCB / sheet metal), improve the consistency of the omnidirectional circularly polarized antenna, and reduce production costs, the following design was implemented in this embodiment: Specifically, the main radiating arm 21, the parasitic radiating arm 22, and the broadband feed network 4 are all etched onto the surface of the bracket 1 using laser engraving technology.

[0059] Based on the above solution, this application replaces the traditional welding process with laser engraving, which can achieve efficient production while ensuring accuracy, guaranteeing batch consistency of products, reducing welding steps, and lowering production costs.

[0060] See appendix Figure 1-4 To ensure reliable signal transmission and avoid compatibility issues with feeder 5, this embodiment limits the type and connection method of feeder 5. Specifically, feeder 5 uses RG402 cable and is soldered to the broadband power supply network 4 for signal connection.

[0061] By designing the above scheme, which involves using RG402 cable (standard high-frequency coaxial cable) to weld to the broadband feeder network 4, stable impedance matching can be provided, thereby optimizing the VSWR, reducing signal loss, and enhancing communication quality.

[0062] See appendix Figure 11 and attached Figure 12In order to clarify the ultra-wideband performance indicators and distinguish it from narrowband traditional antennas, through practical testing, the operating bandwidth of the omnidirectional circularly polarized antenna in this embodiment is 4.8-6.2GHz, and the VSWR is <1.6.

[0063] Based on the above scheme, actual measurement data proves that the omnidirectional circularly polarized antenna can expand bandwidth and support high data rate communication.

[0064] See appendix Figure 1 and attached Figure 2 Traditional designs are susceptible to environmental interference. To enhance the durability of the antenna, the following design is implemented in this embodiment. Specifically, it also includes an antenna radome 6, which covers the outside of the support 1, the multi-layer coupled radiating arm 2, the parasitic decoupling post 3, and the broadband feed network 4.

[0065] Through the above structural design, the radome 6 and the bracket 1 are integrated and packaged, which can cover and protect the internal structure, and achieve the effects of dust and water protection, improving adaptability to indoor and outdoor environments, and extending service life.

[0066] It should be noted that this application does not limit the shape, material, connection method, or other parameters of the radome 6. Therefore, it can be designed flexibly according to actual needs. For example, the radome 6 can be set as a cylinder and made of engineering plastic. In addition, the radome 6 can be sealed to the bracket 1 to enhance its protective performance.

[0067] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0068] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this application.

[0069] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An omnidirectional circularly polarized antenna, characterized in that, include: The bracket is made of a molded substrate and includes a floor and an antenna body, wherein the floor and the antenna body are integrally formed. A multi-layer coupled radiation arm is disposed on the support and includes a main radiation arm and a parasitic radiation arm. The main radiation arm and the parasitic radiation arm adjust the bandwidth and circular polarization characteristics through the coupling spacing. Parasitic decoupling post, which is disposed at the center of the bracket, is used to improve ultra-wideband impedance matching and reduce antenna size; A broadband feed network, which adopts a three-branch balun structure and is etched into the bracket, and is coaxially arranged with the parasitic decoupling post, is used to achieve broadband impedance matching and radiation pattern conformal preservation. A feeder line, which is connected to the broadband power supply network, is used for signal transmission.

2. The omnidirectional circularly polarized antenna according to claim 1, characterized in that, The diameter of the bracket is ≤18mm and the height is ≤16mm.

3. An omnidirectional circularly polarized antenna according to claim 1, characterized in that, Both the main radiating arm and the parasitic radiating arm are helical structures, with the upper part of both extending upward along the right-hand thread direction and the lower part extending downward along the left-hand thread direction.

4. An omnidirectional circularly polarized antenna according to claim 1, characterized in that, The parasitic decoupling column and the support are integrally formed through a mold-making process.

5. An omnidirectional circularly polarized antenna according to claim 1, characterized in that, The parasitic decoupling column is an independent metal column and is welded to the center of the support.

6. An omnidirectional circularly polarized antenna according to claim 1, characterized in that, The three-branch balun structure of the broadband feed network includes three feed branches arranged in a circular array. The feed branches are basically U-shaped. The open side of each feed branch has a connection end and a free end. The connection ends of the three feed branches are interconnected with the feed line. The line width on the connection end side of each feed branch is smaller than the line width on the free end side of the feed branch to achieve continuous impedance variation.

7. An omnidirectional circularly polarized antenna according to claim 1, characterized in that, The main radiating arm, the parasitic radiating arm, and the broadband power supply network are all etched onto the surface of the bracket using a laser engraving process.

8. An omnidirectional circularly polarized antenna according to claim 1, characterized in that, The feeder uses RG402 cable and is soldered to the broadband power supply network for signal connection.

9. An omnidirectional circularly polarized antenna according to claim 1, characterized in that, The omnidirectional circularly polarized antenna has an operating bandwidth of 4.8-6.2 GHz and a VSWR of <1.

6.

10. An omnidirectional circularly polarized antenna according to any one of claims 1-9, characterized in that, It also includes an antenna radome that covers the exterior of the bracket, the multilayer coupled radiating arm, the parasitic decoupling post, and the broadband feed network.

Images