An integrated omni-directional antenna and its digital key product

Abstract

The utility model discloses an integrated omnidirectional antenna and digital key product thereof, integrated omnidirectional antenna includes circuit board, first antenna module and second antenna module. First antenna module and second antenna module become a whole system, under the premise of isolation degree satisfaction, first parasitic branch as a part of environment, under the premise of satisfying the non -circularity of first antenna module, make the field shape of second antenna module also can obtain the promotion. Second antenna module can adopt dipole form, namely in left and right direction symmetry or relative symmetry setting. First parasitic branch as the parasitic branch of first main radiation branch, for increasing the circularity of antenna field shape. Can change the resonant frequency and parasitic current of parasitic branch through adjusting the length, position (swing radian) of first parasitic branch and the distance between main radiation branch etc. mode, and then make up the antenna field type defect of first antenna module and second antenna module, finally produce the radiation field type of non -circularity less (less than 5dB) respectively in horizontal plane, realize omnidirectional performance promotion.

Description

Technical Field

[0001] This utility model relates to the field of digital key product technology, and in particular to an integrated omnidirectional antenna and its digital key product. Background Technology

[0002] In traditional digital key products, the FOB (remote control) typically only has 433MHz or Bluetooth functionality. While BLE and UWB communication technologies are now widely used, digital keys integrating BLE and UWB technologies have not yet achieved comprehensive and in-depth development.

[0003] Existing technologies also include FOB solutions that integrate BLE and UWB technologies. These typically use ceramic antennas as radiating elements. Due to space constraints, they often have to adopt a conformal design between the antenna and the PCB. However, due to PCB obstruction and other reasons, the antenna pattern under this design is usually narrow and lacks roundness. The radiation pattern usually has large indentations and cannot achieve a uniform radiation pattern in all directions. This results in an unbalanced pull distance and unstable connection distances in all directions.

[0004] Therefore, it is necessary to design an antenna and digital key product with good omnidirectional performance. Utility Model Content

[0005] In order to overcome the technical problems of the existing technology, such as the difficulty in coexistence of dual or multiple antenna modules and the poor circularity of antenna field shape, this utility model provides an integrated omnidirectional antenna and its digital key product.

[0006] The technical solution adopted by this utility model to solve its problem is:

[0007] An integrated omnidirectional antenna, comprising:

[0008] Circuit board;

[0009] A first antenna module connected to the circuit board, the first antenna module including a first main radiating branch and a first parasitic branch, the first main radiating branch being disposed on one side of the circuit board in the horizontal direction;

[0010] The second antenna module connected to the circuit board includes a second main radiating stub, which is located on the other side of the circuit board in the horizontal direction, so that the feed point of the second main radiating stub is separated from the feed point of the first main radiating stub.

[0011] The first parasitic branch and the second main radiating branch are coupled with the first main radiating branch.

[0012] In the above technical solution, the first antenna module includes a first main radiating stub and a first parasitic stub, with the first main radiating stub generating the first antenna field shape. Specifically, the resonant frequency and parasitic current of the parasitic stub can be changed by adjusting its length, position (i.e., oscillation arc), and distance from the main radiating stub, thereby adjusting the horizontal field shape of the first antenna module. More specifically, the first antenna module utilizes the first parasitic stub to generate resonance slightly below 2.3 GHz, producing a new mode that compensates for the deficiencies in the antenna field shape generated by the first main radiating stub in a specific frequency band, ultimately generating a radiation field shape with lower non-circularity in the horizontal plane. The second antenna module includes a second main radiating stub, and the first and second antenna modules form a unified system. Provided the isolation is satisfied, the first parasitic stub, as part of the environment, improves the field shape of the second antenna module while also satisfying the non-circularity requirement of the first antenna module.

[0013] As a preferred embodiment, the second antenna module further includes a second parasitic stub, which is located on the opposite side of the second main radiating stub in the horizontal direction of the circuit board, allowing the feed point of the second main radiating stub to be separated from the ground point of the second parasitic stub.

[0014] In the above technical solution, the second antenna module includes a second main radiating stub and a second parasitic stub, which together form a dipole and have a symmetrical or relatively symmetrical structure in the horizontal direction of the circuit board. The first antenna module and the second antenna module become an integrated system. Under the premise of satisfying the isolation requirement, the first parasitic stub, as part of the environment, can also improve the field shape of the second antenna module while satisfying the non-circularity requirement of the first antenna module.

[0015] As a preferred embodiment, the second main radiating branch and the second parasitic branch form a dipole configuration, with the second main radiating branch located above the first parasitic branch and the second parasitic branch located above the first main radiating branch.

[0016] In the above technical solution, the first main radiating branch and the second parasitic branch are located on one side of the horizontal direction of the circuit board, and the first parasitic branch and the second main radiating branch are located on the other side of the center line of the circuit board, so as to generate an omnidirectional uniform coverage antenna field shape.

[0017] Furthermore, since the frequency band of the second antenna module (e.g., a UWB antenna) is higher than that of the first antenna module (e.g., a BLE antenna), the second antenna module is located at the top of the circuit board, while the first antenna module is located below the second antenna module.

[0018] As a preferred embodiment, the first parasitic branch is located on the opposite side of the first main radiating branch in the horizontal direction of the circuit board, so that the feed point of the first main radiating branch is separated from the ground point of the first parasitic branch, and the feed point of the first main radiating branch is separated from the ground point.

[0019] In the above technical solution, the first antenna module includes a first main radiating stub and a first parasitic stub. The first main radiating stub generates the first antenna field shape. The feed point of the first main radiating stub is separated from the ground point of the first parasitic stub, and the antenna operates through the mutual coupling between the first parasitic stub and the first main radiating stub. Specifically, by adjusting the length, position (i.e., swing radius) of the first parasitic stub and its distance from the main radiating stub, the resonant frequency and resonant mode of the first antenna module can be changed, thereby adjusting the horizontal field shape of the first antenna module.

[0020] As a preferred embodiment, the second main radiating branch, the second parasitic branch, and the first parasitic branch share the same ground plane of the circuit board.

[0021] Furthermore, the integrated omnidirectional antenna also includes a button, which shares the same ground plane on the circuit board as the second main radiating stub, the second parasitic stub, and the first parasitic stub. Through this design, the distance, position, and length between the two antenna modules can be optimized, ensuring the required isolation between them, thereby achieving dual-antenna coexistence.

[0022] As a preferred embodiment, the first main radiating stub includes a first arc segment, and the first parasitic stub includes a first arc segment. Both the first arc segment and the second arc segment are located within the clearance area of ​​the circuit board. That is, the swing arc of the first main radiating stub and the first parasitic stub must be limited within the clearance area of ​​the circuit board; otherwise, the radiation efficiency of the antenna will drop sharply.

[0023] Furthermore, when the first main radiating branch swings, its end should not be too close to the ground plane of the circuit board. Specifically, the distance between the end of the first main radiating branch and the ground plane of the circuit board should be greater than or equal to 3mm.

[0024] As a preferred embodiment, the length difference between the first parasitic branch and the first main radiating branch is 0-5 mm.

[0025] In the above technical solution, the length of the first parasitic branch is slightly greater than that of the first main radiating branch, or the length of the first main radiating branch is slightly greater than that of the first parasitic branch, thereby constructing a resonant mode with a similar resonant frequency and making up for the non-circularity of the field pattern of the first main radiating branch.

[0026] As a preferred embodiment, the first antenna module is a BLE (Bluetooth Low Energy) antenna; therefore, the first main radiating stub is a BLE main radiating stub, and the first parasitic stub is a BLE parasitic stub. The second antenna module is a UWB (Ultra-Wideband) antenna; therefore, the second main radiating stub is a UWB main radiating stub, and the second parasitic stub is a UWB parasitic stub.

[0027] As a preferred embodiment, the first main radiating stub is a PIFA antenna, and the feed point of the PIFA antenna is located above the ground point. Optimal impedance matching and antenna performance can be achieved by designing the distance between the feed point and the ground point.

[0028] As an alternative to the preferred option described above, the first main radiating stub is a monopole antenna, and the monopole antenna has only a feed point.

[0029] Based on the same design concept, this utility model also provides a digital key product, which includes the integrated omnidirectional antenna described above. This digital key product uses an onboard antenna solution, which not only ensures stable connection distances in all directions but also solves the compatibility issues between BLE and UWB antennas, and significantly reduces production costs.

[0030] In summary, the integrated omnidirectional antenna provided by this utility model has at least the following technical advantages compared to the prior art:

[0031] 1) The integrated omnidirectional antenna of this utility model integrates a first antenna module and a second antenna module. The first antenna module is used to generate the first antenna field shape, and the second antenna module is used to generate the second antenna field shape. The first antenna module and the second antenna module form a whole system. Under the premise of satisfying the isolation, the first parasitic branch, as part of the environment, can improve the field shape of the second antenna module while satisfying the non-circularity of the first antenna module.

[0032] 2) To match the layout of the first main radiating branch and the first parasitic branch, the second main radiating branch and the second parasitic branch of the second antenna module adopt a dipole form, that is, they are symmetrically or relatively symmetrically arranged in the left and right directions to ensure that the antenna field shape can be uniformly covered in all directions.

[0033] 3) The first parasitic stub of the first antenna module serves as a parasitic stub of the first main radiating stub. The feed points and ground points of the two are separated, and they work through mutual coupling. Specifically, the resonant frequency and parasitic current of the parasitic stub can be changed by adjusting the length, position (i.e., swing radius) of the first parasitic stub and its distance from the main radiating stub. This compensates for the antenna pattern defects generated by the first and second antenna modules, ultimately producing radiation patterns with smaller non-circularity (less than 5dB) in the horizontal plane, thus improving omnidirectional performance. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the integrated omnidirectional antenna of this utility model.

[0035] The meanings of the reference numerals in the attached figures are as follows:

[0036] 1. Circuit board; 2. First main radiating branch; 3. First parasitic branch; 4. Second main radiating branch; 5. Second parasitic branch. Detailed Implementation

[0037] To better understand and implement this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings.

[0038] In the description of this utility model, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0040] See Figure 1 As shown, according to the technical solution of this utility model, the integrated omnidirectional antenna includes a circuit board 1, a first antenna module and a second antenna module, both of which are connected to the circuit board 1.

[0041] The first antenna module includes a first main radiating stub 2 and a first parasitic stub 3. The first main radiating stub 2 is connected to a feed line and forms a feed point on the circuit board 1 for inputting radio frequency signals to the first main radiating stub 2, thereby transmitting electromagnetic waves to generate an antenna field shape. The first parasitic stub 3 is grounded and forms a ground point on the circuit board 1. The ground point of the first parasitic stub 3 is separately located from the feed point of the first main radiating stub 2. During operation, the first parasitic stub 3 is coupled to the first main radiating stub 2 to achieve its working principle. Specifically, the first antenna module uses the first main radiating stub 2 to generate a first antenna field shape, but this first antenna field shape has defects (e.g., pits). Therefore, the first parasitic stub 3 is used to generate a resonance slightly below 2.3 GHz, generating a new mode to compensate for the defects in the antenna field shape generated by the first main radiating stub 2 in a specific frequency band, ultimately producing a radiation field shape with low non-circularity (e.g., less than 5 dB) in the horizontal plane.

[0042] More specifically, this invention can also change the resonant frequency and parasitic current of the first parasitic branch 3 by adjusting the length, position (i.e., swing arc) and distance between the first parasitic branch 3 and the first main radiating branch 2, thereby compensating for the horizontal field shape defects generated by the first antenna module.

[0043] In addition, the second antenna module includes a second main radiating stub 4, which makes the first antenna module and the second antenna module a whole system. Under the premise of satisfying the isolation, the first parasitic stub, as part of the environment, can also improve the field shape of the second antenna module while satisfying the non-circularity of the first antenna module.

[0044] In a preferred embodiment, the second antenna module includes a second main radiating stub 4 and a second parasitic stub 5. The second parasitic stub 5 is grounded, forming a grounding point on the circuit board 1. The second parasitic stub 5 is located on the opposite side of the second main radiating stub 4 in the horizontal direction of the circuit board 1, so that the feed point of the second main radiating stub 4 is separated from the grounding point of the second parasitic stub 5.

[0045] During operation, the second antenna field shape generated by the second main radiating stub 4 and the second parasitic stub 5 coexists with the antenna field shape generated by the first antenna module without affecting each other, thus solving the problem of coexistence of the two antenna modules. More specifically, the second antenna field shape generated by the second main radiating stub 4 and the second parasitic stub 5 is also adjusted by the first parasitic stub 3. In the case of defects in the second antenna field shape (such as pits), the resonance generated by the first parasitic stub 3 can be used to compensate for the defects in the antenna field shape generated by the second main radiating stub 4 and the second parasitic stub 5, ultimately producing a second antenna field shape with a small non-circularity (e.g., less than 5dB) in the horizontal plane.

[0046] Furthermore, the second main radiating stub 4 and the second parasitic stub 5 form a dipole configuration. The dipole configuration of the second main radiating stub 4 and the second parasitic stub 5 includes a structure in which they are symmetrically or relatively symmetrically arranged in the horizontal direction of the circuit board 1. Specifically, the dipole configuration of the second main radiating stub 4 and the second parasitic stub 5 matches the layout of the first main radiating stub 2 and the first parasitic stub 3, ensuring that both antenna field shapes can provide omnidirectional and uniform coverage.

[0047] In a preferred embodiment, the first antenna module employs a BLE (Bluetooth Low Energy) antenna; therefore, the first main radiating stub 2 is a BLE main radiating stub, and the first parasitic stub 3 is a BLE parasitic stub. The second antenna module employs a UWB (Ultra-Wideband) antenna; therefore, the second main radiating stub 4 and the second parasitic stub 5 are both UWB parasitic stubs. Through the above design, the integrated omnidirectional antenna of this invention integrates BLE and UWB technologies, realizing multi-band functionality.

[0048] In one alternative, the first main radiating stub 2 employs a PIFA antenna, which includes a feed point and a ground point, which are separately configured. The feed point is the connection point between the PIFA antenna and the feed line, used to provide energy for the antenna's radiation and to serve as a signal transmission point. By designing the distance between the feed point and the ground point, optimal impedance matching and antenna performance can be achieved.

[0049] In another alternative, the first main radiating stub 2 is a single-stage sub-antenna, which includes only the feed point.

[0050] In one embodiment of this utility model, the second main radiating branch 4, the second parasitic branch 5, and the first parasitic branch 3 share the same ground plane of the circuit board 1. Structurally, the second main radiating branch 4 and the second parasitic branch 5 can share the same grounding part, which is connected to the ground plane of the circuit board 1, thus achieving a common ground. The first parasitic branch 3 can have its own grounding part designed at its end, which is then connected to the ground plane of the circuit board 1, thus achieving a common ground with the second main radiating branch 4 and the second parasitic branch 5.

[0051] Furthermore, the integrated omnidirectional antenna also includes a button, which shares the same ground plane of circuit board 1 with the second main radiating stub 4, the second parasitic stub 5, and the first parasitic stub 3. Through this design, the distance, position, and length between the first antenna module and the second antenna module can be optimized, ensuring that the isolation between the two antenna modules meets the requirements, thereby achieving dual-antenna coexistence.

[0052] More specifically, in terms of structural design, the button is positioned above the horizontal plane of the circuit board 1, and the contact point below the button makes good contact with one side of the ground plane of the circuit board 1. The grounding parts of the second main radiating branch 4, the second parasitic branch 5, and the first parasitic branch 3 make good contact with the other side of the ground plane of the circuit board 1, thereby achieving common grounding.

[0053] In a preferred embodiment, the first main radiating stub 2 and the second parasitic stub 5 are located on one side of the horizontal direction of the circuit board 1, and the first parasitic stub 3 and the second main radiating stub 4 are located on the other side of the horizontal direction of the circuit board 1. This makes the first main radiating stub 2 and the first parasitic stub 3 symmetrical or relatively symmetrical with respect to the center line of the circuit board 1, generating a uniform first antenna field shape; and the second main radiating stub 4 and the second parasitic stub 5 symmetrical or relatively symmetrical with respect to the center line of the circuit board 1, generating a uniform second antenna field shape, ultimately achieving two omnidirectional uniform coverage antenna field shape distributions.

[0054] Furthermore, when the second antenna module uses a high-frequency antenna (such as a UWB antenna, typically operating in the 3.1GHz to 10.6GHz band), it requires a larger space for signal radiation to achieve wideband coverage. Therefore, it is positioned at the top of circuit board 1, close to the top edge. The first antenna module, using a low-frequency antenna (such as a BLE antenna, typically operating in the 2.4GHz band), can be positioned below the second antenna module to avoid interference between the two antenna patterns.

[0055] In one embodiment of this utility model, the first main radiating stub 2 includes a first arc-shaped segment, and the first parasitic stub 3 includes a second arc-shaped segment. The first and second arc-shaped segments are the swingable parts of the first main radiating stub 2 and the first parasitic stub 3, respectively, used to adjust their respective positions. Specifically, the first and second arc-shaped segments are both located within the clearance area of ​​the circuit board 1, that is, the swing radius of the first main radiating stub 2 and the first parasitic stub 3 must be limited within the clearance area of ​​the circuit board 1 to avoid a sharp decrease in the radiation efficiency of the first antenna module.

[0056] Furthermore, when the first arc segment of the first main radiating branch 2 is adjusted in terms of its swing radius, the end of the first main radiating branch 2 (i.e., the end furthest from the feed point) should not be too close to the ground plane of the circuit board 1. Specifically, the distance between the end of the first main radiating branch 2 and the ground plane of the circuit board 1 should be greater than or equal to 4 mm.

[0057] In a preferred embodiment, the length difference between the first parasitic branch 3 and the first main radiating branch 2 is 0-5 mm. Specifically, the length of the first parasitic branch 3 is slightly greater than the length of the first main radiating branch 2 (within 5 mm), or the length of the first parasitic branch 3 is slightly less than the length of the first main radiating branch 2 (within 5 mm), thereby constructing a resonant mode with a similar resonant frequency and compensating for the non-circularity of the field pattern of the first main radiating branch 2.

[0058] Based on the same design concept, this utility model also provides an embodiment of a digital key product, which includes an integrated omnidirectional antenna of the above scheme.

[0059] The digital key product adopts an onboard antenna solution, integrating at least two antenna modules. This not only ensures stable connection distances in all directions but also solves the compatibility issues between BLE and UWB antennas, and significantly reduces production costs.

[0060] The technical means disclosed in this utility model are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this utility model, and these improvements and modifications are also considered within the scope of protection of this utility model.

Claims

1. An integrated omnidirectional antenna, characterized in that, include: Circuit board; A first antenna module connected to the circuit board, the first antenna module including a first main radiating branch and a first parasitic branch, the first main radiating branch being disposed on one side of the circuit board in the horizontal direction; The second antenna module connected to the circuit board includes a second main radiating stub, which is located on the other side of the circuit board in the horizontal direction, so that the feed point of the second main radiating stub is separated from the feed point of the first main radiating stub. The first parasitic branch and the second main radiating branch are coupled with the first main radiating branch.

2. The integrated omnidirectional antenna according to claim 1, characterized in that, The second antenna module further includes a second parasitic stub, which is located on the opposite side of the second main radiating stub in the horizontal direction of the circuit board.

3. The integrated omnidirectional antenna according to claim 2, characterized in that, The second main radiating branch and the second parasitic branch form a dipole, with the second main radiating branch located above the first parasitic branch.

4. The integrated omnidirectional antenna according to claim 1, characterized in that, The first parasitic branch is located on the opposite side of the first main radiating branch in the horizontal direction of the circuit board, so that the feed point of the first main radiating branch is separated from the ground point of the first parasitic branch, and the feed point of the first main radiating branch is separated from the ground point.

5. The integrated omnidirectional antenna according to claim 2, characterized in that, The integrated omnidirectional antenna also includes a button, and the button, the second main radiating stub, the second parasitic stub, and the first parasitic stub share the same ground plane of the circuit board.

6. The integrated omnidirectional antenna according to claim 1, characterized in that, The first main radiating branch includes a first arc-shaped segment, and the first parasitic branch includes a second arc-shaped segment. Both the first arc-shaped segment and the second arc-shaped segment are located within the clearance area where the circuit board is located.

7. The integrated omnidirectional antenna according to claim 1, characterized in that, The distance between the end of the first main radiating branch and the ground plane of the circuit board is greater than or equal to 3 mm.

8. The integrated omnidirectional antenna according to claim 1, characterized in that, The length difference between the first parasitic branch and the first main radiating branch is 0-5 mm.

9. The integrated omnidirectional antenna according to any one of claims 1-8, characterized in that, The first antenna module is a BLE antenna, and the second antenna module is a UWB antenna.

10. A digital key product, characterized in that, Including the integrated omnidirectional antenna as described in any one of claims 1-9.

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