Antenna structure and communication device

Abstract

This invention relates to the field of antenna technology and discloses an antenna structure and communication device. The antenna structure includes a metal outer wall and an antenna element. The metal outer wall includes a top plate, a bottom plate, and side plates, which together form a box with a cavity. A first opening communicating with the cavity is provided on the top plate, and a second opening communicating with the cavity is provided on one of the side plates. The first and second openings are interconnected on the box. The antenna element is disposed at the first opening and does not protrude from the upper surface of the top plate. The antenna element's placement at the first opening allows for the generation of an ultra-wideband (UWB) frequency band within a preset frequency range. Simultaneously, the cavity allows for the excitation of two different frequency dual-Wi-Fi bands, achieving the effect of a single antenna covering multiple different frequency bands and reducing the installation cost of the communication device.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and in particular to an antenna structure communication device. Background Technology

[0002] With the development of communication equipment, people are paying attention not only to the communication performance of these devices but also to their appearance and design. Communication devices with metal casings are becoming increasingly popular. However, electromagnetic waves cannot penetrate metal. Completely enclosing the antenna within a metal casing would not meet the antenna performance testing standards. Therefore, an opening is usually placed at the antenna location to ensure that electromagnetic waves can be radiated.

[0003] The inventors discovered that current antenna configurations have at least the following problems: the frequency bands covered by a single antenna cannot meet the diverse wireless communication needs, thus requiring multiple antennas to be added to the device to cover different frequency bands. However, portable devices require a smaller size, which makes it impossible to install multiple antennas in the limited space of a portable device, thus hindering the achievement of coverage for multiple different frequency bands. Summary of the Invention

[0004] The purpose of this invention is to provide an antenna structure and a communication device. The antenna structure of this invention is particularly suitable for communication devices with all-metal back covers, and it achieves the application effect of a single antenna covering multiple different frequency bands, thereby reducing the installation cost of the communication device.

[0005] To solve the above-mentioned technical problems, embodiments of the present invention provide an antenna structure, including: a metal outer wall and an antenna element. The metal outer wall includes a top plate, a bottom plate, and a side plate, and the top plate, bottom plate, and side plate form a box with a cavity. A first opening communicating with the cavity is opened on the top plate, and a second opening communicating with the cavity is opened on one of the side plates, and the first opening and the second opening are interconnected on the box. The antenna element is disposed at the position of the first opening, and the antenna element does not protrude from the upper surface of the top plate.

[0006] Embodiments of the present invention also provide a communication device, such as the antenna structure and all-metal back cover described above, wherein the base plate of the antenna structure is close to the metal back cover.

[0007] Compared to existing technologies, this invention's embodiments feature a metal outer wall with a top plate, bottom plate, and side plates forming a cavity-like housing. A first opening communicating with the cavity is located on the top plate, and a second opening communicating with the cavity is located on one of the side plates. The first and second openings are interconnected within the housing. An antenna element is positioned at the first opening, generating an ultra-wideband (UWB) frequency band within the 8-20 GHz range. Simultaneously, the cavity-like housing can excite dual Wi-Fi frequency bands of 2.4-2.5 GHz and 5.1-5.8 GHz, achieving the effect of a single antenna covering multiple different frequency bands and reducing the installation cost of communication equipment.

[0008] In addition, the first opening includes: a rectangular branch opening, and an I-shaped branch opening formed by extending outward along one side of the rectangular branch opening, wherein the orientation of the I-shaped branch opening is the same as the orientation of one side of the top plate; the antenna element is disposed at the rectangular branch opening.

[0009] In addition, the size of the rectangular branch opening is larger than the size of the antenna element.

[0010] In addition, the placement of the antenna element changes depending on the placement of the rectangular branch opening, and the impedance of the antenna element also changes depending on its placement.

[0011] In addition, the antenna structure also includes a support member; the support member is used to support the antenna element at the first opening position.

[0012] Additionally, the support includes a grounding post; the grounding post is also used to connect the antenna element to the metal outer wall.

[0013] In addition, the antenna element is circular in shape.

[0014] In addition, the antenna structure covers 8GHz to 20GHz, 2.4GHz to 2.5GHz and 5.1GHz to 5.8GHz.

[0015] In addition, the antenna element is a microstrip antenna, and the impedance of the microstrip antenna is in the range of 50Ω to 100Ω. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments, and the figures in the drawings are not to be limited by scale.

[0017] Figure 1 This is a schematic diagram of the antenna structure according to an embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of the antenna element according to an embodiment of the present invention;

[0019] Figure 3 This is a schematic diagram illustrating the simulation effect of the reflection coefficient of the antenna structure according to an embodiment of the present invention;

[0020] Figure 4 This is a schematic diagram illustrating the simulation effect of the voltage standing wave ratio of the antenna structure according to an embodiment of the present invention;

[0021] Figure 5 This is a schematic diagram illustrating the simulation effect of the antenna structure gain according to an embodiment of the present invention;

[0022] Figure 6 This is the radiation pattern of the antenna structure in the E-plane of the 2.4GHz frequency band according to an embodiment of the present invention;

[0023] Figure 7 This is the radiation pattern of the antenna structure in the H-plane at a frequency of 2.4 GHz according to an embodiment of the present invention;

[0024] Figure 8 This is the radiation pattern of the antenna structure in the E-plane at a frequency of 5.1 GHz according to an embodiment of the present invention;

[0025] Figure 9 This is the radiation pattern of the antenna structure in the H-plane of the 5.1 GHz band according to an embodiment of the present invention;

[0026] Figure 10 This is the radiation pattern of the antenna structure in the E-plane at a frequency of 10 GHz according to an embodiment of the present invention;

[0027] Figure 11 This is the radiation pattern of the antenna structure in the H-plane of the 10GHz band according to an embodiment of the present invention;

[0028] Figure 12 This is the radiation pattern of the antenna structure in the E-plane at 15 GHz according to an embodiment of the present invention;

[0029] Figure 13 This is the radiation pattern of the antenna structure in the H-plane at the 15GHz frequency band according to an embodiment of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of the present invention to enable the reader to better understand this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0031] The division of the following embodiments is for ease of description and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined with and referenced by each other without contradiction.

[0032] Embodiments of the present invention relate to an antenna structure, such as... Figure 1 As shown, it includes: a metal outer wall 1 and an antenna element 2. The metal outer wall 1 includes a top plate, a bottom plate and a side plate, and the top plate, bottom plate and side plate form a box with a cavity. A first opening 3 communicating with the cavity is opened on the top plate, and a second opening 4 communicating with the cavity is opened on one of the side plates, and the first opening 3 and the second opening 4 are interconnected on the box. The antenna element 2 is disposed at the position of the first opening 3, and the antenna element 2 does not protrude from the upper surface of the top plate.

[0033] Compared to existing technologies, this invention's embodiments feature a metal outer wall comprising a top plate, bottom plate, and side plates that together form a cavity-like housing. A first opening communicating with the cavity is located on the top plate, and a second opening communicating with the cavity is located on one of the side plates. The first and second openings are interconnected within the housing. An antenna element is positioned at the first opening, generating an ultra-wideband (UWB) frequency band within the 8-20 GHz range. Simultaneously, the cavity-like housing can excite dual Wi-Fi frequency bands at 2.4 GHz and 5.1 GHz, achieving the effect of a single antenna covering multiple different frequency bands. This reduces the number of antennas required in communication devices, thereby lowering installation costs and allowing for easier installation of the antenna structure into small, portable devices.

[0034] In this embodiment, the first opening 3 includes a rectangular branch opening 31 and an I-shaped branch opening 32 extending outward from one side of the rectangular branch opening 31, wherein the orientation of the I-shaped branch opening 32 is the same as that of one side of the top plate; the antenna element 2 is disposed at the rectangular branch opening 31. Alternatively, the second opening can also be I-shaped or a slit to achieve better excitation effect. The first and second openings are formed by cutting, and their positions and sizes are adjusted according to the required frequency band. The positions of the first opening on the top plate and the second opening on the side plate, as well as the sizes of the two openings, are not limited here.

[0035] In addition, the size of the rectangular branch opening 31 is slightly larger than the size of the antenna element, that is, there is a gap between the edge of the antenna element and the edge of the rectangular branch opening, so as to facilitate the installation of the antenna element.

[0036] In addition, the position of the antenna element 2 changes with the position of the rectangular branch opening 31, and the impedance of the antenna element 2 changes with the position of the antenna element 2.

[0037] In addition, the structure of antenna element 2 is as follows: Figure 2 As shown, the antenna body 21, dielectric substrate 22, and ground plane 23 are arranged in different layers, with the dielectric substrate being closer to the antenna body layer than the ground plane. Figure 2 The feed line width 24 of the antenna element can be calculated in the following way:

[0038]

[0039] Among them, w f Represents the feed line width, ε r Representing the dielectric constant, B is calculated using the following formula: Where Z0 represents the characteristic impedance.

[0040] The characteristic impedance of each segment of the tapered microstrip line of an antenna element ranges from 100Ω to 50Ω, and can be calculated using the following formula:

[0041]

[0042] Among them, L f Z represents the length of the tapered microstrip line. L This represents the load impedance.

[0043] In addition, the antenna structure also includes a support member; the support member is used to support the antenna element at the first opening position. The support member supports the antenna element, ensuring that the antenna element can be close to the top plate of the housing. Figure 1 As shown, the support includes a grounding post 5; the grounding post 5 is also used to connect the antenna element to the metal outer wall. Specifically, the grounding post 5 connects the ground plane 23 of the antenna element to the metal outer wall so that the antenna element can function properly. The antenna element type can be a UWB antenna.

[0044] Furthermore, the antenna element is a monopole antenna with a circular shape. The antenna structure covers frequency bands from 8 GHz to 20 GHz, 2.4 GHz, and 5.1 GHz. While the type and shape of the antenna element can be replaced with other types of patch antennas as needed, a monopole antenna is the optimal choice considering the smallest possible antenna for best performance.

[0045] In addition, the antenna structure in this invention can be improved based on the standard dimensions of cavity back antennas, so that the dimensions of the resulting antenna structure can be adapted to most current electronic devices, facilitating the installation of the antenna structure.

[0046] To facilitate the explanation of the simulation effect of the antenna structure in the embodiments of the present invention, the following details the reflection coefficient, voltage standing wave ratio, gain, and radiation pattern:

[0047] The simulation results of the antenna structure's reflection coefficient are as follows: Figure 3 As shown, the antenna structure exhibits good radiation performance in the WiFi-1 2.4GHz band, the WiFi-2 4.4-6.1GHz band, and the UWB 8.6-20GHz band. Furthermore, compared to existing conventional antennas, the antenna structure of this invention achieves an improvement of 2-3 dBm.

[0048] The voltage standing wave ratio simulation effect of the antenna structure is as follows: Figure 4 As shown, when the VSWR is equal to 1, it indicates that the impedance of the feed line and the antenna are perfectly matched. At this time, all high-frequency energy is radiated by the antenna, and there is no energy reflection loss, i.e. Figure 4 As shown, the voltage standing wave ratio (VSWR) is 1.7 in the WiFi-1 2.4GHz band, 1.9 in the WiFi-2 5.1GHz band, 1.3 in the UWB 10GHz band, and 1.3 in the UWB 15GHz band, all of which achieve excellent antenna performance. At the same time, all frequency bands with a VSWR close to 1 in the figure also have excellent antenna performance.

[0049] The gain simulation effect of the antenna structure is as follows Figure 5 As shown, the gain is 3.5dBi in the WiFi-1 2.4GHz band, 5.3dBi in the WiFi-2 5.1GHz band, 5.5dBi in the UWB 10GHz band, and 8dBi in the UWB 15GHz band.

[0050] In addition, the radiation patterns of the antenna structure in the E-plane and H-plane at 2.4 GHz are as follows: Figures 6 to 7 As shown, the radiation patterns of the E-plane and H-plane in the 5.1 GHz band are as follows: Figures 8 to 9 As shown, the radiation patterns of the E-plane and H-plane in the 10GHz band are as follows: Figures 10 to 11 As shown, the radiation patterns of the E-plane and H-plane in the 15GHz band are as follows: Figures 12 to 13 As shown, in each directional pattern, solid lines represent co-polarization directions, and dashed lines represent cross-polarization directions.

[0051] This invention also relates to a communication device, such as the antenna structure and all-metal back cover described above, wherein the base plate of the antenna structure is close to the metal back cover. The communication device can be a laptop, tablet, mobile hotspot (MiFi), data card, Bluetooth (BT) headset, router, Internet of Things (IoT), etc.

[0052] The antenna structure in this embodiment is consistent with the implementation details in the previous antenna structure embodiment. The relevant technical details mentioned in the antenna structure embodiment are still valid in this embodiment. In order to reduce repetition, they will not be repeated here.

[0053] Those skilled in the art will understand that the above embodiments are specific embodiments for implementing the present invention, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the present invention.

Claims

1. An antenna structure, characterized by The antenna structure comprises: a metal outer wall and an antenna element, the metal outer wall comprising a top plate, a bottom plate and side plates, and the top plate, the bottom plate and the side plates enclosing a box body with a cavity; a first opening is formed on the top plate and communicates with the cavity, one of the side plates is provided with a second opening which communicates with the cavity, and the first opening and the second opening are in communication with each other on the box body; the antenna element is arranged at the position of the first opening, and the antenna element does not protrude from the upper surface of the top plate; the first opening comprises a rectangular branch opening and an I-shaped branch opening which is formed by extending outward along one side of the rectangular branch opening, and the I-shaped branch opening has the same direction as one side of the top plate; the antenna element is arranged at the rectangular branch opening; the size of the rectangular branch opening is larger than that of the antenna element, and there is a gap between the edge of the antenna element and the edge of the rectangular branch opening.

2. The antenna structure of claim 1, wherein, The arrangement position of the antenna element changes with the arrangement position of the rectangular branch opening, and the impedance of the antenna element changes with the different arrangement positions of the antenna element.

3. The antenna structure of claim 1, wherein, The antenna structure comprises: a support; the support is used to support the antenna element at the position of the first opening.

4. The antenna structure of claim 3, wherein, The support comprises a grounding column; the grounding column is also used to connect the antenna element to the metal outer wall.

5. The antenna structure of claim 1, wherein, The shape of the antenna element is circular.

6. The antenna structure of claim 1, wherein, The antenna structure covers 8GHz to 20GHz, 2.4GHz to 2.5GHz and 5.1GHz to 5.8GHz.

7. The antenna structure of claim 1, wherein, The antenna element is a microstrip antenna, and the impedance of the microstrip antenna is in the range of 50Ω to 100Ω.

8. A communication device, characterized by The antenna structure and the metal back cover as claimed in any one of claims 1 to 7 are provided, wherein the bottom plate of the antenna structure is close to the metal back cover.

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