Resonant cavity antenna for mobile equipment and mobile equipment

Abstract

The invention provides a resonant cavity antenna for mobile equipment and the mobile equipment. The resonant cavity antenna for the mobile equipment comprises a metal shell, a feed end and a grounding part, the metal shell is used for forming a resonant cavity with a mainboard of the mobile equipment and is electrically connected with the ground end of the mainboard of the mobile equipment; the feed end is connected with the metal shell; the grounding part is used for being connected with a screen protection metal plate of the mobile equipment, the grounding part is arranged on the face, away from the metal bottom plate, of the metal shell, and the distance between the grounding part and the edge, close to the feed end, of the metal shell is 1 / 4-1 / 2 of the resonant wavelength; the metal shell is at least one of a copper shell, a steel shell and an aluminum shell. The resonant cavity antenna for the mobile equipment is clear in resonant area, is suitable for the mobile equipment with an all-metal machine body, is small in occupied space, can realize certain antenna clearance, and is beneficial to improving the efficiency of the antenna.

Description

Technical Field

[0001] The invention belongs to the technical field of antennas, and in particular relates to a resonant cavity antenna for a mobile device and the mobile device. Background Art

[0002] Combo antennas for smartphones and tablets, also known as WiFi & BT antennas, are smaller in size and not as important as the main antenna, but their performance can directly affect the customer's experience. In tablets, WiFi is the main network connection mode, and its performance can be directly reflected in the user's use process. In addition, WiFi antennas usually need to support 5G WiFi, and the increase in frequency bands has brought challenges to antenna design, making it difficult to balance performance. The efficiency of the combo antenna directly affects the actual use effect of customers.

[0003] The Combo antennas in current mobile phones are usually installed inside the entire casing, and the entire casing is usually made of plastic or a metal frame design. As the overall thickness of mobile phones continues to decrease, the design space for Combo antennas has been squeezed. Most of the existing antenna designs are located on the antenna bracket inside the mobile phone or on the inside of the middle frame / back shell, using FPC (flexible printed circuit) or LDS / PDS (laser direct structuring / plastic laser direct structuring) laser engraving technology for routing as part of the antenna, or directly using the metal frame as the antenna. At present, the commonly used routing form of Combo antennas is double-elastic foot IFA / loop. However, the current environment is relatively complex, and the bandwidth of existing antenna forms is narrow, making it difficult to meet the needs of 2.4G and 5G WiFi at the same time, resulting in poor WiFi performance.

[0004] In addition, currently popular mobile phones and tablets generally adopt full-screen and all-metal body designs, which reduces the clearance area of ​​the antenna and increases the difficulty of antenna design. The existing antenna solutions are no longer suitable for these new design requirements. This brings new challenges to antenna design. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings and deficiencies in the prior art and to provide a resonant cavity antenna for a mobile device, which has a clear resonance area and is suitable for mobile devices with an all-metal body. The antenna occupies a small space and can achieve a certain antenna clearance, which is beneficial to improving the antenna efficiency.

[0006] The present invention provides a resonant cavity antenna for a mobile device, comprising a metal shell, a feeding end and a grounding portion; the metal shell is used to form a resonant cavity with a mainboard of the mobile device and is electrically connected to a grounding end of the mainboard of the mobile device; the feeding end is connected to the metal shell; the grounding portion is used to connect to a screen protection metal plate of the mobile device, the grounding portion is arranged on a side of the metal shell away from the metal bottom plate, and the distance between the grounding portion and the edge of the metal shell close to the feeding end is 1 / 4-1 / 2 of the resonant wavelength; the metal shell is at least one of a copper shell, a steel shell and an aluminum shell.

[0007] In the resonant cavity antenna for mobile devices provided by the present invention, the metal shell is used to form a resonant cavity with the mainboard, and the grounding part is arranged on the side of the metal shell away from the metal bottom plate, so that the grounding part is short-circuited with the screen protection metal plate of the mobile device, and the distance between the grounding part and the edge of the metal shell close to the feeding end is used to adjust the resonant wavelength to achieve control of the antenna frequency band and bandwidth; the vertical projection of the metal shell on the mainboard forms the antenna clearance, and the resonant cavity excitation is achieved through the feeding end. The resonant cavity antenna for mobile devices of the present invention has a clear resonance area and is suitable for mobile devices with an all-metal body. The antenna occupies a small space and can achieve a certain antenna clearance, which is conducive to improving the antenna efficiency.

[0008] Furthermore, the metal shell includes a radiating metal surface and a side end surface protruding from the edge of the radiating metal surface, the radiating metal surface is used to form a resonant cavity with the mainboard of the mobile device, and the side end surface is used to be electrically connected to the ground terminal of the mainboard of the mobile device; the grounding portion is located outside the resonant cavity and is arranged on one side of the radiating metal surface, and the side end surface is protruded from a side of the radiating metal surface away from the grounding portion; the feeding end is arranged at the edge of the radiating metal surface.

[0009] Furthermore, the grounding part is a grounding foam. The grounding foam has good flexibility, can adapt to electronic components and circuit boards of different shapes, and can achieve close contact with the screen protection metal plate of the mobile device to maintain effective connection.

[0010] Furthermore, the grounding foam is in a strip shape and is arranged parallel to the length direction or width direction of the radiating metal surface. The strip-shaped grounding foam can form a regular antenna clearance, and the antenna resonance area is clear, which is conducive to conveniently adjusting the resonance frequency.

[0011] Furthermore, the feed end protrudes from the edge of the radiating metal surface and is arranged away from the grounding portion, and the protruding height of the feed end is the same as the height of the side end surface. In addition to exciting the resonant cavity, the feed end can also play a certain supporting role for the radiating metal surface.

[0012] Furthermore, at least one support portion is provided on a protrusion of the radiating metal surface away from the grounding portion, and the support portion has the same height as the protrusion of the feeding end. The support portion plays a certain supporting role on the radiating metal surface to ensure the height of the resonant cavity and prevent the radiating metal surface from collapsing under external force impact.

[0013] Furthermore, the operating frequency band of the resonant cavity is the 2.4G WiFi band or the 5G WiFi band, and the distance between the ground portion and the edge of the metal shell close to the feeding end is 1 / 4-1 / 2 of the resonant wavelength of the 5G WiFi band. The distance between the ground portion and the edge of the metal shell close to the feeding end is used to control the radiation frequency band. To ensure antenna efficiency, the distance is 1 / 4-1 / 2 of the resonant wavelength of the 5G WiFi band.

[0014] Furthermore, the height of the resonant cavity is ≥1 mm. The height of the resonant cavity is limited to ensure that the antenna reaches resonance at the designed operating frequency, and maintains high gain and bandwidth while reducing the size of the antenna.

[0015] The present invention also provides a mobile device, comprising a screen protection metal plate, a main board, a metal base plate and the above-mentioned resonant cavity antenna for the mobile device; the screen protection metal plate and the metal base plate are interconnected and enclosed to form a containing space; the main board is located in the containing space and is arranged on the metal base plate; the metal shell of the resonant cavity antenna for the mobile device is located in the containing space and is arranged on the metal base plate, and a resonant cavity is formed between the metal shell and the main board; the feeding end is electrically connected to the main board; the grounding part is connected to the screen protection metal plate of the mobile device.

[0016] In the mobile device provided by the present invention, the screen protection metal plate and the metal bottom plate are enclosed to form an accommodation space, the mainboard and the metal shell are used to form a resonant cavity, and the grounding part is located on the metal shell and is arranged away from the resonant cavity to short-circuit with the screen protection metal plate to form an antenna loop. The resonance area of ​​the mobile device provided by the present invention is clear, and the resonant frequency and bandwidth can be adjusted by adjusting the position of the grounding part. The optimization is convenient and fast, and it is suitable for mobile devices with all-metal bodies. The vertical projection of the metal shell on the mainboard forms an antenna clearance, thereby improving the antenna performance.

[0017] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the resonant cavity antenna for mobile device of Example 1.

[0019] Figure 2 Schematic diagram of the resonant cavity of the resonant cavity antenna for mobile device of Example 1.

[0020] Figure 3 It is a schematic diagram of the connection between the resonant cavity antenna for mobile device and the mainboard of Example 1.

[0021] Figure 4 This is a diagram of the S11 parameters of the resonant cavity antenna for mobile devices according to the first embodiment.

[0022] Figure 5 This is a diagram showing the antenna efficiency of the resonant cavity antenna for mobile device according to Example 1.

[0023] Figure 6 This is a schematic diagram of the internal connections of a mobile device of Example 2. DETAILED DESCRIPTION

[0024] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the embodiments of the present invention, rather than to limit the embodiments of the present invention. It is also necessary to explain that, for ease of description, only parts related to the embodiments of the present invention are shown in the accompanying drawings, rather than all structures.

[0025] In addition, the terms first, second, third, etc. in the specification and claims are only used for the purpose of describing the same technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated, nor necessarily describing the order or time sequence. The terms are interchangeable where appropriate. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0026] Similarly, the terms "fixed" and "connected" used in the specification and claims should not be construed as limited to direct connection. Therefore, the expression "device A is connected to device B" should not be limited to a device or system in which device A is directly connected to device B, but means that there is a path between device A and device B, which may be a path including other devices or tools.

[0027] Example 1

[0028] This embodiment provides a resonant cavity antenna for a mobile device. Figure 1 This is a schematic diagram of the structure of a resonant cavity antenna for mobile devices. Figure 2 is a schematic diagram of a resonant cavity of a resonant cavity antenna for a mobile device. Figure 3 This is a schematic diagram of the connection between the resonant cavity antenna and the motherboard for mobile devices. Figure 1-3The resonant cavity antenna for a mobile device comprises a metal shell 1, a feeding terminal 2 and a grounding portion 3; the metal shell 1 is used to form a resonant cavity with a mainboard 6 of the mobile device and is electrically connected to the ground terminal of the mainboard 6 of the mobile device; the feeding terminal 2 is connected to the metal shell 1; the grounding portion 3 is used to connect to a screen protection metal plate 5 of the mobile device, and the grounding portion 3 is arranged on a side of the metal shell 1 away from the metal bottom plate 7, and the distance between the grounding portion 3 and the edge of the metal shell 1 close to the feeding terminal 2 is 1 / 4-1 / 2 of the resonant wavelength; the metal shell is at least one of a copper shell, a steel shell, and an aluminum shell.

[0029] In the resonant cavity antenna for mobile devices provided in this embodiment, the metal shell 1 is used to form a resonant cavity with the mainboard 6, and the grounding portion 3 is arranged on the side of the metal shell 1 away from the metal bottom plate 7, so that the grounding portion 3 is short-circuited with the screen protection metal plate 5 of the mobile device, and the distance between the grounding portion 3 and the edge of the metal shell 1 close to the feeding terminal 2 is used to adjust the resonant wavelength to achieve control of the antenna frequency band and bandwidth; the vertical projection of the metal shell 1 on the mainboard 6 forms the antenna clearance, and the resonant cavity excitation is achieved through the feeding terminal 2. The resonant cavity antenna for mobile devices of the present invention has a clear resonant area and is suitable for mobile devices with all-metal bodies. The antenna occupies a small space and can achieve a certain antenna clearance, which is conducive to improving the antenna efficiency. Compared with the prior art, the resonant cavity antenna for mobile devices of this embodiment does not need to open a seam on the device and subsequent nano injection molding operations, which avoids affecting the beauty of the whole machine and reduces the cost. It can directly use at least one of the copper shell, steel shell, and aluminum shell and the structure of the device itself to form a resonant cavity antenna to provide an excellent transmission signal.

[0030] See also Figure 1-3 In this embodiment, the metal shell 1 includes a radiating metal surface 11 and a side end surface 12 protruding from the edge of the radiating metal surface 11, the radiating metal surface 11 is used to form a resonant cavity with the mainboard 6 of the mobile device, and the side end surface 12 is used to be electrically connected to the ground end of the mainboard 6 of the mobile device; the grounding portion 3 is located outside the resonant cavity and is arranged on one side of the radiating metal surface 11, and the side end surface 12 is protruded from a side of the radiating metal surface 11 away from the grounding portion 3; the feeding terminal 2 is arranged at the edge of the radiating metal surface 11.

[0031] The side surface 12 is grounded separately from the grounding portion 3 to achieve impedance matching and reduce interference. The side surface 12 is in a strip shape, which is firmly connected to the ground end of the mainboard 6 of the mobile device and can also play a certain supporting role for the radiating metal surface 11 to form a resonant cavity of a certain height.

[0032] In one embodiment, the metal shell 1 is one of a copper shell, a steel shell, and an aluminum shell.

[0033] See also Figure 1-3In this embodiment, the grounding portion 3 is a grounding foam 31. The grounding foam 31 has good flexibility, can adapt to electronic components and circuit boards of different shapes, and can achieve close contact with the screen protection metal plate 5 of the mobile device to maintain effective connection. The feeding end 2, the grounding portion 3, the radiating metal surface 11 between the feeding end 2 and the grounding portion 3, and the metal bottom plate 7 of the mobile device form a resonant cavity for antenna radiation, and the position of the grounding portion 2 can be changed to change the width of the radiating metal surface 11 between the feeding end 2 and the grounding portion 3, thereby adjusting the radiation wavelength.

[0034] See also Figure 1-3 In this embodiment, the grounding foam 31 is in the shape of a long strip, and the grounding foam 31 is arranged parallel to the length direction or the width direction of the radiating metal surface 11. The long strip of foam is conducive to full grounding, and the influence of clutter is smaller. At the same time, the long strip of grounding foam 31 can form a regular antenna clearance, and the antenna resonance area is clear, which is conducive to convenient adjustment of the resonance frequency.

[0035] See also Figure 1-3 In this embodiment, the feed end 2 protrudes from the edge of the radiation metal surface 11 and is arranged away from the ground portion 3, and the protrusion height of the feed end 2 is the same as the height of the side end surface 12. In addition to the role of exciting the resonant cavity, the feed end 2 can also play a certain supporting role for the radiation metal surface 11.

[0036] See also Figure 1 In one embodiment, the feeding end 2 includes a supporting portion 21 and a connecting portion 22, one end of the supporting portion 21 is vertically arranged at the edge of the radiating metal surface 11, and the other end is connected to the connecting portion 22, the connecting portion 22 is bent and arranged vertically to the supporting portion 21, and the connecting portion 22 is connected to the ground end of the mainboard 6 of the mobile device.

[0037] See also Figure 1-3 In this embodiment, at least one support portion 4 is provided on a side of the radiation metal surface 11 facing away from the ground portion 3, and the support portion 4 has the same height as the protrusion of the feeding end 2. The support portion 4 plays a certain supporting role on the radiation metal surface 11 to ensure the height of the resonant cavity and prevent the radiation metal surface 11 from collapsing under the impact of external force. The support portion 4 can be an insulating block, or the support portion 4 is a feeding point located at the edge of the radiation metal surface 11 to form a loop.

[0038] In this embodiment, the operating frequency band of the resonant cavity is the 2.4G WiFi band or the 5G WiFi band, and the distance between the ground portion 3 and the edge of the metal shell 1 close to the feeding end 2 is 1 / 4-1 / 2 of the resonant wavelength of the 5G WiFi band. The distance between the ground portion 3 and the edge of the metal shell 1 close to the feeding end 2 is used to control the radiation frequency band. To ensure the antenna efficiency, the distance is 1 / 4-1 / 2 of the resonant wavelength of the 5G WiFi band.

[0039] In one embodiment, the distance between the ground portion 3 and the edge of the metal shell 1 close to the feeding end 2 is 1 / 4 of the resonant wavelength of the 5G WiFi frequency band.

[0040] In this embodiment, the height of the resonant cavity is ≥1 mm. The height of the resonant cavity is limited to ensure that the antenna reaches resonance at the designed operating frequency, and maintains high gain and bandwidth while reducing the size of the antenna.

[0041] In one embodiment, the resonant cavity antenna for mobile devices has a length of 50 mm, a width of 28 mm, and a height of 1 mm for the resonant cavity, that is, the metal shell 1 is disposed on the mainboard 6, the distance between the metal shell 1 and the mainboard 6 is 1 mm, and the radiating metal surface 11 is supported by the feeding end 2, the side end surface 12, and the support portion 4 to maintain the height of the resonant cavity. By adjusting the position of the grounding foam 31, adjusting the distance between the grounding foam 31 and the edge of the radiating metal surface 11, and forming an antenna loop with the feeding end 2, the volume of the resonant cavity is controlled to control the antenna frequency band and bandwidth. In one embodiment, the distance between the grounding foam 31 and the edge of the radiating metal surface 11 is 3 mm.

[0042] Figure 4 This is the S11 parameter diagram of the resonant cavity antenna for mobile devices. Figure 4 The return loss in the 2.4G WiFi band and the return loss in the 5G WiFi band are both less than -5dB, with good impedance matching.

[0043] Figure 5 is a graph of antenna efficiency for resonant cavity antennas used in mobile devices, see Figure 5 The antenna efficiency in the 2.4G WiFi band is -3.8dB, and the antenna efficiency in the 5G WiFi band is (-7.2) to (-2.2)dB.

[0044] Example 2

[0045] This embodiment also provides a mobile device, Figure 6 is a diagram of the internal connections of a mobile device, see Figure 4 The mobile device includes a screen protection metal plate 5, a main board 6, a metal bottom plate 7 and the above-mentioned resonant cavity antenna for the mobile device; the screen protection metal plate 5 and the metal bottom plate 7 are connected to each other and enclosed to form an accommodating space; the main board 6 is located in the accommodating space and is arranged on the metal bottom plate 7; the metal shell 1 of the resonant cavity antenna for the mobile device is located in the accommodating space and is arranged on the metal bottom plate 7, and a resonant cavity is formed between the metal shell 1 and the main board 6; the feeding terminal 2 is electrically connected to the main board 6; the grounding part 3 is connected to the screen protection metal plate 5 of the mobile device.

[0046] In the mobile device provided in this embodiment, the screen protection metal plate 5 and the metal bottom plate 7 are enclosed to form an accommodation space, the mainboard 6 and the metal shell 1 are used to form a resonant cavity, and the grounding portion 3 is located on the metal shell 1 and is set away from the resonant cavity to short-circuit with the screen protection metal plate 5 to form an antenna loop. The resonance area of ​​the mobile device provided by the present invention is clear, and the resonant frequency and bandwidth can be adjusted by adjusting the position of the grounding portion 3. The optimization is convenient and fast, and it is suitable for mobile devices with all-metal bodies. The vertical projection of the metal shell 1 on the mainboard 6 forms an antenna clearance, which improves the antenna performance.

[0047] See also Figure 4 , the screen protection metal plate 5 and the metal bottom plate 7 of the mobile device are in a disassembled state. In one embodiment, the screen protection metal plate 5 is used to fit with the glass screen to play a protective role, and the screen protection metal plate 5 and the metal bottom plate 7 are buckled and fixed to form an accommodating space. The feed end 2 is connected to the radio frequency link on the mainboard 6 to achieve communication in the 2.4G WiFi band and the 5G WiFi band. The mobile device can be a mobile device with an all-metal body, such as a tablet, mobile phone, laptop computer, TV, etc., and the metal bottom plate 7 can be used as a back cover of the mobile device. The resonant cavity antenna for mobile devices takes up very little device space and can realize two communication frequency bands, which is conducive to reducing the number of antennas, reducing costs, and achieving wider bandwidth and better antenna efficiency. The size of mobile devices such as mobile phones can be reduced to 200mm*150mm*8mm, which is suitable for full-screen, all-metal designs.

[0048] The present invention is not limited to the above-mentioned embodiments. If various changes or modifications to the present invention do not depart from the spirit and scope of the present invention, and if these changes and modifications fall within the scope of the claims and equivalent technologies of the present invention, the present invention is also intended to include these changes and modifications.

Claims

1. A resonant cavity antenna for a mobile device, characterized in that: It includes a metal shell, a feeding terminal and a grounding portion; the metal shell is used to form a resonant cavity with the mainboard of the mobile device and is electrically connected to the mainboard ground of the mobile device; The feeding end is connected to the metal shell; The grounding portion is used to connect to the screen protection metal plate of the mobile device, and the grounding portion is arranged on a side of the metal shell away from the metal bottom plate, and the distance between the grounding portion and the edge of the metal shell close to the feeding end is 1 / 4-1 / 2 of the resonance wavelength; The metal shell is at least one of a copper shell, a steel shell and an aluminum shell.

2. The resonant cavity antenna for mobile device according to claim 1, characterized in that: The metal shell includes a radiating metal surface and a side end surface protruding from the edge of the radiating metal surface, the radiating metal surface is used to form a resonant cavity with the mainboard of the mobile device, and the side end surface is used to be electrically connected to the ground terminal of the mainboard of the mobile device; The grounding portion is located outside the resonant cavity and is arranged on one side of the radiating metal surface. The side end surface is protruded from one side of the radiating metal surface away from the grounding portion. The feeding end is arranged at the edge of the radiating metal surface.

3. The resonant cavity antenna for mobile device according to claim 2, characterized in that: The grounding part is grounding foam.

4. The resonant cavity antenna for mobile device according to claim 3, characterized in that: The grounding foam is in a long strip shape and is arranged parallel to the length direction or the width direction of the radiation metal surface.

5. The resonant cavity antenna for mobile device according to claim 2, characterized in that: The feeding end protrudes from the edge of the radiation metal surface and is arranged away from the grounding portion, and the protruding height of the feeding end is the same as the height of the side end surface.

6. The resonant cavity antenna for mobile device according to claim 5, characterized in that: A protrusion on a side of the radiation metal surface facing away from the grounding portion is provided with at least one supporting portion, and the supporting portion has the same height as the protrusion of the feeding end.

7. The resonant cavity antenna for mobile device according to claim 1, characterized in that: The operating frequency band of the resonant cavity is the 2.4G WiFi band or the 5G WiFi band, and the distance between the grounding portion and the edge of the metal shell close to the feeding end is 1 / 4-1 / 2 of the resonant wavelength of the 5G WiFi band.

8. The resonant cavity antenna for mobile device according to any one of claims 1 to 7, characterized in that: The height of the resonant cavity is ≥1 mm.

9. A mobile device, characterized in that: It comprises a screen protection metal plate, a main board, a metal bottom plate and a resonant cavity antenna for a mobile device as claimed in any one of claims 1 to 8; The screen protection metal plate and the metal bottom plate are connected to each other and enclose to form a containing space; The mainboard is located in the accommodating space and is arranged on the metal bottom plate; The metal shell of the resonant cavity antenna for mobile device is located in the accommodating space and is arranged on the main board, and a resonant cavity is formed between the metal shell and the metal bottom plate; The feeding end is electrically connected to the mainboard; The grounding portion is connected to a screen protection metal plate of the mobile device.

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