Resonant cavity antenna and electronic device

Abstract

The application provides a resonant cavity antenna and an electronic device, and relates to the field of communication. The polarization direction of the resonant cavity antenna is a vertical polarization direction, so that an orthogonal polarization direction can be formed with an antenna with a horizontal polarization direction in the electronic device, and the ability of the electronic device to receive or send signals is improved. The resonant cavity antenna comprises an antenna cavity, a first gap and a feeding portion. The antenna cavity is filled with an insulating medium. At least one side of a first surface of the antenna cavity is parallel to the length of a display screen of the electronic device. At least one side of a second surface of the antenna cavity is parallel to the length of the display screen. The plane in which the first surface is located and the plane in which the second surface is located intersect. The plane in which the first surface is located is parallel to the plane in which the display screen is located. The first gap is arranged on the second surface, and at least part of the first gap extends along the direction of the length of the display screen. The feeding portion is located inside the antenna cavity, and the feeding portion does not contact any surface of the antenna cavity.

Description

[0001] This application is a divisional application. The original application has the application number 202111204302.7 and the original application date is October 15, 2021. The entire contents of the original application are incorporated herein by reference. Technical Field

[0002] This application relates to the field of wireless communication, and more particularly to a resonant cavity antenna and electronic device. Background Technology

[0003] With the increasing popularity of handheld terminals, antenna technology is being applied to them more and more. Due to the trend of miniaturization and thinning of mobile terminals, the effective space for antenna areas is becoming smaller and smaller.

[0004] Currently, antennas in mobile terminals typically employ either a metal-frame design antenna (MDA) or a flexible printed circuit (FPC) antenna. However, the electric field direction of a floor-mounted MDA or FPC antenna is in the same plane as the floor, meaning the polarization direction of the mobile terminal's antenna is a horizontal polarization direction parallel to the floor, resulting in a single polarization direction for the antenna in the mobile terminal. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a resonant cavity antenna and an electronic device. The polarization direction of the resonant cavity antenna is vertical, which allows it to form an orthogonal polarization direction with an antenna in the horizontal polarization direction in the electronic device, thereby improving the electronic device's ability to receive or transmit signals.

[0006] In a first aspect, this application provides a resonant cavity antenna, comprising: an antenna cavity, a first slot, and a feed section;

[0007] The antenna cavity is a hexahedron containing at least five conductive walls and is filled with an insulating medium. The major axis of the resonant cavity antenna is parallel to the axis with the largest value in the electronic device. The first slot is opened on any surface containing the major axis and extends along the direction of the major axis. The feed section is located inside the antenna cavity and is connected to the radio frequency link of the electronic device. The distance between the feed section and the first slot is greater than zero.

[0008] For example, the antenna cavity can be a completely enclosed metal hexahedron or a metal hexahedron with one open end. The antenna cavity is filled with an insulating medium, enabling excitation of each surface when the feed section is connected to the RF link. A first slot is formed on any surface containing the long axis, and the first slot extends along the direction of the long axis, so that when the feed section is excited, an electric field can be generated around the long axis. Since the long axis is parallel to the axis with the largest value in the electronic device (for example, if a mobile phone is an electronic device, the axis with the largest value is the length of the mobile phone display screen; if a tablet computer is an electronic device, the axis with the largest value is the length of the tablet computer display screen), the resonant cavity antenna can form an electric field around the axis with the largest value in the electronic device. This electric field can cover the surface where the electronic device's display screen is located, as well as the surface opposite to the display screen; that is, the polarization direction of the resonant cavity antenna is a vertical polarization direction (i.e., perpendicular to the direction of the electronic device's display screen). Because the polarization direction of the resonant cavity antenna is a vertical polarization direction, combined with an antenna with a horizontal polarization direction in the electronic device, an orthogonal polarization direction is formed, improving the electronic device's ability to receive or transmit signals.

[0009] According to the first aspect, the resonant cavity antenna is deployed in a cavity formed by the metal back shell, metal frame and display screen of the electronic device. The height of the resonant cavity antenna is less than or equal to the thickness of the electronic device. The height axis is perpendicular to the long axis and the wide axis of the resonant cavity antenna. The long axis and the wide axis form the front, and the front is close to the display screen of the electronic device. The long axis and the height axis form the side. The wide axis and the height axis form a cross section.

[0010] In this way, since the resonant cavity antenna is deployed within the cavity formed by the metal back cover, metal frame, and display screen of the electronic device, it will not affect the shape of the electronic device. Because the high axis is perpendicular to the wide and long axes, the direction of the electric field generated within the antenna cavity can be further ensured, thus ensuring the stability of the antenna's polarization direction.

[0011] According to the first aspect, the resonant cavity antenna operates at TE. 0.5,0,1 In this mode, the range of the major axis of the antenna cavity is: [0.5λ - 0.5λ × 20%, 0.5λ + 0.5λ × 20%], the range of the broad axis is: [0.25λ - 0.25λ × 10%, 0.25λ + 0.25λ × 10%], and the height axis is less than 0.25λ, where λ is used to indicate the wavelength at which the resonant cavity antenna operates.

[0012] Thus, the resonant cavity antenna operates at TE. 0.5,0,1 The mode, λ, is used to indicate the wavelength at which the resonant cavity antenna operates, such that the electromagnetic wave generated by the resonant cavity antenna at half a wavelength forms a half-mode waveguide resonant cavity antenna.

[0013] According to the first aspect, the resonant cavity antenna operates at TE. 0.5,0, 0.5In this mode, the range of the major axis of the antenna cavity is: [0.25λ - 0.25λ × 20%, 0.25λ + 0.25λ × 20%], the range of the broad axis is: [0.25λ - 0.25λ × 10%, 0.25λ + 0.25λ × 10%], and the height axis is less than 0.25λ, where λ is used to indicate the wavelength at which the resonant cavity antenna operates.

[0014] Thus, the resonant cavity antenna operates at TE. 0.5,0,0.5 The mode, λ, indicates the wavelength at which the resonant cavity antenna operates, such that the antenna generates electromagnetic waves of 1 / 2.5 wavelengths and operates in the TE range. 0.5,0,0.5 The volume of the resonant cavity antenna in this mode is smaller than that operating in TE mode. 0.5,0,0.5 The volume of the resonant cavity in this mode. The reduction in the volume of the resonant cavity antenna makes its deployment more flexible.

[0015] According to the first aspect, the first gap is located on the front side and is adjacent to the side side.

[0016] In this way, the first gap is located on the front and adjacent to the side. That is, the first gap can be located between the display screen and the metal frame, which improves the energy of the electronic device to receive or transmit signals from the front. At the same time, the position of the first gap is concealed, which can reduce damage to the appearance of the electronic device.

[0017] According to the first aspect, gaps are simultaneously opened on the front and the side adjacent to the front, forming a first gap located between the front and the side.

[0018] In this way, the first slot is opened on the edge of the antenna cavity, which reduces the field strength on the front of the antenna and increases the field strength on the back, thus improving the flexibility of deploying the resonant cavity antenna.

[0019] According to the first aspect, the height range of the side where the first gap is located is: greater than 1 / 2 of the height axis and less than the height axis.

[0020] In this way, the height of the side can be gradually reduced, and the field strength on the back side can be gradually increased, further improving the flexibility of deploying the resonant cavity antenna.

[0021] According to the first aspect, the first gap is located in the middle of the side.

[0022] In this way, it is equivalent to a magnetic flow along the axial direction, with an omnidirectional pattern perpendicular to the high axial direction, and has the characteristics of low-profile vertical polarization, and the field strength on the front side is symmetrical to that on the back side.

[0023] According to the first aspect, the antenna cavity comprises, from bottom to top: a metal plate in the electronic device, three conductive foams, and a liquid crystal display (LCD) metal layer covering the three foams, with a display screen covering the LCD metal layer; the first foam and the second foam are located on the metal plate; the battery rib baffle of the electronic device is located on the metal plate, and the third foam is located on the battery rib baffle, with the third foam positioned close to the feed section, wherein the line connecting the first foam and the second foam is parallel to the battery rib baffle.

[0024] In this configuration, the metal plate is parallel to the battery reinforcement baffle. The first and second foams, located on the metal plate, form the long axis of the antenna cavity. The third foam is located on the battery reinforcement baffle, near the feed section. The third foam can eliminate clutter generated by the feed section, reducing interference. The LCD metal layer, metal plate, third foam, and either the first or second foam can form two closed conductive walls within the antenna cavity. The first, second, and third foams, along with the LCD metal layer, can form the front side (i.e., the conductive wall) near the display screen. Using foam to construct the antenna cavity eliminates the need for additional materials, reducing the space occupied within the electronic device's internal cavity and lowering the cost of constructing the resonant cavity antenna.

[0025] According to the first aspect, the antenna cavity also includes a fourth foam, which is located on the battery wall rib and is aligned with the second foam or the first foam.

[0026] In this way, the first and fourth foams are aligned, allowing the LCD metal layer, metal plate, first foam, and fourth foam to form a closed cross-section within the antenna cavity. Alternatively, if the second and fourth foams are aligned, the LCD metal layer, metal plate, second foam, and fourth foam can form a closed cross-section within the antenna cavity, and this cross-section is perpendicular to the LCD metal layer and metal plate, making this cross-section (i.e., the conductive wall) a strict boundary condition, reducing clutter generation.

[0027] According to the first aspect, the antenna cavity also includes a fifth foam; the fifth foam is located on the battery rib baffle; if the fourth foam is aligned with the second foam, then the fifth foam is aligned with the first foam; if the fourth foam is aligned with the first foam, then the fifth foam is aligned with the second foam.

[0028] Thus, if the fourth foam is aligned with the second foam and the fifth foam is aligned with the first foam, or if the fourth foam is aligned with the first foam and the fifth foam is aligned with the second foam, the two cross sections formed are both subject to strict boundary conditions, which allows the construction of a cuboid metal cavity with the minimum clutter amplitude, resulting in the optimal performance of the resonant cavity antenna.

[0029] According to the first aspect, if the resonant frequency of the resonant cavity is 2.45 GHz, the operating mode is TE. 0.5,0,1The two cross-sections of the resonant cavity antenna are closed conductive walls. The major axis of the resonant cavity antenna is 80mm, the width axis is 15.5mm, and the height axis is 6.5mm.

[0030] Thus, the resonant frequency of the resonant cavity is 2.45 GHz, and the operating mode is TE. 0.5,0,1 If the two cross sections of the resonant cavity antenna are set as closed conductive walls, the electromagnetic waves have standing wave characteristics inside the structure and radiation characteristics outside, and the radiation performance of the resonant cavity antenna is optimal.

[0031] According to the first aspect, the antenna cavity comprises, from bottom to top: a metal plate in the electronic device, at least two conductive foams, and a liquid crystal display (LCD) metal layer covering the two foams, with a display screen covering the LCD metal layer; the first foam is located on the metal plate; the battery reinforcement barrier of the electronic device is located on the metal plate, and the second foam is located on the battery reinforcement barrier, with the second foam positioned close to the feed section; the angle between the line connecting the first foam and the second foam and the battery reinforcement barrier is greater than 0 degrees and less than or equal to 45 degrees.

[0032] In this configuration, the metal plate is parallel to the battery reinforcement baffle, and the first foam is located on the metal plate, forming the long axis of the antenna cavity. The second foam is located on the battery reinforcement baffle, near the feed section. The second foam can be used to eliminate clutter generated by the feed section and reduce clutter interference. It should be noted that the metal plate of the electronic device is the metal plate inside the metal back shell. The LCD metal layer, the metal plate, and the second foam can form a closed conductive wall in the antenna cavity. Since only one closed conductive wall can be formed, the constructed antenna cavity has an open section at one end, reducing the volume of the antenna cavity, further reducing the material used to construct the resonant cavity antenna, reducing the space occupied within the cavity of the electronic device, and reducing the cost of constructing the resonant cavity antenna.

[0033] According to the first aspect, the antenna cavity also includes a third foam, which is located on the battery rib baffle and is aligned with the first foam.

[0034] In this way, the third foam, the LCD metal layer, the second foam, and the metal plate can form a closed conductive wall. If the third foam is not aligned with the first foam, the non-strict conductive wall formed by the third foam and the first foam reduces noise. If the third foam is aligned with the first foam, a strict boundary condition will be formed, which can further reduce the generation of noise.

[0035] According to the first aspect, the antenna cavity also includes a fourth foam, which is located on the battery rib baffle; if the third foam is aligned with the first foam, then the fourth foam is located between the second foam and the third foam; if the third foam is located between the first foam and the second foam, then the fourth foam is aligned with the first foam.

[0036] In this way, the second foam, the third foam, the fourth foam, the LCD metal layer, and the metal plate can form the side of the antenna cavity. The first foam and the third foam are aligned, or the first foam and the fourth foam are aligned, forming strict boundary conditions, which effectively reduces the generated clutter. At the same time, adding a foam can further reduce the amplitude of the clutter and improve the performance of the resonant cavity antenna.

[0037] According to the first aspect, if the resonant frequency of the resonant cavity is 2.45 GHz, the operating mode is TE. 0.5,0,0.5 The resonant cavity antenna includes an open cross-section, with a major axis of 45mm, a width axis of 15.5mm, and a height axis of 6.5mm.

[0038] Thus, the resonant frequency of the resonant cavity is 2.45 GHz, and the operating mode is TE. 0.5,0,1 The resonant cavity antenna configuration includes an open cross-section with a major axis of 45 mm, such that at a resonant frequency of 2.45 GHz and operating mode TE... 0.5,0,1 The radiation efficiency is optimal.

[0039] According to the first aspect, the gap between the display screen and the metal frame used to fill the gap with black glue is designated as the first gap.

[0040] In this way, the gap between the display screen and the metal frame in the electronic device, which is used to fill the gap with black glue, is used as the first gap, eliminating the need to create gaps in the metal frame or LCD metal layer, thus avoiding the problem of changing other structures in the electronic device.

[0041] According to the first aspect, if the first gap is opened on the side, then the gap opened in the metal frame shall be regarded as the first gap.

[0042] In this way, the metal plate in the metal frame is used as one side of the antenna cavity, and the first gap is opened in the metal frame to facilitate the antenna to radiate signals.

[0043] According to the first aspect, if the mode of the resonant cavity antenna is TE... 0.5,0,1 The power supply section is located at the point of greatest electric field in the long axis extension direction and is located near the first gap in the wide axis extension direction.

[0044] By positioning the feed section at a point of high electric field along the long axis, the feed section is more fully excited by the capacitive feed source. Furthermore, its position near the first gap along the wide axis improves the radiation efficiency of the resonant cavity antenna.

[0045] According to the first aspect, if the mode of the resonant cavity antenna is TE... 0.5,0,0.5The feed section is located at the point of greatest electric field and close to the opening in the long axis extension direction, while the feed section is located near the first gap in the wide axis extension direction.

[0046] In this way, the cross-section of the feed source near the opening, i.e., near the open-circuit boundary, allows the point with the largest electric field to be more fully excited by the capacitive feed source, thereby improving the bandwidth and radiation efficiency of the resonant cavity antenna. Secondly, this application provides an electronic device comprising: at least one frame antenna and a resonant cavity antenna as described in any of the first aspects; the frame antenna is located at a first corner or a second corner of the electronic device, the first corner being adjacent to the second corner; the resonant cavity antenna is located between a third corner and a fourth corner, the line connecting the third corner and the fourth corner being parallel to the line connecting the first corner and the second corner.

[0047] Thus, the electronic device also includes a frame antenna, which is positioned at the first or second corner, while the resonant cavity antenna is positioned between the third and fourth corners. This ensures that the frame antenna and the resonant cavity antenna are far apart, providing high isolation and preventing interference between them. Furthermore, the frame antenna, being a floor-mounted antenna, generates a horizontal polarization direction. When used in conjunction with the resonant cavity antenna, it enhances the signal reception and transmission power of the electronic device. For example, if the frame antenna is a Wi-Fi antenna operating at 2.45 GHz, and the resonant cavity antenna also operates at 2.45 GHz, the combined use of these two antennas results in a strong Wi-Fi signal from the electronic device.

[0048] According to the second aspect, if the resonant cavity antenna operates at TE... 0.5,0,0.5 In this mode, the resonant cavity antenna is located at the third or fourth corner.

[0049] Thus, since the resonant cavity antenna operates at TE 0.5,0,0.5 The pattern has an open cross-section, and the resonant cavity antenna is placed at the third or fourth corner, away from the frame antenna, which is beneficial for the resonant cavity antenna to radiate signals. Attached Figure Description

[0050] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0051] Figure 1 This is an illustrative diagram illustrating an application scenario of a tablet computer;

[0052] Figure 2 This is a schematic planar view of the unfolded metal frame in a tablet computer, as exemplarily shown.

[0053] Figure 3 This is a schematic diagram of the structure of a resonant cavity antenna provided in an embodiment of this application;

[0054] Figure 4 This is a three-dimensional schematic diagram of a resonant cavity antenna provided in an embodiment of this application;

[0055] Figure 5 This is an example of the far-field radiation pattern of a resonant cavity antenna;

[0056] Figure 6 This is a schematic diagram illustrating the positions of different feed sections in a resonant cavity antenna;

[0057] Figure 7 This is an exemplary diagram of the radiation efficiency of the power supply unit 303 at positions labeled ① to ⑥;

[0058] Figure 8 This is a schematic diagram illustrating the S-parameters and antenna radiation efficiency of the resonant cavity antenna when a distributed feed structure is used.

[0059] Figure 9 This is an exemplary schematic diagram showing the effect of the length of the major axis of the antenna cavity 301 on the TE mode;

[0060] Figure 10 This is an exemplary schematic diagram of the radiation efficiency of the resonant cavity antenna when the width of the first slit is reduced by 1 mm.

[0061] Figure 11 This is an exemplary schematic diagram of the radiation efficiency of the resonant cavity antenna when the height of the high axis in the antenna cavity is reduced by 1 mm.

[0062] Figure 12 This is an exemplary schematic diagram of the radiation efficiency of the resonant cavity antenna when the length of the wide axis in the antenna cavity is reduced by 5.5 mm.

[0063] Figure 13 This is a schematic diagram illustrating, by way of example, the effect of different media in the antenna cavity on the antenna performance of the resonant cavity antenna;

[0064] Figure 14 This is a top view of a tablet computer and a resonant cavity antenna provided in an embodiment of this application;

[0065] Figure 15 This is a schematic diagram of the structure of a power supply section provided in an embodiment of this application;

[0066] Figure 16 for Figure 14 Side view of a tablet computer and its resonant cavity antenna;

[0067] Figure 17 A schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with five foam elements is shown as an example.

[0068] Figure 18 A schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with four foam elements is shown as an example.

[0069] Figure 19 This is a schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with default foam 3042, as shown by example.

[0070] Figure 20 A schematic diagram illustrating the S-parameters and efficiency of another case where the resonant cavity antenna includes 5 foam units is shown as an example.

[0071] Figure 21 (1) is a schematic diagram of the electric field distribution inside a standard resonant cavity, which is an example shown.

[0072] Figure 21 (2) is a schematic diagram of the electric field distribution inside the resonant cavity antenna as an example;

[0073] Figure 22 The two-dimensional radiation pattern of the resonant cavity antenna is shown as an example.

[0074] Figure 23 (1) is a schematic diagram of the cross section of the antenna cavity when the height d1 of the side near the first slot is reduced by an exemplary amount;

[0075] Figure 23 (2) is a schematic diagram of the cross section of the antenna cavity when the height d2 of the side near the first slot is reduced by an example;

[0076] Figure 23 (3) is a schematic diagram of the cross section of the antenna cavity when the height d3 of the side near the first slot is reduced by an example;

[0077] Figure 23 (4) is a schematic diagram showing the first gap being opened in the middle of surface B1, as an example;

[0078] Figure 24 (1) is a schematic diagram of the coverage area of ​​the resonant cavity antenna in a three-dimensional radiation pattern when b1 is reduced by 0.5 mm, as exemplarily shown;

[0079] Figure 24 (2) is a schematic diagram of the coverage area of ​​the resonant cavity antenna in a three-dimensional radiation pattern when b1 is reduced by 1 mm, as exemplarily shown;

[0080] Figure 24 (3) is a schematic diagram of the coverage area of ​​the resonant cavity antenna in a three-dimensional radiation pattern when b1 is reduced by 2 mm, as exemplarily shown;

[0081] Figure 24 (4) is a schematic diagram of the coverage area of ​​the resonant cavity antenna in a three-dimensional radiation pattern when the first slot is opened in the middle of the B1 surface, as exemplarily shown;

[0082] Figure 25 This is a schematic diagram of the structure of a resonant cavity antenna as an example.

[0083] Figure 26 This is an example illustrating the two-dimensional radiation pattern of the resonant cavity antenna when the first slot is located in the middle of surface B1.

[0084] Figure 27 A three-dimensional schematic diagram of a resonant cavity antenna is shown as an example;

[0085] Figure 28 The resonant cavity antenna shown as an example uses TE 0.5,0,0.5 A schematic diagram showing the locations of different power supply units during the mode;

[0086] Figure 29 (1) is a three-dimensional radiation pattern of the resonant cavity antenna when the feed section is at position ①, as shown by example;

[0087] Figure 29 (2) is a three-dimensional radiation pattern of the resonant cavity antenna when the feed section is at position ②, as shown by example;

[0088] Figure 29 (3) is a three-dimensional radiation pattern of the resonant cavity antenna when the feed section is at position ③, as shown by example;

[0089] Figure 30 This is a schematic diagram illustrating the radiation efficiency of the resonant cavity antenna at different locations of the feed section, as an example.

[0090] Figure 31 A top view of a tablet computer and a resonant cavity antenna is shown as an example.

[0091] Figure 32a A schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with four foam elements is shown as an example.

[0092] Figure 32b This is a schematic diagram illustrating the S-parameters and radiation efficiency of a resonant cavity antenna with default foam 3046, as shown by example.

[0093] Figure 32c This is a schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with default foam 3047, as exemplarily shown.

[0094] Figure 32d This is a schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with default foam 3048, as exemplarily shown.

[0095] Figure 32e This is a schematic diagram illustrating the S-parameters and efficiency of the resonant cavity antenna with default foam 3046 and foam 3048 as an example.

[0096] Figure 32fA schematic diagram illustrating the S-parameters and efficiency of another resonant cavity antenna with four foam elements is shown as an example.

[0097] Figure 33 This is a two-dimensional radiation pattern of the resonant cavity antenna shown in this example;

[0098] Figure 34 This is a schematic diagram illustrating an exemplary deployment location of a resonant cavity antenna;

[0099] Figure 35 The resonant cavity antenna shown as an example operates at TE. 0.5,0,1 A schematic diagram showing the isolation between the antenna and other antennas in this mode.

[0100] Figure 36 Another resonant cavity antenna shown as an example operates at TE 0.5,0,1 A schematic diagram showing the isolation between the antenna and other antennas in this mode.

[0101] Figure 37 This is a schematic diagram illustrating an exemplary deployment location of a resonant cavity antenna;

[0102] Figure 38 An example of a resonant cavity antenna operating in TE 0.5,0,0.5 This diagram illustrates the isolation between the antenna and other antennas during mode.

[0103] Figure label:

[0104] 10-Tablet PC; 101-Metal frame; 102-FPC trace; 103-Antenna slot; 201-Signal strength indicator; 202-Antenna; 201'-Signal strength indicator; 20-Metal plate in tablet PC; 40-Battery in tablet PC; 50-Battery support wall in tablet PC; 60-LCD metal layer; 80-Free space; 90-Motherboard in tablet PC; 30-Resonant cavity antenna; 301-Antenna cavity; 302-First slot; 303-Feed section; 3041~3049-Foam; 3031-Feed structure; 3032-PCB board; 3033-Feed point. Detailed Implementation

[0105] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0106] In this article, the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0107] The terms "first" and "second," etc., used in the specification and claims of this application are used to distinguish different objects, not to describe a specific order of objects. For example, "first target object" and "second target object," etc., are used to distinguish different target objects, not to describe a specific order of target objects.

[0108] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0109] In the description of the embodiments in this application, unless otherwise stated, "multiple" means two or more. For example, multiple processing units means two or more processing units; multiple systems means two or more systems.

[0110] This application provides an electronic device. The electronic device includes a motherboard, a display screen, a battery, a mobile communication module, a wireless communication module, an antenna, etc. The motherboard may integrate a processor, internal memory, charging circuitry, etc. Of course, the electronic device may also include other components, and the motherboard may integrate other circuit structures; this application does not limit this.

[0111] A processor may include one or more processing units, such as an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, memory, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural network processing unit (NPU). Different processing units may be independent devices or integrated into one or more processors.

[0112] A GPU is a microprocessor for image processing, connected to the display and application processor. The GPU performs mathematical and geometric calculations and is used for graphics rendering. This allows the phone to achieve its display functions through the GPU, display, and application processor.

[0113] The charging circuit of an electronic device includes a power management circuit and a charging management circuit. The power management circuit connects the battery, the charging management circuit, and the processor. The charging management circuit receives charging input from the charger to charge the battery. While charging the battery, the charging management circuit can also supply power to the mobile phone via the power management circuit. The power management circuit receives input from the battery and / or the charging management module to supply power to the processor, internal memory, display, camera, antenna, mobile communication module, and wireless communication module, etc.

[0114] Wireless communication functionality in electronic devices can be achieved through antennas, mobile communication modules, wireless communication modules, modem processors, and baseband processors.

[0115] Antennas are used to transmit and receive electromagnetic wave signals. Each antenna in an electronic device can be used to cover one or more communication frequency bands. Different antennas can also be reused to improve antenna utilization. For example, an antenna can be reused as a diversity antenna for a wireless local area network. In some other embodiments, antennas can be used in conjunction with tuning switches.

[0116] Mobile communication modules can provide solutions for wireless communication applications in electronic devices, including 2G / 3G / 4G / 5G. A mobile communication module may include at least one filter, switch, power amplifier, low-noise amplifier (LNA), etc. The mobile communication module can receive electromagnetic waves via an antenna, filter and amplify the received electromagnetic waves, and transmit them to a modem processor for demodulation. The mobile communication module can also amplify the signal modulated by the modem processor and radiate it as electromagnetic waves via the antenna. In some embodiments, at least some functional modules of the mobile communication module may be housed within the processor. In some embodiments, at least some functional modules of the mobile communication module and at least some modules of the processor may be housed in the same device.

[0117] A modem processor may include a modulator and a demodulator. The modulator modulates a low-frequency baseband signal to be transmitted into a mid-to-high frequency signal. The demodulator demodulates a received electromagnetic wave signal into a low-frequency baseband signal. The demodulator then transmits the demodulated low-frequency baseband signal to a baseband processor for processing. After processing by the baseband processor, the low-frequency baseband signal is transmitted to an application processor. The application processor outputs sound signals through audio devices (such as speakers, receivers, etc.) or displays images or videos on a display screen. In some embodiments, the modem processor may be a separate device. In other embodiments, the modem processor may be independent of the processor and housed within the same device as the mobile communication module or other functional modules.

[0118] Wireless communication modules can provide solutions for wireless communication applications in electronic devices, including wireless local area networks (WLANs) (such as wireless fidelity (Wi-Fi) networks), Bluetooth (BT), global navigation satellite system (GNSS), frequency modulation (FM), near field communication (NFC), and infrared (IR) technologies. A wireless communication module can be one or more devices integrating at least one communication processing module. The wireless communication module receives electromagnetic waves via an antenna, modulates and filters the electromagnetic wave signal, and sends the processed signal to a processor. The wireless communication module can also receive signals to be transmitted from the processor, modulate and amplify them, and then convert them into electromagnetic waves for radiation via the antenna.

[0119] In some embodiments, one antenna of the electronic device is coupled to a mobile communication module, and another antenna is coupled to a wireless communication module, enabling the electronic device to communicate with networks and other devices via wireless communication technology.

[0120] In this application embodiment, the electronic device is a tablet computer as an example. Figure 1 This is a schematic diagram illustrating an application scenario of a tablet computer. For example... Figure 1 As shown, the horizontal plane can be Figure 1 In the XOY plane, the user places the tablet 1 vertically on a table, which is parallel to the horizontal plane. The minor axis e of the tablet 1 is... Figure 1 The Z-axis in the coordinate system is parallel, and the major axis f is parallel to... Figure 1The X-axis in the coordinate system is parallel. The plane on which the display screen of tablet computer 1 is located is the plane formed by the major axis f and the minor axis e of tablet computer 1. When tablet computer 1 is perpendicular to the desktop, the display screen of tablet computer 1 is also perpendicular to the horizontal plane. It is understood that the angle between the display screen of tablet computer 1 and the horizontal plane is not limited to 90 degrees, and the range of the angle can also be between 30 and 150 degrees. This example does not limit the degree of the angle. The antenna in tablet computer 1 is usually an MDA or FPC antenna surrounding the floor of tablet computer 1. Optionally, the floor of tablet computer 1 may include the motherboard of tablet computer 1; in other examples, the floor of tablet computer 1 may also include an aluminum alloy plate on which the motherboard is deployed, which will not be listed in this example. Since the floor of tablet computer 1 is parallel to the display screen, the FPC antenna in tablet computer 1 will generate an angle perpendicular to the horizontal plane (e.g., Figure 1 The electric field of the FPC antenna of the tablet computer 1 in the XOY plane is perpendicular to the XOY plane.

[0121] The user places router 1 on the ground parallel to the horizontal plane, and the antenna 202 in router 1 is perpendicular to the horizontal ground (i.e., as shown). Figure 1 As shown, the antenna 202 of router 1 and Figure 1 The Z-axis is parallel to the horizontal plane (e.g., the antenna 202 of router 1 generates an angle perpendicular to the horizontal plane). Figure 1 The electric field in the XOY plane, i.e., the polarization direction of antenna 202 of router 1, is perpendicular to the XOY plane. It can be seen that when tablet 1 is placed vertically on a horizontal plane, the polarization direction of the antenna in tablet 1 is the same as that of antenna 202 in router 1. That is, the polarization directions of the antenna in tablet 1 and antenna 202 in router 1 are matched, indicating that tablet 1 has a strong signal reception capability. In this example, a signal strength indicator 201 is displayed on the interface of tablet 1. This signal strength indicator 201 is used to indicate the strength of the signal received by tablet 1. For example, if the signal strength indicator 201 shows a full bar (i.e., 3 bars), it indicates that the received signal strength of tablet 1 is strong, and the network latency of the tablet is low, such as a game latency of less than 50ms.

[0122] like Figure 1 As shown by the middle arrow, the user places tablet 1 horizontally on the table (i.e., the screen of tablet 1 is parallel to the horizontal plane). The electric field direction generated by the antenna in tablet 1 is parallel to the XOY plane, meaning the polarization direction of the antenna in tablet 1 is parallel to the XOY plane. The user has not changed the direction of the antenna in router 1; the polarization direction of the antenna in router 1 remains perpendicular to the XOY plane. The polarization direction of the antenna in tablet 1 is inconsistent with that of the antenna in router 1, meaning the polarization directions of the antennas in tablet 1 and router 1 do not match, resulting in a weakened signal reception capability for tablet 1. Figure 1 In the interface of tablet computer 1, the signal strength indicator 201' shows two bars, indicating a game latency of 100ms. Tablet computer 1 receives a stronger signal when perpendicular to the table than when parallel to it. Therefore, changes in the tablet computer 1's position will alter its signal reception capability, resulting in a decrease in signal strength.

[0123] The tablet computer 1 includes a display screen, a metal back cover parallel to and facing away from the display screen, and a metal frame disposed between the metal back cover and the display screen. The antenna of the electronic device is typically an MDA or FPC antenna, which is deployed within the metal frame. This example uses an FPC antenna that surrounds the floor as an example. Figure 2 This is a schematic planar view of the unfolded metal frame in a tablet computer 1, as exemplarily shown.

[0124] like Figure 2 As shown, an FPC antenna 102 is deployed on a metal frame 101. The metal frame 101 has an opening to form an antenna slot 103 for the FPC antenna. The FPC antenna 102 includes a radiating element coupled to the metal frame 101 and a feed pin connecting the radiating element to the radio frequency output terminal of the tablet computer 1. The metal frame 101 is electrically connected to the reference ground of the tablet computer 1. A wireless communication module or a mobile communication module transmits signals to the FPC antenna 102, which radiates electromagnetic wave signals through the antenna slot 103.

[0125] In this example, the FPC antenna in tablet PC 1 surrounds the floor, and the polarization direction of the FPC antenna 102 is parallel to the display screen, exhibiting a single polarization direction. When the pose of tablet PC 1 changes, the signal receiving capability of the antenna in tablet PC 1 changes, such as... Figure 1 The tablet computer 1 is now placed parallel to the target plane, causing a mismatch in polarization direction with the antenna 202 in router 1. This weakens the tablet's signal reception capability, affecting the user's network access experience. Optionally, the network can be Wi-Fi, Bluetooth, 4G / 5G, etc. Furthermore, current electronic devices (such as mobile phones and tablets) employ an all-metal back cover industrial design (ID), preventing antennas surrounding the floor from radiating signals outwards through the back cover.

[0126] Based on this, this application provides a resonant cavity antenna. Figure 3 This is a schematic diagram illustrating the structure of a resonant cavity antenna as an example. The structure of this resonant cavity antenna is as follows: Figure 3 As shown, the antenna cavity 301 includes a resonant cavity, a first slot 302, and a feed section 303 located within the antenna cavity 301.

[0127] Electromagnetic waves exhibit standing wave characteristics inside the resonant cavity antenna and radiation characteristics outside, thus possessing antenna characteristics. In this example, the antenna cavity 301 can be a rectangular waveguide. A rectangular waveguide is typically a regular metal waveguide made of metal, with a rectangular cross-section, and its interior is filled with an insulating medium.

[0128] The resonant cavity antenna includes six metal surfaces, forming a shape like... Figure 3 The antenna cavity 301 shown has a cross-section parallel to... Figure 3 The XOY plane in the coordinate system. For example... Figure 3 As shown, the first gap 302 can be disposed on the C1 surface. The C1 surface is parallel to... Figure 3 The XOZ plane in the coordinate system. The first gap 302 can also be positioned on the B1 plane, which is parallel to... Figure 3 The YOZ plane in the coordinate system. The first gap 302 can also be located in the boundary region between the B1 and C1 planes, for example, by reducing the minor axis c11 in the C1 plane that is close to the B1 plane. This minor axis c11 is along... Figure 3 Extending along the X direction in the coordinate system; simultaneously decreasing the minor axis b11 in the B1 plane that is close to the C1 plane, which b11 along... Figure 3 Extending in the Y direction of the coordinate system. The width of this first gap can be set according to the actual application.

[0129] The power supply section 303 is located inside the antenna cavity 301. The power supply section 303 does not contact the first gap 302. The power supply section is connected to the RF link of the motherboard through an externally pulled RF coaxial transmission line (i.e., cable line).

[0130] The radio frequency signal in the motherboard's radio frequency link is fed into the power supply section 303 via the cable. The power supply section 303 excites the half-mode waveguide resonant mode of the resonant cavity antenna, and transmits electromagnetic waves through the radiating aperture (i.e., the first slot 302). Alternatively, electromagnetic waves can be received through the radiating aperture.

[0131] In one possible embodiment, this application specifically illustrates the resonant cavity antenna with the first slot disposed on the C1 surface as an example.

[0132] Figure 4 This is a three-dimensional schematic diagram of a resonant cavity antenna 30 as an example. Figure 4 As shown, the axis extending along the Z-direction in this resonant cavity antenna is taken as the major axis and denoted as L. The axis extending along the Z-direction in this resonant cavity antenna... Figure 4 The axis extending in the X direction is taken as the width axis and denoted as a. In this resonant cavity antenna, along... Figure 4 The axis extending in the Y direction is designated as the height axis, denoted as b. The first gap is located on surface C1, and the width of this first gap 302 is denoted as w. Figure 4The diagonal lines filling the space indicate the insulating medium in the resonant cavity antenna. Both cross sections a and b of the resonant cavity antenna 30 are metallic surfaces.

[0133] Within the antenna cavity 301 (also called the resonant cavity), there exist TE and TM modes. There is no unique longitudinal direction (i.e., propagation direction) within the antenna cavity 301; therefore, the names of the TE and TM modes are not unique. For example, the "propagation direction" is referenced to the Z-axis. Because of the conductor walls at z=0 and z=L, electromagnetic waves are reflected between them, forming standing waves; therefore, there is no wave propagation within the antenna cavity 301. For TE... m,n,p In this mode, either m or n can be zero (m and n cannot be zero simultaneously), and p cannot be zero. Based on the size of the electronic device, the high axis b is the minimum dimension constraining the antenna cavity. Limited by the cross-sectional dimensions, in sub-6G, there is no half-wavelength in height, and there are electric field lines within the cross-section; therefore, TE... m,0,p In the pattern, m and p are integers.

[0134] In this example, because a first slot is provided in the resonant cavity antenna, the wavelength of the resonant cavity becomes 1 / 4 wavelength, and the TE mode can be TE. 0.5,0,1 model.

[0135] For TM m，n，p Pattern and TE m，n，p The mode, the expression for the resonant frequency of this resonant cavity is:

[0136] Formula (1);

[0137] Where m indicates the number of half-standing waves distributed in the X direction, n indicates the number of half-standing waves distributed in the Y direction, and p indicates the number of half-standing waves distributed in the Z direction. and It is a constant. w mnp Used to indicate the speed of light. k mnp Used to indicate constants. a Indicates the value of the wide axis of the resonant cavity. b Indicates the value of the high axis of the resonant cavity. l This indicates the value of the major axis of the resonant cavity. According to formula (1), the value of the major axis of the resonant cavity is... a , b , l They are interconnected. For example, the dielectric medium inside the resonant cavity antenna is the same, and the resonant cavity antenna operates at TE. 0.5,0,1 In this case, the resonant cavity antenna a The value range can be [0.25λ - 0.25λ × 10%, 0.25λ + 0.25λ × 10%], bThe value is less than 0.25λ. l The value range can be [0.5λ - 0.5λ × 20%, 0.5λ + 0.5λ × 20%], where λ indicates the wavelength at which the resonant cavity antenna operates. In another example, the dielectric medium inside the resonant cavity antenna is the same, and the resonant cavity antenna operates at TE. 0.5,0,0.5 In this case, the resonant cavity antenna a The value range can be [0.25λ - 0.25λ × 10%, 0.25λ + 0.25λ × 10%], b The value is less than 0.25λ. l The value range can be [0.25λ - 0.25λ × 20%, 0.25λ + 0.25λ × 20%], where λ is used to indicate the wavelength at which the resonant cavity antenna operates.

[0138] It should be noted that the size of the resonant cavity antenna is set according to its resonant frequency. For example, at a resonant frequency of 2.45 GHz and operating mode TE... 0.5,0,1 The resonant cavity antenna has two closed conductive walls at both cross-sections. Its major axis is 80mm, its major axis is 15.5mm, and its height axis is 6.5mm. If the resonant frequency of the resonant cavity antenna is 2.45GHz, and its operating mode is TE... 0.5,0,0.5 Therefore, the major axis of the resonant cavity antenna is 45mm, the width axis is 15.5mm, and the height axis is 6.5mm.

[0139] In this example, a TE resonant cavity antenna is used. 0.5,0,1 The following explanation uses the mode operation as an example.

[0140] The far-field radiation pattern of the resonant cavity antenna in this example is as follows: Figure 5 As shown. Figure 5 The rectangle in the diagram represents the side view of the tablet computer (i.e., the surface formed by the f-axis and the height of the tablet computer). Since the first gap is located on surface C1... Figure 5 The electric field strength of the external electric field of the resonant cavity antenna on the C1 surface is greater than that on the surface away from the C1 surface. Due to the edge effect, there are still electric field lines that bypass the axis at the junction of the B1 and C1 surfaces of the tablet computer. By inducing the potential difference, the electric field of the metal back shell of the tablet computer is excited, thus achieving field coverage on the back of the tablet computer.

[0141] The following is combined Figures 6-8 Explain the impact of the feed section location on the antenna performance of the resonant cavity antenna.

[0142] Figure 6 The positions of different feed sections in this resonant cavity antenna are shown as an example. Figure 6 The image shows a top view of the tablet computer and a top view of the resonant cavity antenna. Figure 6A1 and A2 are top views of two cross-sections (i.e., the planes formed by the width axis and height axis) of the resonant cavity antenna. In practice, these cross-sections can have a certain thickness, such as... Figure 6 In this context, A1 and A2 are rectangular. The width of the first gap 302 is w. The power supply units 303 are respectively located at positions labeled ① to ⑥. For example... Figure 6 As shown, labels ① to ③ are all located at the middle of the long axis L of the resonant cavity antenna, and labels 4 to 6 are all located at a cross-section close to the resonant cavity antenna.

[0143] The following is combined with Figure 4 and Figure 6 The positions of the six labels are explained separately. In this example, refer to... Figure 4 The coordinate system is shown. Label ① has a value of 1 / 2L in the Z direction, 0 in the Y direction, and a value in the X direction that is greater than 0 and less than w. Label ② has a value of 1 / 2L in the Z direction, 0 in the Y direction, and a value in the X direction that is greater than w and closer to the first gap in the X direction. Label ③ has a value of 1 / 2L in the Z direction, 0 in the Y direction, and farther from the first gap in the X direction. Label ④ has a value in the Z direction that is greater than 1 / 2L and less than or equal to L, 0 in the Y direction, and a value in the X direction that is greater than 0 and less than w. Label ⑤ has a value in the Z direction that is greater than 1 / 2L and less than or equal to L, 0 in the Y direction, and a value in the X direction that is closer to the first gap and greater than w. Label ⑥ has a value in the Z direction that is greater than 1 / 2L and less than or equal to L, 0 in the Y direction, and farther from the first gap in the X direction.

[0144] Figure 7 The radiation efficiency diagrams of the power supply unit 303 at positions labeled ① to ⑥ are shown for example. Figure 7 The resonant cavity antenna dimensions in this example are a=15.5mm, b=6.5mm, L=80mm, and w=3mm. Figure 7 As shown, the horizontal axis of this radiation efficiency graph represents the resonant frequency (in GHz), and the vertical axis represents the antenna radiation efficiency (in dB). When the feed unit 303 is located at position ①, the radiation efficiency curve of the antenna is as follows. Figure 7As indicated by reference numeral ①. When the feed unit 303 is located at position ①, the peak radiation efficiency is at position 1 of triangle 1 (i.e., 2.4782 GHz). When the feed unit 303 is located at position ②, the peak radiation efficiency is at position 1 of triangle 1 (i.e., 2.4782 GHz). When the feed unit 303 is located at position ③, the peak radiation efficiency is at position 1 of triangle 1 (i.e., 2.4782 GHz). The bandwidth of the feed unit 303 at position ② is greater than the bandwidth of the feed unit 303 at positions ① and ②. When the feed unit is located at position ④, the peak radiation efficiency is at position 4 of triangle 4 (i.e., 2.4244 GHz). When the feed unit 303 is located at position ⑤, the peak radiation efficiency is at position 2 of triangle 2 (i.e., 2.4517 GHz). When the feed unit is located at position ⑥, the peak radiation efficiency is at position 3 of triangle 3 (i.e., 2.44 GHz). The radiation efficiency of the feed section located at positions ④, ⑤, and ⑥ is lower than that of the feed section 303 located at positions ①, ②, and ③. Since the bandwidth of the feed section 303 at positions ① and ③ is small, meaning that position ② has the highest radiation efficiency and widest bandwidth among the six positions, and is also a point with a large electric field, the feed section 303 can be deployed at this position. Deploying the feed section at a point with a large electric field is beneficial for antenna signal transmission and reception. Optionally, in this example, the resonant cavity antenna operates at TE... 0.5，0，1 In the normal mode, the power supply unit 303 can be set at position ②.

[0145] Optionally, in this example, the feed section can employ a distributed feed structure. A distributed feed structure adjusts the antenna capacitance and inductance by modifying the shape of the feed structure.

[0146] Should Figure 8 This is a schematic diagram illustrating the S-parameters and antenna radiation efficiency of the resonant cavity antenna using a distributed feed structure, as exemplarily shown. For example, Figure 8 S1,1 is used to indicate that the resonant cavity antenna is located as shown in the image. Figure 6 The resonance curve at position ② shows that the resonant frequency of the resonant cavity antenna is 2.445 GHz. Figure 8 The symbol Rad indicates the antenna's radiation efficiency curve. Figure 8 The symbol Tot indicates the system efficiency curve of the antenna. The peak system efficiency and radiation efficiency of this resonant cavity antenna are both located at 2.4597 GHz. Figure 8 As can be seen from the S-parameter curve and the radiation efficiency diagram of the antenna, the radiation efficiency of the distributed feeding structure is consistent with that of the traditional adjustment device (such as adjusting capacitors and inductors).

[0147] In one embodiment, the antenna performance of a resonant cavity antenna is related to the size and shape of the resonant cavity antenna. The size information of the resonant cavity antenna includes information about its major axis (i.e., L), its width axis (i.e., a), and its height axis (i.e., b).

[0148] Figure 9 This is a schematic diagram illustrating the effect of the length of the major axis (i.e., L) of the antenna cavity 301 on the TE mode.

[0149] Figure 9 The tablet computer 1 is placed parallel to a horizontal plane (i.e., the screen of the tablet computer 1 is parallel to the horizontal plane). Figure 9 A top view of the tablet computer 1 is shown. The tablet computer 1 measures 276 (f-axis) mm × 187 (e-axis) mm. In this example, the resonant cavity antenna is used with a = 15.5 mm, b = 6.5 mm, and w = 3 mm to illustrate the effect of L on the antenna performance of the resonant cavity antenna.

[0150] This example combines Figure 9 The three-dimensional radiation patterns of the resonant cavity antenna are shown for four different values ​​of L, illustrating the effect of L on antenna performance.

[0151] Figure 9 (1) The three-dimensional radiation pattern of the resonant cavity antenna when L=40mm in the antenna cavity 301. Figure 9 As shown in (1), the directivity of this resonant cavity antenna is 6.30 dBi. Figure 9 (1) The resonant cavity antenna uses a TE lower than TE 0.5,0,1 The mode covers 2.45GHz.

[0152] Figure 9 (2) The three-dimensional radiation pattern of the resonant cavity antenna when L=80mm in the antenna cavity 301. Figure 9 As shown in (2), the directivity of this resonant cavity antenna is 6.62 dBi. Figure 9 (2) The resonant cavity antenna uses TE 0.5,0,1 The mode covers 2.45GHz. Figure 9 (2) The directivity of the resonant cavity antenna is weaker than Figure 9 (1) Directivity of the resonant cavity antenna.

[0153] Figure 9 (3) The three-dimensional radiation pattern of the resonant cavity antenna when L=160mm in the antenna cavity 301. Figure 9 As shown in (3), the directivity coefficient of this resonant cavity antenna is 8.01 dBi. Figure 9 (3) The resonant cavity antenna uses TE 0.5,0,2 The mode covers 2.45GHz. Figure 9 (3) The directivity of the resonant cavity antenna is weaker than Figure 9 (2) Directivity of the resonant cavity antenna.

[0154] Figure 9 (4) The three-dimensional radiation pattern of the resonant cavity antenna when L=240mm in the antenna cavity 301. Figure 9 As shown in (4), the directivity of this resonant cavity antenna is 8.60 dBi. Figure 9 (4) The resonant cavity antenna uses TE 0.5,0,3 The mode covers 2.45GHz. Figure 9 (4) The directivity of the resonant cavity antenna is weaker than Figure 9 (3) Directivity of the resonant cavity antenna.

[0155] from Figure 9 From (1) to (4), it can be seen that the directivity of the resonant cavity antenna is optimal when L = 40 mm. Different values ​​of L require different TE modes to cover 2.45 GHz. Furthermore, as the length of L increases, the operating mode of the resonant cavity antenna gradually changes from below the TE range. 0.5,0,1 Model to TE 0.5,0,3 Mode switching, i.e., the transition from the base mode to the secondary and tertiary modes, gradually deteriorates the directivity of the resonant cavity antenna. When the resonant cavity antenna covers 2.45 GHz, it achieves maximum L and optimal directivity when operating in the base mode; however, the directivity deteriorates to varying degrees when operating in higher-order modes.

[0156] This example combines Figure 7 and Figure 10 Explain the impact of reducing the width of the first slot in the resonant cavity antenna on the antenna performance. Figure 7 The medium resonant cavity antenna is taken as an example with a=15.5mm, b=6.5mm, L=80mm and w=3mm. Figure 10 This is a schematic diagram illustrating the radiation efficiency of the resonant cavity antenna when the width of the first slot is reduced by 1 mm (i.e., w = 2 mm). Figure 10 In the medium resonant cavity antenna, a=15.5mm, b=6.5mm, L=80mm, and w=2mm.

[0157] like Figure 10 As shown, when the dimensions of the resonant cavity antenna are a=15.5mm, b=6.5mm, L=80mm and w=2mm, the Rad symbol is used to indicate the radiation efficiency curve of the resonant cavity antenna. The peak of the Rad curve is located at triangle number 6. Figure 10 The triangle labeled 6 (i.e., 2.44 GHz) and Figure 7 Compared to the mid-triangle marker 1 (i.e., 2.47 GHz), the peak radiation efficiency of this resonant cavity antenna is 30 MHz lower. Figure 10 The label Tot indicates the system efficiency of the resonant cavity antenna. The label S1,1 indicates that the resonant cavity antenna is located at... Figure 6 The resonance curve at position ②. Labels S2,2 indicate the resonance curve of the Bluetooth antenna in tablet PC 1. Labels S1,2 indicate the isolation curve between the Bluetooth antenna in tablet PC 1 and the resonant cavity antenna in this example.

[0158] This example combines Figure 7 and Figure 11 Explain the impact of decreasing the height of the high axis (i.e., b) in a resonant cavity antenna on antenna performance. Figure 7 Taking a medium resonant cavity antenna with a=15.5mm, b=6.5mm, L=80mm and w=3mm as an example. Figure 11 This is a schematic diagram illustrating the radiation efficiency of the resonant cavity antenna when the height of b is reduced by 1 mm (i.e., b = 5.5 mm). Figure 11 In the medium resonant cavity antenna, a=15.5mm, b=5.5mm, L=80mm, and w=3mm.

[0159] like Figure 11 As shown, the curve labeled Rad indicates the radiation efficiency of the resonant cavity antenna. The peak of the Rad curve is located at triangle number 6. Figure 11 The triangle labeled 6 (i.e., 2.4746 GHz) and Figure 7 Compared to the mid-triangle marker 1 (i.e., 2.47 GHz), the peak radiation efficiency of this resonant cavity antenna is about 50 MHz higher. Figure 11 The label Tot indicates the system efficiency of the resonant cavity antenna. The label S1,1 indicates that the resonant cavity antenna is located at... Figure 6 The resonance curve at position ②. Labels S2,2 indicate the resonance curve of the Bluetooth antenna in tablet PC 1. Labels S1,2 indicate the isolation curve between the Bluetooth antenna in tablet PC 1 and the resonant cavity antenna in this example.

[0160] This example combines Figure 7 and Figure 12 Explain the impact of reducing the length of the wide a-axis (i.e., the length of the resonant cavity antenna) on the antenna performance. Figure 7 In the medium resonant cavity antenna, a=15.5mm, b=6.5mm, L=80mm, and w=3mm. Figure 12 This is a schematic diagram illustrating the radiation efficiency of the resonant cavity antenna when the length of 'a' is reduced by 5.5 mm (i.e., a = 10 mm). Figure 12 The resonant cavity antenna has a = 10 mm, b = 6.5 mm, L = 80 mm, and w = 3 mm.

[0161] like Figure 12 As shown, the curve labeled Rad indicates the radiation efficiency of this resonant cavity antenna, with a peak value at 3.5 GHz. Figure 7 Compared to the middle triangle marker 1 (i.e., 2.47 GHz), the peak radiation efficiency of this resonant cavity antenna becomes 3.5 GHz. Figure 12 The label Tot indicates the system efficiency of the resonant cavity antenna. The label S1,1STD indicates that the resonant cavity antenna is located in... Figure 6 The resonance curve at position ②. Labels S2,2STD indicate the resonance curve of the Bluetooth antenna in tablet PC 1. Labels S1,2STD indicate the isolation curve between the Bluetooth antenna in tablet PC 1 and the resonant cavity antenna in this example.

[0162] In this example, by analyzing the width of the first slot and the effects of L, a, and b on antenna performance in the resonant cavity antenna, combined with the resonant cavity mode calculation method, it can be determined that L, b, and a in the resonant cavity antenna determine the operating frequency of different modes of the antenna. Under the conditions of sub-6GHz (i.e., the 3GHz~4GHz band) and current terminal limitations on the high axis (i.e., b), the change in the width w has a relatively small impact on the resonance. The resonant frequency of the resonant cavity antenna (i.e., the peak value of the fundamental mode radiation efficiency) is mainly determined by L and a, and has a significant impact on antenna performance.

[0163] In this example, when the resonant cavity antenna uses the fundamental mode (i.e. When covering 2.45 GHz, optionally, the L of the resonant cavity antenna can be 80 mm, the wide axis (i.e., a) can be 15.5 mm, the high axis (i.e., b) can be 6.5 mm, and the width of the first slot (i.e., w) can be 3 mm. Using this size makes the antenna performance of the resonant cavity antenna optimal.

[0164] This example combines Figure 13 Explain the influence of different media in the antenna cavity on the antenna performance of the resonant cavity antenna. Figure 13 The medium resonant cavity antenna is illustrated using a=15.5mm, b=6.5mm, L=80mm and w=3mm as examples. Figure 13 The curve represented by triangle 3 shows the radiation efficiency when the lossy dielectric is FR-4 (i.e., loss tangent El. tand. = 0.05). The curve represented by triangle 2 shows the radiation efficiency when the lossy dielectric is PLA plastic (i.e., El. tand. = 0.0092). The curve represented by triangle 1 shows the radiation efficiency when the loss tangent is 0.005 (i.e., El. tand. = 0.005). When the lossy dielectric is changed from FR-4 to PLA plastic, the radiation efficiency of this resonant cavity antenna increases by 2.5 dB. When the loss tangent is further reduced to 0.005, the radiation efficiency of this resonant cavity antenna further increases by 0.5 dB.

[0165] In this example, the dielectric constant affects the number of wavelengths per unit length. With a loss tangent between 0.005 and 0.05, the radiation efficiency and bandwidth of this resonant cavity antenna can meet the frequency band requirements of current terminals (such as tablets). That is, the dielectric in this resonant cavity antenna can be FR-4, PLA plastic, or other dielectrics with a loss tangent between 0.005 and 0.05.

[0166] In this example, the dimensions of the resonant cavity antenna can be w=3mm, a=15.5mm, b=6.5mm, and L=80mm. The constructed resonant cavity antenna is deployed within the cavity formed by the metal back cover, metal frame, and display screen of the tablet computer. Optionally, to save space and material for the resonant cavity antenna deployment, the embodiments of this application employ... Figure 14 The resonant cavity antenna structure shown is shown.

[0167] Figure 14 This is a top view of an exemplary tablet computer and its resonant cavity antenna. The tablet computer is placed horizontally on a horizontal table. Figure 14 In the diagram, reference numeral 10 indicates the tablet computer, reference numeral 40 indicates the battery in the tablet computer, reference numeral 50 indicates the battery retaining wall in the tablet computer, reference numeral 20 indicates the metal plate in the tablet computer, reference numeral 30 indicates the resonant cavity antenna, and reference numeral 80 indicates free space. The resonant cavity antenna includes: a feed section 303, foam (such as...) Figure 14 Medium foam 3041~foam 3045) and first gap 302 ( Figure 14 (The gap and display screen are not shown). The antenna cavity 301 of this resonant cavity antenna consists of foam, a metal plate, and an LCD metal layer covering the foam. Figure 14 (The LCD metal layer is not shown). Foams 3041 to 3045 are conductive foams used to construct the boundary conditions of the resonant cavity antenna. The lengths of foams 3041 to 3043 serve as the major axis L of the resonant cavity antenna; similarly, the lengths of foams 3044 (if it is the first foam) to 3045 (if it is the second foam) serve as the other major axis L of the resonant cavity antenna. It can be understood that... Figure 14This is a top view. The line connecting foams 3044 and 3045 is parallel to one side wall of the metal frame. For example, the side wall between metal plate 20 and free space 80 is the side wall of the metal frame, which can serve as one side of the antenna cavity (i.e., the side formed by the L-axis and the height axis). Foams 3041, 3044, 3043, and 3045 together form the short-circuit boundaries at both ends of the resonant cavity antenna (i.e., the boundary formed by the combination of the wide axis a and the height axis b). In this example, the wide axis a formed by foams 3043 and 3045 is perpendicular to the long axis L formed by foams 3041 and 3043, creating a strict boundary condition. It can be understood that the wide axis a formed by foams 3041 and 3044 is perpendicular to the long axis L formed by foams 3041 and 3043, creating a strict boundary condition.

[0168] Foams 3044 and 3045 are crucial for constructing the fundamental mode radiation aperture and are indispensable. Foam 3042 (e.g., the third foam) is positioned parallel to the feed section. The feed section is deployed at a point of high electric field, and foam 3042, parallel to the feed section 303, can be used to eliminate clutter generated by the feed section 303. Optionally, foams 3041 (e.g., the fourth foam), 3042 (e.g., the third foam), and 3043 (e.g., the fifth foam) cannot all be omitted.

[0169] The specific structure of the power supply unit 303 is as follows: Figure 15 As shown. Exemplarily, the power supply unit 303 includes: a power supply structure 3031, a PCB board 3032, and power supply points 3033. The power supply structure 3031 employs a shaped bracket for distributed power supply and is connected to the motherboard via a cable. Exemplarily, the shaped bracket can be a plastic structure used to fix a metal sheet, which is attached to the shaped bracket to form a shape as shown. Figure 15 Center-feed structure 3031. Engineers can adjust the shape of the metal sheet according to the pre-calculated values ​​of the antenna's inductance and capacitance to ensure that the resonant frequency of the resonant cavity antenna meets a preset frequency value (e.g., a resonant frequency of 2.45 GHz). Using a shaped distributed feed structure can reduce the number of components in the resonant cavity antenna. It is understood that this feed structure can also be other structures; this example does not limit the structure of feed structure 3031.

[0170] In one embodiment, an inductor and a capacitor can also be provided on the PCB board 3032 of the feed unit 303. By adjusting the inductor and capacitor, the resonant frequency of the resonant cavity antenna can be made to satisfy a preset frequency value. In this example, the feed unit 303 forms a distributed feed structure through the shape of the metal structure 3031 to complete the adjustment of the antenna's resonant frequency, saving components and wiring in the antenna. Furthermore, in this example, the resonant cavity antenna is used in conjunction with the metal frame, and is less affected by the environment or the floor position in the tablet computer.

[0171] Figure 16 This is a side view of an exemplary tablet computer and its resonant cavity antenna. Reference numeral 20 indicates a metal plate within the tablet computer's metal back cover. Reference numeral 40 indicates a battery within the tablet computer. Reference numeral 50 indicates a battery support wall within the tablet computer, and reference numeral 60 indicates an LCD metal layer. Reference numeral 3031 indicates a power supply structure, reference numeral 3032 indicates a PCB board, and reference numeral 3033 indicates a power supply point. Foam 3045 is placed on a pillar formed by the metal plate 20, and foam 3043 is placed on the battery support wall. The LCD layer covers foam 3045 and foam 3043, and because foam 3045 and foam 3043 are conductive to the LCD metal layer, they conduct electricity to the LCD metal layer, thus forming a boundary condition.

[0172] This example will combine Figures 17 to 20 Explain the S-parameters and efficiency of the resonant cavity antenna with different numbers of foams.

[0173] Figure 17 A schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with five foam elements is shown as an example. S1,1 represents the resonant cavity antenna located as shown in the diagram. Figure 6 The resonance curve (i.e., the S-parameter curve) at position ②. Figure 17 The suffix Rad indicates the antenna's radiation efficiency. Figure 17 The designation Tot indicates the system efficiency of the antenna. Figure 17 The three curves in the middle are smooth with few protrusions.

[0174] Figure 18 A schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with four foam elements is shown as an example. S1,1 represents the resonant cavity antenna located as shown in the diagram. Figure 6 The resonance curve (i.e., the S-parameter curve) at position ②. Figure 18 The suffix Rad indicates the antenna's radiation efficiency. Figure 18 The symbol Tot indicates the system efficiency of the antenna. Figure 18 Foam 3041 or foam 3043 has been removed from the mid-cavity resonant antenna. Figure 18 It includes 5 spikes, which generate 5 clutter waves, reducing the antenna performance of the resonant cavity antenna.

[0175] Figure 19 This is a schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with default foam 3042, as exemplarily shown. S1,1 represents the resonant cavity antenna located as shown in the diagram. Figure 6 The resonance curve (i.e., the S-parameter curve) at position ②. Figure 19 The suffix Rad indicates the antenna's radiation efficiency. Figure 19 The symbol Tot indicates the system efficiency of the antenna. Figure 19 Foam 3042 was removed from the mid-cavity resonant antenna. Figure 19 The inclusion of seven spikes generates seven clutter lines, reducing the antenna performance of the resonant cavity antenna. Clutter is typically generated at locations with high electric fields; placing foam 3042 at a position relatively parallel to these high electric field points can significantly reduce clutter generation.

[0176] Figure 20 A schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna comprising five foam elements is shown as an example. S1,1 represents the resonant cavity antenna located as shown in the diagram. Figure 6 The resonance curve (i.e., the S-parameter curve) at position ②. Figure 20 The suffix Rad indicates the antenna's radiation efficiency. Figure 20 The symbol Tot indicates the system efficiency of the antenna. Figure 20 The line connecting foams 3043 and 3045 is not perpendicular to the line connecting 3041 and 3043, thus creating a non-strict boundary condition for foams 3043 and 3045. Alternatively, the line connecting foams 3041 and 3044 could also not be perpendicular to the line connecting 3041 and 3043, resulting in a non-strict boundary condition for foams 3041 and 3044. Figure 20 The resonant cavity antenna generated four clutter waves, which reduced the antenna performance of the resonant cavity antenna.

[0177] In this example, foams 3044 and 3045 are crucial for constructing the fundamental mode radiation aperture and are indispensable. The longer the foam and the more adequate the grounding, the less clutter impact. Foam 3042, which has a higher electric field, determines the excitation amplitude of the parallel plate clutter; therefore, foam with a higher electric field is essential. Even if foams 3041 or 3043 are omitted from the resonant cavity antenna, clutter will still exist. This example uses... Figure 14 The structure of the five foam elements results in a relatively smooth curve and low clutter amplitude in the resonant cavity antenna.

[0178] Figure 21(1) shows a schematic diagram of the electric field distribution in a standard resonant cavity. Figure 21(1) shows the cross-section formed by a and b in the resonant cavity antenna, in which a signal of half a wavelength is generated in the standard resonant cavity. Figure 21(2) shows the cross-section formed by a and b in the resonant cavity antenna in this example, in which a signal of 1 / 4 wavelength is generated in the resonant cavity. In Figure 21(2), the first slot of the resonant cavity antenna is opened on the front side formed by a and L (i.e., the side close to the display screen), and the resonant cavity antenna in Figure 21(2) effectively produces a magnetic current along the b-axis direction, thus having an omnidirectional radiation pattern perpendicular to the b-axis direction, and also having the characteristics of low-profile vertical polarization.

[0179] In this example, the resonant cavity antenna adopts the front-facing slotted method shown in Figure 21 (2). In the application, the black edge of the filler between the metal frame of the tablet computer and the display screen can be used as the first slot, so there is no need to make a separate slot for the metal frame, which will not damage the industrial design of the tablet computer.

[0180] Figure 22 This is a two-dimensional radiation pattern of the resonant cavity antenna shown in this example. Figure 22 The resonant cavity antenna operates at TE 0.5,0,1 The 2D radiation pattern indicates that the vertical polarization component Theta and Tot polarization curves almost overlap, meaning the dominant polarization is vertical, and the horizontal polarization component is very weak. In the embodiments of this application, the resonant cavity antenna and other frame antennas can form polarization orthogonal, achieving dual-polarization equalization of the antenna in the tablet computer and improving the tablet computer's signal reception capability.

[0181] In this example, the resonant cavity antenna uses TE 0.5,0,1 This resonant cavity antenna is relatively independent, and its standing wave ratio and radiation efficiency are less affected by location and environment. It can be positioned away from where the user holds the tablet or near the keyboard's magnetic area. The antenna is vertically polarized, while other antennas in the tablet (such as Wi-Fi and Bluetooth antennas) are horizontally polarized. This creates a multiple-in multiple-out (MIMO) orthogonal polarized antenna, overcoming the limitation of single antenna polarization in tablets and improving the tablet's ability to receive and transmit electromagnetic signals. In this application, the resonant cavity antenna can also be used independently as a Bluetooth or Wi-Fi antenna.

[0182] In one embodiment, the dimensions of the resonant cavity can be w=3mm, a=15.5mm, b=6.5mm, and L=80mm. The resonant cavity antenna uses a TE antenna. 0.5,0,1The mode is in operation. The position of the first gap can be adjusted, such as using the positions (1) to (4) in Figure 23.

[0183] Figure 23(1) is an exemplary schematic diagram of the cross-section of the antenna cavity 301 when the high axis (i.e., b) near the side of the first slot is reduced by d1. As shown in Figure 23(1), d1 is used to indicate the reduction in height of the high axis (i.e., b) near the first slot. In this example, d1 can be 0.5 mm. Figure 24(1) is an exemplary schematic diagram of the coverage area of ​​the resonant cavity antenna in a three-dimensional radiation pattern when b1 is reduced by 0.5 mm. As shown in Figure 24(1), the electric field direction of the resonant cavity antenna covers the tablet. The rectangle in Figure 24(1) is the tablet. Figure 23(2) is an exemplary schematic diagram of the cross-section of the resonant cavity antenna when the high axis (i.e., b) near the side of the first slot is reduced by d2. As shown in Figure 23(2), d2 is used to indicate the reduction in height of the high axis (i.e., b) near the side of the first slot. In this example, d2 can be 1 mm. Figure 24(2) is an exemplary schematic diagram of the coverage area of ​​the resonant cavity antenna in a three-dimensional radiation pattern when b is reduced by 1 mm. As shown in Figure 24(2), the electric field direction of the resonant cavity antenna covers the tablet computer. The rectangle in Figure 24(2) represents the tablet computer.

[0184] Figure 23(3) is an exemplary schematic diagram of the mid-end face of the resonant cavity antenna when the high axis (i.e., b) of the side near the first slot is reduced by d3. As shown in Figure 23(3), d3 is used to indicate the reduction in height of the high axis (i.e., b) of the side near the first slot. In this example, d3 can be 2 mm. Figure 24(3) is an exemplary schematic diagram of the coverage area of ​​the resonant cavity antenna in a three-dimensional radiation pattern when b is reduced by 2 mm. As shown in Figure 24(3), the electric field direction of the resonant cavity antenna covers the tablet. The rectangle in Figure 24(3) represents the tablet.

[0185] Figure 23(4) is an exemplary schematic diagram showing the first slot being opened in the middle of the B1 plane. As shown in Figure 23(4), when the slot is in the middle of the B1 plane, it is equivalent to a magnetic flow along the high axis direction, with an omnidirectional radiation pattern perpendicular to the high axis direction, and at the same time has the characteristic of low profile vertical polarization. As shown in Figure 24(4), the electric field direction of this resonant cavity antenna covers the tablet optimally. The rectangle in Figure 24(1) is the tablet.

[0186] Figure 25 This is a schematic diagram of the structure of a resonant cavity antenna as an example. Figure 25 coordinate system and Figure 3 The coordinate system is consistent with that in the previous section, and will not be elaborated further here. The first gap 302 is located in the middle of the B1 surface, and the direction of the first gap 301 extends along the Z-axis. Using... Figure 25The resonant cavity antenna shown is integrated with the overall structure of the device as follows: Figure 14 As shown. This first gap can be set on the metal frame.

[0187] Figure 26 This example illustrates the two-dimensional (i.e., 2D) radiation pattern of the resonant cavity antenna when the first slot is located in the middle of plane B1. The resonant cavity antenna operates at TE... 0.5,0,1 The 2D radiation pattern indicates that the vertical polarization component Theta almost overlaps with the Tot polarization curve. Figure 26 (The Theta curve is not visible in the image), meaning that the main polarization is vertical and the horizontal polarization component is very weak. Therefore, the resonant cavity antenna and the frame antenna form polarization orthogonal, which can achieve dual polarization equalization.

[0188] In this example, referring to Figures 23 and 24, the directivity of the resonant cavity antenna is optimal when the first slot is located in the middle of the side facade. As the slot moves towards the front of the screen, the external electric field distribution of the resonant cavity antenna becomes asymmetrical, and the proportion of the field intensity on the front gradually increases. However, due to the edge effect, a considerable number of electric field lines still bypass the edge, exciting the electric field on the metal back of the tablet computer through the induced potential difference, thus achieving field coverage of the metal back of the tablet computer. Simultaneously, compared to a resonant cavity antenna with a front slot, reducing the height of the side facade improves the directivity of the resonant cavity antenna. When the height of the side facade of the resonant cavity antenna is reduced by 2mm, the directivity can be reduced to 5dBi. The directivity range of the first slot between the top of the side or the front position is 4.4~6.4dBi. Maintaining the width of the first slot unchanged, slightly reducing the height of the side facade near the first slot can reduce the directivity.

[0189] In one embodiment, the resonant cavity antenna can also employ TE. 0.5,0,0.5 Working in a mode. For example... Figure 9 The diagram shows the effect of the length on the antenna performance of the resonant cavity antenna. Figure 1 It can be seen that when the length L of the resonant cavity antenna is 40mm, the resonant cavity is smaller than TE. 0.5,0,1 The mode covers 2.45GHz. Figure 27 This is a three-dimensional schematic diagram of a resonant cavity antenna as an example. Figure 27 As shown, the axis extending along the Z-direction of this resonant cavity antenna is taken as the major axis, denoted as L'. The resonant cavity antenna along... Figure 27 The axis extending in the X direction is taken as the width axis and denoted as a. In this resonant cavity antenna, along... Figure 4The axis extending in the Y direction is designated as the height axis, denoted as b. The first slot 302 is disposed on the C1 surface, its width denoted as w, and its direction extends along the Z-axis. The diagonal lines filling the image indicate the dielectric in the resonant cavity antenna. Optionally, in this example, the dimensions of the resonant cavity antenna are illustrated using w=3mm, a=15.5mm, b=6.5mm, and L'=45mm as examples. Figure 27 As shown, one cross-section of this resonant cavity antenna is an open end face (i.e., Figure 27 (A1 side in the middle).

[0190] In this example, the resonant cavity antenna uses TE. 0.5,0,0.5 In this mode, the major axis L' is shortened. Using TE... 0.5,0,0.5 The volume of the resonant cavity antenna in this mode is much smaller than that of the one using TE. 0.5,0,1 The reduced size of the resonant cavity antenna lowers the difficulty of deployment and increases its flexibility. The antenna includes an open end face, saving material.

[0191] Figure 28 The resonant cavity antenna shown as an example uses TE 0.5,0,0.5 A schematic diagram showing the locations of different power supply units during the mode. Figure 28 This is a top view of the tablet computer. Figure 28 Reference numeral 30 indicates the resonant cavity antenna, reference numeral 303 indicates the feed section, and reference numeral 101 is the metal frame. Reference numeral ① is located near surface A1, with a value of 0 in the Y direction and a value in the X direction that is close to the first gap and greater than w. Reference numeral ② has a value of 1 / 2L' in the Z direction, a value of 0 in the Y direction, and a value in the X direction that is close to the first gap and greater than w. Reference numeral ③ has a value in the Z direction that is greater than 1 / 2L' and less than or equal to L', a value of 0 in the Y direction, and a value in the X direction that is close to the first gap and greater than w.

[0192] This example incorporates the three-dimensional orientation patterns of the power supply unit 303 at three different locations shown in Figure 29.

[0193] Figure 29(1) shows the three-dimensional radiation pattern of the resonant cavity antenna when the feed unit 303 is at position ①. As shown in Figure 29(1), the directivity of the resonant cavity antenna is 6.61 dBi. The resonant cavity antenna in Figure 29(1) uses a TE... 0.5,0,0.5 The mode covers 2.45GHz.

[0194] Figure 29(2) shows the three-dimensional radiation pattern of the resonant cavity antenna when the feed unit 303 is at position ②. As shown in Figure 29(2), the directivity of the resonant cavity antenna is 6.40 dBi. The resonant cavity antenna in Figure 29(2) uses a TE...0.5,0,0.5 The mode covers 2.45GHz.

[0195] Figure 29(3) shows the three-dimensional radiation pattern of the resonant cavity antenna when the feed unit 303 is at position ③. As shown in Figure 29(3), the directivity of the resonant cavity antenna is 6.30 dBi. The resonant cavity antenna in Figure 29(2) uses TE 0.5,0,0.5 The mode covers 2.45GHz.

[0196] As shown in Figures 29(1) to 29(3) in this example, when the feed section is close to the open-circuit boundary (i.e., the A1 plane), the directivity of the fundamental mode tends to increase, but the increment is only 0.3 dBi. Therefore, it can be seen that the position of the feed section has little impact on the external radiation field distribution of the resonant cavity antenna in this example.

[0197] Should Figure 30 This is a schematic diagram illustrating the radiation efficiency of the resonant cavity antenna at different positions of the feed section 303, as shown by example. Figure 30 The curve labeled ① is the radiation efficiency curve of the resonant cavity antenna when it is located at position ① in Figure 29. Figure 30 The curve labeled ② is the radiation efficiency curve of the resonant cavity antenna when it is located at position ② in Figure 29. Figure 30 The radiation efficiency curve for the resonant cavity antenna at position ③ in Figure 29 is shown in Figure 29. The peak value of the radiation efficiency curve at position ① is the value of triangle 2. The peak value of the radiation efficiency curve at position ② is the value of triangle 3. The peak value of the radiation efficiency curve at position ③ is the value of triangle 1. This radiation efficiency diagram shows that when the feed section 303 is close to the open-circuit boundary, both bandwidth and radiation efficiency are improved.

[0198] In this example, since the fundamental mode electric field point is more fully excited by the capacitive feed, the feed section 303 is closer to the open circuit boundary, which improves both bandwidth and radiation efficiency.

[0199] In this example, the dimensions of the resonant cavity antenna can be w=3mm, a=15.5mm, b=6.5mm, and L'=45mm. The constructed resonant cavity antenna is deployed within the cavity formed by the metal back cover, metal frame, and display screen of the tablet computer. Optionally, to save space and material for the resonant cavity antenna deployment, the embodiments of this application employ... Figure 31 The resonant cavity antenna structure shown is shown.

[0200] Figure 31 This is a top view illustrating a tablet computer and a resonant cavity antenna. The tablet computer is placed parallel to a horizontal tabletop, and its dimensions are 276 (f-axis) mm × 187 (e-axis) mm. Figure 31In the diagram, reference numeral 90 indicates the motherboard in the tablet computer. Reference numeral 50 indicates the battery retainer in the tablet computer. Reference numeral 20 indicates the metal plate in the tablet computer. Reference numeral 30 indicates the resonant cavity antenna. The resonant cavity antenna includes: a feed section 303, foam (such as...) Figure 31 Medium foam 3046~foam 3049) and the first gap ( Figure 31 (The gap and display screen are not shown). The antenna cavity 301 of this resonant cavity antenna consists of foam, a metal plate, and an LCD metal layer covering the foam. Figure 31 The LCD metal layer is not shown in the image.

[0201] Foams 3046 to 3049 are conductive foams used to construct the boundary conditions of the resonant cavity antenna. The lengths of foams 3046 to 3048 form the major axis L' of the resonant cavity antenna. The combination of foam 3048 (as in the third foam) and foam 3049 (as in the first foam) forms the short-circuit boundary of the closed section in the resonant cavity antenna (i.e., the closed section formed by the combination of the wide axis a and the high axis b). In this example, the wide axis a formed by foams 3048 and 3049 is perpendicular to the major axis L' formed by foams 3046 (as in the second foam) and 3048, forming a strict boundary condition. The position of foam 3047 (as in the fourth foam) is parallel to the position of the feed section 303. Foam 3049 is a key foam for constructing the fundamental mode radiation aperture and is indispensable. Since the feed section 303 is deployed at a location with a large electric field, foam 3046, used to eliminate clutter generated by the feed section, is indispensable. Optionally, foams 3046, 3047, and 3048 cannot all be missing. The specific structure of the power supply section 303 can be as follows: Figure 15 As shown, further details will not be elaborated here.

[0202] This example will combine Figures 32a to 32f This section explains the S-parameters and efficiency of the resonant cavity antenna when different numbers of foam are used.

[0203] Figure 32a The diagram illustrates the S-parameters and efficiency of a resonant cavity antenna with four foam elements, as shown as an example. S1,1 is the resonance curve (i.e., the S-parameter curve) of this resonant cavity antenna. Figure 32a The suffix Rad indicates the antenna's radiation efficiency. Figure 32a The symbol Tot indicates the system efficiency of the antenna. Figure 32a The three curves in the middle are smooth with few spikes and no clutter within the band.

[0204] Figure 32b This is a schematic diagram illustrating the S-parameters and radiation efficiency of a resonant cavity antenna with default foam 3046, as shown as an example. S1,1 is the resonance curve (i.e., the S-parameter curve) of this resonant cavity antenna. Figure 32bThe suffix Rad indicates the antenna's radiation efficiency. Figure 32b The symbol Tot indicates the system efficiency of the antenna. Figure 32b Foam 3046 was removed from the mid-cavity resonant antenna. Figure 32b The radiation efficiency curve and system efficiency curve show that the resonant frequency of the resonant cavity antenna shifts, and there is a lot of clutter. Since foam 3046 is used to eliminate clutter generated by large electric field points, removing foam 3046 results in more clutter. Therefore, foam 3046 cannot be omitted.

[0205] Figure 32c This is a schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with default foam 3047, as shown as an example. S1,1 is the resonance curve (i.e., the S-parameter curve) of this resonant cavity antenna. Figure 32c The suffix Rad indicates the antenna's radiation efficiency. Figure 32c The symbol Tot indicates the system efficiency of the antenna. Figure 32c Foam 3047 was removed from the mid-cavity resonant antenna. Figure 32c Five clutter waves were generated, which reduced the antenna performance of the resonant cavity antenna.

[0206] Figure 32d This is a schematic diagram illustrating the S-parameters and efficiency of a resonant cavity antenna with default foam 3048, as shown as an example. S1,1 is the resonance curve (i.e., the S-parameter curve) of this resonant cavity antenna. Figure 32d The suffix Rad indicates the antenna's radiation efficiency. Figure 32d The numeral Tot is used to indicate the system efficiency of the antenna. For example, the... Figure 32c This generates a clutter wave, which reduces the antenna performance of the resonant cavity antenna.

[0207] Figure 32e The diagram illustrates the S-parameters and efficiency of a resonant cavity antenna with default foam 3046 and foam 3048 as an example. S1,1 is the resonance curve (i.e., the S-parameter curve) of this resonant cavity antenna. Figure 32e The suffix Rad indicates the antenna's radiation efficiency. Figure 32e The symbol Tot indicates the system efficiency of the antenna. According to... Figure 32e The resonant frequency of the resonant cavity antenna shifted, and there was a lot of clutter.

[0208] Figure 32f The diagram illustrates the S-parameters and efficiency of another resonant cavity antenna, including four foam elements, as shown as an example. S1,1 is the resonance curve (i.e., the S-parameter curve) of this resonant cavity antenna. Figure 32f The suffix Rad indicates the antenna's radiation efficiency. Figure 32fThe designation Tot indicates the system efficiency of the antenna. The line connecting foams 3048 and 3049 is not perpendicular to the line connecting 3046 and 3048, resulting in a non-strict boundary condition between foams 3048 and 3049. Figure 32f The resonant cavity antenna generated three clutter waves, which reduced the antenna performance of the resonant cavity antenna.

[0209] In this example, the longer the foam length and the more adequate the grounding, the less affected the resonant cavity antenna is by clutter. The foam 3046 at the point of high electric field determines the excitation amplitude of the parallel plate clutter; the foam 3046 at this point of high electric field is indispensable. The resonant cavity antenna uses TE... 0.5,0,0.5 This design reduces the volume of the resonant cavity antenna by nearly half, facilitating flexible deployment. However, because the resonant cavity antenna requires meeting boundary conditions to excite the fundamental mode at a specified frequency, clutter still exists even when the antenna includes three foam elements. When using... Figure 31 The structure shown has four foam particles. The resonant cavity antenna produces a relatively smooth curve with very small clutter amplitude.

[0210] Figure 33 This is a two-dimensional radiation pattern of the resonant cavity antenna shown in this example. Figure 33 The resonant cavity antenna operates at TE 0.5,0,0.5 The 2D radiation pattern indicates that the vertical polarization component Theta and Tot polarization curves almost overlap, meaning the dominant polarization is vertical, and the horizontal polarization component is very weak. In the embodiments of this application, the resonant cavity antenna and the frame antenna can form polarization orthogonal, enabling dual-polarization equalization of the antenna in a tablet computer.

[0211] In this example, the resonant cavity antenna uses TE 0.5,0,0.5 In mode, power line distribution and TE 0.5,0,1 The mode remains consistent. The boundary conditions in the L' direction change, the fundamental mode changes from 1 / 2 wavelength to 1 / 4 wavelength, the main polarization remains vertical polarization, and the volume ratio adopts TE. 0.5,0,1 The mode was reduced by 50%.

[0212] Figure 34 This is a schematic diagram illustrating an exemplary location for a resonant cavity antenna deployment. Figure 34 The reference numeral ① is used to indicate the deployment location of the resonant cavity antenna in this application. Figure 34 101 is used to indicate the metal frame in the tablet computer, which measures 276 (f-axis) mm × 187 (e-axis) mm. Figure 34 Reference numerals ② and ③ are used to indicate the deployment locations of other antennas in the tablet computer, such as Bluetooth antennas, Wi-Fi antennas, etc.

[0213] Figure 35 The resonant cavity antenna shown as an example operates at TE.0.5,0,1 This diagram illustrates the isolation between the antenna and other antennas in mode. In this example, the first slot in the resonant cavity antenna is located on the front side (e.g., ...). Figure 4 (The first gap shown). Figure 35 S3,1 is used to indicate the isolation curve between the resonant cavity antenna and the antenna at position ③. Figure 35 S2,1 is used to indicate the isolation curve between the resonant cavity antenna and the antenna at position ②. From the values ​​of triangle 1 in both curves S3,1 and S2,1, it can be seen that the isolation between the resonant cavity antenna and the antenna at position ② is 37 dB, and the isolation between the resonant cavity antenna and the antenna at position ③ is also 37 dB.

[0214] Figure 36 Another resonant cavity antenna shown as an example operates at TE 0.5,0,1 This diagram illustrates the isolation between the antenna and other antennas in mode. In this example, the first slot in the resonant cavity antenna is located on the side facade (e.g., Figure 26 (The first gap shown). Figure 35 S3,1 is used to indicate the isolation curve between the resonant cavity antenna and the antenna at position ③. Figure 35 S2,1 is used to indicate the isolation curve between the resonant cavity antenna and the antenna at position ②. From the values ​​of triangle 1 in curves S3,1 and S2,1, it can be seen that the isolation between the resonant cavity antenna and the antenna at position ② is 65 dB (accurate to the nearest whole number), and the isolation between the resonant cavity antenna and the antenna at position ③ is also 65 dB (accurate to the nearest whole number).

[0215] Figure 37 This is a schematic diagram illustrating an exemplary location for a resonant cavity antenna deployment. Figure 37 The reference numeral ① is used to indicate the deployment location of the resonant cavity antenna in this application. Figure 37 101 is used to indicate the metal frame in the tablet computer, which measures 276 (f-axis) mm × 187 (e-axis) mm. Figure 37 Reference numerals ② and ③ are used to indicate the deployment locations of other antennas in the tablet computer, such as Bluetooth antennas, Wi-Fi antennas, etc.

[0216] Figure 38 The resonant cavity antenna shown as an example operates at TE. 0.5,0,0.5 This diagram illustrates the isolation between the antenna and other antennas in mode. In this example, the first slot in the resonant cavity antenna is located on the front side (e.g., ...). Figure 4 (The first gap shown). Figure 38 S3,1 is used to indicate the resonant cavity antenna and Figure 37 The isolation curve between antennas at position ③ (marked in the middle) Figure 38S2,1 is used to indicate the resonant cavity antenna and Figure 37 The isolation curves between the antennas at position ② are shown. Based on the values ​​of triangle 1 in curves S3,1 and S2,1, the isolation between this resonant cavity antenna and the antenna at position ② is 50 dB, and the isolation between this resonant cavity antenna and the antenna at position ③ is 19 dB.

[0217] In this example, the resonant cavity antenna is placed far away from other antennas, resulting in high isolation and reducing mutual interference between different antennas.

[0218] Any content in the various embodiments of this application, as well as any content in the same embodiment, can be freely combined. Any combination of the above content is within the scope of this application.

[0219] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A resonant cavity antenna, used in electronic devices, characterized in that, include: Antenna cavity, first slot, and feed section; The antenna cavity is filled with an insulating medium. At least one side of the first surface of the antenna cavity is parallel to the length of the display screen of the electronic device. At least one side of the second surface of the antenna cavity is parallel to the length of the display screen. The plane containing the first surface and the plane containing the second surface intersect. The plane containing the first surface is parallel to the plane containing the display screen. The plane containing the display screen is the plane formed by the major axis and the minor axis of the electronic device. The first gap is formed on the second surface, and at least a portion of the first gap extends along the length of the display screen; The feed section is located inside the antenna cavity, and the feed section does not contact any surface of the antenna cavity; The feed section is located at the point of maximum electric field in the antenna cavity, which is the location in the resonant cavity antenna where the maximum electric field is generated. If the mode of the resonant cavity antenna is TE 0.5,0,1 The position of the electric field point projected onto the first surface is as follows: its value in the first direction is 1 / 2 of the length of the third side, and it is located near the first gap in the second direction. The first direction is the extension direction of the long axis of the electronic device, the second direction is the extension direction of the short axis of the electronic device, and the third side is the side of the first surface that is parallel to the length of the display screen.

2. The resonant cavity antenna according to claim 1, characterized in that, The second surface is divided into a first part and a second part by the first gap. The first side of the first part is perpendicular to the side of the second surface that is parallel to the length of the display screen, and the second side of the second part is perpendicular to the side of the second surface that is parallel to the length of the display screen. The length of the first side is equal to the length of the second side.

3. The resonant cavity antenna according to claim 1, characterized in that, The antenna cavity includes a third surface and a fourth surface. The plane containing the third surface intersects with the plane containing the first surface, and the plane containing the third surface intersects with the plane containing the second surface. The plane containing the fourth surface is parallel to the plane containing the third surface. If the mode of the resonant cavity antenna is TE 0.5,0,0.5 The third surface is a closed conductive wall, and the fourth surface is not covered by a conductive wall, forming an open surface; The position of the large electric field point projected onto the first surface is: close to the four surfaces in the first direction, and the value in the second direction is greater than the width of the first gap and close to the first gap. The first direction is the extension direction of the long axis of the electronic device, and the second direction is the extension direction of the short axis of the electronic device.

4. The resonant cavity antenna according to claim 1, characterized in that, The power supply unit includes a power supply structure and a power supply point; The power supply structure includes a plastic shaping bracket and a metal sheet attached to the shaping bracket. The shaping bracket is fixed to the PCB board at the power supply point.

5. The resonant cavity antenna according to claim 4, characterized in that, The metal sheet is attached to the shaping bracket in a preset shape so that the feeding structure generates a preset resistance and inductance to meet the operating frequency of the resonant cavity antenna.

6. The resonant cavity antenna according to any one of claims 1 to 5, characterized in that, The plane containing the first surface of the antenna cavity is parallel to the plane containing the display screen, and the plane containing the display screen is the plane formed by the major axis of the electronic device and the minor axis of the electronic device. The metal frame of the electronic device has a second gap; The second gap and the first gap at least partially coincide on the orthographic projection of the plane in which the metal frame is located, and the plane in which the metal frame is located is perpendicular to the plane in which the display screen is located.

7. The resonant cavity antenna according to any one of claims 1, 2, 4 or 5, characterized in that, The antenna cavity comprises, from bottom to top, the following: a metal plate of the electronic device, three conductive foams, and a liquid crystal display (LCD) metal layer covering the three foams, with the display screen covering the LCD metal layer. The first foam and the second foam are located on the metal plate; The battery rib baffle of the electronic device is located on the metal plate, and the third foam is located on the battery rib baffle, with the third foam being close to the power supply part. The line connecting the first foam and the second foam is parallel to the battery rib baffle.

8. The resonant cavity antenna according to claim 7, characterized in that, The antenna cavity also includes a fourth foam, which is located on the battery rib baffle wall and is aligned with the second foam or the first foam.

9. The resonant cavity antenna according to claim 8, characterized in that, The antenna cavity also includes a fifth foam; The fifth foam is located on the battery rib retaining wall; If the fourth foam is aligned with the second foam, then the fifth foam is aligned with the first foam; If the fourth foam is aligned with the first foam, then the fifth foam is aligned with the second foam.

10. The resonant cavity antenna according to any one of claims 1, 2, 3 to 5, characterized in that, The antenna cavity comprises, from bottom to top, the following: a metal plate of the electronic device, at least two conductive foams, and a liquid crystal display (LCD) metal layer covering the two foams, with the display screen covered on the LCD metal layer; The first foam is located on the metal plate; The battery rib baffle of the electronic device is located on the metal plate, the second foam is located on the battery rib baffle, and the second foam is located near the power supply part; the angle between the line connecting the first foam and the second foam and the battery rib baffle is greater than 0 degrees and less than or equal to 45 degrees.

11. The resonant cavity antenna according to claim 10, characterized in that, The antenna cavity also includes a third foam, which is located on the battery rib retaining wall.

12. The resonant cavity antenna according to claim 11, characterized in that, The antenna cavity also includes a fourth foam, which is located on the battery rib retaining wall; If the third foam is aligned with the first foam, then the fourth foam is located between the second foam and the third foam; If the third foam is located between the first foam and the second foam, then the fourth foam is aligned with the first foam.

13. The resonant cavity antenna according to claim 1, characterized in that, The antenna cavity includes a third surface and a fourth surface. The plane containing the third surface intersects with the plane containing the first surface, and the plane containing the third surface intersects with the plane containing the second surface. The plane containing the fourth surface is parallel to the plane containing the third surface. If the resonant frequency of the resonant cavity is 2.45 GHz, the operating mode is TE. 0.5,0,1 Then the third and fourth surfaces are closed conductive walls.

14. The resonant cavity antenna according to claim 13, characterized in that, The plane containing the fifth surface of the antenna cavity is parallel to the plane containing the display screen, the first surface is parallel to the plane containing the display screen, and the plane containing the display screen is the plane formed by the major axis and the minor axis of the electronic device. The height of the antenna cavity is the distance between the plane containing the first surface and the plane containing the fifth surface; The third side is the side of the first surface that is parallel to the length of the display screen; The resonant cavity antenna operates at TE. 0.5,0,1 In this mode, the length of the third side ranges from [0.5λ - 0.5λ × 20%, 0.5λ + 0.5λ × 20%], the plane containing the first surface intersects the plane containing the third surface at the fourth side, the length of the fourth side ranges from [0.25λ - 0.25λ × 10%, 0.25λ + 0.25λ × 10%], and the height is less than 0.25λ, where λ is used to indicate the wavelength at which the resonant cavity antenna operates.

15. The resonant cavity antenna according to claim 14, characterized in that, The third side of the antenna cavity is 80mm, the fourth side is 15.5mm, and the height is 6.5mm.

16. The resonant cavity antenna according to claim 3, characterized in that, The plane containing the third surface of the antenna cavity intersects the plane containing the first surface, and the plane containing the third surface also intersects the plane containing the second surface; the plane containing the fourth surface of the antenna cavity is parallel to and intersects the plane containing the third surface. If the resonant frequency of the resonant cavity is 2.45 GHz, the operating mode is TE. 0.5,0,0.5 Then the third surface is a closed conductive wall, and the fourth surface is an uncovered conductive wall, forming an open surface.

17. The resonant cavity antenna according to claim 16, characterized in that, The plane containing the fifth surface of the antenna cavity is parallel to the plane containing the display screen, the first surface is parallel to the plane containing the display screen, and the plane containing the display screen is the plane formed by the major axis and the minor axis of the electronic device. The height of the antenna cavity is the distance between the plane containing the first surface and the plane containing the fifth surface; the third side is the side of the first surface that is parallel to the length of the display screen. The length of the third side ranges from [0.25λ - 0.25λ × 20%, 0.25λ + 0.25λ × 20%], the plane containing the first side intersects the plane containing the third side at the fourth side, the length of the fourth side ranges from [0.25λ - 0.25λ × 10%, 0.25λ + 0.25λ × 10%], the height is less than 0.25λ, where λ is used to indicate the wavelength at which the resonant cavity antenna operates.

18. The resonant cavity antenna according to claim 17, characterized in that, The third side of the antenna cavity is 45mm, the fourth side is 15.5mm, and the height is 6.5mm.

19. The resonant cavity antenna according to claim 1, characterized in that, The plane containing the metal frame of the electronic device is perpendicular to the plane containing the display screen; The plane containing the second surface coincides with the plane containing the metal frame.

20. An electronic device, characterized in that, include: At least one frame antenna and a resonant cavity antenna as described in any one of claims 1 to 19; The frame antenna is located at a first corner or a second corner of the electronic device, wherein the first corner is adjacent to the second corner; If the resonant cavity antenna operates at TE 0.5,0,1 In this mode, the resonant cavity antenna is located midway between the third and fourth corners, and the line connecting the third and fourth corners is parallel to the line connecting the first and second corners. If the resonant cavity antenna operates at TE 0.5,0,0.5 In this mode, the resonant cavity antenna is located at the third or fourth corner.

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