Antenna structure and wearable device

Abstract

The embodiment of the invention provides an antenna structure and a wearable device, and aims to reduce loss during electromagnetic wave transmission. According to the wearable device provided by the invention, an antenna structure comprises a first branch knot, a second branch knot and a third branch knot; the first branch knot and the second branch knot are located on the same side of the third branch knot and arranged in parallel. The length of the first branch knot is 70%-130% of the length of the second branch knot, electromagnetic waves generated by the first branch knot and electromagnetic waves generated by the second branch knot counteract each other, and when the wearable device is worn on the head of a user, the included angle between the electric field polarization direction of the electromagnetic waves generated by the third branch knot and the horizontal plane is 30-80 degrees. An included angle (shown as an angle A in figure 8) between the maximum radiation direction of the electromagnetic wave generated by the third branch knot and the horizontal plane is 30-80 degrees; and in the radiation direction, the loss during electromagnetic wave transmission is minimum, so that the connection stability between the wearable equipment and the communication equipment is improved.

Description

Technical Field

[0001] This application relates to the field of antenna technology, specifically to an antenna structure and a wearable device. Background Technology

[0002] The antenna structure can communicate with mobile terminals, such as mobile phones and tablets, via Bluetooth, thereby enabling the mobile terminal to perform functions such as playing music and making calls. When a user carries a communication device and wears the antenna structure, the human body absorbs electromagnetic waves in the signal propagation path, increasing the loss of electromagnetic waves during transmission and causing communication interruptions between the antenna structure and the mobile terminal. Summary of the Invention

[0003] This application provides an antenna structure and a wearable device, which aim to improve the connection stability between the wearable device and the communication device.

[0004] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0005] On one hand, embodiments of this application provide a wearable device for wearing on a user's head. The wearable device includes a housing and an antenna structure, with the antenna structure located inside the housing. The antenna structure includes a radiator, a first feed point, and a ground plane. The radiator is used to generate a first resonance and includes a first stub, a second stub, and a third stub. The first and second stubs are both located on the same side of the third stub and are arranged in parallel. One end of the third stub is coupled to the first end of the first stub, and the other end of the third stub is coupled to the second end of the second stub. The angle between the length direction of the third stub and the length direction of the first stub is 75° to 105°. When the wearable device is worn on the user's head, the angle between the length direction of the first stub and the horizontal plane is 30° to 80°. The length of the first stub is 70% to 130% of the length of the second stub. The first feed point is located on the first stub. The ground plane is spaced apart from the radiator.

[0006] The wearable device provided in this application embodiment has a third branch with one end coupled to the first end of the first branch and the other end coupled to the second end of the second branch. The first and second branches are located on the same side of the third branch and are arranged in parallel. The length of the first branch is 70% to 130% of the length of the second branch, and the angle between the length direction of the third branch and the length direction of the first branch is 75° to 105°. When the wearable device is worn on the user's head, the angle between the length direction of the first branch and the horizontal plane is 30° to 80°. The first power supply point is located on the first branch. By feeding the radiator through the first feed point, the radiator generates a first resonance. The electromagnetic waves generated by the first stub cancel each other out with the electromagnetic waves generated by the second stub. The electric field polarization direction of the electromagnetic waves generated by the third stub makes an angle of 10° to 60° with the horizontal plane, so that the maximum radiation direction of the electromagnetic waves generated by the third stub makes an angle of 30° to 80° with the horizontal plane. In this radiation direction, the electromagnetic waves can bypass the human body and be transmitted to the communication device located below the wearable device in the form of crawling waves. This avoids the electromagnetic waves passing through the human body, reduces the absorption of electromagnetic waves by the human body on the transmission path, and thus reduces the loss of electromagnetic waves during transmission. This improves the connection stability between the wearable device and the communication device.

[0007] In some embodiments, the length of the first stub is equal to the length of the second stub. The currents in the first and second stubs are in opposite directions.

[0008] By setting it up as described above, the electromagnetic waves generated by the first branch cancel each other out with the electromagnetic waves generated by the second branch, thereby reducing the influence of the electromagnetic waves generated by the first or second branch on the electromagnetic waves generated by the third branch.

[0009] In some embodiments, at the resonant frequency of the first resonance, the current-strong point of the radiator is located on the third stub, which has a midpoint along its length, and the distance between the current-strong point and the midpoint is less than or equal to one-quarter of the length of the third stub. This is to ensure that the electric field polarization direction of the electromagnetic wave generated by the third stub is as perpendicular as possible to the length direction of the first stub.

[0010] In the above embodiment, when the current strong point coincides with the midpoint, the electric field polarization direction of the electromagnetic wave generated by the third branch is completely perpendicular to the length direction of the first branch.

[0011] In some embodiments, the resonant frequency of the first resonator includes 2.4 GHz, and the total length of the first stub, the second stub, and the third stub is between 30 mm and 55 mm.

[0012] In some embodiments, the length of the third stub is greater than 4.5 mm, and the distance between the first and second stubs is 0.2 mm to 5 mm. This is to ensure that the electric field polarization direction of the electromagnetic wave generated by the third stub is more perpendicular to the length direction of the first stub.

[0013] In some embodiments, the antenna structure further includes a coaxial line, a second feed point is provided on the second stub, the first feed point is used to couple the inner conductor of the coaxial line, and the second feed point is used to couple the outer conductor of the coaxial line.

[0014] In some embodiments, the antenna structure further includes a grounding point disposed on the second stub, wherein the length from the first feed point to the first end is 70% to 130% of the length from the grounding point to the second end.

[0015] The above configuration allows the electromagnetic waves generated on the first branch to cancel each other out with those generated on the second branch, reducing the influence of the electromagnetic waves generated on the third branch; and the electric field polarization direction of the electromagnetic waves generated on the third branch is perpendicular to the length direction of the first branch.

[0016] In some embodiments, the antenna structure further includes a switch, one end of which is coupled to a ground point and the other end of which is configured to be grounded; when the switch is in the off state, the radiator is used to generate a first resonance; when the switch is in the on state, the radiator is used to generate a second resonance; the resonant frequency of the second resonance is greater than the resonant frequency of the first resonance.

[0017] With the above settings, when the switch is in the off state, the total electrical length of the radiator remains unchanged, and the radiator is still used to generate the first resonance. When the switch is in the on state, the total electrical length of the radiator decreases, and the radiator generates the second resonance.

[0018] In some embodiments, the length from the first feed point to the first end is equal to the length from the ground point to the second end.

[0019] By setting it up as described above, the electromagnetic waves generated by the first branch cancel each other out with the electromagnetic waves generated by the second branch, thereby reducing the influence of the electromagnetic waves generated by the first or second branch on the electromagnetic waves generated by the third branch.

[0020] In some embodiments, the resonant frequency of the second resonance includes 5.8 GHz, and the total length of the first feed point to the first end, the ground point to the second end, and the third stub is between 25 mm and 45 mm.

[0021] In some embodiments, the housing includes an ear flap and an ear stem, with the ear flap disposed at one end of the ear stem; an antenna structure is disposed inside the ear stem, with the length direction of the first stalk parallel to the length direction of the ear stem.

[0022] With the above configuration, the antenna structure is positioned within the earpiece, with the length direction of the first stalk parallel to the length direction of the earpiece. This ensures that the electric field polarization direction of the electromagnetic wave generated by the third stalk forms an angle of 10° to 60° with the horizontal plane, and that the maximum radiation direction of the electromagnetic wave generated by the third stalk forms an angle of 30° to 80° with the horizontal plane. In this radiation direction, the electromagnetic wave can bypass the human body and be transmitted to the communication device located below the wearable device in the form of a crawling wave. This avoids the electromagnetic wave passing through the human body, reduces the absorption of the electromagnetic wave by the human body along the transmission path, and thus reduces the loss during electromagnetic wave transmission. This improves the connection stability between the wearable device and the communication device.

[0023] In some embodiments, the ear sac is located at the top of the ear stem, the third branch is coupled to the end of the first branch near the ear sac, and the third branch is coupled to the end of the second branch near the ear sac.

[0024] With the above configuration, the opening formed by the radiator faces the end of the ear stem away from the ear sac, which can enhance the radiation of electromagnetic waves generated by the third stalk along the length of the first stalk.

[0025] On the other hand, this application embodiment also provides an antenna structure for use in the aforementioned wearable device, which is worn on a user's head. The antenna structure includes a radiator, a first feed point, and a ground plane. The radiator is used to generate a first resonance and includes a first stub, a second stub, and a third stub. The first and second stubs are both located on the same side of the third stub and are arranged in parallel. One end of the third stub is coupled to the first end of the first stub, and the other end of the third stub is coupled to the second end of the second stub. The angle between the length direction of the third stub and the length direction of the first stub is 75° to 105°. When the wearable device is worn on the user's head, the angle between the length direction of the first stub and the horizontal plane is 30° to 80°. The length of the first stub is 70% to 130% of the length of the second stub. The first feed point is located on the first stub. The ground plane is spaced apart from the radiator.

[0026] The antenna structure provided in this application embodiment has one end of the third stub coupled to the first end of the first stub, and the other end of the third stub coupled to the second end of the second stub. The first stub and the second stub are located on the same side of the third stub and are arranged in parallel. The length of the first stub is 70% to 130% of the length of the second stub, and the angle between the length direction of the third stub and the length direction of the first stub is 75° to 105°. When the wearable device is worn on the user's head, the angle between the length direction of the first stub and the horizontal plane is 30° to 80°. The first feed point is located on the first stub. By feeding the radiator through the first feed point, the radiator generates a first resonance. The electromagnetic waves generated by the first stub cancel each other out with the electromagnetic waves generated by the second stub. The electric field polarization direction of the electromagnetic waves generated by the third stub makes an angle of 10° to 60° with the horizontal plane, making the maximum radiation direction of the electromagnetic waves generated by the third stub make an angle of 30° to 80° with the horizontal plane. In this radiation direction, the electromagnetic waves can bypass the human body and be transmitted to the communication device located below the antenna structure in the form of crawling waves. This avoids the electromagnetic waves passing through the human body, reduces the absorption of electromagnetic waves by the human body on the transmission path, and thus reduces the loss during electromagnetic wave transmission. This improves the connection stability between the wearable device and the communication device.

[0027] In some embodiments, the length of the first stub is equal to the length of the second stub. The currents in the first and second stubs are in opposite directions.

[0028] By setting it up as described above, the electromagnetic waves generated by the first branch cancel each other out with the electromagnetic waves generated by the second branch, thereby reducing the influence of the electromagnetic waves generated by the first or second branch on the electromagnetic waves generated by the third branch.

[0029] In some embodiments, at the resonant frequency of the first resonance, the current-strong point of the radiator is located on the third stub, which has a midpoint along its length, and the distance between the current-strong point and the midpoint is less than or equal to one-quarter of the length of the third stub. This is to ensure that the electric field polarization direction of the electromagnetic wave generated by the third stub is as perpendicular as possible to the length direction of the first stub.

[0030] In the above embodiment, when the current strong point coincides with the midpoint, the electric field polarization direction of the electromagnetic wave generated by the third branch is completely perpendicular to the length direction of the first branch.

[0031] In some embodiments, the resonant frequency of the first resonator includes 2.4 GHz, and the total length of the first stub, the second stub, and the third stub is between 30 mm and 55 mm.

[0032] In some embodiments, the length of the third stub is greater than 4.5 mm, and the distance between the first and second stubs is 0.2 mm to 5 mm. This allows the electric field polarization direction of the electromagnetic wave generated by the third stub to be more perpendicular to the length direction of the first stub.

[0033] In some embodiments, the antenna structure further includes a coaxial line, a second feed point is provided on the second stub, the first feed point is used to couple the inner conductor of the coaxial line, and the second feed point is used to couple the outer conductor of the coaxial line.

[0034] In some embodiments, the antenna structure further includes a grounding point disposed on the second stub, wherein the length from the first feed point to the first end is 70% to 130% of the length from the grounding point to the second end.

[0035] The above configuration allows the electromagnetic waves generated on the first branch to cancel each other out with those generated on the second branch, reducing the influence of the electromagnetic waves generated on the third branch; and the electric field polarization direction of the electromagnetic waves generated on the third branch is perpendicular to the length direction of the first branch.

[0036] In some embodiments, the antenna structure further includes a switch, one end of which is coupled to a ground point and the other end of which is configured to be grounded; when the switch is in the off state, the radiator is used to generate a first resonance; when the switch is in the on state, the radiator is used to generate a second resonance; the resonant frequency of the second resonance is greater than the resonant frequency of the first resonance.

[0037] With the above settings, when the switch is in the off state, the total electrical length of the radiator remains unchanged, and the radiator is still used to generate the first resonance. When the switch is in the on state, the total electrical length of the radiator decreases, and the radiator generates the second resonance.

[0038] In some embodiments, the length from the first feed point to the first end is equal to the length from the ground point to the second end.

[0039] By setting it up as described above, the electromagnetic waves generated by the first branch cancel each other out with the electromagnetic waves generated by the second branch, thereby reducing the influence of the electromagnetic waves generated by the first or second branch on the electromagnetic waves generated by the third branch.

[0040] In some embodiments, the resonant frequency of the second resonance includes 5.8 GHz, and the total length of the first feed point to the first end, the ground point to the second end, and the third stub is between 25 mm and 45 mm. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in some embodiments of this application will be briefly described below. Obviously, the drawings described below are only drawings of some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not intended to limit the actual size of the product, the actual flow of the method, the actual timing of the signals, etc. involved in the embodiments of this application.

[0042] Figure 1 This is a schematic diagram of the structure of the wearable device in the embodiments of this application. Figure 1 ;

[0043] Figure 2 This is a schematic diagram of the structure of the wearable device in the embodiments of this application. Figure 2 ;

[0044] Figure 3 This is a schematic diagram of the antenna structure in the embodiments of this application. Figure 1 ;

[0045] Figure 4 This is a schematic diagram of the antenna structure in the embodiments of this application. Figure 2 ;

[0046] Figure 5 The parameter curves of the antenna structure in the embodiments of this application are shown. Figure 1 ;

[0047] Figure 6 The current distribution of the antenna structure in the embodiments of this application. Figure 1 ;

[0048] Figure 7 This is a schematic diagram of a user wearing a wearable device in an embodiment of this application;

[0049] Figure 8 This is a schematic diagram of the wearable device in the wearing state in the embodiments of this application;

[0050] Figure 9 This is a schematic diagram of the antenna structure in the embodiments of this application. Figure 3 ;

[0051] Figure 10 This is a schematic diagram of the antenna structure in the embodiments of this application. Figure 4 ;

[0052] Figure 11 This is a schematic diagram of the antenna structure in the embodiments of this application. Figure 5 ;

[0053] Figure 12 This is a schematic diagram of the antenna structure in the embodiments of this application. Figure 6 ;

[0054] Figure 13 This is a schematic diagram of the antenna structure in the embodiments of this application. Figure 7 ;

[0055] Figure 14 This is a schematic diagram of the switch connection of the antenna structure in an embodiment of this application;

[0056] Figure 15 The parameter curves of the antenna structure in the embodiments of this application are shown. Figure 2 ;

[0057] Figure 16 The current distribution of the antenna structure in the embodiments of this application. Figure 2 ;

[0058] Figure 17 The parameter curves of the antenna structure in the embodiments of this application are shown. Figure 3 ;

[0059] Figure 18 The current distribution of the antenna structure in the embodiments of this application. Figure 3 .

[0060] Explanation of reference numerals in the attached drawings: 300, wearable device; 100, antenna structure; 10, radiator; 11, first stub; 110, first end; 111, first part; 112, second part; 12, second stub; 120, second end; 13, third stub; 20, first feed point; 30, PCB; 40, second feed point; 50, grounding point; 60, switch; 70, feed line; 200, housing; 210, earpiece; 220, ear stem; 310, communication equipment. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, 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.

[0062] Hereinafter, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature.

[0063] Furthermore, in the embodiments of this application, directional terms such as "up," "down," "left," "right," "horizontal," and "vertical" are defined relative to the orientation of the components shown in the accompanying drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the orientation of the components in the accompanying drawings.

[0064] The following explains the terminology that may appear in the embodiments of this application.

[0065] Communication connection: This can refer to the transmission of electrical signals, such as wireless communication connections and / or wired communication connections. Wireless communication connections do not require a physical medium and are not considered connections that limit the structure of a product.

[0066] Coupling can be understood as direct coupling and / or indirect coupling. "Coupled connection" can be understood as a direct coupling connection and / or indirect coupling connection. Direct coupling can also be called "electrical connection," which can be understood as physical contact and electrical conduction between components; it can also be understood as the form of connection between different components in a circuit structure through physical lines that can transmit electrical signals, such as copper foil or wires on a printed circuit board (PCB). "Indirect coupling" can be understood as electrical conduction between two conductors through a gap / non-contact method. In one embodiment, indirect coupling can also be called capacitive coupling, for example, signal transmission is achieved by forming an equivalent capacitance through coupling between the gaps between two conductive parts.

[0067] A radiator, or antenna stub, is a device in an antenna used to receive / transmit electromagnetic wave radiation. In some cases, the term "antenna" is narrowly defined as a radiator, which converts guided wave energy from the transmitter into radio waves, or converts radio waves into guided wave energy, for radiating and receiving radio waves. The modulated high-frequency current energy (or guided wave energy) generated by the transmitter is transmitted to the transmitting radiator via a feed line, where it is converted into electromagnetic wave energy of a specific polarization and radiated in the desired direction. The receiving radiator converts electromagnetic wave energy of a specific polarization from a specific direction in space back into modulated high-frequency current energy, which is then transmitted to the receiver input via a feed line.

[0068] Radiators (or antenna stubs) may include conductors with specific shapes and sizes, such as wires or sheets, and this application does not limit the specific shape. In one embodiment, a wire radiator may be simply referred to as a wire antenna. In one embodiment, a wire radiator may be implemented by a conductive frame, and may also be referred to as a frame antenna. In one embodiment, a wire radiator may be implemented by a support conductor, and may also be referred to as a support antenna. In one embodiment, the wire diameter (e.g., including thickness and width) of the wire radiator, or the radiator of the wire antenna, is much smaller than the wavelength (e.g., the wavelength of the medium) (e.g., less than 1 / 16 of the wavelength), and the length may be comparable to the wavelength (e.g., the wavelength of the medium) (e.g., a length of approximately 1 / 8 of the wavelength, or 1 / 8 to 1 / 4, or 1 / 4 to 1 / 2, or longer). The main forms of wire antennas include dipole antennas, half-wave dipole antennas, monopole antennas, loop antennas, and inverted F antennas (also known as IFAs). For example, in a dipole antenna, each dipole antenna typically includes two radiating stubs, each fed from the feed end of the radiating stub by a feed section. For example, an inverted-F antenna (IFA) can be considered as a monopole antenna with an added ground path. An IFA antenna has one feed point and one ground point, and is called an inverted-F antenna because its side view is inverted-F shaped. In one embodiment, the sheet radiator may include a microstrip antenna or a patch antenna, such as a planar inverted-F antenna (also known as a PIFA). In one embodiment, the sheet radiator may be implemented using a planar conductor (e.g., a conductive sheet or conductive coating). In one embodiment, the sheet radiator may include a conductive sheet, such as a copper sheet. In one embodiment, the sheet radiator may include a conductive coating, such as silver paste. The shape of the sheet radiator includes circular, rectangular, and annular shapes, and this application does not limit the specific shape. The structure of a microstrip antenna generally consists of a dielectric substrate, a radiator, and a ground plane, wherein the dielectric substrate is disposed between the radiator and the ground plane.

[0069] Radiators (or antenna stubs) may also include slots or gaps formed on a conductor, for example, closed or semi-closed slots or gaps formed on a grounded conductor surface. In one embodiment, a slotted or slit radiator may be simply referred to as a slot antenna or a gap antenna. In one embodiment, the radial dimension (e.g., including width) of the slot or gap of the slot antenna / gap antenna is much smaller than the wavelength (e.g., the dielectric wavelength) (e.g., less than 1 / 16 of the wavelength), while the length dimension may be comparable to the wavelength (e.g., the dielectric wavelength) (e.g., a length of approximately 1 / 8 of the wavelength, or 1 / 8 to 1 / 4, or 1 / 4 to 1 / 2, or longer). In one embodiment, a radiator with a closed slot or gap may be simply referred to as a closed slot antenna. In one embodiment, a radiator with a semi-closed slot or gap (e.g., an opening added to a closed slot or gap) may be simply referred to as an open slot antenna. In some embodiments, the gap shape is elongated. In some embodiments, the length of the gap is approximately half a wavelength (e.g., the dielectric wavelength). In some embodiments, the length of the gap is approximately an integer multiple of a wavelength (e.g., one dielectric wavelength). In some embodiments, the slot can be fed by transmission lines connected across one or both sides, thereby exciting a radio frequency electromagnetic field on the slot and radiating electromagnetic waves into space. In one embodiment, the radiator of the slot antenna or gap antenna can be implemented by a conductive frame grounded at both ends, also known as a frame antenna; in this embodiment, the slot antenna or gap antenna can be viewed as including a linear radiator, the linear radiator being spaced apart from the ground and grounded at both ends, thereby forming a closed or semi-closed slot or gap. In one embodiment, the radiator of the slot antenna or gap antenna can be implemented by a support conductor grounded at both ends, also known as a support antenna.

[0070] A feed line, also called a transmission line, is the connection line between the antenna transceiver and the radiator. Transmission lines can transmit current waves or electromagnetic waves directly, depending on the frequency and type. The connection point on the radiator where the transmission line connects is usually called the feed point. Transmission lines include conductive transmission lines, coaxial transmission lines, waveguides, and microstrip lines. Depending on their implementation, transmission lines can be mounted on a support antenna or a glass antenna. Depending on the carrier, transmission lines can be made of LCP (Liquid Crystal Polymer), FPC (Flexible Printed Circuit), or PCB (Printed Circuit Board).

[0071] Ground / Plug: This can broadly refer to at least a portion of any grounding layer, ground plane, or grounding metal layer within an electronic device (such as a mobile phone), or at least a portion of any combination of the aforementioned grounding layers, ground planes, or grounding components. "Ground / Plug" can be used for grounding components within an electronic device. In one embodiment, "Ground / Plug" may include any one or more of the following: a grounding layer of a circuit board of an electronic device, a ground plane formed by the frame of the electronic device, a grounding metal layer formed by a thin metal film beneath the screen, a conductive grounding layer of a battery, and conductive or metallic components electrically connected to the aforementioned grounding layer / ground plane / metal layer. In one embodiment, the circuit board may be a printed circuit board (PCB), such as an 8-layer, 10-layer, or 12-14-layer board having 8, 10, 12, 13, or 14 layers of conductive material, or components separated and electrically insulated by dielectric or insulating layers such as glass fiber or polymers. In one embodiment, the circuit board includes a dielectric substrate, a grounding layer, and a trace layer, with the trace layer and grounding layer electrically connected via vias. In one embodiment, components such as display 120, touch screen, input buttons, transmitter, processor, memory, battery 140, charging circuit, system-on-chip (SoC) architecture, etc., may be mounted on or connected to the circuit board; or electrically connected to the trace layers and / or ground layers in the circuit board. For example, an RF source is disposed on a trace layer.

[0072] Any of the aforementioned grounding layers, ground planes, or grounding metal layers are made of conductive materials. In one embodiment, the conductive material may be any of the following: copper, aluminum, stainless steel, brass and their alloys, copper foil on an insulating substrate, aluminum foil on an insulating substrate, gold foil on an insulating substrate, silver-plated copper, silver-plated copper foil on an insulating substrate, silver foil on an insulating substrate and tin-plated copper, graphite-impregnated cloth, graphite-coated substrates, copper-plated substrates, brass-plated substrates, and aluminum-plated substrates. Those skilled in the art will understand that grounding layers / ground planes / grounding metal layers may also be made of other conductive materials.

[0073] Grounding: refers to coupling with the aforementioned ground / floor via a grounding structure and / or grounding circuit. In one embodiment, grounding can be achieved through physical grounding, such as through a structural component of the mid-frame to achieve physical grounding at a specific location on the frame (or, physical ground). In another embodiment, grounding can be achieved through device grounding, such as through devices like capacitors / inductors / resistors connected in series or parallel (or, device ground).

[0074] Resonant frequency: The resonant frequency is also called the resonance frequency. The resonant frequency can have a frequency range, that is, the frequency range in which resonance occurs. The resonant frequency can be a frequency range where the return loss characteristic is less than -6dB. The point of strongest resonance can be called the resonant point, and the frequency corresponding to the resonant point is the center frequency. The return loss characteristic of the center frequency can be less than -20dB. It should be understood that, unless otherwise specified, when the antenna / radiator in this application generates "first / second...resonance," the first resonance should be the fundamental mode resonance generated by the antenna / radiator, or in other words, the lowest frequency resonance generated by the antenna / radiator. It should be understood that the antenna / radiator can generate one or more antenna modes according to a specific design, and each antenna mode can correspond to a fundamental mode resonance.

[0075] Electrical length: Electrical length can be expressed as the ratio of physical length (i.e., mechanical length or geometric length) multiplied by the time it takes for an electrical or electromagnetic signal to travel in a medium to the time required for that signal to travel a distance in free space equal to the physical length of the medium. Electrical length can be expressed by the following formula:

[0076]

[0077] Where L is the physical length, a is the transmission time of the electrical or electromagnetic signal in the medium, and b is the transmission time in free space.

[0078] Alternatively, electrical length can also refer to the ratio of physical length (i.e., mechanical length or geometric length) to the wavelength of the transmitted electromagnetic wave, and electrical length can satisfy the following formula:

[0079]

[0080] Where L is the physical length and λ is the wavelength of the electromagnetic wave.

[0081] In some embodiments of this application, the physical length of the radiator can be understood as within ±20%, ±10%, or ±5% of the electrical length of the radiator.

[0082] In the embodiments of this application, the wavelength in a certain wavelength mode of the antenna (such as a half-wavelength mode) can refer to the wavelength of the signal radiated by the antenna. For example, the half-wavelength mode of a suspended metal antenna can generate resonance in the 1.575 GHz band, where the wavelength in the half-wavelength mode refers to the wavelength of the signal radiated by the antenna in the 1.575 GHz band.

[0083] Wavelength: or operating wavelength, can be the wavelength corresponding to the center frequency of the resonant frequency or the center frequency of the operating frequency band supported by the antenna. For example, assuming the center frequency of the B1 uplink band (resonant frequency from 1920MHz to 1980MHz) is 1955MHz, then the operating wavelength can be the wavelength calculated using this frequency. Not limited to the center frequency, "operating wavelength" can also refer to the wavelength corresponding to the non-center frequency of the resonant frequency or operating frequency band.

[0084] It should be understood that the wavelength of a radiation signal in air can be calculated as follows: (air wavelength, or vacuum wavelength) = speed of light / frequency, where the frequency is the frequency of the radiation signal (MHz), and the speed of light can be taken as 3 × 10⁸ m / s. The wavelength of a radiation signal in a medium can be calculated as follows:

[0085]

[0086] Where ε is the relative permittivity of the medium. The wavelength in the embodiments of this application typically refers to the medium wavelength, which can be the medium wavelength corresponding to the center frequency of the resonant frequency, or the medium wavelength corresponding to the center frequency of the operating frequency band supported by the antenna. For example, assuming the center frequency of the B1 uplink band (resonant frequency of 1920MHz to 1980MHz) is 1955MHz, then the wavelength can be the medium wavelength calculated using this frequency. Not limited to the center frequency, the "medium wavelength" can also refer to the medium wavelength corresponding to the non-center frequency of the resonant frequency or operating frequency band. For ease of understanding, the medium wavelength mentioned in the embodiments of this application can be simply calculated using the relative permittivity of the medium filling one or more sides of the radiator.

[0087] End / Point: The term "end / point" in the context of the antenna radiator's first end / second end / feed end / ground end / feed point / ground point / connection point should not be narrowly interpreted as necessarily being a point or end physically disconnected from other radiators. It can also be considered as a point or segment on a continuous radiator. In one embodiment, "end / point" can include a connection / coupling region on the antenna radiator that is coupled to other conductive structures. For example, a feed end / feed point can be a coupling region on the antenna radiator that is coupled to a feed structure (e.g., a region facing a part of the feed structure). Similarly, a ground end / ground point can be a connection / coupling region on the antenna radiator that is coupled to a ground structure.

[0088] The terms "middle" or "middle position" used in the embodiments of this application refer to specific ranges or distances. For example, the middle (position) of a conductor can refer to a section of the conductor including its midpoint, or a section of the conductor including its midpoint that is one-eighth of a wavelength. The wavelength can be the wavelength corresponding to the antenna's operating frequency band, the wavelength corresponding to the center frequency of the operating frequency band, or the wavelength corresponding to the resonant point. As another example, the middle (position) of a conductor can refer to a section of the conductor located less than a predetermined threshold (e.g., 1 mm, 2 mm, or 2.5 mm) from the midpoint. The middle position of a slot or the middle position of one side of a slot refers to the middle position of one side of the slot.

[0089] The terms collinearity, coaxiality, coplanarity, symmetry (e.g., axial symmetry, or central symmetry), parallelism, perpendicularity, and similarity (e.g., same length, same width, etc.) mentioned in the embodiments of this application are all relative to the current technological level, and not absolute and strict mathematical definitions. There may be a deviation of less than a predetermined threshold (e.g., 1 mm, 0.5 mm, or 0.1 mm) between the edges of two collinear radiating stubs or two antenna elements in the line width direction. There may be a deviation of less than a predetermined threshold between the edges of two coplanar radiating stubs or two antenna elements in the direction perpendicular to their coplanar plane. There may be a deviation of a predetermined angle between two parallel or perpendicular antenna elements. In one embodiment, the predetermined threshold may be less than or equal to a threshold of 1 mm, for example, the predetermined threshold may be 0.5 mm or 0.1 mm. In one embodiment, the predetermined angle may be an angle within the range of ±10°, for example, the predetermined angle deviation is ±5°.

[0090] The current in the same direction / opposite direction mentioned in the embodiments of this application should be understood as the main current on the same side of the conductor being in the same direction / opposite direction. For example, when a current distributed in the same direction is excited on a conductor that is bent or looped (e.g., the current path is also bent or looped), it should be understood that, for example, the main current excited on the conductors on both sides of a looped conductor (e.g., on the conductors on both sides of a gap) is opposite in direction, but it still falls under the definition of current distributed in the same direction in this application. In one embodiment, current in the same direction on a conductor can mean that the current on the conductor has no reversal point. In one embodiment, current in opposite direction on a conductor can mean that the current on the conductor has at least one reversal point. In one embodiment, current in the same direction on two conductors can mean that the currents on both conductors have no reversal point and flow in the same direction. In one embodiment, current in opposite direction on two conductors can mean that the currents on both conductors have no reversal point and flow in opposite directions. Current in the same direction / opposite direction on multiple conductors can be understood accordingly.

[0091] Antenna system efficiency (total efficiency): refers to the ratio of input power to output power at the antenna port.

[0092] Antenna radiation efficiency refers to the ratio of the power radiated into space by an antenna (i.e., the power effectively converted into electromagnetic waves) to the active power input to the antenna. Active power input to the antenna = antenna input power - loss power; loss power mainly includes return loss power and ohmic loss power of metals and / or dielectric loss power. Radiation efficiency is a measure of an antenna's radiation capability; metal loss and dielectric loss are both factors affecting radiation efficiency.

[0093] Those skilled in the art will understand that efficiency is generally expressed as a percentage, and there is a corresponding conversion relationship between it and dB. The closer the efficiency is to 0dB, the better the efficiency of the antenna.

[0094] dB: This stands for decibel, a logarithmic concept with base 10. Decibels are used to evaluate the proportional relationship between two physical quantities; they themselves have no physical dimensions. For every 10-fold increase in the ratio between two quantities, their difference can be expressed as 10 decibels. For example: A = 100, B = 10, C = 5, D = 1, then A / D = 20 dB; B / D = 10 dB; C / D = 7 dB; B / C = 3 dB. In other words, a 10-decibel difference between two quantities is a 10-fold difference, a 20-decibel difference is a 100-fold difference, and so on. A 3-decibel difference is a 2-fold difference between the two quantities.

[0095] dBi: Usually mentioned together with dBd. dBi and dBd are units of power gain, both relative values, but with different reference points. The reference point for dBi is an omnidirectional antenna; the reference point for dBd is a dipole. Generally, dBi and dBd are considered to represent the same gain, but the value expressed in dBi is 2.15 dBi larger than that expressed in dBd. For example, for an antenna with a gain of 16 dBd, its gain converted to dBi is 18.15 dBi, generally ignoring the decimal places, hence 18 dBi.

[0096] Antenna return loss: This can be understood as the ratio of the signal power reflected back to the antenna port after passing through the antenna circuit to the transmit power at the antenna port. The smaller the reflected signal, the larger the signal radiated into space through the antenna, and the higher the antenna's radiation efficiency. Conversely, the larger the reflected signal, the smaller the signal radiated into space through the antenna, and the lower the antenna's radiation efficiency.

[0097] Antenna return loss can be represented by the S11 parameter, which is one of the S-parameters. S11 represents the reflection coefficient, and this parameter characterizes the antenna's transmission efficiency.

[0098] In one embodiment, the S11 diagram can be understood as a schematic diagram representing the resonance generated by the antenna. In one embodiment, the resonance shown in the S11 diagram within the range of -6dB can be understood as the resonant frequency / frequency range / operating frequency band generated by the antenna. The S11 parameter is usually negative. The smaller the S11 parameter, the smaller the antenna return loss, the less energy reflected back by the antenna itself, which means more energy actually enters the antenna, and the higher the system efficiency of the antenna. The larger the S11 parameter, the greater the antenna return loss, and the lower the system efficiency of the antenna.

[0099] It should be noted that an S11 value of -4dB can be used as a standard. When the S11 value of an antenna is less than -4dB, the antenna can be considered to be working normally. It should be understood that, in engineering practice, an S11 value of -6dB can also be used as a standard. When the S11 value of an antenna is less than -6dB, the antenna's transmission efficiency can be considered to be good.

[0100] The technical solutions provided in this application are applicable to wearable devices employing one or more of the following communication technologies: Bluetooth (BT), Wi-Fi, Global System for Mobile Communications (GSM), Wideband Code Division Multiple Access (WCDMA), Long Term Evolution (LTE), 5G, and other future communication technologies. The wearable devices in this application are worn on a user's head and may include True Wireless Stereo (TWS) headphones, smart helmets, smart glasses, and Augmented Reality (AR) devices. TWS headphones may include ear-hook headphones, in-ear headphones, and over-ear headphones; AR devices may include AR headsets and AR glasses. The wearable devices can be used to communicate with communication devices, which may include mobile phones, tablets, and computers.

[0101] Please refer to Figure 1 and Figure 2This application provides an antenna structure 100, which can be applied to a wearable device 300 to transmit and receive signals. For example, the wearable device 300 may include a housing 200 and the antenna structure 100 described above. The housing 200 forms a mounting cavity, and the antenna structure 100 can be disposed within the housing 200, thereby fixing and sealing the antenna structure 100.

[0102] Please refer to Figure 3 The antenna structure 100 in this application embodiment may include a radiator 10, which is a conductor, such as stainless steel, copper, aluminum and other metals. Of course, the material of the radiator 10 may also include other non-metallic conductive materials. This application does not limit the material of the radiator 10, as long as the radiator 10 is conductive.

[0103] The shape of the radiator 10 is not limited in this application embodiment. For example, the radiator 10 can be a regular shape such as a plate, column, or strip. The following description will take the plate shape of the radiator 10 as an example. Of course, the radiator 10 can also be other irregular shapes. It is understood that the plate shape in this application embodiment can be a sheet with a thickness that is less than its width and length.

[0104] The radiator 10 may include a first branch 11, a second branch 12, and a third branch 13, which may be located in the same plane or in different planes. In the implementation where the first branch 11, the second branch 12, and the third branch 13 are located in the same plane, the first branch 11 and the second branch 12 are arranged in parallel, that is, the length directions of the first branch 11 and the second branch 12 are the same; while the length direction of the third branch 13 is different from the length direction of the first branch 11. The first branch 11 and the second branch 12 are both located on the same side of the third branch 13, and the first branch 11 and the third branch 13 may intersect, as may the second branch 12 and the third branch 13.

[0105] In the above implementation, the first branch 11 has a first end 110 coupled to the third branch 13, the second branch 12 has a second end 120 coupled to the third branch 13, the third branch 13 has a midpoint in its length direction, and the distance from the first end 110 to the midpoint of the third branch 13 is the same as the distance from the second end 120 to the midpoint of the third branch 13.

[0106] The antenna structure 100 may further include a first feed point 20, which may be located on the first stub 11. The first feed point 20 is used to receive the feed signal.

[0107] Reference Figure 3 and Figure 4The antenna structure 100 may also include a ground plane (not shown) spaced apart from the radiator 10. The wearable device 300 may also include a printed circuit board (PCB) disposed within the housing 200. The ground plane may be disposed on the PCB 30. The ground plane may also include other grounded and conductive plate-like structures.

[0108] Power is fed from the first feed point 20 to the radiator 10 via the feed line 70, causing the radiator 10 to generate a first resonance. In some embodiments, the total length of the first stub 11, the second stub 12, and the third stub 13 is between 30 mm and 55 mm, so that the total electrical length of the radiator 10 is approximately half the wavelength corresponding to 2.4 GHz, i.e., the resonant frequency of the first resonance can be in the 2.4 GHz band (e.g., 2.4 GHz - 2.4835 GHz). Figure 5 Parameter curves of the antenna structure Figure 1 L1 is the S11 curve, L2 is the antenna radiation efficiency, and L3 is the antenna system efficiency. The antenna system efficiency between points 1 and 2 on L3 is within -13dB to -15dB, indicating that the resonant frequency of the first resonance can be in the 2.4GHz band (e.g., 2.4GHz-2.4835GHz).

[0109] In the above embodiments, referring to Figure 3 The angle between the length direction of the third spur 13 and the length direction of the first spur 11 is 75° to 105°; the length of the first spur 11 is 70% to 130% of the length of the second spur 12, that is, the difference between the length of the first spur 11 and the length of the second spur 12 is less than 1 / 16 of the wavelength corresponding to 2.4 GHz. When feeding the radiator 10 through the first feed point 20, since the first spur 11 and the second spur 12 are arranged in parallel, then... Figure 6 As shown, the current directions on the first branch 11 and the second branch 12 are opposite (opposite current directions can be understood as the current direction at a certain moment being opposite to the current direction at a first point on the first branch 11 and the current direction at a second point on the second branch 12, with the first and second points corresponding to each other along the length of the third branch 13). This causes the electromagnetic waves generated by the first branch 11 to cancel each other out, reducing the influence of the electromagnetic waves generated by the first branch 11 or the second branch 12 on the electromagnetic waves generated by the third branch 13. The electric field polarization direction of the electromagnetic waves generated by the third branch 13 is the same as the length direction of the first branch 11. The current gradually increases from the end of the second branch 12 away from the third branch 13 towards the end closer to the third branch 13, with the current strength concentrated at the third branch 13. Subsequently, the current gradually decreases from the third branch 13 towards the end of the first branch 11 away from the third branch 13.

[0110] Please refer to Figure 7 and Figure 8When the wearable device 300 is worn on the user's head, the angle between the length direction of the first branch 11 and the horizontal plane (e.g., Figure 8 The angle between ∠A (as shown in the image) is 30° to 80°, which is the angle between the electric field polarization direction of the electromagnetic wave generated by the third branch 13 and the horizontal plane (as shown in the image). Figure 8 The angle ∠B (as shown in the figure) ranges from 10° to 60°.

[0111] In some implementations, the length direction of the third branch 13 can be perpendicular to the length direction of the first branch 11. In this case, when the wearable device 300 is worn on the user's head, the polarization direction of the electromagnetic wave generated by the third branch 13 can be perpendicular to the human body (i.e., the electromagnetic wave generated by the third branch 13 is transmitted along the signal transmission path 1). When the polarization direction of the electromagnetic wave is perpendicular to the human body, the influence of the human body on the electromagnetic wave is minimized, thereby reducing the absorption of the electromagnetic wave generated by the third branch 13 by the human body.

[0112] In the above embodiments, in order to improve the radiation efficiency of the antenna structure 100, the electrical length of the third stub 13 can be approximately 1 / 16 times the wavelength corresponding to 2.4 GHz, and its physical size is greater than 4.5 mm; the distance between the first stub 11 and the second stub 12 in the length direction of the third stub 13 is between 0.2 mm and 5 mm; the lengths of the first stub 11 and the second stub 12 are equal.

[0113] The wearable device 300 provided in this application embodiment has a third branch 13, one end of which is coupled to the first end 110 of the first branch 11, and the other end of which is coupled to the second end 120 of the second branch 12. The first branch 11 and the second branch 12 are located on the same side of the third branch 13 and are arranged in parallel. The length of the first branch 11 is 70% to 130% of the length of the second branch 12, and the angle between the length direction of the third branch 13 and the length direction of the first branch 11 is 75° to 105°. When the wearable device 300 is worn on the user's head, the angle between the length direction of the first branch 11 and the horizontal plane (e.g., ...) is... Figure 8 (As shown in the diagram) ∠A is 30° to 80°; the first feed point 20 is located on the first branch 11. Power is fed to the radiator 10 through the first feed point 20, causing the radiator 10 to generate a first resonance. The electromagnetic waves generated by the first branch 11 cancel each other out with the electromagnetic waves generated by the second branch 12. The angle between the electric field polarization direction of the electromagnetic waves generated by the third branch 13 and the horizontal plane (as shown in the diagram) is... Figure 8 The angle between ∠B (as shown in the image) and the horizontal plane is 10° to 60°, so that the angle between the maximum radiation direction of the electromagnetic wave generated by the third branch 13 and the horizontal plane is (as shown in the image). Figure 8(As shown in the diagram) ∠A is between 30° and 80°; in this radiation direction, electromagnetic waves can bypass the human body and transmit in the form of crawling waves to the communication device 310 located below the wearable device 300 (i.e., the electromagnetic waves generated by the third branch 13 are first transmitted through signal transmission path 1, and then through signal transmission path 2). This avoids the electromagnetic waves passing through the human body, reduces the absorption of electromagnetic waves by the human body along the transmission path, and thus reduces the loss during electromagnetic wave transmission; thereby improving the connection stability between the wearable device 300 and the communication device 310. (Refer to...) Figure 8 In some embodiments, at the resonant frequency of the first resonance, the current strong point of the radiator 10 is located on the third branch 13. In embodiments where the third branch 13 has a midpoint along its length, the distance between the current strong point and the midpoint is less than or equal to 1 / 4 of the length of the third branch 13. This ensures that the electric field polarization direction of the electromagnetic wave generated by the third branch 13 is as perpendicular as possible to the length direction of the first branch 11. Specifically, when the current strong point coincides with the midpoint, the electric field polarization direction of the electromagnetic wave generated by the third branch 13 is completely perpendicular to the length direction of the first branch 11. Furthermore, in embodiments where the length of the first branch 11 is the same as the length of the second branch 12, when the current strong point coincides with the midpoint, it can be ensured that the current directions on the first branch 11 and the second branch 12 are opposite, thereby causing the electromagnetic waves generated by the first branch 11 and the second branch 12 to cancel each other out, reducing the influence of the electromagnetic waves generated by the first branch 11 or the second branch 12 on the electromagnetic waves generated by the third branch 13.

[0114] In some embodiments, the first branch 11 and the second branch 12 can be regular plate-like structures (e.g., cuboids, cylinders, etc.). Please refer to... Figure 9 In other embodiments, the first branch 11 and the second branch 12 can also be irregular plate-like structures, as long as the total electrical length of the first branch 11, the second branch 12, and the third branch 13 is half the wavelength corresponding to 2.4 GHz. For example, the first branch 11 may include a first part 111 and a second part 112, both of which are regular plate-like structures. The first part 111 has a first end 110 coupled to the third branch 13, and the end of the first part 111 away from the first end 110 is coupled to the second part 112. The second part 112 is larger than the first part 111 in the width direction. The dimensions of the first part 111 and the second part 112 in the length and width directions can be set as needed to adjust the dimensions of the radiator 10 in the length and width directions of the first branch 11, facilitating the use of the space inside the wearable device 300 housing 200. It is understood that the second branch 12 may also include a third part and a fourth part (not shown in the figure), which will not be elaborated here.

[0115] Please refer to Figure 10 In some embodiments, the first branch 11, the second branch 12, and the third branch 13 can be a continuous structure, or slits can be made in individual branches 11, 12, and 13 to change the electrical length of the radiator 10. This allows for increasing or decreasing the physical size of the radiator 10 while maintaining its electrical length at half the wavelength corresponding to 2.4 GHz. Please refer to... Figure 11 Alternatively, gaps can be formed at the coupling points of the first branch 11 and the third branch 13, and at the coupling points of the second branch 12 and the third branch 13, which can change the electrical length of the radiator 10. Thus, while keeping the electrical length of the radiator 10 at 1 / 2 times the wavelength corresponding to 2.4 GHz, the physical size of the radiator 10 can be increased or decreased.

[0116] Please refer to Figure 12 In some embodiments, the antenna structure 100 further includes a feed line 70, which may be a coaxial line comprising an inner conductor and an outer conductor. In conjunction with embodiments where the antenna structure 100 includes a first feed point 20, the antenna structure 100 may also include a second feed point 40, which may be disposed on the second stub 12. The second feed point 40 is also used to receive the feed signal. The first feed point 20 is used to couple the inner conductor of the coaxial line, and the second feed point 40 is used to couple the outer conductor of the coaxial line.

[0117] In an embodiment where the antenna structure 100 includes both a first feed point 20 and a second feed point 40, the total electrical length of the radiator 10 remains unchanged, the radiator 10 is still used to generate the first resonance, the current strong point is located on the third stub 13, and the current directions on the first stub 11 and the second stub 12 are opposite.

[0118] Please refer to Figure 13 and Figure 14 In an embodiment where the antenna structure 100 includes a first feed point 20, the antenna structure 100 may further include a ground point 50 and a switch 60. The ground point 50 may be disposed on the second stub 12. One end of the switch 60 is coupled to the ground point 50, and the other end of the switch 60 is configured to be grounded. For example, in an embodiment where the antenna structure 100 includes a ground plane, the ground point 50 is coupled to the ground plane through the switch 60.

[0119] In the above embodiment, when switch 60 is in the off state, the total electrical length of radiator 10 remains unchanged, and radiator 10 is still used to generate the first resonance. When switch 60 is in the on state, the total electrical length of radiator 10 decreases, and radiator 10 generates a second resonance, the resonant frequency of the second resonance being greater than the resonant frequency of the first resonance.

[0120] Figure 15 Parameter curves of the antenna structure Figure 2L1 represents the S11 curve, L2 represents the antenna radiation efficiency, and L3 represents the antenna system efficiency. The antenna efficiency between points 1, 2, and 3 on L3 is within -13dB to -15dB, indicating that the resonant frequency of the first resonance can be in the 2.4GHz band (e.g., 2.4GHz-2.4835GHz). Figure 16 As shown, the current directions on the first branch 11 and the second branch 12 are opposite. When the switch 60 is in the open state, the current still gradually increases from the end of the second branch 12 away from the third branch 13 towards the end of the third branch 13. The current strength is concentrated at the third branch 13, and then gradually weakens from the third branch 13 towards the end of the first branch 11 away from the third branch 13.

[0121] In some embodiments, the total length of the first feed point 20 to the first end 110, the length of the ground point 50 to the second end 120, and the third branch 13 is between 25 mm and 45 mm, so that the total electrical length of the radiator 10 is approximately 1 times the wavelength corresponding to 5.8 GHz, that is, the resonant frequency of the second resonance can be in the 5.8 GHz band (e.g., 5.725 GHz - 5.85 GHz). Figure 17 Parameter curves of the antenna structure Figure 2 L1 is the S11 curve, L2 is the antenna radiation efficiency, and L3 is the antenna system efficiency. The antenna efficiency between points 1, 2, and 3 on L3 is within -4dB to -5dB, indicating that the resonant frequency of the first resonance can be in the 5.8GHz band (e.g., 5.725GHz-5.85GHz).

[0122] In the above embodiment, the length from the first feed point 20 to the first end 110 is 70% to 130% of the length from the ground point 50 to the second end 120, that is, the difference between the length from the first feed point 20 to the first end 110 and the length from the ground point 50 to the second end is less than 1 / 16 of the wavelength corresponding to 5.8 GHz. This causes the electromagnetic waves generated on the first stub 11 to cancel each other out with the electromagnetic waves generated on the second stub 12, reducing the influence of the electromagnetic waves generated by the first stub 11 or the second stub 12 on the electromagnetic waves generated by the third stub 13; and the electric field polarization direction of the electromagnetic waves generated by the third stub 13 is perpendicular to the length direction of the first stub 11.

[0123] In the above embodiment, in order to make the electric field polarization direction of the electromagnetic wave generated by the third branch 13 more perpendicular to the length direction of the first branch 11, the length from the first feed point 20 to the first end 110 is equal to the length from the ground point 50 to the second end 120. For example... Figure 18As shown, the current directions on the first branch 11 and the second branch 12 are opposite. When the switch 60 is in the conducting state, the current gradually weakens to zero from the grounding point 50 toward the third branch 13, forming a current zero point. Then it strengthens, and the current strength is concentrated at the third branch 13. Then it gradually weakens to zero from the third branch 13 toward the first feed point 20, forming a current zero point. Then it strengthens until it reaches the first feed point.

[0124] Similarly, the electromagnetic waves generated by the first branch 11 cancel each other out with the electromagnetic waves generated by the second branch 12, and the electric field polarization direction of the electromagnetic waves generated by the third branch 13 makes an angle (e.g., ...) with the horizontal plane. Figure 8 The angle between ∠B (as shown in the image) and the horizontal plane is 10° to 60°, so that the angle between the maximum radiation direction of the electromagnetic wave generated by the third branch 13 and the horizontal plane is (as shown in the image). Figure 8 The angle between ∠A and ∠A is 30° to 80°; in this radiation direction, electromagnetic waves can bypass the human body and be transmitted in the form of crawling waves to the communication device 310 located below the wearable device 300 (e.g., ...). Figure 7 As shown, the electromagnetic wave generated by the third branch 13 is transmitted first through signal transmission path 1 and then through signal transmission path 2. This avoids the electromagnetic wave passing through the human body, reduces the absorption of the electromagnetic wave by the human body on the transmission path, and thus reduces the loss during electromagnetic wave transmission, thereby improving the connection stability between the wearable device 300 or antenna structure 100 and the communication device 310.

[0125] Continue to refer to Figure 7 and Figure 8 In an embodiment where the wearable device 300 includes headphones, the housing 200 of the wearable device 300 includes an ear cup 210 and an ear stem 220, with the ear cup 210 disposed at one end of the ear stem 220. The ear cup 210 can be used to accommodate or embed within the user's auricle, and the ear stem 220 can be hooked onto the edge of the user's auricle, but not against the outer periphery of the user's auricle. When the wearable device 300 is in the wearing state, due to the structure of the human ear, the angle between the length direction of the ear stem 220 and the horizontal plane (e.g., ...) Figure 8 (As shown in the diagram) The angle is 30° to 80°. The antenna structure 100 is disposed within the lug 220, with the length direction of the first stalk 11 parallel to the length direction of the lug 220, so that the angle between the electric field polarization direction of the electromagnetic wave generated by the third stalk 13 and the horizontal plane (as shown in the diagram) is 30° to 80°. Figure 8 The angle between ∠B (as shown in the image) and the horizontal plane is 10° to 60°, so that the angle between the maximum radiation direction of the electromagnetic wave generated by the third branch 13 and the horizontal plane is (as shown in the image). Figure 8(As shown in the middle) ∠A is 30° to 80°; in this radiation direction, electromagnetic waves can bypass the human body and be transmitted to the communication device 310 located below the wearable device 300 in the form of crawling waves. This can prevent electromagnetic waves from passing through the human body, reduce the absorption of electromagnetic waves by the human body on the transmission path, and thus reduce the loss during electromagnetic wave transmission; thereby improving the connection stability between the wearable device 300 and the communication device 310.

[0126] In the above embodiment, the earbud 210 is located at the top of the ear stem 220, that is, when the wearable device 300 is worn, the earbud 210 is further away from the ground than the ear stem 220; the antenna structure 100 is located in the ear stem 220, the end of the first branch 11 near the earbud 210 is the first end 110 mentioned above, the end of the second branch 12 near the earbud 210 is the second end 120 mentioned above, and the third branch 13 is coupled to the first end 110 and the second end 120; the opening formed by the radiator 10 faces the end of the ear stem 220 away from the earbud 210, which can enhance the radiation of the electromagnetic waves generated by the third branch 13 along the length direction of the first branch 11.

[0127] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A wearable device for wearing on a user's head, characterized in that, The wearable device includes a housing and an antenna structure, the antenna structure being located within the housing; the antenna structure includes: A radiator for generating a first resonance, the radiator comprising a first stub, a second stub, and a third stub; the first stub and the second stub are both located on the same side of the third stub and are arranged in parallel; one end of the third stub is coupled to the first end of the first stub, and the other end of the third stub is coupled to the second end of the second stub; the angle between the length direction of the third stub and the length direction of the first stub is 75° to 105°; when the wearable device is worn on the user's head, the angle between the length direction of the first stub and the horizontal plane is 30° to 80°; the length of the first stub is 70% to 130% of the length of the second stub; The first feed point is located on the first branch; The floor is spaced apart from the radiator.

2. The wearable device according to claim 1, characterized in that, At the resonant frequency of the first resonance, the current strong point of the radiator is located on the third branch, the third branch has a midpoint in its length direction, and the distance between the current strong point and the midpoint is less than or equal to one-quarter of the length of the third branch.

3. The wearable device according to claim 1 or 2, characterized in that, The currents on the first branch and the second branch are in opposite directions.

4. The wearable device according to any one of claims 1-3, characterized in that, The resonant frequency of the first resonant includes 2.4 GHz, and the total length of the first stub, the second stub, and the third stub is between 30 mm and 55 mm.

5. The wearable device according to claim 4, characterized in that, The length of the third branch is greater than 4.5 mm, and the distance between the first branch and the second branch is 0.2 mm to 5 mm.

6. The wearable device according to any one of claims 1-5, characterized in that, The antenna structure also includes a coaxial line, and a second feed point is provided on the second branch. The first feed point is used to couple the inner conductor of the coaxial line, and the second feed point is used to couple the outer conductor of the coaxial line.

7. The wearable device according to any one of claims 1-5, characterized in that, The antenna structure also includes a grounding point, which is disposed on the second stub, and the length from the first feed point to the first end is 70% to 130% of the length from the grounding point to the second end.

8. The wearable device according to claim 7, characterized in that, The antenna structure also includes a switch, one end of which is coupled to the grounding point, and the other end of which is configured to be grounded; When the switch is in the off state, the radiator is used to generate the first resonance; When the switch is in the ON state, the radiator is used to generate a second resonance; The resonant frequency of the second resonance is greater than the resonant frequency of the first resonance.

9. The wearable device according to claim 7 or 8, characterized in that, The resonant frequency of the second resonance includes 5.8 GHz, and the total length of the first feed point to the first end, the ground point to the second end, and the third branch is between 25 mm and 45 mm.

10. The wearable device according to any one of claims 1-9, characterized in that, The housing includes an ear flap and an ear stem, with the ear flap disposed at one end of the ear stem; The antenna structure is disposed within the ear stem, and the length direction of the first branch is parallel to the length direction of the ear stem.

11. The wearable device according to claim 10, characterized in that, The ear sac is located at the top of the ear stem, the third branch is coupled to the end of the first branch near the ear sac, and the third branch is coupled to the end of the second branch near the ear sac.

12. An antenna structure for mounting in a wearable device, the wearable device being worn on a user's head, characterized in that, The antenna structure includes: A radiator, used to generate a first resonance, includes a first stub, a second stub, and a third stub; one end of the third stub is coupled to a first end of the first stub, and the other end of the third stub is coupled to a second end of the second stub; the first stub and the second stub are both located on the same side of the third stub and are arranged in parallel; the angle between the length direction of the third stub and the length direction of the first stub is 90°±15°; when the wearable device is worn on the user's head, the angle between the first stub and the horizontal plane is 30° to 80°; the length of the first stub is 70% to 130% of the length of the second stub; The first feed point is located on the first branch; The floor is spaced apart from the radiator.

13. The antenna structure according to claim 12, characterized in that, At the resonant frequency of the first resonance, the current strong point of the radiator is located on the third branch, the third branch has a midpoint in its length direction, and the distance between the current strong point and the midpoint is less than or equal to one-quarter of the length of the third branch.

14. The antenna structure according to claim 12 or 13, characterized in that, The currents on the first branch and the second branch are in opposite directions.

15. The antenna structure according to any one of claims 12-14, characterized in that, The resonant frequency of the first resonant includes 2.4 GHz, and the total length of the first stub, the second stub, and the third stub is between 30 mm and 55 mm.

16. The antenna structure according to claim 15, characterized in that, The length of the third branch is greater than 4.5 mm, and the distance between the first branch and the second branch is 0.2 mm to 5 mm.

17. The antenna structure according to any one of claims 12-16, characterized in that, The antenna structure also includes a coaxial line, and a second feed point is provided on the second branch. The first feed point is used to couple the inner conductor of the coaxial line, and the second feed point is used to couple the outer conductor of the coaxial line.

18. The antenna structure according to any one of claims 12-17, characterized in that, The antenna structure also includes a grounding point, which is disposed on the second stub, and the length from the first feed point to the third stub is 70% to 130% of the length from the grounding point to the third stub.

19. The antenna structure according to claim 18, characterized in that, The antenna structure also includes a switch, one end of which is coupled to the grounding point, and the other end of which is configured to be grounded; When the switch is in the off state, the radiator is used to generate the first resonance; When the switch is in the ON state, the radiator is used to generate a second resonance; The resonant frequency of the second resonance is greater than the resonant frequency of the first resonance.

20. The antenna structure according to claim 18 or 19, characterized in that, The resonant frequency of the second resonance includes 5.8 GHz, and the total length of the first feed point to the first end, the ground point to the second end, and the third branch is between 25 mm and 45 mm.

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