CN115442714B9

CN115442714B9 - Wireless earphone

Info

Publication number: CN115442714B9
Application number: CN202210985205.4A
Authority: CN
Inventors: 黄慧慈; 王岩; 罗健; 周大为
Original assignee: Fudan University; Honor Device Co Ltd
Current assignee: Fudan University; Honor Device Co Ltd
Priority date: 2022-08-17
Filing date: 2022-08-17
Publication date: 2023-12-15
Anticipated expiration: 2042-08-17
Also published as: CN115442714A; WO2024037047A1; CN115442714B

Abstract

The application provides a wireless earphone, which comprises an earphone antenna, an earplug part and an ear stem part. The earphone antenna comprises a main antenna unit and a resonance unit, wherein the main antenna unit comprises a first radiation branch arranged on the ear rod part. The resonance unit is arranged on the ear rod part and comprises a first metal branch. The first radiation branches are arranged opposite to the first metal branches and are arranged along the extending direction of the ear rod portion. The first radiating branch is located on a side away from the earplug portion, and the first metal branch is located on a side close to the earplug portion. The resonance unit is used for electric field coupling with the main antenna unit. According to the wireless earphone, the resonance unit is added to the main antenna unit, so that electric field coupling is generated between the main antenna unit and the resonance unit, and the parallel electric field component generated by the first radiation branch can be converted into the vertical electric field component, so that the parallel electric field component which can be absorbed by a human body is reduced, the vertical electric field component which is difficult to be absorbed by the human body is increased, and the radiation performance of the earphone antenna can be improved.

Description

Wireless earphone

Technical Field

The application relates to the technical field of wireless communication, in particular to a wireless earphone.

Background

Currently, wireless headsets, such as true wireless stereo (True Wireless Stereo, TWS) headsets, are rapidly becoming popular due to their miniaturization and portability, and are popular with the general public. When the wireless earphone is in communication with a terminal device (such as a mobile phone), two wireless earphones are not connected with the terminal device at the same time, but are divided into a driving earphone and a driven earphone, wherein the driving earphone is in communication connection with the terminal device, and the driven earphone is in communication connection with the driving earphone. It follows that it is important that the antenna design of the wireless headset has two points, one is the antenna efficiency under the head model and the other is the through-head gain. The efficiency of the head model determines the signal strength when the wireless earphone communicates with the terminal device, and the head penetration gain determines the signal strength between the two wireless earphones. The ear rod type TWS earphone antenna on the market at present is generally designed at the back of the ear rod, and is influenced by the extremely small size of the TWS earphone and the complex electromagnetic environment nearby the head of a person, compared with the antenna on the terminal equipment, the difference between the free space performance and the performance under the head mould is large. The efficiency reference value of the wireless earphone antenna on the head model is-12 dB, and the industry reference value of the head threading gain is about-30 dBi, so that the head model efficiency and the head threading gain of the current wireless earphone antenna still have great improvement space.

Disclosure of Invention

Compared with the earphone antenna of the ear rod TWS earphone in the traditional design scheme, the earphone antenna of the wireless earphone is greatly improved in antenna efficiency, threading gain, transmission coefficient S21 and other antenna performances, so that the communication performance between the wireless earphone and the terminal equipment and the communication performance between the two wireless earphones can be improved, and better use experience can be brought to users.

In a first aspect, the present application provides a wireless headset comprising a housing and a headset antenna, the housing comprising an ear stem portion, and a connection portion connected between the ear stem portion and the ear stem portion. The earphone antenna comprises a main antenna unit and a resonance unit, wherein the main antenna unit comprises a first radiator arranged on the ear stem part and a feed structure arranged on the connecting part or the earplug part. The first radiator comprises a first radiation branch arranged along the extending direction of the ear rod part, and a second radiation branch bent and extended from one end of the first radiation branch, which is close to the connecting part. The feed structure is electrically connected with an end of the second radiating branch remote from the first radiating branch. The resonance unit is arranged on the ear rod portion and comprises a first metal branch arranged along the extending direction of the ear rod portion. The first radiating branch is arranged opposite to the first metal branch, the first radiating branch is located at one side of the ear stem part away from the earplug part, and the first metal branch is located at one side of the ear stem part close to the earplug part. The resonance unit is used for performing electric field coupling with the main antenna unit.

According to the wireless earphone provided by the application, the resonance unit is added to the main antenna unit, and the first metal branch of the resonance unit is arranged on one side, close to the earplug part, of the ear rod part along the extending direction parallel to the ear rod part, so that electric field coupling is generated between the main antenna unit and the resonance unit, and therefore, a vertical electric field perpendicular to the human head can be generated between the first radiation branch and the human head, the purpose of converting a parallel electric field component generated by the first radiation branch into a vertical electric field component is achieved, and further, the parallel electric field component which can be absorbed by a human body and the vertical electric field component which is difficult to absorb by the human body are reduced, the surface wave radiated by the wireless earphone near the human head can be excited more, the radiation performance of the earphone antenna is improved, and finally, the aim of optimizing the experience and quality of a user using the wireless earphone is achieved.

In a possible implementation manner of the first aspect, the ear stem portion includes opposite first and second ends, and the first end of the ear stem portion is connected to the first end of the ear stem portion through the connection portion. The ear stem portion extends in a direction from a first end of the ear stem portion to a second end of the ear stem portion, and the ear stem portion extends in a direction from the first end of the ear stem portion to the second end of the ear stem portion, the direction of extension of the ear stem portion being perpendicular to the direction of extension of the ear stem portion. The extending direction of the second radiation branch is parallel to the extending direction of the earplug part.

In a possible implementation manner of the first aspect, the main antenna unit further includes a second radiator provided on the earplug portion. The feed structure is also electrically connected to an end of the second radiating branch remote from the first radiating branch.

The wireless earphone is characterized in that the first radiator is arranged in the ear rod part, the first radiation branch of the first radiator is arranged along the extending direction of the ear rod part, the second radiation branch of the first radiator is arranged along the extending direction parallel to the earplug part, and the first radiation branch is arranged on one side, far away from the earplug part, of the ear rod part, so that the length of the second radiation branch can be increased, and the length of the first radiation branch can be shortened. Meanwhile, the wireless earphone is further provided with the second radiator in the earplug part, so that the length of the first radiation branch can be further shortened. Because the extending directions of the second radiating branches and the second radiator are parallel to the extending direction of the earplug part and perpendicular to the extending directions of the first radiating branches and the ear rod part, namely perpendicular to the human head, the length of the first radiating branches can be shortened by increasing the second radiating branches and the second radiator, and the purposes of prolonging the vertical current path of the radiation current of the main antenna unit to increase the vertical electric field component of the electromagnetic wave radiated by the main antenna unit and shortening the parallel current path of the radiation current to reduce the parallel electric field component which can be absorbed by the human body are achieved, so that the surface wave radiated by the earphone antenna near the human head can be excited more, and the radiation performance of the main antenna unit is improved.

Further, the wireless earphone is provided with the feed structures which are respectively and electrically connected with the second radiation branch and the second radiator on the connecting part, so that the current strong point of the radiation current of the main antenna unit can be moved to the vertical current path of the radiation current, the vertical electric field component of the electromagnetic wave radiated by the main antenna unit can be further increased, the parallel electric field component which can be absorbed by a human body is reduced, and further, the surface wave radiated by the earphone antenna near the human head can be further excited, so that the radiation performance of the earphone antenna is further improved.

In a possible implementation manner of the first aspect, the extension direction of the second radiator is parallel to the extension direction of the earplug portion.

In a possible implementation manner of the first aspect, the resonant unit further includes a metal segment bent and extended from at least one end of the first metal branch, and the metal segment and the first metal branch together resonate the resonant unit in a target resonant frequency band, so that the resonant unit can be electrically coupled with the main antenna unit.

In a possible implementation manner of the first aspect, the ear stem portion includes opposite first and second ends, and the first end of the ear stem portion is connected to the first end of the ear stem portion through the connection portion. The ear stem portion extends in a direction from a first end of the ear stem portion to a second end of the ear stem portion, the ear stem portion extends in a direction from the first end of the ear stem portion to the second end of the ear stem portion, and the ear stem portion extends in a direction perpendicular to the ear stem portion; the extending direction of the metal segment is parallel to the extending direction of the earplug part.

In a possible implementation manner of the first aspect, the metal segment includes a second metal branch extending from an end of the first metal branch away from the connection portion in a bending manner, and a third metal branch extending from an end of the first metal branch near the connection portion in a bending manner.

The wireless earphone is characterized in that a metal section (a second metal branch and/or a third metal branch) which is bent and extended is arranged at least one end of a first metal branch of the resonance unit, and the extending direction of the metal section is parallel to the extending direction of the earplug part, so that the direction of current generated on the first metal branch can be converted from the direction parallel to the human head to the direction perpendicular to the human head through the metal section, the vertical electric field component of the earphone antenna can be further increased, and further the surface wave radiated by the earphone antenna near the human head can be further excited, so that the radiation performance of the main antenna unit is improved.

In a possible implementation manner of the first aspect, a length of the first radiator is approximately one quarter of a wavelength of electromagnetic waves in a bluetooth frequency band. Optionally, the length of the first radiator is approximately one quarter of the wavelength of electromagnetic waves in the WiFi frequency band.

In a possible implementation manner of the first aspect, a sum of a length of the first radiator and a length of the second radiator is approximately one half of a wavelength of electromagnetic waves in a bluetooth frequency band. Optionally, the sum of the length of the first radiator and the length of the second radiator is approximately one half of the wavelength of electromagnetic waves in the WiFi frequency band.

In a possible implementation manner of the first aspect, the sum of lengths of the metal branches included in the resonance unit is one quarter of a wavelength of the electromagnetic wave of the target resonance frequency band.

In a possible implementation manner of the first aspect, the ear stem portion includes a first housing and a second housing that are disposed opposite to each other, and the first housing and the second housing are detachably connected to enclose an accommodating cavity to load an internal structure of the wireless earphone, where the first housing is located on a side of the ear stem portion away from the ear plug portion, and the second housing is located on a side of the ear stem portion close to the ear plug portion. The first radiating branch is fixed on the first shell, and the first metal branch is fixed on the second shell.

In a possible implementation manner of the first aspect, the wireless earphone further includes a first circuit board disposed in the ear stem portion and a second circuit board disposed in the earplug portion. The first radiation branch knot and the second radiation branch knot are both arranged on the first circuit board, and the second radiator is arranged on the second circuit board. Therefore, the support used for bearing the first radiator and the second radiator is not required to be additionally arranged, the support is prevented from occupying the limited inner space of the wireless earphone, the structure of the wireless earphone is simplified, the integration level of devices of the wireless earphone is improved on the premise that the antenna can effectively transmit and receive signals, the structure of the wireless earphone is more compact, and the volume of the wireless earphone is reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below. It is apparent that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.

Fig. 1 is a schematic diagram of a wireless earphone in a wearing state according to an embodiment of the present application.

Fig. 2 is a schematic structural diagram of the wireless earphone shown in fig. 1.

Fig. 3 is an exploded view of the wireless headset shown in fig. 2.

Fig. 4 is a simplified structure diagram of an earphone antenna of the wireless earphone shown in fig. 2.

Fig. 5 is another simplified structure diagram of an earphone antenna of the wireless earphone shown in fig. 2.

Fig. 6 is a schematic diagram illustrating an operation principle of a main antenna unit of the earphone antenna shown in fig. 4.

Fig. 7 is a schematic diagram illustrating an operation principle of the earphone antenna shown in fig. 4.

Fig. 8 is a schematic diagram of an implementation size of the earphone antenna shown in fig. 4.

Fig. 9 is a schematic diagram of a simulation curve of the reflection coefficient and the transmission coefficient of the earphone antenna shown in fig. 8.

Fig. 10 is a schematic diagram showing a comparison of simulation results of radiation efficiency of a conventional ear stem type TWS earphone antenna and the earphone antenna shown in fig. 8.

Fig. 11 is a diagram showing a comparison of simulation results of system efficiency of the conventional ear-stem TWS earphone antenna and the earphone antenna shown in fig. 8.

Fig. 12 is a schematic diagram comparing transmission coefficient simulation results of a conventional ear-stem TWS earphone antenna with that of fig. 8 in the case of wearing wireless earphones in both ears.

Fig. 13 is a schematic diagram of a threading gain simulation result of the earphone antenna shown in fig. 8.

Description of the main reference signs

Wireless earphone	100
		Shell body	10
Earplug part	11
		First end	1101
Second end	1102
		Earplug shell	111
Ear stem	12
		First end	1201
Second end	1202
		First outer casing	121
Second housing	122
		Connecting part	13
Connection housing	131
		Main circuit board	21
Microphone	22
		Battery cell	23
Loudspeaker assembly	24
		First circuit board	25
Second circuit board	26
		Earphone antenna	30、30’
Main antenna unit	31
		First radiator	311
First radiation branch	3111
		Second radiation branch	3112
Second radiator	312
		Feed structure	313
Resonant unit	32、32’
		First metal branch	321
Second metal branch	322
		Third metal branch	323

The application will be further described in the following detailed description in conjunction with the above-described figures.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Wherein the drawings are for illustrative purposes only and are shown by way of illustration only and are not to be construed as limiting the application. It will be apparent that the described embodiments are only some, but not all, embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

Interpretation of the terms

And (3) vertical: the vertical defined in the present application is not limited to an absolute vertical intersection (angle of 90 degrees), and allows a non-absolute vertical intersection due to factors such as assembly tolerance, design tolerance, and structural flatness, and allows a deviation in a small angle range, for example, a range of 80 degrees to 100 degrees, to be understood as a vertical relationship.

Parallel: the parallelism defined in the present application is not limited to absolute parallelism, which is defined as being substantially parallel, allowing for cases that are not absolute parallelism due to factors such as assembly tolerances, design tolerances, structural flatness, etc., which would lead to a situation that is not absolute parallelism between, for example, the extension direction of the second radiating branch and the extension direction of the earplug part, but the present application is also defined as being parallel.

Currently, wireless headsets, such as true wireless stereo (True Wireless Stereo, TWS) headsets, are rapidly becoming popular due to their miniaturization and portability, and are popular with the general public. The wireless earphone can be connected with terminal equipment such as a mobile phone, a notebook computer, a tablet personal computer, a smart watch and the like in a wireless mode so as to be matched with the terminal equipment for use, and therefore audio services such as media, conversation and the like of the terminal equipment can be processed. When in use, a wireless earphone system is generally formed by two wireless earphones and a battery box, wherein the two wireless earphones can be respectively used as a left ear earphone and a right ear earphone, the left ear earphone can be matched with the left ear of a user for use, and the right ear earphone can be matched with the right ear of the user for use. A containing cavity is formed in the battery box to contain the two wireless earphones and charge the two wireless earphones.

The ear rod type TWS earphone antenna on the market at present is generally designed at the back of the ear rod, and is influenced by the extremely small size of the TWS earphone and the complex electromagnetic environment nearby the head of a person, compared with the antenna on the terminal equipment, the difference between the free space performance and the performance under the head mould is large. In order to overcome the influence caused by the extremely small size of an earphone antenna and the complicated electromagnetic environment near the head of a person, ensure the performance stability of the earphone antenna and improve the antenna efficiency of the earphone antenna as much as possible, the application provides a wireless earphone, wherein the wireless earphone is an earphone rod type earphone, and the earphone antenna of the wireless earphone is an earphone antenna based on surface waves and supports Bluetooth wireless communication or WiFi wireless communication, for example.

Referring to fig. 1 and fig. 2 together, fig. 1 and fig. 2 schematically show a schematic diagram of a wireless earphone 100 in a wearing state and a schematic diagram of a structure thereof according to an embodiment of the application. The wireless headset 100 may be a TWS headset. The wireless earphone 100 includes a housing 10, the housing 10 including an ear stem portion 11, an ear stem portion 12, and a connection portion 13 connected between the ear stem portion 12 and the ear stem portion 11. Wherein the extending direction of the ear stem portion 12 is perpendicular to the extending direction of the earplug portion 11. Specifically, as shown in fig. 2, the earplug portion 11 includes opposite first and second ends 1101, 1102, the ear stem portion 12 includes opposite first and second ends 1201, and the first end 1201 of the ear stem portion 12 is connected to the first end 1101 of the earplug portion 11 via the connection portion 13. The earplug portion 11 extends in the direction from the first end 1101 to the second end 1102, i.e., in the direction YO shown in fig. 2. The ear stem 12 extends in the direction of the first end 1201 to the second end 1202, i.e. in the direction ZO shown in fig. 2. Wherein the direction YO is perpendicular to the direction ZO. In some embodiments, the connection portion 13 may be bent and extended from the first end 1201 of the ear stem portion 12 and then connected to the first end 1101 of the earplug portion 11, that is, the connection portion 13 is integrally formed with the ear stem portion 12.

The ear plug portion 11 is intended to be fitted into the ear of a user. The earplug part 11 may also be referred to as an ear cup part and the ear stem part 12 may also be referred to as an ear stem part. When the wireless earphone 100 is worn by a user, at least part of the structure of the ear plug portion 11 is embedded in the user's ear, and the ear stem portion 12 is located outside the user's ear and near or in contact with the user's ear.

The ear stem 12 includes a first housing 121 and a second housing 122 disposed opposite to each other, and the first housing 121 and the second housing 122 are detachably connected to enclose a housing cavity for loading the internal structure of the wireless earphone 100. The first housing 121 is located at a side of the ear stem 12 away from the earplug 11, the second housing 122 is located at a side of the ear stem 12 close to the earplug 11, and the second housing 122 may be integrally formed with the connection housing 131 of the connection portion 13. The first housing 121 and the second housing 122 may be coupled together by, for example, a snap-fit connection, a threaded connection, etc., to facilitate later maintenance of the wireless headset 100.

Referring to fig. 2 and 3, the wireless earphone 100 further includes electronic components such as a main circuit board 21, a microphone 22, a battery 23, and a speaker assembly 24 disposed in the housing 10, wherein the main circuit board 21 may be disposed in the ear stem 12, and the main circuit board 21 may be used to dispose electronic components such as a main chip and a touch control assembly. The speaker assembly 24 is disposed within the earpiece housing 111 of the earpiece portion 11 and is configured to perform the audio playback function of the wireless headset 100. The battery 23 may be disposed within the ear bud portion 11 or the ear stem portion 12 for powering other electronic components of the wireless headset 100. In the present embodiment, the battery 23 is provided in the earplug portion 11.

It should be noted that fig. 2 and 3 only schematically illustrate some structural components included in the wireless earphone 100, and the actual configuration and location of these structural components are not limited by fig. 2 and 3, and the wireless earphone 100 may actually have more or fewer structural components with respect to the structural components illustrated in fig. 2 and 3, for example, the wireless earphone 100 may further include a sound pickup hole provided on the ear stem 12, a dust screen assembly provided in the ear stem 12, and the like.

Referring to fig. 3 and fig. 4 together, the wireless earphone 100 further includes an earphone antenna 30 disposed on/in the housing 10, the earphone antenna 30 includes a main antenna unit 31, and the main antenna unit 31 is configured to implement a wireless communication function of the wireless earphone 100. In this embodiment, the main antenna unit 31 includes a first radiator 311 and a feeding structure 313, wherein the first radiator 311 is disposed on the ear stem 12, and the feeding structure 313 is disposed on the connection portion 13 and electrically connected to one end of the first radiator 311. Alternatively, in another embodiment, the feeding structure 313 may also be provided on the earplug portion 11.

The first radiator 311 includes a first radiating branch 3111 and a second radiating branch 3112, wherein the first radiating branch 3111 is disposed along the extending direction of the ear stem 12, and the second radiating branch 3112 is bent and extended from an end of the first radiating branch 3111 near the connecting portion 13. In the present embodiment, the extending direction of the second radiating branch 3112 is perpendicular to the extending directions of the first radiating branch 3111 and the ear stem portion 12, and the extending direction of the second radiating branch 3112 is parallel to the extending direction of the earplug portion 11. The feed structure 313 is electrically connected to an end of the second radiating branch 3112 remote from the first radiating branch 3111.

In this embodiment, the main antenna unit 31 further includes a second radiator 312 disposed on the earplug portion 11, and the feeding structure is further electrically connected to an end portion of the second radiator 312 near the connection portion 13. The main antenna unit 31 further comprises a radio frequency module (not shown), and the first radiator 311 and the second radiator 312 are electrically connected to the radio frequency module through the feeding structure 313, respectively. In the present embodiment, the extending direction of the second radiator 312 is parallel to the extending direction of the earplug portion 11.

In the present embodiment, the structures of the first radiator 311, the second radiator 312, and the feeding structure 313 configure the main antenna unit 31 as a folded dipole antenna. In other embodiments, the main antenna unit 31 may not include the second radiator 312, and the structures of the first radiator 311 and the feed structure 313 configure the main antenna unit 31 as one monopole antenna.

In this embodiment, the main antenna unit 31 employs an FPC (Flexible Printed Circuit Board, flexible circuit board) antenna, and accordingly, the wireless earphone 100 further includes a first circuit board 25 disposed in the ear stem 12 and a second circuit board 26 disposed in the ear plug 11, where the first circuit board 25 and the second circuit board 26 are flexible circuit boards, the first radiator 311 (i.e. the first radiating branch 3111 and the second radiating branch 3112) may be disposed on the first circuit board 25, and the second radiator 312 may be disposed on the second circuit board 26.

Specifically, in one embodiment, the first circuit board 25 has a first ground layer formed thereon, the second circuit board 26 has a second ground layer formed thereon, the first ground layer may be used as the first radiating stub 3111 and the second radiating stub 3112, and the second ground layer may be used as the second radiator 312. That is, the wireless earphone 100 directly adopts the first ground layer of the first wiring board 25 located in the ear stem portion 12 as the first radiator 311 of the main antenna unit 31, and adopts the second ground layer of the second wiring board 26 located in the ear plug portion 11 as the second radiator 312 of the main antenna unit 31. In this way, the support for carrying the first radiator 311 and the second radiator 312 is not required to be additionally arranged, so that the support is prevented from occupying the limited internal space of the wireless earphone 100, the structure of the wireless earphone 100 is simplified, and the integration level of devices of the wireless earphone 100 is improved on the premise that the wireless earphone 100 can effectively transmit and receive signals, so that the structure of the wireless earphone 100 is more compact, and the volume of the wireless earphone 100 is reduced.

It will be appreciated that the first circuit board 25 may further be provided with a first power supply line and a first signal line of a chip, a sensor, the microphone 22, etc., and the first ground layer provides a reference ground for the first power supply line and the first signal line. The second circuit board 26 may further be provided with a second power supply line and a second signal line of the battery 23, the chip, the sensor, the speaker assembly 24, etc., and the second ground layer provides a reference ground for the second power supply line and the second signal line.

In order to ensure that the radio frequency signals radiated by the first radiator 311 and the second radiator 312 are not transmitted to the reference ground of other electronic components, the first ground layer and the second ground layer may be isolated from the reference ground of the electronic components in the housing 10 of the wireless headset 100 by an isolation structure, respectively. The isolation structure may be an inductor, a capacitor, a resistor, or a combination thereof, and the reference ground of the electronic component refers to the ground terminal of the electronic component. The first ground layer and the second ground layer may not be electrically connected to the ground layer of the main circuit board 21. The specific structure related to the method can be adopted in the prior art, and is not described herein.

In another embodiment, a first metal patch may be disposed on the first circuit board 25 to form the first radiator 311, and a second metal patch may be disposed on the second circuit board 26 to form the second radiator 312.

In other embodiments, the main antenna unit 31 may be a ceramic antenna or a laser-formed antenna (Laser Direct structuring, LDS antenna), or the like.

In this embodiment, the feeding structure 313 includes feeding ports (not shown) electrically connected to one end of the first radiator 311 near the connection portion 13, one end of the second radiator 312 near the connection portion 13, and the rf module, respectively.

To ensure the integrity of the radiator of the main antenna unit 31, in some embodiments, the second radiating branch 3112 may extend from the ear stem portion 12 to the connection portion 13 or the ear plug portion 11 to be electrically connected to the second radiator 312, and the feeding port may be provided on the second radiating branch 3112. Alternatively, in some embodiments, the second radiator 312 may extend from the earplug portion 11 to the connection portion 13 or the ear stem portion 12 to be electrically connected to the second radiating branch 3112, and the feeding port may be provided on the second radiator 312. Alternatively, in some embodiments, the second radiating branch 3112 may extend from the ear stem portion 12 to the connection portion 13, the second radiator 312 may extend from the earplug portion 11 to the connection portion 13 and be electrically connected to the second radiating branch 3112, and the feeding port may be provided at a connection between the second radiator 312 and the second radiating branch 3112. Optionally, in some embodiments, the wireless earphone 100 may further include a third circuit board (not shown) disposed in the connection portion 13, where a third ground layer is formed on the third circuit board to form a third radiator of the main antenna unit 31, or a third metal patch is disposed on the third circuit board to form a third radiator of the main antenna unit 31, where the third radiator is electrically connected between an end of the first radiator 311 near the connection portion 13 and an end of the second radiator 312 near the connection portion 13, and the feeding port may be disposed on the third radiator. The connection manner between the second radiating stub 3112 and the second radiator 312 is not particularly limited in the present application.

In one embodiment, the radio frequency module may be disposed on the second circuit board 26, and the feeding port may be electrically connected to the radio frequency module on the second circuit board 26 through a metal spring plate, a metal connection post, or other connection elements, so as to realize transmission of a transceiver signal. Alternatively, in another embodiment, the radio frequency module may be disposed on the main circuit board 21, and the feeding structure 313 may further include a feeding transmission line (not shown), where one end of the feeding transmission line is electrically connected to the feeding port, and the other end extends to the ear stem 12 to be electrically connected to the radio frequency module on the main circuit board 21.

In this embodiment, the wireless earphone 100 is a bluetooth wireless earphone supporting bluetooth wireless communication, and accordingly, in the embodiment in which the main antenna unit 31 includes the second radiator 312, the structures of the first radiator 311, the second radiator 312, and the feeding structure 313 configure the main antenna unit 31 as a folded dipole antenna, where the sum of the length of the first radiator 311 and the length of the second radiator 312 is approximately one half of the electromagnetic wave wavelength of the bluetooth frequency band; in an embodiment in which the main antenna unit 31 does not include the second radiator 312, the first radiator 311 and the feeding structure 313 are configured to configure the main antenna unit 31 as a monopole antenna, and the length of the first radiator 311 is approximately one quarter of the wavelength of electromagnetic waves in the bluetooth band.

In another embodiment, the wireless earphone 100 is a WiFi wireless earphone supporting WiFi wireless communication, and accordingly, in an embodiment in which the main antenna unit 31 includes the second radiator 312, the sum of the length of the first radiator 311 and the length of the second radiator 312 is approximately one half of the wavelength of electromagnetic waves in the WiFi frequency band; in an embodiment where the main antenna unit 31 does not include the second radiator 312, the length of the first radiator 311 is approximately one quarter of the wavelength of the electromagnetic wave in the WiFi band.

It should be noted that, by "approximately" is meant that the length of the radiator of the main antenna unit 31 is approximately equal to one half or one quarter of the electromagnetic wave wavelength of the bluetooth frequency band or the WiFi frequency band, that is, the difference between the length of the radiator of the main antenna unit 31 and one half or one quarter of the electromagnetic wave wavelength of the bluetooth frequency band or the WiFi frequency band is within a preset range, and in a specific implementation, the electrical length of the radiator of the main antenna unit 31 may be made equal to one half or one quarter of the electromagnetic wave wavelength of the bluetooth frequency band or the WiFi frequency band by adjusting a matching circuit or the like, but the physical length of the radiator of the main antenna unit 31 is not necessarily exactly equal to one half or one quarter of the electromagnetic wave wavelength of the bluetooth frequency band or the WiFi frequency band.

In this embodiment, the earphone antenna 30 further includes a resonance unit 32 disposed on the ear stem 12, and the resonance unit 32 includes a first metal branch 321 disposed along the extending direction of the ear stem 12. The first radiating branch 3111 is disposed opposite to the first metal branch 321, and the first radiating branch 3111 is located at a side of the ear stem 12 away from the earplug 11, and the first metal branch 321 is located at a side of the ear stem 12 close to the earplug 11.

In one embodiment, the first radiating stub 3111 is secured to the first housing 121 and the first metallic stub 321 is secured to the second housing 122. Specifically, the first housing 121 may serve as a support for the first circuit board 25 to fix the first circuit board 25, thereby fixing the first radiating stub 3111 to the first housing 121 such that the first radiating stub 3111 is located on a side of the ear stem portion 12 remote from the earplug portion 11. The second housing 122 may serve as a support for the first metal stem 321 to secure the first metal stem 321 such that the first metal stem 321 is located on a side of the ear stem portion 12 adjacent to the earplug portion 11. The first metal stem 321 may be disposed on the inner side, the outer side of the second housing 122 or may be a part of the second housing 122, which is not limited in the present application.

In this embodiment, the resonance unit 32 is configured to perform electric field coupling with the main antenna unit 31. Specifically, the target resonant frequency band of the resonant unit 32 is close to and slightly higher than the operating frequency band of the main antenna unit 31, and the sum of lengths of the metal branches included in the resonant unit 32 is one half of the wavelength of the electromagnetic wave of the target resonant frequency band.

The length of the first metal branch 321 may not be one quarter of the wavelength of the electromagnetic wave of the target resonant frequency band due to the extremely small size of the ear stem 12. In order to extend the electrical length of the first metal branch 321 so as to enable the resonant unit 32 to resonate in the target resonant frequency band, the resonant unit 32 may further include a metal section bent and extended from at least one end of the first metal branch 321, and the metal section and the first metal branch 321 together enable the resonant unit 32 to resonate in the target resonant frequency band, so that the resonant unit 32 can generate electric field coupling with the main antenna unit 31.

In this embodiment, the metal segment may include a second metal branch 322 bent and extended from an end of the first metal branch 321 far from the connection portion 13, and a third metal branch 323 bent and extended from an end of the first metal branch 321 near to the connection portion 13.

In some embodiments, the direction of extension of the metal segments (i.e., the second metal stem 322 and the third metal stem 323) is perpendicular to the direction of extension of the first metal stem 321 and the ear stem 12, and parallel to the direction of extension of the earplug 11. In other embodiments, the metal segments may also extend in other directions.

When the second metal branch 322 or the third metal branch 323 extending in a bending manner is disposed only at one end of the first metal branch 321, the electrical length of the first metal branch 321 may be extended to one fourth of the electromagnetic wave wavelength of the target resonant frequency band, as shown in fig. 5, the resonant unit 32 'of the earphone antenna 30' may be disposed only on the first metal branch 321 and the second metal branch 322. Similarly, in other embodiments, the resonant unit 32 'of the earphone antenna 30' may be provided with only the first metal branch 321 and the third metal branch 323.

The operation of the earphone antenna 30 will be described with reference to fig. 6 and 7.

Referring to fig. 6, when the main antenna unit 31 is fed to radiate electromagnetic waves, radiation currents are generated on both the first radiator 311 and the second radiator 312. Wherein the radiation current is transmitted along the extension direction of the first radiator 311 and the second radiator 312. When the wireless earphone 100 is in a worn state, the ear stem portion 12 is located outside and near or in contact with the user's ear due to at least a portion of the structure of the ear plug portion 11 being embedded in the user's ear. Thus, the ear stem portion 12 is generally parallel to the human head. Thus, the current direction on both the second radiating branch 3112 and the second radiator 312 is perpendicular to the human head, while the current direction on the first radiating branch 3111 is parallel to the human head. Accordingly, the electric fields generated by the second radiating branch 3112 and the second radiator 312 are all mainly perpendicular to the human head, and the electric field generated by the first radiating branch 3111 is mainly parallel to the human head.

According to basic electromagnetic theory, surface waves are electromagnetic waves that propagate along interfaces of different media. Near the wireless earphone 100 and the human head, if the electric field component of the electromagnetic wave radiated by the earphone antenna is mainly represented as a parallel component at the interface between the air and the human head, the attenuation is larger; if the electric field component is predominantly represented as a vertical component, the attenuation is smaller. When electromagnetic waves represent surface waves of the interface between air and human head, the parallel electric field component is easily absorbed by human head/human body, while the vertical electric field component is not easily absorbed by human body, and the increase of the vertical electric field component can obviously optimize the radiation performance of the antenna. It should be noted that the "vertical component" or the "vertical electric field component" as used herein refers to an electric field component perpendicular to the human head/body, and the "parallel component" or the "parallel electric field component" as used herein refers to an electric field component parallel to the human head/body.

In the present embodiment, the wireless earphone 100 can increase the length of the second radiation branch 3112 and shorten the length of the first radiation branch 3111 by disposing the first radiator 311 in the ear stem portion 12, disposing the first radiation branch 3111 of the first radiator 311 in the extending direction of the ear stem portion 12, disposing the second radiation branch 3112 of the first radiator 311 in parallel with the extending direction of the ear plug portion 11, and disposing the first radiation branch 3111 on the side of the ear stem portion 12 away from the ear plug portion 11; meanwhile, the wireless earphone 100 further provides the second radiator 312 in the earplug portion 11, so that the length of the first radiating stub 3111 can be further shortened. Since the extending directions of the second radiating branch 3112 and the second radiator 312 are parallel to the extending direction of the earplug portion 11 and perpendicular to the extending directions of the first radiating branch 3111 and the ear stem portion 12, i.e., perpendicular to the human head, the length of the first radiating branch 3111 can be shortened by increasing the lengths of the second radiating branch 3112 and the second radiator 312, so that the purpose of extending the vertical current path of the radiation current of the main antenna unit 31 to increase the vertical electric field component of the electromagnetic wave radiated by the main antenna unit 31 and shortening the parallel current path of the radiation current to reduce the parallel electric field component that can be absorbed by the human body can be achieved, and further, the surface wave radiated by the earphone antenna 30 near the human head can be excited more, so that the radiation performance of the main antenna unit 31 can be improved.

Further, the wireless earphone 100 may further increase the vertical electric field component of the electromagnetic wave radiated by the main antenna unit 31, reduce the parallel electric field component that can be absorbed by the human body, and further excite the surface wave radiated by the earphone antenna 30 near the human head by providing the feeding structure 313 electrically connected to the second radiating branch 3112 and the second radiator 312 on the connection portion 13, so as to further increase the radiation performance of the earphone antenna 30.

In addition, since the electric field generated by the first radiating branch 3111 of the first radiator 311 is parallel to the human head, a part of energy of the electromagnetic wave radiated from the main antenna unit 31 may be absorbed by the human body. In order to reduce the parallel electric field component that can be absorbed by the human body to improve the radiation performance of the main antenna unit 31, it is necessary to excite as much as possible the perpendicular electric field component that is perpendicular to the human head to improve the effective component of the surface wave electric field component.

Referring to fig. 7, the wireless earphone 100 adds a resonance unit 32 to the main antenna unit 31, and sets a first metal branch 321 of the resonance unit 32 on a side of the ear stem 12 near the ear stem 11 along a direction parallel to the extending direction of the ear stem 12, and the first metal branch 321 blocks between the first radiating branch 3111 and the head, so as to generate electric field coupling between the main antenna unit 31 and the resonance unit 32, thereby generating a vertical electric field perpendicular to the ear stem 12 and the head between the first radiating branch 3111 and the head, achieving the purpose of converting the parallel electric field component generated by the first radiating branch 3111 into a vertical electric field component, further reducing the parallel electric field component that can be absorbed by the human body and increasing the vertical electric field component that is difficult to be absorbed by the human body, further exciting the surface wave radiated by the earphone antenna 30 near the head, further improving the radiation performance of the main antenna unit 31, and finally optimizing the user experience of the wireless earphone 100.

Further, the wireless earphone 100 can further increase the vertical electric field component of the earphone antenna 30 by providing a metal segment (second metal branch 322 and/or third metal branch 323) extending in a bent manner at least at one end of the first metal branch 321 of the resonance unit 32, and setting the extending direction of the metal segment to be parallel to the extending direction of the ear plug portion 11, and can further excite the surface wave radiated by the earphone antenna 30 near the head of a person to improve the radiation performance of the main antenna unit 31 by converting the direction of the current generated on the first metal branch 321 from the direction parallel to the head of the person to the direction perpendicular to the head of the person, as shown in fig. 7, in addition to the extension of the electric length of the first metal branch 321 by the metal segment.

In summary, the earphone antenna 30 provided by the present application is a TWS earphone antenna based on surface waves.

Taking the operation of the earphone antenna 30 of the wireless earphone 100 in the bluetooth frequency band as an example, the antenna performance parameters of the earphone antenna 30 of the wireless earphone 100, such as the antenna efficiency, the threading gain, the transmission coefficient S21, etc., are simulated and analyzed.

Referring to fig. 7 and 8 together, in one embodiment, the length L1 of the first radiating branch 3111 is set to 25mm, the distance L2 from the first radiating branch 3111 to the feeding structure 313 (i.e., the length of the second radiating branch 3112) is set to 6.4mm, the distance L3 from the end of the second radiator 312 away from the connection portion 13 to the feeding structure 313 (i.e., the length of the second radiator 312) is set to 10mm, the length L4 of the first metal branch 321 is set to 30mm, the lengths L5 of the second metal branch 322 and the third metal branch 323 are both set to 3mm, the feeding port adopts a discrete port mode, and the input impedance is designed to be 50 ohms. It should be noted that the above size parameters or matching parameters are only design parameters of one embodiment of the ultra-small TWS headset antenna operating in the bluetooth frequency band, and the design of the headset antenna 30 is not limited to the above size parameters or matching parameters, and those skilled in the art may modify or adjust the size parameters or matching element parameters according to actual design requirements, for example, those skilled in the art may modify the size parameters or matching element parameters to design the headset antenna of the wireless headset supporting other wireless communication modes. All technical variations made according to the technical scheme of the application are covered in the protection scope of the application.

Fig. 9-12 are simulation diagrams of the antenna performance parameters of the earphone antenna 30 designed with the size parameters shown in fig. 8 after matching.

Referring to fig. 9, fig. 9 is a schematic diagram of a simulation curve of the reflection coefficient S11 and the transmission coefficient S21 (which may also be referred to as a coupling coefficient) of the earphone antenna 30 shown in fig. 8. As can be seen from fig. 9, after the earphone antenna 30 designed with the size shown in fig. 8 is matched, the impedance bandwidth of-6 dB of the earphone antenna 30 is 2367-2558MHz, and the bandwidth completely covers the bluetooth frequency band 2404-2484MHz. As can be seen from the curve of the reflection coefficient S11, the central frequency point of the operation of the earphone antenna 30 is 2450MHz. When both ears of a human body wear the wireless earphone, the transmission coefficient S21 of the earphone antenna 30 at the 2450MHz central frequency point is-52.5 dB, so that the design requirement of the earphone antenna 30 can be met.

Referring to fig. 10, fig. 10 is a schematic diagram showing the comparison of the simulation results of the radiation efficiency of the conventional ear-stem TWS earphone antenna and the earphone antenna 30 shown in fig. 8. Wherein, the conventional ear stem type TWS earphone antenna locates the feeding structure 313 at an end of the ear stem portion 12 far from the connection portion 13, locates the first radiating branch 3111 at a side of the ear stem portion 12 near the earplug portion 11, and does not locate the second radiating branch 3112 and the resonance unit 32.

As can be seen from fig. 10, the radiation efficiency of the ear rod type TWS earphone antenna of the conventional design at the center frequency point 2450MHz is-9.3 dB. After the earphone antenna 30 designed with the size shown in fig. 8 is matched, the radiation efficiency of the earphone antenna 30 at 2450MHz of the center frequency point is-5.9 dB, and compared with the radiation efficiency of the ear rod type TWS earphone antenna in the conventional design, the radiation efficiency of the earphone antenna 30 is improved by about 3-4dB, and therefore, the radiation efficiency of the earphone antenna 30 is obviously improved.

Referring to fig. 11, fig. 11 is a schematic diagram illustrating comparison of simulation results of system efficiency of a conventional ear-stem TWS earphone antenna and the earphone antenna 30 shown in fig. 8. As can be seen from fig. 11, the average system efficiency of the ear-rod TWS earphone antenna of the conventional design in the bluetooth band bandwidth is-9.3 dB. After the earphone antenna 30 designed with the size shown in fig. 8 is matched, the average system efficiency of the earphone antenna 30 in the bluetooth frequency band is about-6.1 dB, and compared with the system efficiency of the ear rod type TWS earphone antenna in the conventional design, the system efficiency of the earphone antenna 30 is improved by about 3-4dB, and it can be seen that the system efficiency of the earphone antenna 30 is significantly improved.

Referring to fig. 12, fig. 12 is a schematic diagram showing a comparison of transmission coefficient simulation results of a conventional ear-rod type TWS earphone antenna and the earphone antenna 30 shown in fig. 8 in a case of wearing wireless earphones in both ears. As can be seen from fig. 11, the transmission coefficient S21 of the ear-rod TWS earphone antenna of the conventional design at the center frequency point 2450MHz is-62.6 dB. After the earphone antenna 30 designed with the size shown in fig. 8 is matched, the transmission coefficient S21 of the earphone antenna 30 at the center frequency point 2450MHz is-52.5 dB, which is improved by about 10dB compared with the transmission coefficient of the ear rod type TWS earphone antenna in the conventional design scheme, and the design requirement of the earphone antenna 30 can be satisfied.

Referring to fig. 13, fig. 13 is a schematic diagram showing the threading gain simulation result of the earphone antenna 30 shown in fig. 8. As can be seen from fig. 13, the minimum gain value of the earphone near the ear on the non-wearing side reaches-23.4 dBi, which is greater than the industry reference value-30 dBi. The maximum SAR (Specific Absorption Rate, absorption ratio) value of the human head is calculated to be 0.45W/kg@1g by simulation software, which is smaller than the reference value 1.1W/kg@1g in the industry, namely, the SAR value of the earphone antenna 30 is reduced, so that compared with the ear rod type TWS earphone antenna with the traditional design scheme, the earphone antenna 30 shown in fig. 8 is also greatly improved in head penetration gain, and the design requirement of the earphone antenna 30 can be met.

As can be seen from analysis, compared with the earphone antenna of the ear stem TWS earphone according to the conventional design, the earphone antenna 30 of the wireless earphone 100 provided by the present application has the advantages that the second radiator 312 and the second radiating branch 3112 are disposed in the ear stem 11 and the ear stem 12 along the extending direction parallel to the ear stem 11, so that the feeding point of the main antenna unit 31 is moved from the bottom of the ear stem far from the ear stem to the connection portion 13 between the ear stem 11 and the ear stem 12, and the resonance unit 32 is added between the first radiating branch 3111 of the main antenna unit 31 and the human head, so that the antenna performance of the earphone antenna 30 such as antenna efficiency, head-penetrating gain, transmission coefficient S21, etc. is significantly improved, the antenna performance of the wireless earphone 100 is significantly optimized, the use security of the wireless earphone 100 is improved, and the wireless earphone 100 is further ensured to have good connection performance, so that the communication performance between the wireless earphone 100 and terminal equipment is improved, and the communication performance between the two wireless earphone 100 can be better.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any changes or substitutions that may be easily conceived by those skilled in the art within the scope of the present application should be included in the scope of the present application. Therefore, the protection scope of the application is subject to the protection scope of the claims.

Claims

1. A wireless headset, comprising:

a housing including an earplug portion, an ear stem portion, and a connection portion connected between the ear stem portion and the earplug portion; and

an earphone antenna, comprising:

a main antenna unit including a first radiator provided on the ear stem portion, and a feeding structure provided on the connection portion or the earplug portion; the first radiator comprises a first radiation branch arranged along the extending direction of the ear rod part, and a second radiation branch bent and extended from one end of the first radiation branch close to the connecting part; the extending direction of the second radiation branch is perpendicular to the extending directions of the first radiation branch and the ear stem part, the extending direction of the second radiation branch is parallel to the extending direction of the earplug part, and the feed structure is electrically connected with the end part of the second radiation branch, which is far away from the first radiation branch; and

the resonance unit is arranged on the ear rod part and comprises a first metal branch knot arranged along the extending direction of the ear rod part; the first radiation branch is arranged opposite to the first metal branch, the first radiation branch is positioned at one side of the ear stem part far away from the earplug part, and the first metal branch is positioned at one side of the ear stem part near to the earplug part;

The resonance unit is used for performing electric field coupling with the main antenna unit.

2. The wireless headset of claim 1, wherein the ear stem portion includes opposing first and second ends, the ear stem portion first end being connected to the ear stem portion first end by the connection portion;

the ear stem portion extends in a direction from a first end of the ear stem portion to a second end of the ear stem portion, and the ear stem portion extends in a direction from the first end of the ear stem portion to the second end of the ear stem portion, the direction of extension of the ear stem portion being perpendicular to the direction of extension of the ear stem portion.

3. The wireless headset of claim 2, wherein the main antenna unit further comprises a second radiator disposed on the ear plug portion, the feed structure further being electrically connected to an end of the second radiator proximate the connection portion.

4. A wireless headset according to claim 3, wherein the direction of extension of the second radiator is parallel to the direction of extension of the ear plug portion.

5. The wireless headset of claim 1, wherein the resonating unit further comprises a metal segment bent from at least one end of the first metal stub, the metal segment and the first metal stub together resonating the resonating unit at a target resonating frequency band, thereby enabling the resonating unit to be electrically coupled with the main antenna unit.

6. The wireless headset of claim 5, wherein the ear stem portion includes opposing first and second ends, the ear stem portion first end being connected to the ear stem portion first end by the connection portion;

the ear stem portion extends in a direction from a first end of the ear stem portion to a second end of the ear stem portion, the ear stem portion extends in a direction from the first end of the ear stem portion to the second end of the ear stem portion, and the ear stem portion extends in a direction perpendicular to the ear stem portion; the extending direction of the metal segment is parallel to the extending direction of the earplug part.

7. The wireless headset of claim 6, wherein the metal segment includes a second metal branch extending from an end of the first metal branch distal from the connection portion and a third metal branch extending from an end of the first metal branch proximal to the connection portion.

8. The wireless headset of claim 1 or 2, wherein the length of the first radiator is approximately one quarter of the wavelength of electromagnetic waves in the bluetooth band; or alternatively

The length of the first radiator is approximately one quarter of the wavelength of electromagnetic waves in the WiFi frequency band.

9. The wireless headset of claim 3, wherein the sum of the length of the first radiator and the length of the second radiator is approximately one half of the wavelength of electromagnetic waves in the bluetooth band; or alternatively

The sum of the length of the first radiator and the length of the second radiator is approximately one half of the wavelength of electromagnetic waves in the WiFi frequency band.

10. The wireless headset of claim 7, wherein the resonating unit comprises a sum of lengths of metal branches that is one half of a wavelength of electromagnetic waves of the target resonating frequency band.

11. The wireless headset of claim 1, wherein the ear stem portion comprises oppositely disposed first and second housings removably connected to enclose a receiving cavity for receiving an internal structure of the wireless headset, wherein the first housing is located on a side of the ear stem portion remote from the ear stem portion and the second housing is located on a side of the ear stem portion proximate to the ear stem portion;

the first radiating branch is fixed on the first shell, and the first metal branch is fixed on the second shell.

12. The wireless headset of claim 3, further comprising a first wiring board disposed within the ear stem portion and a second wiring board disposed within the ear bud portion;

the first radiation branch knot and the second radiation branch knot are both arranged on the first circuit board, and the second radiator is arranged on the second circuit board.