WO2024037051A1

WO2024037051A1 - Wireless earphone

Info

Publication number: WO2024037051A1
Application number: PCT/CN2023/092011
Authority: WO
Inventors: 黄慧慈; 王岩; 罗健; 周大为
Original assignee: 荣耀终端有限公司; 复旦大学
Priority date: 2022-08-17
Filing date: 2023-05-04
Publication date: 2024-02-22
Also published as: CN115377663B; CN115377663A

Abstract

The present application provides a wireless earphone, comprising an earphone antenna, an earbud portion, and a stem portion. The earphone antenna comprises a main antenna unit and a resonance unit, and the main antenna unit comprises a first radiation branch provided on the stem portion. The resonance unit is arranged on the stem portion and comprises a first metallic branch. The first radiation branch and the first metallic branch are oppositely arranged and both are arranged along the extending direction of the stem portion. The first radiation branch is located on the side away from the earbud portion, and the first metallic branch is located on the side close to the earbud portion. The resonance unit is used for performing 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 the 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 a vertical electric field component, thereby reducing the parallel electric field component that can be absorbed by a human body and increasing the vertical electric field component that is difficultly absorbed by the human body, and then improving the radiation performance of the earphone antenna.

Description

Wireless Headphones

This application claims priority to the patent application filed with the China Patent Office on August 17, 2022, with application number 202210991770.1 and the application name "Wireless Headset", the entire content of which is incorporated into this application by reference.

Technical field

The present application relates to the field of wireless communication technology, and in particular to a wireless earphone.

Background technique

Currently, wireless earphones, such as True Wireless Stereo (TWS) earphones, are rapidly gaining popularity due to their miniaturization and portability, and are deeply loved by the public. When wireless headsets communicate with a terminal device (such as a mobile phone), generally two wireless headsets are not connected to the terminal device at the same time. Instead, they are divided into active headsets and slave headsets. The active headset communicates with the terminal device and the slave headset Communication connection with active headset. It can be seen that there are two very important points in the antenna design of wireless headphones. One is the antenna efficiency under the head mold, and the other is the through-head gain. Among them, the headform efficiency determines the signal strength when the wireless earphones communicate with the terminal device, while the head-through gain determines the signal strength between the two wireless earphones. The ear-rod type TWS headset antenna currently on the market is generally designed on the back of the ear rod. Due to the extremely small size of TWS headphones and the impact of the complex electromagnetic environment near the human head, compared with the antenna on the terminal device, whether it is free There is a big gap between the space performance and the performance under the head mold. Among them, the reference value of the efficiency of the wireless headphone antenna on the head mold is -12dB, and the industry reference value of the head-through gain is about -30dBi. It can be seen that the head-form efficiency and head-through gain of the current wireless headphone antenna are still greatly improved. space.

Contents of the invention

The present application provides a wireless earphone. Compared with the earphone antenna of the traditional ear-bar type TWS earphone, the earphone antenna of the wireless earphone has greater antenna performance such as antenna efficiency, head-through gain, and transmission coefficient S21. The improvement can improve the communication performance between the wireless headset and the terminal device, and improve the communication performance between the two wireless headsets, which can bring a better user experience to the user.

In a first aspect, the present application provides a wireless earphone, including a housing and an earphone antenna. The housing includes an earplug part and an earrod part connected to the earplug part. The earphone antenna includes a main antenna unit and a resonant unit, and the main antenna unit includes a first radiator and a feed structure. The first radiator includes first radiation branches arranged along the extending direction of the ear bar portion. The first radiating branch and the feed structure are both disposed on the ear rod portion, and the feeding structure is electrically connected to one end of the first radiating branch. The resonant unit is provided on the ear bar part, and the resonant unit includes a first metal branch arranged along the extension direction of the ear bar part. The first radiating branch is arranged opposite to the first metal branch, and the first radiating branch is located on a side of the ear rod part away from the earplug part, and the first metal branch is located on the ear rod part. The side close to the earplug part. Wherein, the resonant unit is used for electric field coupling with the main antenna unit.

The wireless headset provided by the present application adds a resonant unit to the main antenna unit, and disposes the resonant unit on the side of the ear bar portion close to the earplug portion in a direction parallel to the extension direction of the ear bar portion. The first metal branch causes electric field coupling between the main antenna unit and the resonant unit, thereby generating a vertical electric field perpendicular to the human head between the first radiating branch and the human head, achieving the goal of coupling the first The parallel electric field component generated by the radiating branches is converted into The purpose of the vertical electric field component is to reduce the parallel electric field component that can be absorbed by the human body and increase the vertical electric field component that is difficult to be absorbed by the human body, which can further stimulate the surface waves radiated by the headphone antenna near the human head, and further improve the The radiation performance of the main antenna unit is finally achieved to optimize the user experience and quality of using the wireless headset.

In a possible implementation manner of the first aspect, the first radiator further includes a second radiating branch bent and extended from an end of the first radiating branch away from the feed structure, and the second radiating branch is configured to on the ear rod part.

In a possible implementation manner of the first aspect, the earplug part includes an opposite first end and a second end, the ear rod part includes an opposite first end and a second end, and the first end of the ear rod part Connected to the first end of the earplug part. The earplug part extends in a direction from the first end of the earplug part to the second end of the earplug part, and the ear rod part extends along the direction from the first end of the ear rod part to the second end of the ear rod part. The extension direction of the ear rod part is perpendicular to the extension direction of the earplug part, and the extension direction of the second radiating branch is parallel to the extension direction of the earplug part.

In a possible implementation manner of the first aspect, the power feeding structure is provided at an end of the ear rod part away from the earplug part. The first radiator further includes a third radiating branch. The third radiating branch is provided on the earplug part and is electrically connected to an end of the second radiating branch away from the first radiating branch. The extension direction of the third radiating branches is parallel to the extension direction of the earplug part.

The wireless earphone disposes the first radiation branch parallel to the extension direction of the earplug part by arranging the first radiation branch of the first radiator in the ear rod part along the extension direction of the ear rod part. the second radiating branch of the body, and the first radiating branch is arranged on the side of the ear rod part away from the earplug part, so that the length of the second radiating branch can be increased and the first radiating branch can be shortened. At the same time, the wireless earphone is also provided with the third radiating branch in the earbud part, so that the length of the first radiating branch can be further shortened. Since the extension directions of the second radiating branches and the third radiating branches 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, that is, perpendicular to Therefore, the length of the first radiating branch can be shortened by increasing the second radiating branch and the third radiating branch, so as to extend the vertical current path of the radiation current of the main antenna unit to increase the length of the main antenna. The vertical electric field component of the electromagnetic wave radiated by the unit, and the purpose of shortening the parallel current path of the radiation current to reduce the parallel electric field component that can be absorbed by the human body, thereby being able to excite more surface waves radiated by the headphone antenna near the human head, to improve the radiation performance of the main antenna unit.

In a possible implementation manner of the first aspect, the main antenna unit further includes a second radiator provided on the ear rod portion, and the feed structure is further electrically connected to one end of the second radiator.

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 jointly cause the resonance The unit resonates in the target resonance frequency band, thereby enabling the resonant unit to perform electric field coupling with the main antenna unit.

In a possible implementation manner of the first aspect, the earplug part includes an opposite first end and a second end, the ear rod part includes an opposite first end and a second end, and the first end of the ear rod part Connected to the first end of the earplug part. The earplug part extends in a direction from the first end of the earplug part to the second end of the earplug part, and the ear rod part extends along the direction from the first end of the ear rod part to the second end of the ear rod part. The extension direction of the ear rod part is perpendicular to the extension direction of the earplug part. The extension direction of the metal section is parallel to the extension direction of the earplug part.

In a possible implementation manner of the first aspect, the metal segment includes a second metal branch bent and extended from an end of the first metal branch away from the earplug part and a second metal branch extending from the first metal branch close to the earplug. One end of the part is bent The third extended metal branch.

The wireless earphone is configured by arranging bent and extended metal segments (second metal stubs and third metal stubs) at both ends of the first metal stub of the resonant unit, and connecting the second metal stub and the third metal stub. The extension directions of the metal branches are all set to be parallel to the extension direction of the earplug part, so that the direction of the current generated on the first metal branch can be changed from parallel to the second metal branch and the third metal branch. Converting the direction from the head to a direction perpendicular to the head can further increase the vertical electric field component between the headphone antenna and the head, thereby further exciting the surface waves radiated by the headphone antenna near the head, thereby improving the main Radiation performance of the antenna unit.

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

In a possible implementation manner of the first aspect, the sum of the length of the first radiator and the length of the second radiator is approximately half of the electromagnetic wave wavelength of the Bluetooth frequency band. Optionally, the sum of the lengths of the first radiator and the second radiator is approximately one-half of the electromagnetic wave wavelength of the WiFi frequency band.

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

In a possible implementation manner of the first aspect, the ear rod part includes a first shell and a second shell that are arranged oppositely, and the first shell and the second shell are detachably connected to form a receiving cavity for loading. In the internal structure of the wireless earphone, the first shell is located on a side of the ear rod part away from the earplug part, and the second shell is located on a side of the ear rod part close to the earplug part. The first radiating branch is fixed on the first shell, and the first metal branch is fixed on the second shell.

Description of drawings

In order to explain the technical solutions in the embodiments of the present application more clearly, the drawings required to be used in the embodiments of the present application will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a schematic diagram of a wireless earphone in a wearing state provided by 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 structural view of the wireless earphone shown in FIG. 2 .

FIG. 4 is a simplified structural schematic diagram of the earphone antenna of the wireless earphone shown in FIG. 2 .

FIG. 5 is a schematic diagram of the working principle of the main antenna unit of the earphone antenna shown in FIG. 4 .

FIG. 6 is a schematic diagram of the working principle of the earphone antenna shown in FIG. 4 .

FIG. 7 is a schematic diagram of the dimensions of an implementation of the earphone antenna shown in FIG. 4 .

FIG. 8 is a schematic diagram of the simulation curves of the reflection coefficient and transmission coefficient of the headphone antenna shown in FIG. 7 .

Figure 9 is a schematic diagram comparing the simulation results of the radiation efficiency of the traditional ear-rod TWS headphone antenna and the headphone antenna shown in Figure 7.

Figure 10 is a schematic diagram comparing the system efficiency simulation results of the traditional ear-rod TWS headphone antenna and the headphone antenna shown in Figure 7.

Figure 11 shows the traditional ear-bar type TWS headphone antenna and the ear-rod type shown in Figure 7 when both ears are wearing wireless headphones. Schematic diagram comparing the simulation results of the transmission coefficient of the aircraft antenna.

Figure 12 is a schematic diagram of the through-head gain simulation results of the headphone antenna shown in Figure 7.

Description of main component symbols

The following specific embodiments will further describe the present application in conjunction with the above-mentioned drawings.

Detailed ways

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. The drawings are only for illustrative purposes and represent only schematic diagrams, which should not be construed as limitations to the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

Explanation of terms

Vertical: The vertical defined in this application is not limited to the relationship of absolute vertical intersection (the included angle is 90 degrees). It is allowed that the influence of assembly tolerance, design tolerance, structural flatness and other factors are not absolute vertical intersection. The relationship allows deviations in a small angular range, for example, within the range of 80 degrees to 100 degrees, which can be understood as a vertical relationship.

Parallel: Parallel as defined in this application is not limited to absolute parallel. This definition of parallel can be understood as basic parallel, which allows for situations that are not absolutely parallel due to factors such as assembly tolerances, design tolerances, and structural flatness. These The situation may lead to two directions. For example, the extension direction of the second radiating branches and the extension direction of the earplug part are not absolutely parallel, but this application also defines this situation as being parallel.

Currently, wireless earphones, such as True Wireless Stereo (TWS) earphones, are rapidly gaining popularity due to their miniaturization and portability, and are deeply loved by the public. Wireless headsets can wirelessly connect to terminal devices such as mobile phones, laptops, tablets, and smart watches to be used in conjunction with the terminal devices, thereby processing media, calls and other audio services of the terminal devices. When in use, a wireless earphone system usually consists of two wireless earphones and a battery box, wherein the two wireless earphones can be used as left ear earphones and right ear earphones respectively, and the left ear earphone can be used in conjunction with the user's left ear. The right earphone can be used with the user's right ear. A receiving cavity is formed in the battery box to accommodate two wireless earphones and charge the two wireless earphones.

The ear-rod type TWS headset antenna currently on the market is generally designed on the back of the ear rod. Due to the extremely small size of TWS headphones and the impact of the complex electromagnetic environment near the human head, compared with the antenna on the terminal device, whether it is free There is a big gap between the space performance and the performance under the head mold. In order to overcome the influence of the extremely small size of the earphone antenna and the complex electromagnetic environment near the human head, ensure the performance stability of the earphone antenna, and improve the antenna efficiency of the earphone antenna as much as possible, the present application provides a wireless earphone. The earphone is an ear-bar type earphone, and the earphone antenna of the wireless earphone is an earphone antenna based on surface waves, supporting, for example, Bluetooth wireless communication or WiFi wireless communication.

Please refer to FIGS. 1 and 2 together. FIGS. 1 and 2 exemplarily illustrate a schematic diagram of a wireless earphone 100 provided by an embodiment of the present application in a wearing state and a schematic structural diagram thereof. The wireless earphone 100 may be a TWS earphone. The wireless earphone 100 includes a housing 10 , and the housing 10 includes an earplug part 11 and an ear rod part 12 connected to the ear plug part 11 . The extension direction of the ear rod part 12 is perpendicular to the ear plug part 11 . extension direction. In some embodiments, the ear rod part 12 may include a connecting part 1221 bent and extended from one end thereof, and the one end of the ear rod part 12 is connected to one end of the earplug part 11 through the connecting part 1221 connect. Specifically, as shown in FIG. 2 , the earplug part 11 includes an opposite first end 1101 and a second end 1102 , the ear rod part 12 includes an opposite first end 1201 and a second end 1202 , and the connecting part 1221 is bent and extended from the first end 1201 of the ear rod part 12, and then connected to the first end 1101 of the earplug part 11. The earplug part 11 extends in the direction from the first end 1101 to the second end 1102 , that is, extends in the direction YO shown in FIG. 2 . The ear rod portion 12 extends along the direction from the first end 1201 to the second end 1202 , that is, extends along the direction ZO shown in FIG. 2 . Wherein, the direction YO is perpendicular to the direction ZO.

Wherein, the earplug part 11 is used to be inserted into the user's ear. The earplug part 11 may also be called an ear bag part, and the ear rod part 12 may also be called an ear handle part. When the user wears the wireless earphone 100 , at least part of the structure of the earplug part 11 is embedded in the user's ear, and the ear rod part 12 is located outside the user's ear and is close to or in contact with the user's ear.

The ear rod part 12 includes a first housing 121 and a second housing 122 that are oppositely arranged. The first housing 121 and the second housing 122 are detachably connected to form a receiving cavity for loading the wireless earphone 100 . internal structure. Wherein, the first shell 121 is located on the side of the ear rod part 12 away from the earplug part 11 , and the second shell 122 is located on the side of the ear rod part 12 close to the earplug part 11 , that is, The connecting portion 1221 is bent and extended from one end of the second housing 122 . The first housing 121 and the second housing 122 may be connected together by, for example, buckling connection, threaded connection, etc., to facilitate later maintenance of the wireless earphone 100 .

Please refer to Figures 2 and 3 together. The wireless headset 100 also includes a main circuit board 21, a microphone 22, a battery 23, a speaker assembly 24 and other electronic components located in the housing 10, wherein the main The circuit board 21 can be disposed in the ear bar portion 12 , and the main circuit board 21 can be used to install electronic components such as main chips and touch components. The speaker assembly 24 is disposed in the earplug shell 111 of the earplug part 11 and is used to implement the audio playback function of the wireless earphone 100 . The battery 23 may be disposed in the earplug part 11 or the ear rod part 12 for powering other electronic components of the wireless earphone 100 . In this embodiment, the battery 23 is provided in the earplug part 11 .

It should be noted that FIG. 2 and FIG. 3 only schematically illustrate some structural components included in the wireless headset 100 , and the actual structure and position of these structural components are not limited by FIG. 2 and FIG. 3 , and relative to FIG. 2 and the structural components shown in FIG. 3 , the wireless earphone 100 may actually have more or fewer structural components. For example, the wireless earphone 100 may further include a pickup provided on the ear stem part 12 . Sound holes, dust-proof net components provided in the ear rod part 12, etc.

Please refer to FIGS. 3 and 4 together. The wireless earphone 100 further includes an earphone antenna 30 provided on/in the housing 10 . The earphone antenna 30 includes a main antenna unit 31 . The main antenna unit 31 is To realize the wireless communication function of the wireless headset 100. In this embodiment, the main antenna unit 31 includes a first radiator 311 and a feed structure 313 , wherein the feed structure 313 is electrically connected to one end of the first radiator 311 . Specifically, the first radiator 311 includes a first radiating branch 3111 disposed along the extending direction of the ear rod 12 , and the first radiating branch 3111 and the feed structure 313 are both disposed on the ear rod. On the part 12 , the feed structure 313 is electrically connected to one end of the first radiation branch 3111 .

In this embodiment, the first radiator 311 may further include a second radiation branch 3112 bent and extended from an end of the first radiation branch 3111 away from the feed structure 313. The second radiation branch 3112 is provided on the ear rod portion 12 . In this embodiment, the extending direction of the second radiating branch 3112 is perpendicular to the extending direction of the first radiating branch 3111 and the ear rod portion 12 , and the extending direction of the second radiating branch 3112 is parallel to the extending direction of the first radiating branch 3111 and the ear rod portion 12 . The extension direction of the earplug part 11.

Further, in this embodiment, the first radiator 311 further includes a third radiating branch 3113. The third radiating branch 3113 is provided on the earplug part 11 and is away from the second radiating branch 3112. One end of the first radiating branch 3111 is electrically connected. In this embodiment, the extension direction of the third radiating branch 3113 is parallel to the extension direction of the earplug portion 11 .

In other embodiments, the first radiator 311 may not include the third radiating branch 3113, or the first radiating body 311 may not include the second radiating branch 3112 and the third radiating branch 3113.

In this embodiment, the main antenna unit 31 also includes a second radiator 312 provided on the ear rod portion 12. The feed structure is also electrically connected to one end of the second radiator 312 . It can be understood that, in the case where the first radiator 311 includes the third radiating branch 3113, the feed structure 313 and the second radiator 312 are both disposed on the ear bar portion 12 away from the One end of the earplug part 11. In the case where the first radiator 311 does not include the third radiation branch 3113 , the feed structure 313 and the second radiator 312 may be disposed on the ear stem part 12 away from the earplug part 11 one end of the ear rod part 12 close to the earplug part 11 . Since the internal space of the ear bar portion 12 is limited, the second radiator 312 can be disposed along the extension direction of the ear bar portion 12 or along other directions. The arrangement of the second radiator 312 in this application is The direction is not limited.

The main antenna unit 31 also includes 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 feed structure 313 respectively.

In this embodiment, the structures of the first radiator 311, the second radiator 312, and the feed structure 313 configure the main antenna unit 31 into 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 a monopole. sub-antenna.

In this embodiment, the main antenna unit 31 adopts an FPC (Flexible Printed Circuit Board) antenna. Correspondingly, the wireless headset 100 also includes a first circuit board provided in the ear rod portion 12 25 and the second circuit board 26, and the third circuit board 27 provided in the earplug part 11, wherein the first circuit board 25, the second circuit board 26 and the third circuit board 27 are all It is a flexible circuit board, the first radiating branch 3111 and the second radiating branch 3112 can be provided on the first circuit board 25 , and the third radiating branch 3113 can be provided on the third circuit board 27 , the second radiator 312 may be disposed on the second circuit board 26 .

Specifically, in one embodiment, a first ground layer is formed on the first circuit board 25 , a second ground layer is formed on the second circuit board 26 , and a first ground layer is formed on the third circuit board 27 . A third ground layer, wherein the first ground layer can be used as the first radiating branch 3111 and the second radiating branch 3112, and the third ground layer can be used as the third radiating branch 3113, so The second ground layer may be used as the second radiator 312 . That is to say, the wireless earphone 100 directly uses the first ground layer of the first circuit board 25 located in the ear rod part 12 as the first radiation branch 3111 of the first radiator 311 of the main antenna unit 31 and the second radiating branch 3112, using the third ground layer of the third circuit board 27 located in the earbud part 11 as the third radiating branch 3113 of the first radiator 311 of the main antenna unit 31, using The second ground layer of the second circuit board 26 located in the ear rod portion 12 serves as the second radiator 312 of the main antenna unit 31 . In this way, there is no need to provide an additional bracket for carrying the first radiator 311 and the second radiator 312 , which prevents the bracket from occupying the limited internal space of the wireless earphone 100 , thus simplifying the structure of the wireless earphone 100 , and on the premise that the wireless earphone 100 can effectively transmit and receive signals, the device integration level of the wireless earphone 100 is improved, so that the structure of the wireless earphone 100 is more compact, thereby reducing the volume of the wireless earphone 100 .

It can be understood that the first circuit board 25 may also be provided with first power supply lines and first signal lines for chips, sensors, the microphone 22, etc., and the first ground layer is the first power supply line. and the first signal line provides a reference ground. The second circuit board 26 may also be provided with a second power supply line and a second signal line of a chip or the like, and the second ground layer provides a reference ground for the second power supply line and the second signal line. The third circuit board 27 may also be provided with a third power supply line and a third signal line of the battery 23, chip, sensor, speaker assembly 24, etc., and the third ground layer is the third power supply line. line and the third signal line provide a reference ground.

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, the second ground layer and the third The three ground layers can be isolated from the reference ground of the electronic components in the housing 10 of the wireless earphone 100 through isolation structures. The isolation structure may use 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, the second ground layer and the third ground layer may not be electrically connected to the ground layer of the main circuit board 21 . The relevant specific structure can adopt existing technology and will not be described again here.

In another embodiment, a first metal patch may be provided on the first circuit board 25 to form the first radiating branches 3111 and the second radiating branches 3112, and the second circuit board 26 may be provided with A second metal patch is provided to form the second radiator 312 , and a third metal patch can be provided on the third circuit board 27 to form the third radiation branch 3113 .

In other embodiments, the main antenna unit 31 may also be a ceramic antenna or a laser direct structuring (LDS antenna) antenna.

In this embodiment, the feed structure 313 includes a feed port (not shown), which is connected to one end of the first radiating branch 3111, one end of the second radiator 312, and The radio frequency module is electrically connected.

In order to ensure the integrity of the radiator of the main antenna unit 31, in some embodiments, the first radiating branch 3111 can be directly electrically connected to the second radiator 312, and the feed port can be provided on the The first radiating branch 3111 or the second radiating body 312 may be provided at the connection between the first radiating branch 3111 and the second radiating body 312 . Optionally, in some embodiments, the wireless headset 100 may further include a fourth circuit board (not shown) provided in the ear stem portion 12 , and a fourth ground circuit board is formed on the fourth circuit board. layer to form the third radiator of the main antenna unit 31, or a fourth metal patch is provided on the fourth circuit board to form the third radiator of the main antenna unit 31, wherein the third Three radiators are electrically connected between one end of the first radiating branch 3111 and one end of the second radiator 312 , and the feed port can be provided on the third radiator. This application does not specifically limit the connection method between the first radiating branch 3111 and the second radiating body 312 .

In one embodiment, the radio frequency module can be disposed on the second circuit board 26 , and the feed port can be connected to the second circuit board 26 through connecting elements such as metal spring pieces and metal connecting posts. The radio frequency module is electrically connected to realize the transmission of sending and receiving signals. Optionally, in another embodiment, the radio frequency module may be provided on the main circuit board 21 , and the feed structure 313 may further include a feed transmission line (not shown). The feed transmission line One end is electrically connected to the feed port, and the other end is electrically connected to the radio frequency module on the main circuit board 21 .

In this embodiment, the wireless headset 100 is a Bluetooth wireless headset supporting Bluetooth wireless communication. Correspondingly, in the embodiment in which the main antenna unit 31 includes the second radiator 312, the first radiator 311. The structure of the second radiator 312 and the feed structure 313 configures the main antenna unit 31 into a folded dipole antenna. The length of the first radiator 311 is the same as that of the second radiator. The sum of the lengths of the main antenna unit 312 is approximately half of the electromagnetic wave wavelength of the Bluetooth frequency band; in the embodiment in which the main antenna unit 31 does not include the second radiator 312, the first radiator 311 and the The structure of the feed structure 313 constructs the main antenna unit 31 as a monopole antenna, and the length of the first radiator 311 is approximately one quarter of the electromagnetic wave wavelength of the Bluetooth band.

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

It should be noted that “approximately” means 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 band or WiFi band, that is, the length of the main antenna unit 31 The difference between the length of the radiator 31 and one-half or one-fourth of the electromagnetic wave wavelength of the Bluetooth band or WiFi band is within a preset range. During specific implementation, the main unit can be adjusted by adjusting the matching circuit, etc. The electrical length of the radiator of the antenna unit 31 is equal to one-half or one-quarter of the electromagnetic wave wavelength of the Bluetooth band or WiFi band, but the physical length of the radiator of the main antenna unit 31 is not necessarily exactly equal to the Bluetooth band or WiFi band. The frequency band is one-half or one-quarter of the wavelength of electromagnetic waves.

In this embodiment, the headphone antenna 30 further includes a resonant unit 32 provided on the ear bar portion 12 , and the resonant unit 32 includes a first metal branch 321 disposed along the extension direction of the ear bar portion 12 . . Wherein, the first radiating branch 3111 is arranged opposite to the first metal branch 321, and the first radiating branch 3111 is located on a side of the ear stem part 12 away from the earplug part 11, and the first metal The branches 321 are located on the side of the ear rod portion 12 close to the earplug portion 11 .

In one implementation, the first radiating branch 3111 is fixed on the first housing 121 , and the first metal branch 321 is fixed on the second housing 122 . Specifically, the first housing 121 can be used as a bracket for the first circuit board 25 to fix the first circuit board 25, thereby fixing the first radiating branch 3111 to the first housing 121, The first radiating branch 3111 is located on the side of the ear rod portion 12 away from the earplug portion 11 . The second shell 122 can be used as a bracket for the first metal branch 321 to fix the first metal branch 321 so that the first metal branch 321 is located on the ear stem portion 12 close to the earplug portion 11 one side. The first metal branch 321 may be provided on the inside or outside of the second housing 122 or as a part of the structure of the second housing 122, which is not limited in this application.

In this embodiment, the resonant unit 32 is used for 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 working frequency band of the main antenna unit 31 , and the sum of the lengths of the metal branches contained in the resonant unit 32 is the electromagnetic wave wavelength of the target resonant frequency band. Half.

Due to the extremely small size of the ear rod portion 12 , the length of the first metal branch 321 may not be half the electromagnetic wave wavelength of the target resonance frequency band. In order to extend the electrical length of the first metal branch 321 so that the resonant unit 32 resonates in the target resonance frequency band, the resonant unit 32 may also include a bend extending from at least one end of the first metal branch 321 The metal segment and the first metal branch 321 jointly cause the resonant unit 32 to resonate in the target resonant frequency band, thereby enabling the resonant unit 32 to generate electric field coupling with the main antenna unit 31 .

In this embodiment, the metal segment includes a second metal branch 322 bent and extended from an end of the first metal branch 321 away from the earplug part 11 and the connecting part 1221 and a second metal branch 322 extending from the first metal branch 321 . The branch 321 is close to the earplug part 11 and the third metal branch 323 bent and extended from one end of the connecting part 1221 .

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

In other embodiments, if the length of the first metal branch 321 can be half of the electromagnetic wave wavelength of the target resonance frequency band, the resonant unit 32 may not be provided with the second metal branch 322 and The third metal Branch 323.

The working principle of the headphone antenna 30 will be introduced below with reference to FIG. 5 and FIG. 6 .

Referring to FIG. 5 , when the main antenna unit 31 feeds electricity and radiates electromagnetic waves, radiation current is generated on both the first radiator 311 and the second radiator 312 . The radiation current is transmitted along the extending direction of the first radiator 311 and the second radiator 312 . When the wireless earphone 100 is in the wearing state, since at least part of the structure of the earplug part 11 is embedded in the user's ear, the ear rod part 12 is located outside the user's ear and is close to or in contact with the user's ear. Therefore, the ear bar portion 12 is substantially parallel to the human head. Therefore, the current direction on the second radiating branch 3112 and the third radiating branch 3113 is perpendicular to the human head, while the current direction on the first radiating branch 3111 is parallel to the human head. Correspondingly, the direction of the electric field generated by the second radiating branch 3112 and the third radiating branch 3113 is mainly perpendicular to the human head, while the direction of 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 the interface 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 mainly appears as a parallel component at the interface between the air and the human head, the attenuation will be large; if the electric field component mainly appears as a vertical component , the attenuation is smaller. When electromagnetic waves appear as surface waves at the interface between air and the human head, the parallel electric field component is easily absorbed by the head/human body, while the vertical electric field component is not easily absorbed by the human body, and the increase in the vertical electric field component can significantly optimize the radiation performance of the antenna. It should be noted that the "perpendicular component" or "vertical electric field component" mentioned in this application refers to the electric field component perpendicular to the head/human body, and the "parallel component" or "parallel electric field component" mentioned in this application refers to Component of the electric field parallel to the head/body.

In this embodiment, the wireless earphone 100 disposes the first radiating branch 3111 of the first radiator 311 in the ear bar portion 12 along the extending direction of the ear bar portion 12 , along a direction parallel to the ear bar portion 12 . The second radiating branch 3112 of the first radiator 311 is provided in the extending direction of the earplug part 11 , and the first radiating branch 3111 is provided on the side of the ear stem part 12 away from the earplug part 11 , so that it is possible to The length of the second radiating branch 3112 is increased and the length of the first radiating branch 3111 is shortened; at the same time, the wireless earphone 100 also provides the third radiating branch 3113 in the earbud part 11, so that further Shorten the length of the first radiating branch 3111. Since the extension directions of the second radiating branches 3112 and the third radiating branches 3113 are parallel to the extending direction of the earplug part 11 and perpendicular to the extension of the first radiating branches 3111 and the ear rod part 12 direction, that is, perpendicular to the human head, so that the length of the first radiating branch 3111 can be shortened by increasing the second radiating branch 3112 and the third radiating branch 3113, thereby extending the radiation current of the main antenna unit 31 The purpose of the vertical current path is to increase the vertical electric field component of the electromagnetic wave radiated by the main antenna unit 31, and to shorten the parallel current path of the radiation current to reduce the parallel electric field component that can be absorbed by the human body, thereby being able to excite more of the The earphone antenna 30 radiates surface waves near the human head to improve the radiation performance of the main antenna unit 31 .

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

Referring to FIG. 6 , the wireless earphone 100 adds a resonant unit 32 to the main antenna unit 31 and installs an edge parallel to the ear stem 12 on the side of the ear stem 12 close to the earplug 11 . The first metal branch 321 of the resonant unit 32 is arranged in the extension direction, and is blocked between the first radiation branch 3111 and the human head by the first metal branch 321, so that the main antenna unit 31 and the resonant unit 32 generates electric field coupling, thereby enabling the first A vertical electric field perpendicular to the ear rod portion 12 and the human head is generated between the radiating branch 3111 and the human head, thereby achieving the purpose of converting the parallel electric field component generated by the first radiating branch 3111 into a vertical electric field component, thereby reducing the amount of energy that can be absorbed by the human body. The parallel electric field component and the increased vertical electric field component that are difficult to be absorbed by the human body can further stimulate the surface waves radiated by the headphone antenna 30 near the human head, and further improve the radiation performance of the main antenna unit 31, ultimately achieving The goal is to optimize the user experience and quality of using the wireless headset 100 .

Further, the wireless earphone 100 is configured by arranging bent and extended metal sections (the second metal section 322 and the third metal section 323) at both ends of the first metal section 321 of the resonant unit 32, and connecting the third section to the metal section. The extension directions of the two metal branches 322 and the third metal branches 323 are both set to be parallel to the extension direction of the earplug part 11 . In addition, all the extension directions of the second metal branches 322 and the third metal branches 323 can be extended. In addition to the electrical length of the first metal branch 321, as shown in Figure 6, the second metal branch 322 and the third metal branch 323 can also change the direction of the current generated on the first metal branch 321 from The direction parallel to the person's head is converted into a direction perpendicular to the person's head, thereby further increasing the vertical electric field component of the headphone antenna 30 and further exciting the surface waves radiated by the headphone antenna 30 near the person's head to improve the main Radiation performance of antenna unit 31.

From the above, it can be seen that the earphone antenna 30 provided in this application is essentially a TWS earphone antenna based on surface waves.

Taking the headphone antenna 30 of the wireless headset 100 operating in the Bluetooth frequency band as an example below, a simulation analysis is performed on the antenna performance parameters such as antenna efficiency, through-head gain, and transmission coefficient S21 of the headphone antenna 30 of the wireless headset 100 .

Please refer to Figures 6 and 7 together. In one embodiment, the length L1 of the first radiating branch 3111 is set to 25mm, the length L2 of the second radiating branch 3112 is set to 6.4mm, and the length L2 of the third radiating branch 3111 is set to 6.4mm. The length L3 of the radiating branch 3113 is set to 10 mm, the length L4 of the second radiator 312 is 1 to 10 mm, the length L5 of the first metal branch 321 is set to 30 mm, the second metal branch 322 and the third metal branch are The length L6 of the three metal branches 323 is set to 3 mm. The feed port adopts discrete port mode for feeding, and the input impedance is designed to be 50 ohms. It should be noted that the above size parameters or matching parameters are only the design parameters of an embodiment of an ultra-small TWS headphone antenna operating in the Bluetooth band. The design of the headphone antenna 30 is not limited to the above size parameters or matching parameters. Those skilled in the art can modify or adjust the size parameters or matching component parameters according to actual design requirements. For example, those skilled in the art can modify the size parameters or matching component parameters to design headphone antennas for wireless headsets that support other wireless communication methods. All technical modifications made based on the technical solutions of this application are covered by the protection scope of this application.

8 to 11 are schematic diagrams of the antenna performance parameter simulation after matching of the headphone antenna 30 designed with the size parameters shown in FIG. 7 .

Please refer to FIG. 8 , which is a schematic diagram of a simulation curve of the reflection coefficient S11 and the transmission coefficient S21 (also called coupling coefficient) of the earphone antenna 30 shown in FIG. 7 . It can be seen from Figure 8 that after matching, the headphone antenna 30 designed with the size shown in Figure 7 has a -6dB impedance bandwidth of 2418-2483GHz, which basically covers the Bluetooth frequency band. It can be seen from the curve of the reflection coefficient S11 that the center frequency point where the headphone antenna 30 works is 2450MHz. When both ears of a human body wear wireless headphones, the transmission coefficient S21 of the headphone antenna 30 at the center frequency point of 2450 MHz is -48.4dB, which can meet the design requirements of the headphone antenna 30 .

Please refer to FIG. 9 , which is a schematic diagram comparing the simulation results of the radiation efficiency of the traditional ear-rod TWS headphone antenna and the headphone antenna 30 shown in FIG. 7 . Among them, the traditional ear-rod type TWS headphone antenna has the feed structure 313 provided at an end of the ear rod portion 12 away from the earplug portion 11 , and the first radiating branch 3111 is provided at the ear rod portion 12 close to the end of the ear rod portion 12 . On one side of the earplug part 11 , the second radiating branch 3112 and the resonant unit 32 are not provided, and the third radiating branch 3113 It is electrically connected to one end of the first radiation branch 3111 away from the feed structure 313 .

As can be seen from Figure 9, the radiation efficiency of the traditional ear-rod TWS headphone antenna at the center frequency of 2450MHz is -9.3dB. After matching, the headphone antenna 30 designed with the size shown in Figure 7 has a radiation efficiency of -6.4dB at the center frequency point of 2450MHz, which is compared with the traditional design of the ear-rod TWS headphone antenna. Radiation efficiency, the radiation efficiency of the headphone antenna 30 is increased by about 3dB. It can be seen that the radiation efficiency of the headphone antenna 30 is significantly improved.

Please refer to FIG. 10 , which is a schematic diagram comparing the system efficiency simulation results of the traditional ear-rod TWS headphone antenna and the headphone antenna 30 shown in FIG. 7 . As can be seen from Figure 10, the average system efficiency of the traditional design ear-rod TWS headphone antenna within the Bluetooth frequency band bandwidth is -9.3dB. After matching, the headphone antenna 30 designed with the size shown in Figure 7 has an average system efficiency of about -7dB within the Bluetooth frequency band bandwidth. Compared with the traditional design of the ear-rod TWS headphone antenna, System efficiency, the system efficiency of the headphone antenna 30 has been improved by about 2.5dB. It can be seen that the system efficiency of the headphone antenna 30 has been significantly improved.

Please refer to Figure 11. Figure 11 is a schematic diagram comparing the transmission coefficient simulation results of the traditional ear-rod TWS headphone antenna and the headphone antenna 30 shown in Figure 7 when both ears are wearing wireless headphones. As can be seen from Figure 10, the transmission coefficient S21 of the traditional ear-rod TWS headphone antenna at the center frequency point of 2450MHz is -62.6dB. After matching, the headphone antenna 30 designed with the size shown in Figure 7 has a transmission coefficient S21 of -48.4dB at the center frequency point of 2450MHz. Compared with the ear-rod TWS headphone antenna of the traditional design, The transmission coefficient is improved by about 14dB, which can meet the design requirements of the headphone antenna 30 .

Please refer to FIG. 12 , which is a schematic diagram of the through-head gain simulation results of the headphone antenna 30 shown in FIG. 7 . As can be seen from Figure 12, the minimum gain value of the headset near the non-wearing ear reaches -22.5dBi, which is greater than the industry reference value of -30dBi. The maximum SAR (Specific Absorption Rate, absorption ratio) value of the human head is calculated through simulation software to be 0.48W/Kg@1g, which is less than the industry reference value of 1.1W/Kg@1g, which means the SAR value of the headphone antenna 30 is reduced. It can be seen that, Compared with the ear-rod type TWS earphone antenna of traditional design, the earphone antenna 30 shown in FIG. 7 also has a greater improvement in head-through gain and can meet the design requirements of the earphone antenna 30 .

In summary, it can be seen from the above analysis that compared with the earphone antenna of the ear-bar type TWS earphone of the traditional design, the earphone antenna 30 of the wireless earphone 100 provided by the present application is passed between the earplug part 11 and the ear-rod part 12 The third radiating branch 3113 and the second radiating branch 3112 are arranged parallel to the extension direction of the earplug part 11 , and the first radiating branch 3111 of the main antenna unit 31 and the human head are added. The resonant unit 32 greatly improves the antenna performance of the headphone antenna 30 such as antenna efficiency, penetration gain, transmission coefficient S21, etc., thereby significantly optimizing the antenna performance of the wireless headset 100 and improving the wireless The safety of the use of the earphone 100 can ensure that the wireless earphone 100 has good connection performance, so as to improve the communication performance between the wireless earphone 100 and the terminal device, and improve the communication performance between the two wireless earphones 100, It can bring better user experience to users.

The above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application. All are covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

A wireless headset including:

A housing including an earplug part and an ear rod part connected to the earplug part; and

Headphone antenna, including:

The main antenna unit includes a first radiator and a feed structure; the first radiator includes a first radiating branch arranged along the extension direction of the ear rod portion; the first radiating branch and the feeding structure both Provided on the ear rod part, the feed structure is electrically connected to one end of the first radiating branch; and

A resonant unit is provided on the ear rod part, the resonant unit includes a first metal branch arranged along the extension direction of the ear rod part; the first radiating branch is arranged opposite to the first metal branch, and The first radiating branch is located on a side of the ear rod part away from the earplug part, and the first metal branch is located on a side of the ear rod part close to the earplug part;

Wherein, the resonant unit is used for electric field coupling with the main antenna unit.
The wireless earphone according to claim 1, wherein the first radiator further includes a second radiation branch bent and extended from an end of the first radiation branch away from the feed structure, and the Two radiating branches are arranged on the ear rod part.
The wireless earphone according to claim 2, wherein the earplug part includes an opposite first end and a second end, the ear rod part includes an opposite first end and a second end, and the ear rod part The first end is connected to the first end of the earplug part;

The earplug part extends in a direction from the first end of the earplug part to the second end of the earplug part, and the ear rod part extends along the direction from the first end of the ear rod part to the second end of the ear rod part. The extension direction of the ear rod part is perpendicular to the extension direction of the earplug part, and the extension direction of the second radiating branch is parallel to the extension direction of the earplug part.
The wireless earphone according to claim 3, wherein the power feeding structure is provided at an end of the ear rod part away from the earplug part;

The first radiator further includes a third radiating branch, the third radiating branch is provided on the earplug part and is electrically connected to an end of the second radiating branch away from the first radiating branch; the third radiating branch is The extension direction of the radiating branches is parallel to the extension direction of the earplug part.
The wireless earphone according to any one of claims 1 to 4, characterized in that the main antenna unit further includes a second radiator provided on the ear rod part, and the feed structure is also connected to the third One end of the two radiators is electrically connected.
The wireless earphone according to claim 1, wherein 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 jointly The resonant unit is made to resonate in a target resonant frequency band, so that the resonant unit can perform electric field coupling with the main antenna unit.
The wireless earphone according to claim 6, wherein the earplug part includes an opposite first end and a second end, the ear rod part includes an opposite first end and a second end, and the ear rod part The first end is connected to the first end of the earplug part;

The earplug part extends in a direction from the first end of the earplug part to the second end of the earplug part, and the ear rod part extends along the direction from the first end of the ear rod part to the second end of the ear rod part. The extension direction of the ear rod part is perpendicular to the extension direction of the earplug part; the extension direction of the metal section is parallel to the extension direction of the earplug part.
The wireless earphone according to claim 7, wherein the metal section includes a second metal section bent and extended from an end of the first metal section away from the earbud part, and a second metal section extending from the first metal section. A third metal branch is bent and extended from one end close to the earplug part.
The wireless headset according to any one of claims 1 to 4, wherein the length of the first radiator is approximately one quarter of the electromagnetic wave wavelength of the Bluetooth frequency band; or

The length of the first radiator is approximately one quarter of the electromagnetic wave wavelength of the WiFi frequency band.
The wireless earphone according to claim 5, wherein the sum of the length of the first radiator and the length of the second radiator is approximately half of the electromagnetic wave wavelength of the Bluetooth frequency band; or

The sum of the lengths of the first radiator and the second radiator is approximately half the wavelength of electromagnetic waves in the WiFi frequency band.
The wireless earphone according to claim 8, wherein the sum of the lengths of the metal branches included in the resonant unit is half of the electromagnetic wave wavelength of the target resonant frequency band.
The wireless earphone according to claim 1, characterized in that the ear rod part includes a first shell and a second shell arranged oppositely, and the first shell and the second shell are detachably connected to surround the receiving body. The cavity is used to load the internal structure of the wireless earphone, wherein the first shell is located on a side of the ear stem part away from the earplug part, and the second shell is located on a side of the ear stem part close to the earplug part. one side;

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