Patent Publication Number: US-2023137605-A1

Title: Wireless earset

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the priority benefit of Chinese Patent Application Serial Number 202122634358.8, filed on Oct. 29, 2021, the full disclosure of which is incorporated herein by reference. 
     BACKGROUND 
     Technical Field 
     The present disclosure relates to the technical field of communication technology, and in particular to a wireless earset or headset. 
     Related Art 
     As Bluetooth headsets and earsets become more popular in the market, people&#39;s requirements for the appearance design and the function of the Bluetooth headset and earsets becomes higher. In terms of appearance design, the volume must be small enough to be easy to wear. However, the more multi-functional requirements, the more electronic components need to be added, so that the space where the antenna can be installed is squeezed, which limits the design of the antenna, resulting in poor over-the-air (OTA) performance of the antenna and poor radiation pattern of the antenna, which causes a problem of poor user experience. 
     In addition, with the increasing number of electronic products, such as routers, bracelets, sports watches, and cameras, that work on the 2.4G frequency band, the 2.4G frequency band has become overcrowded. Therefore, the requirements for the anti-interference ability of Bluetooth headset and earsets need to be raised accordingly to avoid affecting the user experience. 
     SUMMARY 
     The present disclosure provides a wireless earset, which can effectively solve the problems that the OTA performance and pattern of the antenna existing in the Bluetooth earset are poor and the anti-interference ability needs to be improved. 
     In order to solve the above technical problem, the present disclosure is implemented as follows. 
     The present disclosure provides a wireless earset, which includes a housing, a first antenna, a second antenna, a switching circuit, and a control circuit. The first antenna is disposed in a first position in the housing, and the second antenna is disposed in a second position in the housing. There is an interval between the first position and the second position, and the first antenna and the second antenna are configured to generate different radiation patterns. The switching circuit is disposed in the housing and selectively electrically connected to the first antenna or the second antenna. The control circuit is disposed in the housing and electrically connected to the switching circuit, the first antenna, and the second antenna. The control circuit is configured to output a first radio frequency signal and control the switching circuit to switch alternatively to electrically connect the first antenna and the second antenna, so that the first antenna and the second antenna transmit the first radio frequency signal at different times. The control circuit is configured to obtain and determine a received signal strength of the first antenna and the second antenna after the switching circuit electrically connects the first antenna and the second antenna respectively, and control the switching circuit to electrically connect the first antenna or the second antenna, which has a greater received signal strength, to receive a second radio frequency signal. 
     In the embodiment of the present disclosure, the design of the first antenna and the second antenna that are set in different positions and have different radiation patterns (i.e., the dual antenna design) can solve the problem that the OTA performance and pattern of the antenna existing in the Bluetooth earset are poor. In addition, through the dual antenna design and the procedure of switching alternatively between the first antenna and the second antenna with the switching circuit (that is, the dual-antenna switching technology is adopted), the transmission or reception of radio frequency signals can be realized, the influence of in-band and out-of-band interference in the external environment on the antenna performance can be reduced, and the anti-interference ability is improved, thereby enhancing the user experience. 
     It should be understood, however, that this summary may not contain all aspects and embodiments of the present disclosure, that this summary is not meant to be limiting or restrictive in any manner, and that the disclosure as disclosed herein will be understood by one of ordinary skill in the art to encompass obvious improvements and modifications thereto. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features of the exemplary embodiments believed to be novel and the elements and/or the steps characteristic of the exemplary embodiments are set forth with particularity in the appended claims. The Figures are for illustration purposes only and are not drawn to scale. The exemplary embodiments, both as to organization and method of operation, may best be understood by reference to the detailed description which follows taken in conjunction with the accompanying drawings in which: 
         FIG.  1    is a schematic structural diagram of a wireless earset according to an embodiment of the present disclosure. 
         FIG.  2    is a block diagram of a wireless earset according to an embodiment of the present disclosure. 
         FIG.  3    is a horizontal radiation pattern of an embodiment of the first antenna of  FIG.  1   . 
         FIG.  4    is a horizontal radiation pattern of an embodiment of the second antenna of  FIG.  1   . 
         FIG.  5    is a schematic circuit diagram of a wireless earset according to a first embodiment of the present disclosure. 
         FIG.  6    is a schematic circuit diagram of a wireless earset according to a second embodiment of the present disclosure. 
         FIG.  7    is a schematic circuit diagram of a wireless earset according to a third embodiment of the present disclosure. 
         FIG.  8    is a schematic circuit diagram of a wireless earset according to a fourth embodiment of the present disclosure. 
         FIG.  9    is a block diagram of a wireless earset according to another embodiment of the present disclosure. 
         FIG.  10    is a block diagram of a wireless earset according to another embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the disclosure are shown. This present disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art. 
     Certain terms are used throughout the description and following claims to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This document does not intend to distinguish between components that differ in name but function. In the following description and in the claims, the terms “include/including” and “comprise/comprising” are used in an open-ended fashion, and thus should be interpreted as “including but not limited to”. 
     The following description is of the best-contemplated mode of carrying out the disclosure. This description is made for the purpose of illustration of the general principles of the disclosure and should not be taken in a limiting sense. The scope of the disclosure is best determined by reference to the appended claims. 
     Moreover, the terms “include”, “contain”, and any variation thereof are intended to cover a non-exclusive inclusion. Therefore, a process, method, object, or device that includes a series of elements not only includes these elements, but also includes other elements not specified expressly, or may include inherent elements of the process, method, object, or device. If no more limitations are made, an element limited by “include a/an . . . ” does not exclude other same elements existing in the process, the method, the article, or the device which includes the element. 
     It must be understood that when a component is described as being “connected” or “coupled” to (or with) another component, it may be directly connected or coupled to other components or through an intermediate component. In contrast, when a component is described as being “directly connected” or “directly coupled” to (or with) another component, there are no intermediate components. In addition, unless specifically stated in the specification, any term in the singular case also comprises the meaning of the plural case. 
     In the following embodiment, the same reference numerals are used to refer to the same or similar elements throughout the disclosure. 
     Please refer to  FIGS.  1  and  2   , wherein  FIG.  1    is a schematic structural diagram of a wireless earset according to an embodiment of the present disclosure, and  FIG.  2    is a block diagram of a wireless earset according to an embodiment of the present disclosure. As shown in  FIGS.  1  and  2   , in this embodiment, the wireless earset  100  comprises a housing  110 , a first antenna  120 , a second antenna  130 , a switching circuit  140 , and a control circuit  150 . The first antenna  120 , the second antenna  130 , the switching circuit  140  and the control circuit  150  are disposed in the housing  110 , the switching circuit  140  is selectively electrically connected to the first antenna  120  or the second antenna  130 , and the control circuit  150  is electrically connected to the switching circuit  140 , the first antenna  120  and the second antenna  130 . 
     In actual implementation, the wireless earset  100  may be, but not limited to, a true wireless stereo (TWS) earset or a TWS headset; each of the first antenna  120  and the second antenna  130  may be, but not limited to, a monopole antenna, an inverted F-shaped antenna (IFA), a ceramic antenna, a printed circuit board (PCB) antenna, a flexible printed circuit (FPC) antenna, a steel-sheet antenna or a laser direct structuring (LDS) antenna; each of the switching circuit  140  and the control circuit  150  can be, but are not limited to, an analog circuit, an integrated circuit (IC), a digital circuit or other devices to achieve their functions, wherein the integrated circuit can be, for example, a microprocessor, a microcontroller (MCU), a programmable logic gate array (e.g., FPGA and CPLD) or an application specified integrated circuit (ASIC), the analog circuit may include multiple electronic components, and the electronic components are the components required by the TWS earset or the TWS headset. 
     In this embodiment, the first antenna  120  is disposed in a first position in the housing  110 , the second antenna  130  is disposed in a second position in the housing  110 , and there is an interval between the first position and the second position. The first antenna  120  and the second antenna  130  are configured to generate different radiation patterns. 
     In an example, the wireless earset  100  may be an earphone with a long handle, and the housing  110  may comprise an ear plug portion  60  and an ear handle portion  70 . The first position is located on one side of the ear handle portion  70  close to the ear plug portion  60 . The second position is located on one side of the ear handle portion  70  away from the ear plug portion  60 , as shown in  FIG.  1   . By the interval between the first position and the second position, the isolation between the first antenna  120  and the second antenna  130  is increased. 
     In an example, please refer to  FIGS.  3  and  4   , wherein  FIG.  3    is a horizontal radiation pattern of an embodiment of the first antenna of  FIG.  1   , and  FIG.  4    is a horizontal radiation pattern of an embodiment of the second antenna of  FIG.  1   . Specifically,  FIG.  3    is a horizontal radiation pattern of the total radiated power (TRP) of the 39th channel of the first antenna  120 , and  FIG.  4    is a horizontal radiation pattern of the TRP of the 39th channel of the second antenna  130 . It can be seen from  FIG.  3    that the radiation of the first antenna  120  in the 150-degree area is relatively weak, where the signal strength is about —10 dB, which is the signal blind area of the first antenna  120 . It can be seen from  FIG.  4    that the signal strength of the second antenna  130  in the 150-degree area is about −1 dB. Therefore, the signal strength of the second antenna  130  in the 150-degree area can complement with that of the signal blind area of the first antenna  120 . Similarly, the signal strength of the first antenna  120  in the 30-degree area can complement with that of the signal blind area of the second antenna  130 . It can be seen that  FIGS.  3  and  4    can be combined to obtain a relatively complete radiation pattern (that is, the radiation pattern provided by the first antenna  120  and the radiation pattern provided by the second antenna  130  are complementary), which can enhance the anti-interference ability of the wireless earset  100  and is the advantage that the traditional Bluetooth earset with only a single antenna does not have. It should be noted that the appearance of the actual wireless earset  100  (that is, the shape of the housing  110 ) and the radiation patterns and configuration positions of the first antenna  120  and the second antenna  130  can be adjusted according to actual needs, and the radiation patterns provided by the first antenna  120  and the second antenna  130  can be adjusted according to the shapes or antenna types of the first antenna  120  and the second antenna  130 . 
     In this embodiment, the control circuit  150  is configured to output the first radio frequency signal, and controls the switching circuit  140  to switch alternatively to electrically connect the first antenna  120  and the second antenna  130 , so that the first antenna  120  and the second antenna  130  transmit the first radio frequency signal at different times. In more detail, when the wireless earset  100  needs to transmit the first radio frequency signal to an external electronic device, the wireless earset  100  can output the first radio frequency signal through the control circuit  150 , and cooperate with the switching circuit  140  to switch alternatively to electrically connect the first antenna  120  and the second antenna  130  within nanoseconds, so that the first antenna  120  and the second antenna  130  transmit the first radio frequency signal at different times, and the radiation patterns provided by the first antenna  120  and the second antenna  130  are complementary. Therefore, the omni-directional transmission of the first radio frequency signal can be improved, the signal blind area of the wireless earset  100  can be reduced, and the communication quality between the wireless earset  100  and the external electronic device can be improved. The first radio frequency signal output by the control circuit  150  may include, but is not limited to, the user&#39;s voice signal received by the microphone not drawn of the wireless earset  100 . 
     In this embodiment, the control circuit  150  is configured to obtain and determine a received signal strength (e.g., received signal strength indicator, RSSI) of received signals of the first antenna  120  and the second antenna  130  after the switching circuit  140  electrically connects the first antenna  120  and the second antenna  130  respectively, and control the switching circuit  140  to electrically connect the first antenna  120  or the second antenna  130  with a greater received signal strength (e.g., greater RSSI) to receive a second radio frequency signal. In more detail, the greater RSSI of the antenna, the closer the distance between the antenna and the external electronic device; therefore, when the wireless earset  100  needs to receive the second radio frequency signal from the external electronic device, it can determine the distance between the first antenna  120  and the external electronic device according to the RSSI of the first antenna  120 , and the distance between the second antenna  130  and the external electronic device according to the RSSI of the second antenna  130 , and can receive the second radio frequency signal by electrically connecting the switching circuit  140  to the antenna with a greater RSSI (for example, the first antenna  120  or the second antenna  130 ), thereby improving the communication quality between the wireless earset  100  and the external electronic device. It should be noted that the switching time for the switching circuit  140  to be electrically connected to the first antenna  120  and the second antenna  130  may be, but not limited to, in nanoseconds. The second radio frequency signal received by the control circuit  150  may include, but is not limited to, an audio signal from the external electronic device, and the control circuit  150  may transmit the received second radio frequency signal to the speaker not shown of the wireless earset  100  to play. 
     In an embodiment, the wireless earset  100  may further comprise a main board  90  disposed in the housing  110 . The control circuit  150 , the switching circuit  140 , the first antenna  120  and the second antenna  130  are disposed on the main board  90 . The control circuit  150  is disposed on one surface of the main board  90 , and the switching circuit  140 , the first antenna  120  and the second antenna  130  are disposed on another surface of the main board  90 . The main board  90  may be, but is not limited to, a printed circuit board. Therefore, the connection lines between the control circuit  150  and the switching circuit  140 , the connection lines between the switching circuit  140  and the first antenna  120 , the connection lines between the switching circuit  140  and the second antenna  130 , the connection lines between the control circuit  150  and the first antenna  120 , and the connection lines between the control circuit  150  and the second antenna  130  can be hidden in the wiring configuration of the main board  90 . 
     In an embodiment, referring to  FIGS.  1  and  2   , the first antenna  120  may be provided with a first feeding point  122  electrically connected to the switching circuit  140 , and the first feeding point  122  is configured to feed the first radio frequency signal. The second antenna  130  may be provided with a second feeding point  132 , which is electrically connected to the switching circuit  140 , and the second feeding point  132  is configured to feed the first radio frequency signal. 
     In an embodiment, the area of the ground plate can affect the gain value applied to the radio frequency signal transmission and reception. Since the space in which the first antenna  120  and the second antenna  130  can be installed in the wireless earset  100  is limited, the design of the ground plane of the first antenna  120  and the second antenna  130  may be limited, so that there is a problem that the first antenna  120  and the second antenna  130  cannot have better performance due to the gain values applied to the radio frequency signal transmission and reception. Therefore, the gain values applied to the radio frequency signal transmission and reception of the first antenna  120  and the second antenna  130  can be increased by means of parasitic coupling, and the bandwidths of the first antenna  120  and the second antenna  130  can be increased. The realization method can be put into practice by using the control circuit  150  to control the switching circuit  140  to electrically connect the first antenna  120  and ground the second antenna  130 ; or using the control circuit  150  to control the switching circuit  140  to electrically connect the second antenna  130  and ground the first antenna  120 . In more detail, since the first antenna  120  and the second antenna  130  can not work at the same time, the control circuit  150  can control the switching circuit  140  to ground the antenna not working (i.e., the first antenna  120  or the second antenna  130 ), so that the area of the ground plate of the working antenna can be increased, and the radiation efficiency of the working antenna can be improved. 
     In one embodiment, please refer to  FIG.  5   , which is a schematic circuit diagram of a wireless earset according to a first embodiment of the present disclosure. As shown in  FIG.  5   , the switching circuit  140  may comprise a single-pole double-throw switch  141 . The single-pole double-throw switch  141  comprises a first terminal  51 , a second terminal  52 , and a third terminal  53 , the first terminal  51  is connected to the third terminal  53  or the second terminal  52  is connected to the third terminal  53 , the third terminal  53  is electrically connected to the control circuit  150 , the first terminal  51  is electrically connected to the first antenna  120 , and the second terminal  52  is electrically connected to the second antenna  130 . 
     In another embodiment, please refer to  FIG.  6   , which is a schematic circuit diagram of a wireless earset according to a second embodiment of the present disclosure. As shown in  FIG.  6   , in addition to the single-pole double-throw switch  141 , the switching circuit  140  may further comprise a first switch  142  and a second switch  143 . The first terminal  51  is further electrically connected to one end of the first switch  142 , and the second terminal  52  is further electrically connected to one end of the second switch  143 , and the other end of the first switch  142  and the other end of the second switch  143  are grounded. In order to realize that the control circuit  150  is configured to control the switching circuit  140  to ground the second antenna  130  when controlling the switching circuit  140  to be electrically connected to the first antenna  120 , the control circuit  150  turns on and grounds the second switch  143 , and turns off the first switch  142  when it controls the first terminal  51  to connect the third terminal  53 . In order to realize that the control circuit  150  is configured to control the switching circuit  140  to ground the first antenna  120  when controlling the switching circuit  140  to be electrically connected to the second antenna  130 , the control circuit  150  turns off the second switch  143 , and turns on and grounds the first switch  142  when it controls the second terminal  52  to connect the third terminal  53 . 
     In one embodiment, please refer to  FIG.  7   , which is a schematic circuit diagram of a wireless earset according to a third embodiment of the present disclosure. As shown in  FIG.  7   , the switching circuit  140  may comprise a third switch  144  and a fourth switch  145 . One end of the third switch  144  and one end of the fourth switch  145  are electrically connected to the control circuit  150 , the other end of the third switch  144  is electrically connected to the first antenna  120 , and the other end of the fourth switch  145  is electrically connected to the second antenna  130 . When the control circuit  150  turns on the third switch  144 , it also turns off the fourth switch  145 . When the control circuit  150  turns on the fourth switch  145 , it also turns off the third switch  144 . 
     In another embodiment, please refer to  FIG.  8   , which is a schematic circuit diagram of a wireless earset according to a fourth embodiment of the present disclosure. As shown in  FIG.  8   , in addition to the third switch  144  and the fourth switch  145 , the switching circuit  140  may further comprise a fifth switch  146  and a sixth switch  147 . The other end of the third switch  144  is further electrically connected to one end of the fifth switch  146 . The other end of the fourth switch  145  is further electrically connected to one end of the sixth switch  147 , and the other end of the fifth switch  146  and the other end of the sixth switch  147  are grounded. In order to realize that the control circuit  150  is configured to control the switching circuit  140  to ground the second antenna  130  when controlling the switching circuit  140  to be electrically connected to the first antenna  120 , the control circuit  150  turns off the fifth switch  146  and turns on and grounds the sixth switch  147  when it turns on the third switch  144  and turns off the fourth switch  145 . In order to realize that the control circuit  150  is configured to control the switching circuit  140  to ground the first antenna  120  when controlling the switching circuit  140  to be electrically connected to the second antenna  130 , the control circuit  150  turns on and grounds the fifth switch  146  and turns off the sixth switch  147  when it turns off the third switch  144  and turns on the fourth switch  145 . 
     In an embodiment, the switching circuit  140  may comprise a radio frequency switch chip. The radio frequency switch chip may be, but is not limited to, an integrated circuit including the single-pole double-throw switch  141 , the first switch  142 , and the second switch  143 , or an integrated circuit including the third switch  144 , the fourth switch  145 , the fifth switch  146 , and the sixth switch  147 . 
     In an embodiment, please refer to  FIG.  9   , which is a block diagram of a wireless earset according to another embodiment of the present disclosure. As shown in  FIG.  9   , the wireless earset  100  may further comprise a low-noise amplifier  160 , which is disposed in the housing  110  and is electrically connected between the control circuit  150  and the switching circuit  140 . The low-noise amplifier  160  is configured to amplify the first radio frequency signal, and the switching circuit  140  is configured to transmit the amplified first radio frequency signal to the first antenna  120  and the second antenna  130 . The switching circuit  140  is configured to receive the second radio frequency signal through the first antenna  120  or the second antenna  130 , and the low-noise amplifier  160  is configured to amplify the received second radio frequency signal and then transmit it to the control circuit  150 . The low-noise amplifier  160  has a good noise figure, which can amplify the first radio frequency signal and the second radio frequency signal while having a better suppression effect on low noise, so as to provide the beautiful sound quality. 
     In an embodiment, please refer to  FIG.  10   , which is a block diagram of a wireless earset according to another embodiment of the present disclosure. As shown in  FIG.  10   , in addition to the low-noise amplifier  160 , the wireless earset  100  may further comprise a filter  170 , which is disposed in the housing  110  and is electrically connected between the low-noise amplifier  160  and the switching circuit  140 . The filter  170  is configured to filter the first radio frequency signal amplified by the low-noise amplifier  160 , and the switching circuit  140  is configured to transmit the filtered first radio frequency signal to the first antenna  120  and the second antenna  130 . The switching circuit  140  is configured to receive the second radio frequency signal through the first antenna  120  or the second antenna  130 , the filter  170  is configured to filter the second radio frequency signal, and the low-noise amplifier  160  is configured to amplify the filtered second radio frequency signal, and then transmit it to the control circuit  150 . 
     In an embodiment, referring to  FIG.  10   , the wireless earset  100  may further comprise a first matching circuit  180  and a second matching circuit  190 , which are disposed in the housing  110 . The first matching circuit  180  is electrically connected between the first antenna  120  and the switching circuit  140 , and the second matching circuit  190  is electrically connected between the second antenna  130  and the switching circuit  140 . Therefore, the impedance matching of the first antenna  120  and the second antenna  130  is improved by the setting of the first matching circuit  180  and the second matching circuit  190 . 
     In summary, the wireless earset or headset of the embodiment of the present disclosure can solve the problem that the OTA performance and pattern of the antenna existing in the Bluetooth earset or headset are poor by the design of the first antenna and the second antenna that are set in different positions and have different radiation patterns (i.e., the dual antenna design), which can enhance the anti-interference ability of the wireless earset or headset. In addition, through the dual antenna design and the procedure of switching alternatively between the first antenna and the second antenna with the switching circuit (that is, the dual-antenna switching technology is adopted), the transmission or reception of radio frequency signals can be realized, the influence of in-band and out-of-band interference in the external environment on the antenna performance can be reduced, and the anti-interference ability is improved, thereby enhancing the user experience. Moreover, the switching circuit is controlled by the control circuit to ground the antenna not working, which increases the area of the ground plate of the working antenna and improves the radiation efficiency of the working antenna. 
     Although the present disclosure has been explained in relation to its preferred embodiment, it does not intend to limit the present disclosure. It will be apparent to those skilled in the art having regard to this present disclosure that other modifications of the exemplary embodiments beyond those embodiments specifically described here may be made without departing from the spirit of the disclosure. Accordingly, such modifications are considered within the scope of the disclosure as limited solely by the appended claims.