Abstract:
An earphone able to function as a left or as a right earphone and receive sound channels accordingly comprises a processing unit, a capturing unit, and a touch sensor. The capturing unit gets images of ear canal. The touch sensor senses a first and second ear contact points. The processing unit applies sensor readings and captured images to an imaginary circle having a default radius, to determine whether earphone is being worn in the right or in the left ear. The output of sound can be channeled appropriately to an earphone in the left ear or in the right ear or both. A method and a system for detecting wearing state are also provided.

Description:
FIELD 
     The subject matter herein generally relates to systems and methods for detecting wearing state of earphone and earphones using the same. 
     BACKGROUND 
     Earphones are usually stereophonic. If a user wears the earphone on an opposite ear, a sound field that the user hears will be opposite. In order to identify left and right channels of the earphone, the earphone is generally marked L or R to identify the left or right channels. User often cannot see L or R logo under environment with low lighting, it is likely earphones are worn in reverse. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present disclosure are better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the views. 
         FIG. 1  is a structural diagram of an exemplary embodiment of an earphone. 
         FIGS. 2 a  and 2 b    are images of an auditory meatus. 
         FIG. 3  is a schematic view of the earphone of  FIG. 1  being worn on the right ear. 
         FIG. 4  is a block diagram of the earphone of  FIG. 1 . 
         FIG. 5  is a block diagram of a system for detecting wearing states of the earphone of  FIG. 1 . 
         FIG. 6 a -6 h    are schematic diagrams for detecting wearing states of the earphone of  FIG. 1 . 
         FIG. 7  is a flowchart of a first method for detecting wearing states of the earphone of  FIG. 1 . 
         FIG. 8  is a flowchart of a second method for detecting wearing states of the earphone of  FIG. 1 . 
         FIGS. 9 and 10  cooperatively constitute a single flowchart of a pairing method for the earphone pairing with a master device. 
     
    
    
     DETAILED DESCRIPTION 
     It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the exemplary embodiments described herein. However, it will be understood by those of ordinary skill in the art that the exemplary embodiments described herein can be practiced without these specific details. In other instances, methods, procedures, and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the exemplary embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts have been exaggerated to better illustrate details and features of the present disclosure. 
     Several definitions that apply throughout this disclosure will now be presented. 
     The term “coupled” is defined as connected, whether directly or indirectly through intervening components, and is not necessarily limited to physical connections. The connection can be such that the objects are permanently connected or releasably connected. The term “comprising,” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series, and the like. 
       FIG. 1  shows an exemplary embodiment of an earphone  100 . The earphone  100  can include a shell  10 . In this exemplary embodiment, the shell  10  can include a front shell  102  and a back shell  104 . A receiving space  106  can be cooperatively defined in the front shell  102  and the back shell  104 . 
     The earphone  100  can further include a capturing unit  20 . The capturing unit  20  can be mounted in the receiving space  106  and adjacent to a free end of the front shell  102 . The front shell  102  can further define an opening  1022  at the free end of the front shell  102 . The opening  1022  and the receiving space  106  are in air communication with each other. The opening  1022  allows the capturing unit  20  to capture images of auditory meatus of an external ear of a user. In this exemplary embodiment, the capturing unit  20  can be a thermal imaging device. The thermal imaging device can be an apparatus for performing photographic imaging according to infrared rays emitted from the auditory meatus of the user. An exemplary auditory meatus image captured by the thermal imaging device is shown on  FIG. 2 a   . In at least one exemplary embodiment, the capturing unit  20  can be green ray camera, but is not limited to the examples provided herein. An exemplary image of auditory meatus captured by the green ray camera is shown on  FIG. 2 b   . The capturing unit  20  can be configured to capture auditory meatus images of the external ear of the user and further obtain an auditory meatus feature point N, for example, from the captured auditory meatus images. 
     Referring to  FIG. 1 , the earphone  100  can include a touch sensor  30 . The touch sensor  30  can be on an outside surface of the back shell  104 . The touch sensor  30  can include a number of touch sensing bars. As shown in  FIG. 3 , the touch sensor  30  can be configured to touch a first contact point A, which is where the touch sensor  30  contacts an antitragus  310  of an external ear  300  of the user, and a second contact point B, which is where the touch sensor  40  contacts a tragus  320  of the external ear  300  of the user. 
     As shown in  FIG. 4 , the earphone  100  can further include a storage unit  40 . The storage unit  40  can be used to store the first contact point A and the second contact point B. The storage unit  40  can be further used to store an imaginary circle, an imaginary ligature, an imaginary radial reference vector, and the like. 
     In at least one exemplary embodiment, the storage unit  40  can be an internal storage system, such as a flash memory, a random access memory (RAM) for temporary storage of information, and/or a read-memory (ROM) for permanent storage of information. 
     In at least one exemplary embodiment, the storage unit  40  can also be a storage system, such as a hard disk, a storage card, or a data storage medium. The storage unit  40  can include volatile and/or non-volatile storage devices. 
     In at least one exemplary embodiment, the storage unit  40  can include two or more storage devices such that one storage device is a memory and the other storage device is a hard drive. Additionally, the storage unit  40  can be either entirely or partially external relative to the earphone  100 . 
     As shown in  FIG. 4 , the earphone  100  can further include a processing unit  50 . The processing unit  50  can be electrically coupled to the capturing unit  20 , the touch sensor  30 , and the storage unit  40 . The processing unit  50  can be a central processing unit, a digital signal processor, or a single chip, for example. 
     The earphone  100  can further include a gravity sensor  60 . The gravity sensor  60  can be received in the receiving space  106  and electrically coupled to the processing unit  50 . In this exemplary embodiment, the gravity sensor  60  can be a three axis sensor. The gravity sensor  60  can be configured to sense a gravitational acceleration in direction G of the earphone  100  as shown in  FIGS. 6 a   - 6   h.    
     The earphone  100  can further include a BLUETOOTH device (first Bluetooth unit  70 ). The first Bluetooth unit  70  can be received in the receiving space  106  and further electrically coupled to the processing unit  50 . The earphone  100  can be configured to communicate with a master device  200 . The master device  200  can include a second Bluetooth unit  210 . The first Bluetooth unit  70  can be configured to communicate with the second Bluetooth unit  210  of the master device  200 . 
     The earphone  100  can further include a first Human Body Communication (HBC) unit  80 . The first HBC unit  80  can include a number of Human Body sensing bars  81  on the outside surface of the back shell  104  and an HBC controller  83  in the receiving space  106 . The HBC controller  83  can be electrically coupled to the Human Body sensing bars  81  and the processing unit  50 . The master device  200  can further include a second HBC unit  220 . The first HBC unit  80  can communicate with the second HBC unit  220  of the master device  200 . 
     The earphone  100  can further include a pairing button  90 . The pairing button  90  can be electrically coupled to the processing unit  50 . 
     In at least one exemplary embodiment, the earphone  100  can further include a number of electrical components for other functions, the details are omitted for simplification. 
       FIG. 5  shows a wearing state detection system  5 . The wearing state detection system  5  can include a plurality of modules. The plurality of modules can include an imaginary circle drawing module  51 , an ear determining module  52 , an audio channel switching module  53 , a start controlling module  54 , a sound transmitting module  55 , and a pairing module  56 . The imaginary circle drawing module  51 , the ear determining module  52 , the audio channel switching module  53 , the start controlling module  54 , the sound transmitting module  55 , and the pairing module  56  can be stored in the storage unit  40  of the earphone  100 , and further applied on the processing unit  50  of the earphone  100 . The modules of the wearing state detection system  5  can include separated functionalities represented by hardware or integrated circuits, or as software and hardware combinations, such as a special-purpose processor or a general-purpose processor with special-purpose firmware. 
     As shown in  FIGS. 6 a -6 h   , the imaginary circle drawing module  51  can digitally draw an imaginary circle M in a two-dimensional plane. Therein, the imaginary circle M can have a center O and a default radius. The circumference of the imaginary circle M can be drawn to intersect the first contact point A and the second contact point B. The auditory meatus feature point N can be within the imaginary circle M. 
     An imaginary line W is defined between the center O and the auditory meatus feature point N. The ear determining module  52  can be configured to rotate the imaginary circle M together with the first contact point A, the second contact point B, and the auditory meatus feature point N about the center O until the auditory meatus feature point N is just above the center O. As shown in  FIG. 6 a   , the ear determining module  52  can be further configured to determine that the earphone  100  is worn on the left ear when the auditory meatus feature point N is just above the center O and the second contact point B is on the left side of the imaginary line W. As shown in  FIG. 6 b   , the ear determining module  52  can be further configured to determine that the earphone  100  is worn on the right ear when the auditory meatus feature point N is just above the center O and the second contact point B is on the right side of the imaginary line W. 
     The audio channel switching module  53  can be configured to switch an audio channel to a left channel when the ear determining module  52  determines that an earphone  100  is worn on the left ear. The sound track switching module  53  can be further configured to switch an audio channel to a right channel when the ear determining module  52  determines that an earphone  100  is worn on the right ear. 
     The imaginary circle M has an imaginary radial reference vector Z. The imaginary radial reference vector Z can be parallel to the gravitational acceleration direction G of the earphone  100  when the earphone  100  is worn by a standing user, as shown in FIGS.  6   a - 6   b . That is, when an angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 0°, the ear determining module  52  can determine that the user of the earphone  100  is standing, and the auditory meatus feature point N is just above the center O. The ear determining module  52  can further determine whether the earphone  100  is worn on the left ear or the right ear according to the relationship between the second contact point B and the imaginary line W. 
     As shown in  FIG. 6 c   , when an angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 90° and the auditory meatus feature point N is just left side of the center O, the ear determining module  52  can determine that the user of the earphone  100  is lying down and the earphone  100  is worn on the left ear. As shown in  FIG. 6 d   , when an angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 90° and the auditory meatus feature point N is just right side of the center O, the ear determining module  52  can determine that the user of the earphone  100  is lying down and the earphone  100  is worn on the right ear. 
     As shown in  FIG. 6 e   , when an angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 180° and the auditory meatus feature point N is just below the center O, the ear determining module  52  can determine that the user of the earphone  100  is upside down, and the earphone  100  is worn on the left ear, for example, the user is doing yoga exercise in an upside down position having the earphone  100  on the left ear. As shown in  FIG. 6 f   , when an angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 180° and the auditory meatus feature point N is just below the center O, the ear determining module  52  determines that the user of the earphone  100  is upside down, and the earphone  100  is worn on the right ear. 
     As shown in  FIG. 6 g   , when an angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 270°, and the auditory meatus feature point N is right side of the center O, the ear determining module  52  determines that the user of the earphone  100  is prostrate, and the earphone  100  is being worn on the left ear. As shown in  FIG. 6 h   , when an angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 270°, and the auditory meatus feature point N is left side of the center O, the ear determining module  52  determines that the user of the earphone  100  is prostrate, and the earphone  100  is worn on the right ear. 
     In this exemplary embodiment, as shown in  FIG. 6 a   , the ear determining module  52  determines that the earphone  100  is worn on the left ear under certain conditions (left ear conditions). The left ear conditions are when the angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 0°, the second contact point B is on the left side of the imaginary line W, and the first contact point A is on the right side of the imaginary line W. As shown in  FIG. 6 b   , the ear determining module  52  determines that the earphone  100  is worn on the right ear when certain conditions (right ear conditions) are met. The right ear conditions are when the angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 0°, the second contact point B is on the right side of the imaginary line W, and the first contact point A is on the left side of the imaginary line W. 
     In at least one exemplary embodiment, the ear determining module  52  determines that the earphone  100  is worn on the left ear when the angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 0°, and the second contact point B and the first contact point A are both on the left side of the imaginary line W. The ear determining module  52  determines that the earphone  100  is worn on the right ear when the angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 0°, and the second contact point B and the first contact point A are both on the right side of the imaginary line W. 
     The start controlling module  54  can be configured to activate the earphone  100  to output sound when the ear determining module  52  determines that the earphone  100  has been worn on the left ear or on the right ear. 
     The pairing module  56  can be configured to control the first Bluetooth unit  70  to determine whether the second Bluetooth unit  210  of the master device  200  is in an inquiring state when the pressing button  90  is pressed. Therein, the master device  200  can be but is not limited to being a telephone, a tablet computer, or the like. Therein, the inquiring state is a state where the pressing button of the master device  200  is pressed, and the master device  200  is at the moment waiting for pairing to the earphone  100 . 
     The pairing module  56  can be further configured to control the first Bluetooth unit  70  to pair with the second Bluetooth unit  210  of the master device  200  when it is determined that the master device  210  is in an inquiring state. 
     The pairing module  56  can be further configured to control the first HBC unit  80  to pair with the second HBC unit  220  of the master device  200  when it is determined that the second Bluetooth unit  210  of the master device  200  is not in an inquiring state. 
     The pairing module  56  can be configured to control the first Bluetooth unit  70  to determine whether the second Bluetooth unit  210  of the master device  200 , which has been paired previously, can be directly coupled with when the pressing button  90  is not pressed. The pairing module  56  can be configured to transmit the wearing state of the earphone  200  to the master device  200  through Service Discovery Protocol when the second Bluetooth unit  210  of the master device  200 , which has been paired previously, can be directly coupled with, such that the first Bluetooth unit  70  can be coupled to the second Bluetooth unit  210  of the master device  200  directly. 
     The pairing module  56  can be further configured to control the first HBC unit  80  to pair with the second HBC unit  220  of the master device  200  when it is determined that a direct coupling of the first Bluetooth unit  70  to the second Bluetooth unit  210  of the master device  200  is not available. 
     Before the first HBC unit  80  of the earphone  100  pairs with the second HBC unit  220  of the master device  200 , the first HBC unit  80  of the earphone  100  first waits and receives a beacon signal transmitted by the second HBC unit  220  of the master device  200 . The beacon signal refers to signal sent periodically in the field of communications. When the first HBC unit  80  of the earphone  100  receives the beacon signal transmitted by the second HBC unit  220  of the master device  200 , the first HBC unit  80  of the earphone  100  verifies the existence of the second HBC unit  220  of the master device  200 . The first HBC unit  80  of the earphone  100  can be then coupled to the second HBC unit  220  of the master device  200 . If the first HBC unit  80  of the earphone  100  has not received the beacon signal in a predefined time duration, the pairing module  56  can be further configured to control the first HBC unit  80  of the earphone  100  to transmit a wake up signal to the second HBC unit  220  of the master device  200 . The second HBC unit  220  of the master device  200  transmits a beacon signal to the first HBC unit  80  of the earphone  100  when the second HBC unit  220  of the master device  200  receives the wake up signal. In order to save electricity, when there is no signal needed to be transmitted by the second HBC unit  220  of the master device  200 , the transmitting function of the second HBC unit  220  can be closed, and the receiving function of the second HBC unit  220  can be kept open. If the first HBC unit  80  of the earphone  100  has not received the beacon signal in a predefined time duration after transmitting the wake up signal, a new wake up signal can be transmitted again by the first HBC unit  80  of the earphone  100 . The predefined time duration can be extended until a beacon signal transmitted by the second HBC unit  220  of the master device  200  is received. 
     When the first HBC unit  80  of the earphone  100  receives the beacon signal, the pairing module  56  can be further configured to control the earphone  100  to synchronize time with the master device  200 . The pairing module  56  can be further configured to control the first HBC unit  80  of the earphone  100  to obtain the available time slot from the beacon signal, and further transmit a connection request through the time slot to the second HBC unit  220  of the master device  200 . 
     The second HBC unit  220  of the master device  200  can confirm the connection request, and can assign a time slot to the first HBC unit  80  of the earphone  100  for sound transmitting. 
     The sound transmitting module  55  can be configured to select one of the first Bluetooth unit  70  and the first HBC unit  80  to transmit sound data. The transmission rate of the first HBC unit  80  is different for different users as different users have different body capacity effects. 
     The sound transmitting module  55  can be configured to control the first Bluetooth unit  70  to transmit the sound data when the transmission rate of the first HBC unit  80  is less than a predefined value. 
     The sound transmitting module  55  can be configured to control the first HBC unit  80  to transmit the sound data when the transmission rate of the first HBC unit  80  is greater than the predefined value. 
       FIG. 7  illustrate a flowchart of a wearing state detection method. The wearing state detection method is provided by way of example, as there are a variety of ways to carry out the method. The wearing state detection method described below can be carried out using the configurations illustrated in  FIG. 5 , for example, and various elements of these figures are referenced in explaining the example method. Each block shown in  FIG. 7  represents one or more processes, methods, or subroutines carried out in the example method. Furthermore, the illustrated order of blocks is by example only and the order of the blocks can be changed. Additional blocks may be added or fewer blocks may be utilized, without departing from this disclosure. The example method can begin at block  710 . 
     At block  710 , the auditory meatus images of the external ear  300  of the user are captured and the auditory meatus feature point N is further obtain from the captured auditory meatus images. In this exemplary embodiment, the capturing unit  20  can be a thermal imaging devices. The thermal imaging device can be an apparatus for performing photographic imaging according to infrared rays emitted from an aimed object. In at least one exemplary embodiment, the capturing unit  20  can be green ray camera. 
     At block  720 , the first contact point A, which is where the touch sensor  30  contacts the antitragus  310  of the external ear  300  is sensed, and the second contact point B, which is where the touch sensor  40  contacts the tragus  320  of the external ear  300  is sensed. In this exemplary embodiment, the touch sensor  30  can be on an outside surface of the back shell  104 , and can touch a first contact point A, which is where the touch sensor  30  contacts the antitragus  310  of the external ear  300 , and a second contact point B, which is where the touch sensor  40  contacts the tragus  320  of the external ear  300 . 
     At block  730 , the imaginary circle M is drawn in the two-dimensional plane. Therein, the imaginary circle M has a center O and a default radius. The circumference of the imaginary circle M intersects the first contact point A and the second contact point B. The auditory meatus feature point N is within the imaginary circle M. 
     At block  740 , the imaginary circle M together with the first contact point A, the second contact point B and the auditory meatus feature point N is rotated about the center O, until the auditory meatus feature point N is just above the center O. 
     At block  750 , an imaginary line W between the center O and the auditory meatus feature point N is defined. Determine whether the second contact point B is on the left side of the imaginary line W, if yes, the process goes to block  760 , otherwise, the process goes to block  770 . 
     At block  760 , it is determined that the earphone  100  is worn on the left ear. 
     At block  770 , it is determined that the earphone  100  is worn on the right ear. 
       FIG. 8  illustrates a flowchart of a wearing state detection method. The wearing state detection method is provided by way of example, as there are a variety of ways to carry out the method. The wearing state detection method described below can be carried out using the configurations illustrated in  FIG. 5 , for example, and various elements of these figures are referenced in explaining the example method. Each block shown in  FIG. 8  represents one or more processes, methods, or subroutines carried out in the example method. Furthermore, the illustrated order of blocks is by example only and the order of the blocks can be changed. Additional blocks may be added or fewer blocks may be utilized, without departing from this disclosure. The example method can begin at block  810 . 
     At block  810 , the auditory meatus images are captured and the auditory meatus feature point N is further obtain from the captured auditory meatus images. In this exemplary embodiment, the capturing unit  20  can be a thermal imaging device. The thermal imaging device can be an apparatus for performing photographic imaging according to infrared rays emitted from an aimed object. In at least one exemplary embodiment, the capturing unit  20  can be green ray camera. 
     At block  820 , the first contact point A, which is where the touch sensor  30  contacts the antitragus  310  of the external ear  300  is sensed, and the second contact point B, which is where the touch sensor  40  contacts the tragus  320  of the external ear  300  is sensed. In this exemplary embodiment, the touch sensor  30  on an outside surface of the back shell  104  can touch a first contact point A, which is where the touch sensor  30  contacts the antitragus  310  of the external ear  300 , and a second contact point B, which is where the touch sensor  40  contacts the tragus  320  of the external ear  300 . 
     At block  830 , the gravitational acceleration direction G of the earphone  100  is sensed. In this exemplary embodiment, the gravity sensor  60  in the earphone  100  can sense the gravitational acceleration direction G of the earphone  100 . 
     At block  840 , the imaginary circle M is drawn in the two-dimensional plane according to the auditory meatus feature point N, the first contact point A and the second contact point B. Therein, the imaginary circle M has a center O and a default radius. The circumference of the imaginary circle M intersects the first contact point A and the second contact point B. The auditory meatus feature point N is within the imaginary circle M. 
     At block  850 , the imaginary circle M together with the first contact point A, the second contact point B and the auditory meatus feature point N are rotated about the center O, until the auditory meatus feature point N is just above the center O, and the angle between the imaginary radial reference vector Z and the gravitational acceleration direction G is 0°. 
     At block  860 , an imaginary line W between the center O and the auditory meatus feature point N is defined. Determine whether the second contact point B is on the left side of the imaginary line W, if yes, the process goes to block  870 , otherwise, the process goes to block  880 . 
     In at least one exemplary embodiment, determine whether the first contact point A and the second contact point B are both on the left side of the imaginary line W, if yes, the process goes to block  870 , otherwise, the process goes to block  880 . 
     At block  870 , it is determined that the earphone  100  is worn on the left ear. 
     At block  880 , it is determined that the earphone  100  is worn on the right ear. 
       FIGS. 9 and 10  cooperatively constitute a signal flowchart of a pairing method applied on the earphone  100 . The pairing method is provided by way of example, as there are a variety of ways to carry out the method. The pairing method described below can be carried out using the configurations illustrated in  FIG. 5 , for example, and various elements of these figures are referenced in explaining the example method. Each block shown in  FIGS. 9 and 10  represents one or more processes, methods, or subroutines carried out in the example method. Furthermore, the illustrated order of blocks is by example only and the order of the blocks can be changed. Additional blocks may be added or fewer blocks may be utilized, without departing from this disclosure. The example method can begin at block  910 . 
     At block  910 , the earphone  100  is activated when the earphone  100  to output sound has been worn on the left ear or on the right ear, and determine whether the pressing button  90  is pressed, if yes, the process goes to block  920 , otherwise, the process goes to block  960 . 
     At block  920 , the second Bluetooth unit  210  of the master device  200  is determined whether to be in an inquiring state. If yes, the process goes to block  930 , otherwise, the process goes to block  940 . 
     At block  930 , the first Bluetooth unit  70  of the earphone  100  is controlled to pair with the second Bluetooth unit  210  of the master device  200 , and the process goes to block  960 . 
     At block  940 , the first Bluetooth unit  70  of the earphone  100  is controlled to determine whether the second Bluetooth unit  210  of the master device  200 , which had been paired previously, can be directly coupled with. If yes, the process goes to block  950 , otherwise, the process goes to block  960 . 
     At block  950 , the wearing state of the earphone  200  is transmitted to the master device  200  through Service Discovery Protocol, such that the first Bluetooth unit  70  is coupled to the second Bluetooth unit  210  of the master device  200  directly, and then the process goes to block  960 . 
     At block  960 , the first HBC unit  80  of the earphone  100  determines whether the beacon signal has been received in a predefined time duration. If yes, the process goes to block  990 , otherwise, the process goes to block  970 . 
     At block  970 , the first HBC unit  80  of the earphone  100  is controlled to transmit a wake up signal to the second HBC unit  220  of the master device  200 . 
     At block  980 , the second HBC unit  220  of the master device  200  transmits a beacon signal to the first HBC unit  80  of the earphone  100 , and then the process goes to block  990 . 
     At block  990 , when the first HBC unit  80  of the earphone  100  receives the beacon, the earphone  100  is controlled to synchronize time with the master device  200 , the first HBC unit  80  of the earphone  100  is controlled to obtain the available time slot from the beacon signal, and to further transmit a connection request through the time slot to the second HBC unit  220  of the master device  200 . 
     At block  9100 , the second HBC unit  220  of the master device  200  confirms to the connection request, and assigns a time slot to the first HBC unit  80  of the earphone  100  for sound transmitting. 
     At block  9110 , the transmission rate of the first HBC unit  80  is determined whether to be greater than a predefined value. If yes, the process goes to block  9120 , otherwise, the process goes to block  9130 . 
     At block  9120 , the first HBC unit  80  is controlled to transmit the sound data. 
     At block  9130 , the first Bluetooth unit  70  of the earphone  100  is controlled to transmit the sound data. 
     At block  9140 , the earphone  100  is determined whether to be removed from the user&#39;s ear through the touch sensor  40 . If yes, the process goes to block  9150 , otherwise, the process continues to block  9140 . 
     At block  9150 , the earphone  100  is controlled to stop outputting sound, and the remaining sound is switched to stereo out. 
     The exemplary embodiments shown and described above are only examples. Many details are often found in the art such as the features of system and method for detecting ear location of earphone and rechanneling connections accordingly and earphone using same. Therefore, many such details are neither shown nor described. Even though numerous characteristics and advantages of the present technology have been set forth in the foregoing description, together with details of the structure and function of the present disclosure, the disclosure is illustrative only, and changes may be made in the detail, especially in matters of shape, size, and arrangement of the parts within the principles of the present disclosure, up to and including the full extent established by the broad general meaning of the terms used in the claims. It will therefore be appreciated that the exemplary embodiments described above may be modified within the scope of the claims.