Abstract:
A wireless headset device capable of providing balanced stereo. The wireless headset connects with a stereo output device for giving balanced sounds on both left and right channels. The wireless headset has an encoder/decoder module which decompresses a digital audio package received from a wireless transceiver device into a stereo signal, and delivers it to a connection detecting module. The connection detecting module determines whether the wireless headset connects with the stereo output device. If the answer is negative, the stereo signal will be outputted by a single channel speaker of the wireless headset; otherwise, the signal will come out from the stereo output device which has a two-channel speaker.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention is related to a wireless headset, and more particular to a wireless headset device capable of providing balanced stereo and a method thereof. 
         [0003]    2. Description of Related Art 
         [0004]    Wireless communication technology is becoming more mature and convenient by the day, for example Bluetooth Communication is currently widely used for short range wireless communication technology applications; now consider in conjunction with mobile communication equipment functionality which is becoming more and more versatile, then it is easy to realize Bluetooth Technology are not only used for data synchronization, but are even more often used as a wireless transceiver agent between a wireless headset microphone and a mobile communication equipment (i.e. mobile phone). Especially consider that the current market has developed many brands of multi-functional mobile phone that can also listen to music, user can thus utilize single ear (single channel) hang-type Bluetooth hands-free headset, which can be used for in-coming Bluetooth mobile phone communication, and also can be used to listen to music coming from a Bluetooth mobile phone. 
         [0005]    Established to encourage, promote, and support Bluetooth Technology development, the Bluetooth Special Interest Group (Bluetooth SIG) specified the Advanced Audio Distribution Profile (A2DP), which defines how high quality audio can be streamed from one device to another over a Bluetooth connection, so that a Bluetooth equipment user can use a Bluetooth headset to listen to high quality music, as long as both the user&#39;s mobile phone and the wireless headset support A2DP. This kind of Bluetooth equipment can supply users with stereo output, which surpasses conventional mobile phones that can only broadcast in mono. 
         [0006]    However, the typical Bluetooth headset today consists of a single ear (single channel) hang-type headset, which by its physical nature has only one headset accessory for a single ear audio output, so even if the mobile phone and headset both support A2DP, the user will still not enjoy the full range of high audio quality music. Due to this limitation, the current market developed a headset that connects to both ears, and output the audio in both ears in a stereo headset device, such as the device disclosed by Republic of China Patent number M299999 “Duel Mode Headset Device”, which aims to solve the limitation of single ear (single channel) Bluetooth headset by connecting an extra single ear headset via a wire to the original single ear Bluetooth headset, thus achieving duel ear audio output. 
         [0007]    Although this method solves the limitation of single ear headset, but considering the solution: “The headset includes a first headset, a second headset, and a transmission line. The first headset includes a first housing; an interface module for receiving an audio signal; a signal processing module for separating the audio signal into a first channel signal and a second channel signal; an amplifying circuit for respectively amplifying the first channel signal and the second channel signal to generate a first amplified signal and a second amplified signal; and a first speaker for outputting audio according to the first amplified signal. The second headset includes a second housing; and a second speaker for outputting audio according to the second amplified signal. The transmission line is for transmitting the second amplified signal to the second headset;” the audio balance produced by this method from the audio channel output will be offset, because the first headset and second headset are made separately then tied together by a transmission line, which means the first amplified signal will arrive and be output by the first headset speaker first, while the second amplified signal will travel by the transmission line then arrive and be output by the second headset speaker with a delay. Furthermore, the amplifying circuit amplifies the first channel signal and the second channel signal separately via the signal processing module in the first headset, which mean there would be a further difference between the two audio output, such as one side would be louder and the other side would be more quiet, or one side would be more clear and the other side would have more noise, which result in interior output audio quality when compared to single piece duel ear stereo headset, and would more prone to cause user with audio discomfort; further consider the second connected ear piece headset have to be used in cooperation with the original first Bluetooth headset, if the second headset is not connected to the first headset, it would serve no audio function, which further limits this type of stereo headset&#39;s functionality. Due to the analysis described above, regarding how to produce wireless headset device capable of producing balanced and high quality stereo sound, there is certainly room for improvement and the limitation should be further analyzed. 
       SUMMARY OF THE INVENTION 
       [0008]    In order to improve upon the limitation described above and improve the product currently on the market place, the inventor proposes a simple wireless headset device capable of providing balanced stereo for a wireless headset. 
         [0009]    Such wireless headset device can connect a stereo output device in order to achieve the goal of stereo audio output. The wireless headset device includes—a communication module, a connection detection module, a first speaker unit and an audio output unit. The communication module includes a second transceiver module and an encoder/decoder module: the wireless headset device via the second transceiver module can transmit and receive information with the first transceiver module of an audio transceiver device, and thus establish communication with the audio transceiver device. The encoder/decoder module is used to decompress a digital audio package received from a second transceiver module into a stereo signal, whereby such a stereo signal can be decoded as a first channel signal or a second channel signal. 
         [0010]    Furthermore, the connection detection module is connected with the first speaker unit and the audio output unit of the wireless headset device, then according to whether the audio output unit has produced a connection signal or not, determines if the stereo signal should be output by the first speaker unit or output to the audio output unit. 
         [0011]    The stereo output device connected with the wireless headset device includes, an audio input unit, a second speaker unit, and a third speaker unit. The audio input unit establishes communication with the wireless headset device via the audio output unit, and receives the stereo signal that is output by the audio output unit of the wireless headset device; the above described connection signal is produced when the audio output unit and the audio input unit are connected. The audio input unit respectively sends the received stereo signals first and second channel signal to the second and third speaker unit for output. 
         [0012]    In order to provide a wireless headset device capable of providing balanced stereo, the present invention further provides a method for a wireless headset to output a stereo signal: a wireless headset device first receives a digital audio package form an audio transceiver device, then decompresses the package to a stereo signal, then determines via a connection detection module whether the wireless headset device is connected to a stereo output device, if not, then the stereo signal will be outputted by a mono speaker unit of the wireless headset device; if yes, then the stereo signal will be transmitted to the stereo output device, and outputted through the stereo audio device as a stereo signal via a second speaker unit and a third speaker unit simultaneously. 
         [0013]    In view of the method and device mentioned above, by connection to a stereo output device with dual speaker unit, and by a connection detection module detecting connection status between the speaker units, the proper audio output channel can be achieved, which can be used for wireless headset device that has only a single speaker but supports stereo functionality, and thus avoid the limitation of audio output by the stereo becoming unbalanced. 
         [0014]    Furthermore, because the wireless headset device only connects with the stereo output device, not only is the comfort of audio quality increased when listening to stereo audio, there will be no negative effect on the wireless headset device&#39;s original function of data transmission, and, for usability convenience, many single side speaker unit of wireless headset device has hands-free design, which also is not affected, and user can still enjoy the hands-free functionality convenience. 
         [0015]    Furthermore, because the stereo output device functions by receiving an audio signal and then broadcast accordingly, so that when the stereo output device is not connected with the wireless headset device, the stereo output device can function with other device with common connector (as shown by FIG.  4 &#39;s  2251  paired with  3001 , or FIG.  5 &#39;s  2253  paired with  3003 , or FIG.  6 &#39;s  2251 ,  3001 ,  2253 , and  3003  combination), or be directly connected with other audio/visual transceiver device for sound output, and is not limited to connect only with wireless headset device, thus the device possesses a high degree of practicality, and at the same time reduces the need to buy a separate stereo output device for each kinds of audio device. 
         [0016]    This method to achieve stereo output by externally connecting a stereo output device is completely different from the conventional method of simply connecting two mono output devices together by a wire, and audio quality, practicality, and convenience of the disclosed method are improved compared to the conventional method. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  shows an embodiment of a schematic diagram for a wireless headset device capable of providing balanced stereo according to the present invention; 
           [0018]      FIG. 2  shows another embodiment of a schematic diagram for a wireless headset device capable of providing balanced stereo according to the present invention; 
           [0019]      FIG. 3A  and  FIG. 3B  shows an embodiment of a circuit diagram for a wireless headset device capable of providing balanced stereo according to the present invention; 
           [0020]      FIG. 4  shows an embodiment of a structure connection representation diagram for a wireless headset device capable of providing balanced stereo according to the present invention; 
           [0021]      FIG. 5  shows another embodiment of a structure connection representation diagram for a wireless headset device capable of providing balanced stereo according to the present invention; 
           [0022]      FIG. 6  shows yet another embodiment of a structure connection representation diagram for a wireless headset device capable of providing balanced stereo according to the present invention; 
           [0023]      FIG. 7  shows a method flow chart for a wireless headset device capable of providing balanced stereo according to the present invention; 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]    In order to further explain the present invention&#39;s object, so that reader can easier understand the present invention&#39;s technique, the below embodiments will be used in conjunction with figures to explain by example regarding the present invention. 
         [0025]      FIG. 1  is an embodiment of a schematic diagram for a wireless headset device capable of providing balanced stereo according to the present invention: the wireless headset device  20  via wireless transmission technology (i.e. IEEE 802.11b) receives audio signals from audio transceiver device  10 , and connects to Stereo Output Device  30  in order to output the audio signal transmitted from the audio transceiver device  10 . 
         [0026]    Wireless headset device  20  includes—a communication module  22 , a connection detection module  215 , a first speaker unit  220 , an audio output unit  225 , and an audio receiver unit  230 . Communication module  22  further includes a second transceiver module  200  for transmitting and receiving an audio signal, an encoder/decoder module  205  used to respectively encode (compress) or decode (decompress) the audio signal transmitted or received from the second transceiver module  200 , and a signal converter unit  210  that will convert the decoded digital audio signal into an analog audio signal. The analog audio signal produced by the Communication module  22  will then be send to the connection detection module  215 , and the connection detection nodule  215  will determine whether the audio signal should be sent to the first speaker unit  220  or to the audio output unit  225  for output. 
         [0027]    Wireless headset device  20  via the second transceiver module  200  transmit and receive signal from first transceiver module  100  of audio transceiver device  10 , and thus establishes communication with the audio transceiver device  10 . 
         [0028]    The Stereo output device  30  includes an audio input unit  300 , a second speaker unit  305 , and a third speaker unit  310 , the stereo output device  30  via audio input unit  300  establishes communication with the audio output unit  225  of the wireless headset device  20 , thereby receiving audio signal output by the wireless headset device  20 , and transmitting the audio signal to the second speaker unit  305  and the third speaker unit  310 . 
         [0029]    In the present embodiment, the second transceiver module  200  of the communication module  22  receives an encoded digital audio package from audio transceiver device  10 , and send the package to the encoder/decoder module  205 , so that the digital audio package can be decompressed back to a stereo audio signal. 
         [0030]    The stereo audio signal is currently still a digital audio signal, and can be either a first channel signal or a second channel signal, used to create stereo sound effect. In order to adjust the audio signal so that it is fit for broadcast, a signal converter unit  210  coverts the stereo audio signal into analog audio signal. After the audio is converted to analog signal, it is send to connection detection module  215  to determine whether stereo output device  30  is connected with wireless headset device  20 ; when audio input unit  300  is connected with audio output unit  225 , the audio output unit  225  will produce a connection signal, and the connection detection module  215  will detect existence of the connection signal, in order to determine whether the wireless headset device  20  and the stereo output device  30  is connected. If the two are not connected (no detection of connection signal), then the connection detection module  215  will send the stereo audio signal that has been converted to analog audio signal to the first speaker unit  220  for output. However because wireless headset device  20  only has a single (mono) speaker unit at this point, so that even if wireless headset device  20  support stereo output, from the first speaker unit  220  alone the user would only hear mono audio output. 
         [0031]    On the other hand, if connection detection unit  215  determines that the wireless headset device  20 , through audio output unit  225 , is connected to the second speaker unit  305  and the third speaker unit  310  of stereo output device  30 , then connection detection module  215  would switch stereo audio output channel to audio output unit  225 , which result in stereo audio signal to be send from audio output unit  225  to stereo output device  30 . 
         [0032]    stereo output device  30  via audio input unit  300  receive stereo audio signal send by the audio output unit  225  of the wireless headset device  20 , and respectively send stereo audio signal&#39;s first channel signal and second channel to the second speaker unit  305  and third speaker unit  310 , so that user can directly utilize stereo output device  30  which posses dual (left and right) channel in order to listen to the full ranged and balanced stereo. 
         [0033]    The wireless headset device  20  also includes audio receiver unit  230 , for receiving an external audio input such as a user&#39;s voice, and the external audio input will be send to the signal converter unit  210  to be converted to a digital audio signal, then send to encoder/decoder module  205  to be encoded as package data, then through the second transceiver module  200  transmitted to the audio transceiver device  10  of the intended receiver. 
         [0034]      FIG. 2  is another embodiment of a schematic diagram for a wireless headset device capable of providing balanced stereo according to the present invention, and  FIG. 3A  and  FIG. 3B  together is the present embodiment&#39;s circuit diagram for a wireless headset device capable of providing balanced stereo according to the present invention, in order to avoid the circuit diagram appearing overly small and cause inconvenience in reading, so the present embodiment&#39;s circuit diagram will be split into two parts (U 1 _A and U 1 _B), and respective displayed in  FIG. 3A  and  FIG. 3B , but in actuality please understand that the component modules belongs on the same circuit chip. 
         [0035]    In the present embodiment, the wireless headset device  20  via Bluetooth technology achieves wireless transmitting and receiving functionality of wireless Bluetooth headset, which includes a Bluetooth module  40 , charger unit  405 , reset unit  410 , connection detection module  42 , mono speaker unit  420 , signal connection unit  425 , microphone unit  435 , flash memory unit  440 , light indicator unit  445 , battery unit  450 , voltage unit  455 , switch unit  460 , and oscillator unit  465 , wherein the connection detection module  42  further includes a first audio control unit  415  and a second audio control unit  430 . 
         [0036]    The headset through the antenna unit  400  of the Bluetooth module  40  receives a digital audio package and thus communicates with audio transceiver unit  10 , and the Bluetooth module  40  decode the received digital audio package to a digital stereo signal (which includes a left channel signal and a right channel signal) and then convert the stereo signal into an analog stereo signal (still with a left channel signal and a right channel signal). The antenna unit  400 &#39;s circuit diagram can be referenced as  400   a  of  FIG. 3A  (The below mentioned circuit diagram please reference  FIGS. 3A and 3B ). 
         [0037]    The second audio control unit  430  of the connection detection module  42  sends the left channel signal to the signal connection unit  425 ; and the first audio control unit  415  via multiplexer controls whether to send the right channel signal to the mono speaker unit  420  or to the signal connection unit  425 . If the wireless Bluetooth headset is not connected to stereo output device  30 , then first audio control unit  415  will send the right channel signal to the mono speaker unit  420  for output, but on the other hand if the two devices are connected, then the first audio control unit  415  will send the right channel signal to signal connection unit  425 , to complement the left channel signal that was also send to the signal connection unit  425 , and the signal connection unit  425  will simultaneously switch the dual channel signal to the externally connected stereo output device  30 , thus the right channel signal will be output from the right side speaker of the stereo output device  30  (such as second speaker unit  305 ), and the left channel signal will be output from the left side speaker of the stereo output device  30  (such as third speaker unit  310 ). The circuit diagram of schematic diagram component  415  to  430  can respectively be reference in component  415   a  to  430   a  of  FIGS. 3A and 3B . 
         [0038]    Microphone unit  435  is the result of audio receiver unit  230 &#39;s need of a biasing circuit and audio signal, and the associated circuit diagram can be referenced in  435   a  of  FIG. 3B . Charger unit  405  provide voltage for Bluetooth module  40 , for when the battery is charging, please reference  405   a  of  FIG. 3A ; reset unit  410  is for resetting the Bluetooth module  40  while charging, please reference  410   a  of  FIG. 3B . Flash memory unit  440  is for storing the software of Bluetooth module  40 , please reference  440   a  of  FIG. 3B ; there is also the light indicator unit  445  which control the LED to indicate various status regarding the wireless Bluetooth headset, please reference  445   a  of  FIG. 3B ; battery unit  450  supply the overall required battery for the wireless Bluetooth Headset while it is functioning, please reference  450   a  of  FIG. 3B ; voltage unit  455  uses the voltage supplied by battery unit  450 , and provide the Bluetooth module  40  with the necessary operating voltage, please reference  455   a  of  FIG. 3A . 
         [0039]    Furthermore, there is the switch unit  460  and the oscillator unit  465 , wherein the switch unit  460  provides control for the wireless Bluetooth headset that require switching or adjustment, such as Power on/off, device pairing, volume adjustment, etc. Please reference  460   a  of  FIG. 3A ; the oscillator unit  465  provides the clock needed by the Bluetooth module  40 , please reference  465   a  of  FIG. 3B . 
         [0040]      FIG. 4  is an embodiment of a structure connection representation diagram for a wireless headset, device capable of providing balanced stereo according to the present invention, please view in conjunction with  FIG. 1 . 
         [0041]    The present embodiment is a wireless Bluetooth headset device, which includes a single ear (single channel) Bluetooth headset  2  that supports A2DP Bluetooth stereo output and a dual channel (dual ear) stereo headset  3 . Single ear Bluetooth headset  2  via second transceiver module  200  of communication module  22 , transmit and receive data with first transceiver module  100  of mobile phone  1 , thus achieve communication with mobile phone  1 . The communication module  22  is a Bluetooth wireless communication module. Mobile phone  1  which is capable of broadcasting music sends the music audio package to the single ear Bluetooth headset  2 , then encoder/decoder module  205  decodes the package, and decompress it back to stereo audio signal, and using A2DP&#39;s decoder standard calculate the first channel signal and second channel signal needed for the stereo, and then through signal converter unit  210  convert the stereo audio signal to analog for output by speaker. 
         [0042]    Before the converted stereo audio signal is output to speaker, connection detection module  215  will detect if the single ear Bluetooth headset  2  is connected to the dual channel stereo headset  3  via USB female connector  2251  and USB male connector  3001 , if not, then the stereo audio signal will only be output from the speaker  2001  of single ear Bluetooth headset  2  as mono; on the other hand if the single ear Bluetooth headset  2  and the dual channel stereo headset  3  are connected by the USB interface, then the stereo audio signal will be send to the dual channel stereo headset  3 , and the first channel signal (left) and second channel signal (right) of the stereo audio signal will respectively be output by the second speaker  3051  and the third speaker  3101 . 
         [0043]    When user plug dual channel stereo headset  3  into the single ear Bluetooth headset  2 , and use the dual channel stereo headset  3  to listen to audio output of mobile phone  1 , not only can the user experience the natural spatial effect (left and right direction) of stereo, but the original single ear Bluetooth headset  2  can be clipped on the collar, or via maintaining a reasonable length of the headset wire, the microphone  2301  that was built-in can still be used to input audio signal, so that the hands-free functionality is still maintained. Furthermore, if the single ear Bluetooth headset  2  and the duel channel stereo headset  3  are connected, when mobile phone  1  receives a phone call, the sound can be output just like the music (digital audio package) described previously, so that user can use the dual channel headset  3  to receive phone call, and then use the microphone  2301  of the single ear Bluetooth headset  2  to speak. However understand that the audio transceiver device  10  of the system is not limited to mobile phone system, it can be any other audio transceiver device that is connected wirelessly, such as MP3, MP4 music broadcasting device. 
         [0044]    Also, the above described method of connecting single ear Bluetooth headset  2  and dual channel stereo headset  3  is not limited to connecting USB male connector  3001  with USB female connector  2251 , of course there are other common interface for connecting, transmitting, and receiving audio signal, for example:  FIG. 5  shows a common TRS female connector  2253  of another single ear Bluetooth headset  2   a  connected with an TRS male connector  3003  (tip-ring-sleeve connector, are referred as phone plug in US and jack plug in UK, 3.5 mm TRS connector is commonly used by both mono and stereo headset) of another dual channel stereo headset  3   a ; or for example as shown by  FIG. 6 , via an adapter  315  provide an USB male connector  3001  and a TRS female connector  2253 , so that the TRS male connector  3003  of dual channel stereo headset  3   a  can first connect to TRS female connector of adapter  315 , then the USB male connector  3001  of adapter  315  can connect to the USB female connector  2251  of single ear Bluetooth headset  2 , which can be convenient since TRS male connector  3003  is very common. 
         [0045]    In order to avoid undue overlapping of device component: the above mentioned single ear Bluetooth headset  2  and  2   a  from  FIG. 4 to 6  was not drawn with the single ear hook, since the single ear hook itself is outside the scope of the present invention. 
         [0046]      FIG. 7  is an embodiment of a method flow chart for a wireless headset device capable of providing balanced stereo according to the present invention: the wireless headset device first receive a digital audio package from audio transceiver device  10  (S 701 ), then the encoder/decoder module  205  decompresses the digital audio package to a stereo signal, and decodes the package as either a first channel signal or a second channel signal (S 701 ); then the connection detection module  215  determines if stereo output device  30  is connected with the wireless headset device  20  (S 705 ); if the two are not connected, then the stereo signal will be output by the first speaker unit  220  (a.k.a. mono/single channel speaker) of the wireless headset device  20  (S 707 ); otherwise if the two are connected, then the connection detection module  215  would switch the channel for audio signal output, and the stereo signal is sent to the stereo output device  30 , so that the first and second channel signal are respectively output by the second speaker unit and the third speaker unit (S 709 ). 
         [0047]    Wherein, after the stereo signal has been decoded as first channel signal and second channel signal, there would be a further step of sending the signal to a signal converter unit  210  to be converted to analog signal, in order for the first speaker unit  220  or the dual channel stereo output device  30  to output. 
         [0048]    Furthermore, in the step where connection detection module  215  determines whether the two devices are connected (S 705 ), the determination is based on whether a connection signal is received, the connection signal in turn is produced when an audio input unit  300  of stereo output device  30  is connected with an audio output unit  225  of the wireless headset device  20 . 
         [0049]    As per the detailed descriptions and embodiments described above, a simple and effective method has been disclosed, which allows a wireless headset with mono channel to output stereo sound effect, and the stereo signal produced according to the present invention&#39;s technique, will not cause right and left channel to have unbalanced sound quality or uneven volume, and can allow for user desire to be plugged in (for stereo sound) or taken off (for mono sound), which greatly increase the usability of single ear (single channel) hang type headset&#39;s usability. 
         [0050]    While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures.