Patent Publication Number: US-2012045990-A1

Title: Intelligent Audio Routing for Incoming Calls

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to wireless communication devices, and more particularly to wireless communication devices configured to communicate with hands-free headsets over a short-range wireless interface. 
     BACKGROUND 
     Cellular communication devices, such as cellular telephones, are commonly used by many people. Often times, people connect a variety of different peripheral devices so that they may utilize their cellular device more comfortably. One such peripheral device is a Bluetooth® headset. As is known in the art, Bluetooth® headsets include a microphone and a speaker to allow users to operate their cellular devices in a “hands-free” mode. This mode of operating a cellular telephone is very beneficial for many users, especially those who operate motor vehicles. However, drivers are not the only beneficiaries of this technology. Many users wear Bluetooth® headsets during the day because they find it more comfortable to use than having to hold a device against their ear. 
     As is known in the art, the cellular telephone will usually establish a short-range communication link with the headset. Thus, when paired with the cellular telephone, the audio signals that are associated with an incoming call are generally routed from the cellular telephone to the speaker in the headset. However, there could be situations wherein a user may want to dynamically route incoming audio signals to a speaker at the cellular telephone instead of to the speaker at the headset. 
     SUMMARY 
     The present invention selectively routes audio signals associated with an incoming call either to a speaker integrated with the receiving wireless communication device, or to a speaker integrated with a hands-free headset paired with the device. The decision on which speaker to direct the audio signals is based on the placement of a microphone relative to a user&#39;s mouth. 
     In one embodiment, the present invention provides a wireless communication device configured to communicate short-range wireless signals with a corresponding headset. In this embodiment, the wireless communication device comprises a microphone, a speaker, a short-range transceiver configured to communicate with the headset, and a controller. The controller is configured to measure an audio reception quality for the microphone at the wireless communication device, measure an audio reception quality for a microphone at the headset, and route audio signals associated with the incoming call to the speaker at the wireless communication device, or to a speaker at the headset, based on the measured audio reception qualities. 
     In one embodiment, the controller is further configured to determine which of the microphones is positioned closest to the user&#39;s mouth based on the measured audio reception qualities, and route the audio signals associated with the incoming call to the speaker associated with the microphone that is closest to the user&#39;s mouth. 
     By way of example, the controller is configured to route the audio signals associated with the incoming call to the speaker at the wireless communication device if the controller determines that the microphone at the wireless communication device is closer to the user&#39;s mouth than the microphone at the headset. 
     Similarly, the controller is configured to route the audio signals associated with the incoming call to the speaker at the headset if the controller determines that the microphone at the headset is closer to the user&#39;s mouth than the microphone at the wireless communication device. 
     In one embodiment, the controller is configured to route the audio signals associated with the incoming call to a default speaker if the controller is unable to determine which of the microphones is closest to the user&#39;s mouth. 
     In one embodiment, the default speaker comprises the speaker at the wireless communication device. In another embodiment, the default speaker comprises the speaker at the corresponding headset. 
     In one embodiment, the controller is further configured to enable both of the microphones responsive to receiving user input to accept incoming call. 
     In one embodiment, the controller is further configured to poll both of the microphones to detect audible sound, and individually measure the audio reception qualities at both of the microphones based on the audible sound detected at both microphones. 
     The present invention also provides a method of routing audio signals associated with an incoming call received at the wireless communication device. In this embodiment, the wireless communication device, which is configured to communicate with a corresponding headset, measures an audio reception quality for a microphone at the wireless communication device and measures an audio reception quality for a microphone at the corresponding headset. Based on the measured audio reception qualities, the wireless communication device routes the audio signals associated with the incoming call either to a speaker at the wireless communication device, or to a speaker at the headset. 
     In one embodiment, the method further comprises determining which of the microphones is positioned closest to a user&#39;s mouth based on the measured audio reception qualities, and routing the audio signals associated with the incoming call to the speaker associated with the microphone that is closest to the user&#39;s mouth. 
     In one embodiment, the audio signals associated with the incoming call are routed to the speaker at the wireless communication device if the microphone at the wireless communication device is closer to the user&#39;s mouth than the microphone at the headset. 
     In one embodiment, the audio signals associated with the incoming call are routed to the speaker at the headset if the microphone at the headset is closer to the user&#39;s mouth than the microphone at the wireless communication device. 
     In one embodiment, the audio signals associated with the incoming call are routed to a default speaker if the wireless communication device is unable to determine which of the microphones is closest to the user&#39;s mouth. 
     In one embodiment, the default speaker comprises the speaker at the wireless communication device. 
     In one embodiment, the default speaker comprises the speaker at the corresponding headset. 
     In one embodiment, the method further comprises enabling both of the microphones to detect audible sound responsive to receiving user input to accept incoming call. 
     In one embodiment, the method further comprises polling both of the microphones to detect the audible sound, and individually measuring the audio reception qualities at both of the microphones based on the audible sound detected at both microphones. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a wireless communication device communicating with a headset according to one embodiment of the present invention. 
         FIG. 2  is a block diagram illustrating some of the component parts of a headset communicating with a wireless communication device configured according to one embodiment of the present invention. 
         FIG. 3  is a flow diagram illustrating a method performed by a controller in a user&#39;s wireless communication device according to one embodiment of the present invention. 
         FIG. 4  is a flow diagram illustrating a method performed by a controller in a user&#39;s wireless communication device according to another embodiment of the present invention. 
         FIG. 5  is a perspective view of a computing device communicating with a headset according to one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention provides a wireless communication device configured to selectively route audio signals associated with an incoming call to one of a plurality of speakers based on the placement of a microphone relative to a user&#39;s mouth. In one embodiment, the wireless communication device is paired with a wireless headset, such as a Bluetooth® headset, for example. Both the wireless communication device and the headset have respective microphones and speakers. 
     According to the present invention, a controller at the wireless communication device enables both microphones upon detecting that a user will accept an incoming call. The controller then polls both microphones to determine which of the microphones detects a user utterance (e.g., such as when the user says “Hello” to greet the calling party). Based on audio reception qualities measured at each microphone, the controller determines which of the microphones is closest to the user&#39;s mouth. The controller then routes the incoming audio signals to a speaker associated with the microphone that is determined to be closest to the user&#39;s mouth. 
     Turning now to the drawings,  FIG. 1  is a perspective view illustrating a wireless communication device configured according to one embodiment of the present invention. As seen in  FIG. 1 , the wireless communication device comprises a cellular telephone  10  and is paired with a peripheral device comprising a wireless headset  30 . However, as seen in more detail later, the present invention is suitable for use in other communications devices, such as satellite telephones, Personal Digital Assistants (PDAs), and computing devices such as laptop and notebook computers. 
     Cellular telephone  10  and headset  30  communicate with each other via a well-known short-range wireless protocol, such as the Bluetooth® protocol, for example. Initially, the cellular telephone  10  and headset  30  execute a procedure to pair with each other and establish a short-range communication link between them. That procedure is well-known to those of ordinary skill in the art and not germane to the present invention. Therefore, it is not discussed in detail herein. It is sufficient to understand that, once paired, headset  30  converts signals received at its microphone into signals compatible with a short-range wireless protocol and transmits the converted signals to the cellular telephone  10 . Headset  30  also converts wireless signals received from the cellular telephone  10  to signals compatible with a speaker in headset  30 . 
       FIG. 2  is a block diagram illustrating some of the components of a cellular telephone  10  configured according to one embodiment of the present invention as well as an exemplary wireless headset  30 . Beginning with the cellular telephone  10 , it comprises a controller  12 , a memory  14 , a user I/O interface  16 , audio processing circuitry  18 , a cellular transceiver  20 , a short-range transceiver  22 , a speaker  24 , and a microphone  26 . Controller  12  may be, for example, one or more general purpose or special purpose microprocessors that control the operation and functions of the cellular telephone  10  in accordance with program instructions and data stored in memory  14 . In one embodiment of the present invention, the controller  12  executes a program to determine which microphone (i.e., a microphone at the cellular telephone  10  or a microphone at the headset  30 ) is nearest the user&#39;s mouth. Based on that determination, controller  12  will route the audio signals associated with an incoming call (e.g., the signals carrying the voice of the remote party) to a speaker associated with that microphone. 
     Memory  14  represents the entire hierarchy of memory in cellular telephone  10 , and may include both random access memory (RAM) and read-only memory (ROM). Memory  14  stores the program instructions and data required for controlling the operation and functionality of cellular telephone  10 . In one embodiment of the present invention, memory  14  stores the instructions and data required by controller  12  for routing the audio signals of incoming calls based on the location of a microphone relative to the user&#39;s mouth. 
     The user interface  16  enables a user to input information into cellular telephone  10  and includes devices and controls that facilitate such interaction. Typically, the user interface  16  includes a display (e.g., an LCD or touch-sensitive display) that allows the user to view information such as dialed digits, images, call status, menu options, and other service information. The user interface  16  also includes a keypad that allows the user to enter digits and other alpha-numeric input, as well as an integrated microphone  26  and an integrated speaker  24 . Microphone  26  converts speech into electrical audio signals for processing by audio processing circuit  18 , and speaker  24  converts the audio signals provided by audio processing circuit  18  into audible sounds for rendering to the user. 
     Cellular transceiver  20  is a fully functional cellular radio transceiver for transmitting signals to and receiving signals from a base station or other access node in a wireless communications network. Those skilled in the art will appreciate that cellular transceiver  20  may implement any one of a variety of communication standards including, but not limited to, the standards known as the Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), Universal Mobile Telecommunication System (UMTS), TIA/EIA-136, cdmaOne (IS-95B), cdma2000, and Wideband CDMA (W-CDMA). 
     Cellular telephone  10  also includes a short-range wireless transceiver, such as a Bluetooth® transceiver  22 . As is known in the art, Bluetooth® is a universal radio interface that enables two or more wireless devices to communicate wirelessly via short-range ad hoc networks. Bluetooth® generally uses a polling based communication infrastructure to transmit and receive digital data between the wireless devices. In the present invention, the Bluetooth® transceiver  22  establishes a short-range communications link with a corresponding short-range transceiver associated with headset  30 . Digital signals carrying voice and/or control signals are communicated between the cellular telephone  10  and headset  30  via the short-range communications link. 
     The headset  30  comprises a controller  31 , a short-range transceiver such as a Bluetooth® transceiver  32 , a user interface  34 , an audio processing circuit  36 , a microphone  38 , and a speaker  40 . The controller  31  controls the operation of the Bluetooth® transceiver  32  according to a desired mode of operation. The Bluetooth® transceiver  32  communicates wireless signals with the Bluetooth® transceiver  22  of cellular telephone  10 . The user interface typically comprises an on/off control button that powers-up (and down) the headset  30  responsive to the user actuating the control, but may include other controls as well. The audio processing circuitry  36  receives electrical audio signals from the microphone  38  and converts them to digital signals for the short-range transceiver  32  to transmit to the short-range transceiver  22 . The audio processing circuitry  36  also receives digital audio signals from the cellular telephone  10  via short-range transceiver  32 , and processes those signals for rendering to the user on speaker  40 . There is a wide variety of styles for headset  30 , and the present invention is not restricted to any one particular style. However, in one embodiment, the speaker  40  and the microphone  38  of headset  30  are positioned at opposite ends of a boom that fits to the user&#39;s head. 
     As previously stated, headsets such as headset  30  are often employed by many users. However, they are not optimized for every situation. For example, consider a situation where a user&#39;s cellular telephone  10  receives an incoming call. If the user has the headset  30 , the user would likely want speaker  40  of headset  30  to render the audio signals associated with the incoming call. However, if the user had misplaced the headset  30 , the user would likely want speaker  24  of cellular telephone  10  to render the audio signals associated with the incoming call. Consider also a situation where a user is listening to music when the cellular telephone  10  receives an incoming call. In these cases, the user would likely want to have the audio signals routed to speaker  40  integrated with headset  30 . 
     Therefore, depending upon the situation, the user may want to route the audio signals associated with an incoming call to a different one of the speakers  24 ,  40 . Additionally, the factors that define the situations where a user might need the audio routed to a specific one of the speakers  24 ,  40  change dramatically. Accordingly, the present invention addresses these situations by sensing which of the microphones  26  or  38  is closest to the user&#39;s mouth, and then routing the incoming audio signals to whichever speaker ( 24  or  40 ) is associated with that microphone. 
       FIG. 3  illustrates a method  50  that is performed at a user&#39;s cellular telephone  10  upon receiving an incoming call according to one embodiment of the present invention. Method  50  begins with the cellular telephone  10  receiving an incoming call from a remote party (box  52 ). Upon receiving the call, the user will generally first perform some action to accept the call, such as pressing a button on the keypad of cellular telephone  10 . In one embodiment of the present invention, the action of accepting the incoming call triggers the controller  12  at the cellular telephone  10  to begin polling both of the microphones  26 ,  38  (box  54 ). Particularly, the controller  12  will enable microphone  26  at the cellular telephone  10 , as well as the microphone  38  at the headset  30 , to detect audible sound when the user utters “Hello” or some other greeting to the remote party (box  56 ). The controller  12  will then detect which microphone  26  or  38  is nearest to the user&#39;s mouth based on this utterance. 
     There are many methods for determining the proximity of microphones  26  and  38  to the user&#39;s mouth that are suitable for use with the present invention. However, in one embodiment, one or both of the microphones will produce electrical signals based on the detected audible sound. Controller  12  will measure the audio reception qualities of these signals at each microphone  26 ,  38 . Whichever microphone is closest to the user&#39;s mouth will have the largest measured audio reception quality. A simple comparison of these levels will identify the microphone having the largest audio reception quality, and thus, the microphone that is closest to the user&#39;s mouth. Therefore, if controller  12  measures a larger audio reception quality level at microphone  26  (box  56 ), controller  12  will determine that microphone  26  is closest to the user&#39;s mouth and route the incoming audio signals to speaker  24  (box  58 ). However, if controller  12  measures a larger audio reception quality level at microphone  38 , controller  12  will determine that the microphone  38  is closer to the user&#39;s mouth, and therefore, route the incoming audio signals to speaker  40  of headset  30  via the short-range communication link (box  60 ). If the controller  12  is unable determine which of the microphones  26 ,  38  is closest to the user&#39;s mouth (e.g., both microphones have the same measured audio reception levels, or have none at all), the controller  12  will simply route the incoming audio signals to whichever one of the speakers  24 ,  40  is the default speaker. 
     The default speaker may be either of the speakers  24 ,  40 , and may be predefined as such by the manufacturer, or user-defined and stored in a configuration file in memory. In this embodiment, speaker  40  is indicated as being the default speaker. Therefore, if controller  12  is unable to determine which of the microphones is closest to the user&#39;s mouth, controller  12  routes the audio signals of the incoming call to the speaker  40  disposed in the headset  30  (box  60 ). 
     It should be noted that method  50  is performed when the user presses a button on the keypad, or activates some other control on cellular telephone  10 . This would presume, for example, a situation wherein the user had misplaced the headset  30  or did not want to use the headset  30  to converse with the remote party. If the user pressed a button on headset  30  to answer the call, the controller  12  would not poll the microphones  26 ,  38  as previously described, but instead, would assume that the user is wearing the headset  30  and automatically route the incoming audio signals to speaker  40 . 
     Additionally, the present invention is designed to judiciously draw on the power resources of both the cellular telephone  10  and the headset  30 . Although the controller  12  enables both microphones  26 ,  38  to poll for a user utterance, they are enabled and polled only for a short time. For example, polling of both microphones  26 ,  38  would occur only for the amount of time it would usually take the user say “Hello” or utter some other greeting after pushing an answer button on the keypad (e.g., 2 seconds). If the controller  12  does not detect audible sound within that time limit, the controller  12  would send the incoming audio signals to the default speaker. 
     In another embodiment of the present invention, the controller  12  may be configured automatically direct the incoming audio signals to a pre-selected one of the speakers  24 ,  40 , and then change the routing only if a change is needed.  FIG. 4  is a flow diagram illustrating one such method  70  performed by the controller  12  at the cellular telephone  10 . As above, method  70  begins with the user&#39;s cellular telephone  10  receiving an incoming call indication from the wireless communication network (box  72 ). Upon receiving the incoming call indication, the controller  12  automatically routes the incoming audio signals to the speaker  40  in the headset  30  (box  74 ). Thus, controller  12  may operate based on the assumption that the user is wearing the headset  30 . The controller  12  then enables both microphones  26 ,  38  and begins to poll to detect a user utterance such as “Hello” (box  76 ). Based on the measured audio reception quality levels associated with the detected utterance, the controller  12  will determine which microphone (i.e., microphone  26  or microphone  38 ) is closest to the user&#39;s mouth (box  78 ). 
     As above, the controller  12  may, for example, measure the audio reception quality levels for each microphone  26 ,  38  based on the audible sound detected at each microphone  26 ,  38 . The controller  12  can then compare the two levels to determine which microphone  26 ,  38  has the larger audio reception quality level, and thus, is closest to the user&#39;s mouth. If the controller detects that the microphone  38  of headset  30  is closest to the user&#39;s mouth (i.e., microphone  38  has the larger level), the controller  12  would do nothing as the audio signals are already being routed to speaker  40  at the headset (box  78 ). Additionally, if the controller  12  cannot determine which microphone  26 ,  38  is closest, controller  12  routes the audio signals to the speaker  40  at headset  30  by default. Otherwise, if controller  12  determines that microphone  26  at cellular telephone  10  has the larger level, controller  12  would cease routing the incoming audio signals to the headset  30 , and begin routing the incoming audio signals to speaker  24  at the cellular telephone  10  (box  80 ). 
     The present invention may, of course, be carried out in other ways than those specifically set forth herein without departing from essential characteristics of the invention. For example, the previous embodiments described the present invention in the context of receiving a cellular telephone call from a remote party via a Base Station (BS) a wireless communication network. However, the present invention is not so limited. As used herein, the term “incoming call” is meant to define an incoming communication that will cause the party receiving the call to respond via voice. Thus, as used herein, an “incoming call” includes, but is not limited to, incoming cellular voice calls, satellite calls, and Voice over IP (VOIP) telephony and/or video calls, such as video conferencing calls and those supported by Skype®. 
       FIG. 5 , for example, illustrates one such embodiment wherein the user having headset  30  is engaged in a VOIP video call with a remote party. As seen in  FIG. 5 , the user has a personal computing device  90  capable of executing VOIP software applications such as Skype®. In addition to the microphone  38  and speaker  40  that is integrated with headset  30 , the computing device  90  also includes a integrated microphone  92  and a pair of speakers  94   a ,  94   b . In this embodiment, computing device  90  also includes an integrated video camera  96  capable of capturing the user&#39;s image. 
     The computing device  90 , as is known in the art, is communicatively connected to a private or public IP communication network, such as the Internet, for example. The connection may be wireless via a home wireless router, for example, or cable-based via an Ethernet network. In operation, when the user accepts an incoming call via Skype®, the computing device  90  will display the remote party&#39;s received video image on the display of computing device  90 . The camera  96  will also capture the user&#39;s video image and sent it to the remote party for display. Additionally, a controller  100  at the computing device  90  will perform the previously described method to determine whether microphone  38  or microphone  92  is closest to the user&#39;s mouth. For example, controller  100  could generate control signals to enable both microphones  38  and  92  to listen for the user&#39;s voice when the user accepts the incoming call. If, based on an analysis of the audio reception quality levels measured at the microphones  38  and/or  92 , the controller  100  determines that microphone  92  is closest to the user&#39;s mouth, controller  100  will send the incoming audio signals to the speakers  94   a ,  94   b  for rendering to the user. However, if the analysis reveals that the microphone  38  is closest to the user&#39;s mouth, controller  100  will route the incoming audio signals to the speaker  40  that is integrated with the headset  30  via a short-range transceiver  98  (e.g., a Bluetooth® interface) as stated above. 
     Therefore, the present embodiments are to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.