Patent Abstract:
An induction-type loopset is provided that is connectable to a wireless device. The loopset contains a first coil electromagnetically coupled to a t-coil hearing aid and an impedance-matching device coupled to the first coil. The impedance-matching device is responsive to an audio signal from the wireless device. The induction-type loopset is powered from the power source of the wireless device. The power source is responsive to an activation state of the wireless device.

Full Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to providing a power source for an inductive loopset. More particularly, this invention relates to providing operating power to an inductive loopset using battery power provided by a wireless phone. 
     2. Description of Related Art 
     Telecoil (T-coil) hearing aid users commonly experience interference from the high-frequency electromagnetic signal emitted by wireless phones when the phone is placed in close proximity to the t-coil. The interference—a “buzz” or “hum” in the hearing aid—makes the use of wireless phone handsets difficult. To assist these users, audio induction systems were created. Audio induction systems operate using the principles of electro-magnetics. When an electrical current is amplified and passed through a wire loop, an electromagnetic field is generated around the wire that varies in direct proportion to the amplitude and frequency of the signal. If another wire (or wire loop) is placed in proximity to this field, an identical current will be passed (induced) to the wire. Finally, the current representative of the original audio signal is amplified for hearing. 
     Personal loopsets were created to apply the audio induction principle to wireless devices so that the wireless phone could be used with t-coil hearing aids. As shown in  FIG. 1 , the coil  40  of loopset  5  is worn around the user&#39;s neck. The coil  40  is coupled to an impedence-matching device  33  inside the housing  30 . The impedance-matching device  33  receives a voice signal from the wireless phone  10 , transmits the corresponding electromagnetic field to the coil  40 , and ultimately to a hearing aid placed in proximity to the coil  40 . 
     Current designs of loopsets use small cell batteries to power the electronics of the loopset. As shown  FIG. 2 , the battery  34  provides operating power to the loopset  5  when the terminal  41  has been inserted into the jack  42 . The insertion of the terminal  41  completes an electrical path, which allows the loopset  5  to produce an induction current. 
     The current designs have inherent problems that, if removed, would make major strides in the loopset technology. First, in order for the loopset  5  to operate, the terminal  41  must be plugged into the jack  42 . Using this approach, a hearing impaired user is almost forced to constantly wear the loopset to hear an incoming call to the wireless phone  10 . This means that the coil  40  is constantly emitting an electromagnetic magnetic field if the loopset is being worn and the battery power is constantly being depleted. This leads to inconvenience and a short battery life. Thus, a user is forced to replace the battery often. However, if a user decides to keep the loopset in a pocket or a bag, to conserve battery power, a user must fumble to put the loopset on if a call is received while the loopset is not being worn. 
     Thus, the inventors have discerned that there is a need to address the above-mentioned problems by providing a loopset that is more user friendly than current configurations and overcomes the problems identified above. 
     SUMMARY OF THE INVENTION 
     As outlined above, conventional loopsets are limited in their user friendliness. Thus, it is an object of the present invention to provide a user-friendly loopset for the hearing impaired by powering the loopset using a readily available power source without causing significant reduction in the life of the power source. 
     This invention provides an induction-type loopset for the hearing impaired configured to connect to a wireless device. The loopset comprises a first coil configured to be electromagnetically coupled to a t-coil hearing aid and an impedance-matching device coupled to the first coil. The impedance-matching device is responsive to an audio signal from a wireless device and the induction-type loopset is selectively powered from the power source of the wireless device. 
     This invention also provides a power source for the wireless device that selectively supplies power to the loopset in response to an activation state of the wireless device. 
     This invention separately provides a method for selectively supplying power to an induction-type loopset for the hearing impaired by connecting a wireless device to the loopset and selectively supplying power to the loopset from the wireless device depending on an activation state of the wireless device. The method further provides a method for detecting a change in the activation state of the wireless device and controlling a switch based on the detecting step. 
     Thus, this invention provides systems and methods for powering a loopset from the power source of a wireless phone. The systems and methods of this invention take advantage of many of the features already present in wireless phone configurations. Examples of such features include battery cycle down modes and “sleep” modes of the attached wireless phone. 
     In the various exemplary embodiments according to this invention, power provided to the loopset is controlled by the microcontroller in the wireless phone. This method allows the loopset to take advantage of automatic power-down and battery save features provided in the wireless phone. In addition, by using the microcontroller within the wireless phone, the configuration of the loopset is simplified. 
     In the various exemplary embodiments according to this invention, a switch controlling power to the loopset is activated and switched using signals from the microcontroller of the wireless phone. The pattern of control of the loopset is essentially the same as the pattern of the operating modes in the wireless phone. For example, when the wireless phone is in a standby mode, no power is provided to the loopset. However, when a call is received, a signal is sent from the microprocessor of the wireless phone to activate the loopset. The loopset is then returned to the standby/off state once the call has ended and the wireless phone again enters the standby mode. 
     These and other features and advantages of this invention are described in or apparent from the following detailed description of the apparatus/systems and methods according to this invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various exemplary embodiments of this invention will be described in detail, with reference to the following figures, wherein: 
         FIG. 1  illustrates the configuration of an induction type loopset for a wireless phone; 
         FIG. 2  illustrates a conventional loopset configuration powered by a small battery; 
         FIG. 3  is a block diagram showing the configuration of a conventional loopset powered by a small battery; 
         FIG. 4  is a block diagram showing a first exemplary embodiment of a loopset according to this invention; 
         FIG. 5  is a block diagram showing a second exemplary embodiment of a loopset according to this invention; 
         FIG. 6  is a flowchart outlining an exemplary embodiment of a method for providing power to a loopset using the power source of a wireless phone when the wireless phone receives an incoming call; and 
         FIG. 7  is a flowchart outlining an exemplary embodiment of a method for providing power to a loopset using the power source of a wireless phone when a user initializes an outgoing call. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       FIGS. 4–7  illustrate various embodiments of the present invention. Similar reference numbers are used for similar elements between each of the  FIGS. 1–7 . In this detailed description, the term “wireless phone” is used as an exemplary embodiment only. The term is intended to apply to any wireless device that has voice capability, including but not limited to devices from Research In Motion®, PALM®, Microsoft®, Dell® and cordless land-line telephones. 
       FIG. 3  illustrates the configuration of a conventional loopset  5 . As shown in  FIG. 3 , the conventional system includes a coil  40 , a housing  30  and a wire  20 . The wire  20  is connected to a wireless phone that provides voice signals to the loopset  5 . The housing  30  contains a microphone  31 , a sound processor  32 , a battery source  34 , a gain amplifier  36 , an impedance-matching device  33 , and a common ground  35 . The cable  20  contains a connection to the common ground  35  of the connected wireless phone (not shown), an audio input line  21  and a microphone-out line  22 . The battery source  34  is typically a removable small battery, such as a “AAA” battery or at least one button cell. 
     The sound processor  32  can be any conventional device capable of receiving a microphone input signal from the microphone  31  and amplifying the input signal&#39;s strength to a level that is readable by the processors of the wireless phone. Carried on microphone-out line  22 , the signal output by the sound processor  32  is received by a detector circuit (not shown) within a wireless phone (not shown) for processing. During operation, the impedance-matching device  33  is excited by an audio output signal from the wireless phone. The audio output signal is passed to the loopset  10  through the audio input line  21  and through the gain amplifier  36 . The excitation of the impedance-matching device  33  outputs an electromagnetic field across the coil  40 . The output electromagnetic field is in direct proportion to the signal input from the audio input line  21 . The electromagnetic field is subsequently received by a t-coil hearing aid in proximity to the coil  40 . 
     As one can see from  FIG. 3 , the battery source  34  supplies operating power to the components contained in the housing  30 . 
     Due to the need for the hearing-impaired user to hear all portions ambient sound surrounding his environment, as well as the user produced sounds (voice, movement, etc.), this application has been described such that the sound processor  32  will combine and transmit, to the coil  40 , sounds from the microphone  31 , microphone-outline  22  and the audio-out line  21 . Should any portion of the sounds resulting from these items not be transmitted to the user, it may be difficult for the user to hear necessary information. Although it is described that these component&#39;s outputs have been combined, it should be appreciated that any combination of these sounds may be excluded from the resulting combination without departing from the scope of the invention. 
       FIG. 4  shows a first embodiment of the present invention. The loopset  100  comprises a coil  40 , a housing  130  and a wire  120 . The wire  120  is connected to the wireless phone  10  and to the housing  130 . The wireless phone  10  provides voice signals to the loopset  100 . The housing  130  contains a microphone  31 , a sound processor  32 , a gain amplifier  36 , an impedance-matching device  33 , and a common ground  35 . The cable  120  contains a common ground  35 , an audio input line  21 , a microphone-out line  22  and a power line  15 . The power line  15  is connected to switch  13  of the wireless phone and to the control function of the gain amplifier  36 . The common ground  35  connects the ground terminal of the housing  130  and the wireless phone  10 . The wireless phone  10  also contains a wireless phone battery source  12 , a control line  14  and a microcontroller  11 . Not shown in  FIG. 4  are the other conventional components of the wireless phone  10  known to those skilled in the art that are required for its operation. Those components are not necessarily relevant to the understanding and operation of this invention, thus they have not been illustrated. 
     In operation, under control of the microcontroller  11 , power is selectively supplied to the loopset  100  from the wireless phone battery source  12  across the power connection  15 . The operation of the switch  13  is a function of the operation of the relevant features of the wireless phone  10 . For example, because the loopset  100  only requires power during an incoming or out going call, when the wireless phone  10  transitions into an idle state from an operation state (i.e., the end of a call), a signal is sent from the microcontroller  11  to the switch  13  across control line  14  to open switch  13  and thereby disconnects the power to the loopset  100 . When a call is received or placed from the wireless phone  10 , as the microcontroller  11  transitions the cell phone state from the idle state to the operation state, switch  13  closes enabling power to be supplied to the loopset  100  from the cell phone battery source  12 . 
     The microcontroller  11  also controls the operation of the microphone  31  and the emission of the impedance-matching device  33 . During certain instances, the microphone  31  may not need to be active while the impedance-matching device  33  is active. For example, when a call is being placed, the microphone  31  does not need to be activated unless the call is connected. However, a user may want to hear tones emitted by the keypad of the wireless phone  10 . Table 1 illustrates an example of possible activation states of the microphone  31  and the impedance-matching device  33  of a loopset, as controlled by the microcontroller  11  of the wireless phone  10 . In the table, the “◯” indicates inactive states and “X” represent active states. 
     
       
         
               
             
               
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Mic/Coil States 
               
             
          
           
               
                   
                 Phone State 
                 Mic State 
                 Coil State 
                 Power Switch State 
               
               
                   
                   
               
               
                   
                 Idle 
                 ◯ 
                 ◯ 
                 open 
               
               
                   
                 Wake 
                 ◯ 
                 X 
                 closed 
               
               
                   
                 Receive 
                 ◯ 
                 X 
                 closed 
               
               
                   
                 Call Connected 
                 X 
                 X 
                 closed 
               
               
                   
                 SMS 
                 ◯ 
                 X 
                 closed 
               
               
                   
                   
               
             
          
         
       
     
     It should be appreciated that in a simpler configuration of this invention, the control signals from the microcontroller  11  can simply only provide a switching command to the switch  13  without providing additional commands to control the state of the microphone  31  and the coil  40 . In this configuration, the state of the microphone  31  and the coil  40  would be on/off in conjunction with the state of the switch  13 . 
     A still simpler configuration may omit the switch  13  and simply rely on power supplied directly from the wireless phone for its operation. 
       FIG. 5  illustrates a second embodiment of the claimed invention. This embodiment contains essentially the same items as shown in the first embodiment. However, the switch  16  is placed outside of the wireless phone  10  along the cable  220 . This configuration does not require modification of the wireless phone  10  itself. Therefore, the second embodiment can be used with any configuration of current wireless phones with little modification to the microcontroller  11  such that command signals may be sent across command line  14  to control the operation of the switch  16  and ultimately operation of microphone and coil states of the loopset  100 . 
       FIG. 6  is a flowchart outlining one exemplary embodiment of a method of operation of a loopset during an incoming call according to this invention. As shown in  FIG. 6 , the process begins at step S 60 , and continues to step S 61 , where an incoming call is received by the wireless device. The incoming call is received by the wireless phone in a manner that is well known in the art or yet to be developed. Next, in step S 62 , the wireless phone is removed from the standby mode to the operation mode or “state” consistent with Table 1 by a microcontroller of the wireless phone. The process then continues to step S 63  where the wireless phone is placed in a talk mode to establish a voice connection between the wireless phone  10  and the calling party. The process then continues to step S 64 . 
     In step S 64 , the microcontroller of the wireless phone sends a signal to switch  13  to close. Thus, power is provided from the power source of the wireless phone  10  to the connected loopset  100 . The process then continues to step S 65 , wherein the microphone  31  and the sound processor  32  are activated and the loopset  100  begins to transmit the appropriate electromagnetic field to a t-coil hearing aid in proximity to the loopset. Then control ends at step S 66 . 
       FIG. 7  is a flowchart outlining one exemplary embodiment of a method of operation of a loopset  100  during an outgoing call according to this invention. As shown in  FIG. 7 , the process begins at step S 70 , and continues to step S 71 , wherein a microcontroller within a wireless phone  10  recognizes a keypad entry from a user. This keypad entry indicates that the user is making an outgoing call. Next, in step S 72 , the wireless phone  10  is transitioned from the standby state to the operation state by the microcontroller of the wireless phone. The process then continues to step S 73  where the wireless phone is placed in a talk mode ready to respond to a voice connection established by the network between the wireless phone  10  and the called party. The process then continues to step S 74 . 
     In step S 74 , the microcontroller  11  of the wireless phone  10  sends a command to a switch to provide power from the battery of the wireless phone to the connected loopset  100 . The process then continues to step S 75 , wherein the microcontroller  11  determines if the outgoing call has connected within a predetermined amount of time. If the call connects within the predetermined time, the process continues to step S 78 ; otherwise, the process continues to step S 76 . 
     In step S 78 , the microphone  31  and the sound processor  32  are activated when the loopset  100  begins to transmit the appropriate electromagnetic field to a t-coil hearing aid in proximity to the loopset. The process then continues to step S 79  where the system monitors to determine when the call has ended. When the call has ended, the process continues to step S 80 , prior to that time the process loops back to step S 79 . In step S 80 , the microprocessor  11  deactivates the microphone  31  and the sound processor  32 . The process then continues to step S 76 . 
     In step S 76 , power is disconnected from the loopset  100  by opening switch  13  responsive to a command from microcontroller  11 . The process finally ends at step S 77 . 
     While this invention has been described in conjunction with the exemplary embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. For example, the order of some steps of operation could be re-arranged. Accordingly, the exemplary embodiments of the invention, as set forth above are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and the scope of the invention.

Technology Classification (CPC): 7