Abstract:
The subject matter provides a method that enable detecting if a party engaged into a tele-conference call is attempting to engage into conversation while a microphone is in a mute mode. The method provides receiving of a signal. The signal is then analyzed to determining if a party is attempting to engage into conversation. If it is determined that the party is attempting to engage in the conversation then an alarm is transmitted indicating the mode of operation of the microphone. The transmitted alarm may be an audio alert or a visual alert.

Description:
FIELD OF THE INVENTION 
     The present invention relates to telecommunications in general, and, more particularly, to detecting the mute status of a microphone. 
     BACKGROUND OF THE INVENTION 
     When people are engaged in a conference call, it is common for the people at one end of the call to mute the microphone. But the manual muting and un-muting of the microphone has disadvantages, and, therefore, the need exists for improvements in muting and un-muting a microphone. 
     SUMMARY OF THE INVENTION 
     The present invention enables a telecommunications system to afford a muting function without some of the costs and disadvantages for doing so in the prior art. For example, the illustrative embodiment detects when a user is speaking into a microphone that is muted, and, therefore, alerts the user to the fact and automatically un-mutes the microphone. 
     The illustrative embodiment detects that the user is speaking into the microphone in two ways. First, the illustrative embodiment comprises a proximity sensor which detects the proximity of the user to the microphone. Second, the illustrative embodiment analyzes the user&#39;s voice and, based on the user&#39;s intonation, infers that the user is speaking into the microphone and not merely to another person in his or her vicinity. In this way, the illustrative embodiment provides a muting function that avoids some of the costs and disadvantages with muting functions in the prior art. 
     The illustrative embodiment comprises: receiving a speech signal of a user of a microphone; and transmitting an alarm when: (i) the microphone is muted, and (ii) the intonation of the speech signal indicates that the user is speaking into the microphone. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts a schematic diagram of the salient portion of telecommunications system  100  in accordance with the illustrative embodiment. 
         FIG. 2  depicts a flowchart of the salient tasks performed in accordance with the illustrative embodiment. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  depicts a schematic diagram of the salient portion of telecommunications system  100  in accordance with the illustrative embodiment. Telecommunications system  100  comprises: user  101 , telecommunications terminal  110 , and processor  120 , interconnected as shown. 
     Telecommunications terminal  110  comprises: microphone  111 , mute button  112 , proximity sensor  114 , speaker  114 , and visual alarm  115 . In accordance with the illustrative embodiment, microphone  111 , mute button  112 , and proximity sensor  113  have a distinct connection with processor  120 , but it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention in which microphone  111 , mute button  112 , and proximity sensor  113  share a single connection. In accordance with the illustrative embodiment, processor  120  has a distinct connection with speaker  114  and visual alarm  115 , but it will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention in which speaker  114  and visual alarm share a single connection. 
     Microphone  111  is an electro-acoustic transducer that receives an acoustic speech signal from user  101  and converts it into an electrical signal for processor  120 . In accordance with the illustrative embodiment, microphone  111  converts acoustic signals into electrical signals for processor  120  when microphone  111  is both muted and when it is not muted. It will be clear to those skilled in the art how to make microphone  111 . 
     Mute Button  112  is hardware for enabling user  101  to mute microphone  111 . It will be clear to those skilled in the art how to make and use mute button  112 . 
     Proximity sensor  114  is an infra-red sensor that is designed to detect the body heat of user  101  when user  101  is speaking into microphone  111  and to transmit a proximity signal indicating such to processor  120 . It will be clear to those skilled in the art, after reading this disclosure, how to make and use alternative embodiments of the present invention in which proximity sensor  113  uses one or a combination of technologies for detecting when user  101  is speaking into microphone  111 . For example and without limitation, microphone  111  can also use ultra-sonics, acoustics, radio, etc. to detect when user  101  is speaking into microphone  111 . It will be clear to those skilled in the art how to make and use proximity sensor  113 . 
     Speaker  114  is an electro-acoustic transducer for outputting sound and audible alarms from processor. It will be clear to those skilled in the art how to make and use speaker  114 . 
     Visual alarm  115  is hardware for alerting user  101  to the fact that user  101  is speaking into microphone  111  when microphone  111  is muted. It will be clear to those skilled in the art how to make and use visual alarm  115 . 
     Processor  120  is hardware and software for processing the signals from microphone  111 , proximity sensor  113  and for producing the signals for speaker  114  and visual alarm  115  as described below with respect to  FIG. 2 . 
       FIG. 2  depicts a flowchart of the salient tasks performed in accordance with the illustrative embodiment. 
     At task  201 , processor  120  receives a mute signal from mute button  112  and mutes microphone  111 . 
     At task  202 , processor  120  receives a speech signal from microphone  111  or a proximity signal from proximity sensor  113  or a combination both the speech signal and the proximity signal. 
     At task  203 , processor  120  determines if the proximity signal from proximity sensor  113  suggests that user  101  is speaking into microphone  111 . If the answer is yes, then control passes to task  206 ; otherwise control returns to task  204 . In an embodiment, proximity of user  101  may be determined by examining the speech signal. The inventors of this subject matter have determined that speech characteristics of the speech signal vary subject to proximity of user  101  from microphone  111 . For example, prosody of the speech signal change with proximity of user  101  and microphone  111 , by examining changes in prosody, proximity of user  101  may be determined. If the proximity obtained from such examination suggests that the user is speaking into microphone  111 , then the control passes to task  206 ; otherwise control returns to task  204 . 
     At task  204 , processor  120  analyzes the speech signal to assess user  101 &#39;s intonation. The inventors of this subject matter have also recognized that in addition to determine proximity of user  101  and microphone  111 , speech characteristics of the speech signal may also be used to further confirm whether user  101  is speaking into microphone  111 . In an embodiment the speech signal may be analyzed to extract a level of intonation or a text string or both from the speech signal. In another embodiment, a voice activity detector is employed in processor  120 . The voice activity detector monitors energy levels of the speech signal and background noise. 
     In a further embodiment, the speech signal is analyzed against user  101 &#39;s acoustic and vocal patterns received during an un-muted mode of microphone  111 . For practicing this embodiment, processor  120  is configured to receive samples of acoustic and vocal patterns during un-muted mode of microphone  111  and generate a voice print according to the samples. The speech signal may be analyzed against the voice print. 
     At task  205 , processor  120  determines whether the user  101 &#39;s intonation suggests that user  101  is speaking into microphone  111 . By comparing the level of intonation with a predetermined threshold processor  120  determines if user  101  is speaking into microphone  111 . In an embodiment, processor  120  examines the text string to determine if user  101  is speaking into microphone  111 . An example of the text string may include “can you hear me” or “are you there”, etc. In another embodiment the voice activity detector determines whether user  101  is speaking in microphone  111  by comparing the energy levels of the speech signal and background noise against a threshold energy level. In a further embodiment, results from the analysis of the voice print and the speech signal are used for determining if user  101  is speaking into microphone  111 . If processor  120  at task  204  determines that user  101  is speaking into microphone  111  then, control passes to task  206 ; otherwise control returns to task  201 . 
     At task  206 , processor  120  transmits (i) an alarm signal to speaker  114  and visual alarm  115  alerting user  101  to the fact that microphone  111  is muted. 
     At task  207 , processor  120  un-mutes microphone  111 . 
     It is to be understood that the disclosure teaches just one example of the illustrative embodiment and that many variations of the invention can easily be devised by those skilled in the art after reading this disclosure and that the scope of the present invention is to be determined by the following claims.