Patent ID: 6496581
Filing Date: 2002-12-17
Classification: G10L,H04M,H04R

Abstract:
In a communication system comprising:a first acoustic zone; a second acoustic zone; a first microphone at said first zone; a first loudspeaker at said first zone; a second microphone at said second zone and having an output supplied to said first loudspeaker such that a first person at said first zone can hear the speech of a second person at said second zone as transmitted by said second microphone and said first loudspeaker; a second loudspeaker at said second zone and having an input supplied from said first microphone such that said second person at said second zone can hear the speech of said first person at said first zone as transmitted by said first microphone and said second loudspeaker; a first model canceling the speech of said second person in the output of said first microphone otherwise present due to electrical transmission from said second microphone to said first loudspeaker and broadcast by said first loudspeaker to said first microphone, the cancellation of the speech of said second person in the output of said first microphone preventing rebroadcast thereof by said second loudspeaker; a second model canceling the speech of said first person in the output of said second microphone otherwise present due to electrical transmission from said first microphone to said second loudspeaker and broadcast by said second loudspeaker to said second microphone, the cancellation of the speech of said first person in the output of said second microphone preventing rebroadcast thereof by said first loudspeaker; the improvement comprising:a third model canceling the speech of said first person in the output of said first microphone otherwise present due to acoustic transmission from said second loudspeaker in said second zone to said first microphone in said first zone; a fourth model canceling the speech of said second person in the output of said second microphone otherwise due to acoustic transmission from said first loudspeaker in said first zone to said second microphone in said second zone.