Patent ID: 8189765

Claim:
A multichannel echo canceller provided in a first location and used in an acoustic system in which acoustic signals are transmitted between the first location and a second location in an interactive manner, wherein a first acoustic signal emitted from one or more sound sources present in the first location is detected by a plurality of microphones provided in the first location, wherein a second acoustic signal emitted from one or more sound sources present at the second location is detected by a plurality of microphones provided in the second location, wherein an acoustic signal transmitted from the first location to the second location is reproduced by a plurality of loudspeakers provided in the second location, and wherein an acoustic signal transmitted from the second location to the first location is reproduced by a plurality of loudspeakers provided in the first location, the multichannel echo canceller comprising: an obtaining section that obtains (i) detection signals detected by the plurality of microphones provided in the first location and (ii) loudspeaker input signals transmitted from the second location to the first location, the detection signals detected by the plurality of microphones provided in the first location including (i) the first acoustic signal and (ii) reproduced acoustic signals obtained by the loudspeaker input signals being reproduced by the plurality of loudspeakers provided in the first location; and an echo cancellation section that (i) multiplies a separation matrix and an input vector including the detection signals and the loudspeaker input signals, (ii) separates (a) the first acoustic signal, which is included in the detection signals, from (b) the second acoustic signal, which is included in the reproduced acoustic signals included in the detection signals, and (iii) outputs the separated first acoustic signal, wherein the separation matrix separates (i) the first acoustic signal, which is included in the detection signals, from (ii) the second acoustic signal, which is included in the reproduced acoustic signals included in the detection signals, the separation matrix including: a first submatrix including a plurality of matrix elements concerning each transfer characteristic from the plurality of loudspeakers provided in the first location to the plurality of microphones provided in the first location; a second submatrix including a plurality of matrix elements concerning each transfer characteristic from the one or more sound sources present in the second location to the plurality of microphones provided in the second location; a third submatrix including a plurality of matrix elements that separate, from the detection signals, the second acoustic signal, which is included in the reproduced acoustic signals included in the detection signals; and a fourth submatrix including a plurality of matrix elements concerning each transfer characteristic from the one or more sound sources present in the first location to the plurality of microphones provided in the first location.