公开(公告)号：US08194852B2

公开(公告)日：2012-06-05

申请号：US11955862

申请日：2007-12-13

申请人： Markus Buck ,  Tim Haulick ,  Martin Rössler ,  Gerhard Uwe Schmidt ,  Walter Schnug

发明人： Markus Buck ,  Tim Haulick ,  Martin Rössler ,  Gerhard Uwe Schmidt ,  Walter Schnug

IPC分类号： H04M9/08

CPC分类号： H04M9/082

摘要： An echo reduction system includes a signal analysis filter that converts an input into sub-band signals. A signal down-sampling circuit down-samples the sub-band signals at a first down-sampling rate. An echo analysis filter converts a loudspeaker signal into echo sub-band signal that are further processed by an echo down-sampling circuit. The circuit down-samples the echo sub-band signals at a second down-sampling rate to generate down-sampled echo sub-band signals. An echo compensation filter folds the down-sampled echo sub-band signals with an estimated impulse response of a loudspeaker-room-input system. A second echo down-sampling circuit down-samples the folded down-sampled echo sub-band signals at a third down-sampling rate to generate estimated echo sub-band signals. The first down-sampling rate is equal to the product of the second and third down-sampling rates.

摘要翻译： 回波减少系统包括将输入转换为子带信号的信号分析滤波器。 信号下采样电路以第一下采样率对子带信号进行下采样。 回波分析滤波器将扬声器信号转换成由回波下采样电路进一步处理的回波子带信号。 电路以第二次下采样率对回波子带信号进行下采样以产生下采样的回波子带信号。 回波补偿滤波器用扬声器室输入系统的估计的脉冲响应折叠下采样的回波子带信号。 第二回波下采样电路以三次下采样率对折叠的下采样回波子带信号进行下采样，以产生估计的回波子带信号。 第一个下采样率等于第二次和第三次下采样率的乘积。