Patent ID: 6577731
Filing Date: 2003-06-10
Classification: H03H

Abstract:
A multi-channel echo canceling apparatus suitable in a system having a plurality of received signals and a single or plural transmission signals, wherein echoes are removed by subtracting replicas from mixed signals containing a plurality of echoes and said transmission signals, said echoes being caused by said plurality of received signals propagating in a spatial acoustic paths or caused by crosstalks on transmission lines, said replicas corresponding to said plurality of echoes created by plural adaptive filters which receives said plurality of received signals, comprising:a plurality of adaptive filters each respectively corresponding to said spatial acoustic path or to said crosstalk path between channels, said adaptive filters creating said replicas in response to the same received signal as the signal supplied to a corresponding path; a non-linear processing circuit for implementing a non-linear process for said plurality of received signals to generate a plurality of non-linear received signals; a pre-processing circuit for filtering one of said plurality of non-linear received signals to generate a processed signal, time-multiplexing said processed signal and said selected non-linear received signal to be filtered, and then supplying the multiplexed signal as the new received signal to said plurality of adaptive filters and a plurality of subtracters for subtracting said created replicas from said mixed signals; whereby said plurality of filters are controlled to minimize the outputs of said plurality of subtracters.