Patent ID: 7925006
Filing Date: 2011-04-12
Classification: H04M,H04R

Abstract:
1. An echo cancel method associated to a space provided therein with a plurality of loudspeakers and at least one microphone for forming a plurality of audio transfer systems through which audio signals of multi-channels having a correlation with each other are reproduced by said respective loudspeakers and are collected by said at least one microphone, and designed for performing an echo cancellation by subtracting an echo cancel signal from the audio signals collected by the respective microphone, the method comprising: inputting a plurality of low-correlation audio signals which are obtained by suitably combining first audio signals of multi-channels and which have a lower correlation with each other than that among said first audio signals of multi-channels; generating second audio signals of multi-channels having a correlation with each other by computation based on the inputted low-correlation audio signals; feeding the generated second audio signals to the respective loudspeakers so as to reproduce audio sounds; feeding the generated second audio signals or the inputted low-correlation audio signals to filters; estimating individual transfer functions of said plurality of said audio transfer systems based on the inputted low-correlation audio signals so as to set corresponding filter characteristics; producing echo cancel signals by applying said set filter characteristics to the second audio signals; and subtracting said echo cancel signals from collected audio signals obtained by collecting the reproduced audio sounds by the at least one microphone, thereby performing the echo cancellation.