Patent ID: 8170199
Filing Date: 2012-05-01
Classification: H04M,H04R

Abstract:
1. An echo canceller for suppressing an echo produced by inputting into a microphone a voice signal being output from a speaker, comprising: detection means for detecting a deviation between a first sampling period of a digital-to-analog converter for converting a received first digital voice signal to an analog voice signal, so as to output from the speaker, and a second sampling period of an analog-to-digital converter for converting an analog voice signal being input into the microphone to a second digital voice signal; first conversion means for frequency-converting the first digital voice signal to a first frequency signal; second conversion means for converting the second digital voice signal to a second frequency signal; frequency shift means for uniformly frequency-shifting a whole frequency spectrum of the first frequency signal by a frequency width based on the deviation detected by the detection means; correlation calculation means for obtaining a correlation between the second frequency signal and the first frequency signal frequency-shifted by the frequency shift means; and echo suppression means for suppressing the echo included in the second frequency signal, based on said correlation.