METHOD AND CIRCUIT FOR REMOVING SOUND ECHO

摘要

PURPOSE: A method and circuit for removing sound echo is provided to remove sound echo using a bidirectional sound card and a central processing unit of PC and to improve an echo removing performance and a tracking performance. CONSTITUTION: The first analysis filter bank(201) analyzes a speaker signal(x(n)) based on each band, and the second analysis filter bank(102) analyzes a microphone input signal(d(n)) based on each band. In M echo remove blocks, if an echo cancellation part(212) removes noise from an estimated echo signal(Xk(n)) of a specific band of the first analysis filter bank and a noise cancellation part(211) removes noise from a microphone input signal(Dk(n)) of a specific band of the second analysis filter bank, a sum part(218) outputs a remaining echo signal(ek(n)) of an echo-free component by subtracting an output signal of the echo cancellation part from an output signal of the noise cancellation part. A synthesis filter bank(203) adds output signals of the echo remove blocks to output a noise-free sound signal(e(n)).