Patent ID: 7330738

Claim:
An apparatus for canceling an echo signal in a mobile terminal of a mobile communication system, the apparatus comprising: a double talk detector (DTD) for receiving an error signal including a background noise signal and a residual echo signal as a first signal, outputting the first signal as it is during a double talk, and outputting the first signal and a second signal made up of a background noise signal and a residual echo signal during a non-double talk; an Auto-Regressive (AR) analysis and inverse filtering unit for receiving the second signal from the DTD, and whitening the second signal; a pitch analysis and inverse filtering unit for receiving the whitened signal, and canceling a pitch value remaining therein by performing pitch analysis and inverse filtering on the whitened signal; and a noise canceller for receiving the pitch-cancelled whitened signal and the first signal output from the DTD, and canceling a residual echo signal and a background noise signal from the first signal using the pitch-cancelled whitened signal.