US 2004/0057574 A1 · Suppression of echo signals and the like

Abstract

In a microphone signal, the signal component corresponding to, e.g., echo is suppressed using an echo control scheme that estimates the spectral envelope of the echo signal, without having to estimate the waveform for the echo signal. In one embodiment, the input signal (to be applied to a loudspeaker) and the microphone signal are spectrally decomposed into multiple subbands, where echo suppression processing is independently performed on each subband. The echo control of the present invention can be implemented with substantially reduced (1) computational complexity and (2) phase sensitivity, as compared to traditional acoustic echo cancellation, in which the waveform for the echo signal is estimated.

Claims18

Dependent claims

A method for processing audio signals, comprising the steps of:

(a) receiving an input signal, wherein the input signal is applied to a speaker;
(b) receiving a microphone signal generated by a microphone;
(c) estimating the spectral envelope of the input signal;
(d) estimating the spectral envelope of the microphone signal;
(e) applying the estimated input signal envelope to a filter to generate an estimate of the spectral envelope of a signal component in the microphone signal, wherein the signal component corresponds to sound generated by the speaker in response to the input signal and picked up by the microphone;
and
(f) suppressing the signal component in the microphone signal based on the estimated signal component envelope and the estimated microphone signal envelope to generate an output signal.

4 more elements

An apparatus for processing audio signals, comprising:

(a) a first operator configured to estimate the spectral envelope of an input signal, wherein the input signal is also applied to a speaker;
(b) a second operator configured to estimate the spectral envelope of a microphone signal generated by a microphone;
(c) an estimation filter configured to estimate, based on the estimated input signal envelope power, the spectral envelope of a signal component in the microphone signal, wherein the signal component corresponds to sound generated by the speaker in response to the input signal and picked up by the microphone;
and
(d) a suppression module configured to suppress the signal component in the microphone signal based on the estimated component signal envelope and the estimated microphone signal envelope to generate an output signal.

2 more elements

Dependencies are inferred from the claim text.

Suppression of echo signals and the like

Life of this patent

Suppression of echo signals and the like

Life of this patent

Abstract

Claims18