Patent attributes
A multi-channel acoustic echo cancellation (AEC) system that includes a residual echo suppressor (RES) that dynamically controls an amount of attenuation to reduce distortion of local speech during double-talk conditions. The RES determines when double-talk conditions are present based on an echo return loss enhancement (ERLE) value. When the ERLE value is above a first threshold value but below a second threshold value, the RES reduces an amount of attenuation applied while generating an RES mask to pass local speech without distortion. When the ERLE value is below the first threshold value or above the second threshold value, the RES applies full attenuation while generating the RES mask in order to suppress a residual echo signal. To further improve RES processing, the RES may apply smoothing across time, smoothing across frequencies, or apply extra echo suppression processing to further attenuate the residual echo signal.
