Presented is a method and associated system for suppression of linear and nonlinear echo. The method includes dividing an input signal into several frequency bands in each of a several of time frames. The input signal may include an echo signal. The method further includes multiplying the input signal in each of the several frequency bands by a corresponding echo suppression signal. Calculating the corresponding echo suppression signal may include estimating a power of the echo signal in a particular frequency band as a sum of several component echo powers, each of the several component echo powers due to an excitation from a far-end signal in a corresponding one of the several frequency bands. Calculating the corresponding echo suppression signal may further include subtracting the power of the echo signal in the particular frequency band from a power of the input signal in the particular frequency band.

Example techniques involve noise-robust acoustic echo cancellation. An example implementation may involve causing one or more speakers of the playback device to play back audio content and while the audio content is playing back, capturing, via the one or more microphones, audio within an acoustic environment that includes the audio playback. The example implementation may involve determining measured and reference signals in the STFT domain. During each n.sup.th iteration of an acoustic echo canceller (AEC): the implementation may involve determining a frame of an output signal by generating a frame of a model signal by passing a frame of the reference signal through an instance of an adaptive filter and then redacting the n.sup.th frame of the model signal from an n.sup.th frame of the measured signal. The implementation may further involve determining an instance of the adaptive filter for a next iteration of the AEC.

In-car communication and hands-free talking with good sound quality are realized. An echo cancelation apparatus (4) is for use in a vehicle in which microphones (M1, M2) and loudspeakers (S1, S2) are disposed in acoustic regions (100, 200). A loudspeaker (S1) and a microphone (M1) are disposed in a first acoustic region (100), and a loudspeaker (S2) and a microphone (M2) are disposed in a second acoustic region (200). An acoustic signal picked up by the microphone (M1) disposed in the first acoustic region (100) is emitted from the loudspeaker (S2) disposed in the second acoustic region (200). An acoustic signal picked up by the microphone (M2) disposed in the second acoustic region (200) is emitted from the loudspeaker (S1) disposed in the first acoustic region (100). The microphone (M1) is designed to hardly collect a sound emitted from the loudspeaker (S2).

An illustrative controller includes: a transmitter to drive the acoustic transducer to generate acoustic bursts; a receiver to sense a response of the acoustic transducer to echoes; and a processing circuit coupled to the transmitter and to the receiver, the processing circuit configured to convert said received response into output data by: correlating said response to a driving signal to obtain a correlation response; distinguishing peak areas from non-peak areas in said correlation response; deriving a noise level in a portion of said correlation response based on the non-peak areas within said portion; calculating a signal to noise ratio (SNR) for a peak signal within the portion as a ratio of a peak value for the peak signal to the noise level in said portion of said correlation response; and accepting the peak signal as an echo only if the SNR for said peak signal exceeds a predetermined threshold.

There is provided a voice output apparatus for providing a high-quality sound to an eardrum of a user. The voice output apparatus includes a first voice output unit outputting a voice to an ear canal of a user based on an output voice signal, a first noise acquirer arranged to face outward from a body of the user and captures a mixed voice including first external noise arriving from an outside of the user to output a mixed voice signal, an echo canceler cancelling an influence, on the first external noise, of a leaked voice output from the first voice output unit and leaking to the outside of the user, and a noise canceler generating a first external noise signal corresponding to the first external noise, and processing, using the first external noise signal, an input voice signal input from the outside to generate the output voice signal.

A noise canceling adaptive filter outputs, from a front seat speaker, a noise canceling sound generated by applying a transfer function X(z) adapted by an adaptive operation using an output of a front seat microphone as an error to an output sound of a sound source apparatus. An output of the front seat microphone is added to an output of an audio feedback canceling filter by a second adder, added to an output sound of the sound source apparatus by a third adder, and output from a rear seat speaker. The audio feedback canceling filter applies a transfer function X′(z) and a transfer function C^(z) on an output of the second adder and outputs a resultant. The transfer function C^(z) corresponds to a transfer function C(z) from the front seat speaker to the front seat microphone. In synchronization control, the transfer function X(z) is set as the transfer function X′(z).

A system for dynamically controlling an echo canceler includes a processor programmed to receive audio data from an audio sensor, to determine a present type of noise in the received audio data, based on the present type of noise, to determine a number of taps to be removed from an echo canceler, and to execute the echo canceler with a reduced number of taps based on the number of taps to be removed.

A method reduces echo in a hearing instrument. A first input transducer generates a first input signal from ambient sound. A communication unit receives an external input signal from an external device. The first input signal and the external input signal are used to generate an output signal. The output signal is used in a first filter to generate a compensation signal for reducing echo and/or acoustic feedback. The first input signal and the compensation signal are used to generate an error signal. Filter coefficients of the first filter and/or a comparison of the error signal with the compensation signal and/or with the first input signal are/is used to generate a control variable. The control variable is taken as a basis for applying a second filter for rejecting a residual echo or a residual feedback to an intermediate signal derived from the input signal, and a transmission signal is generated.

An acoustic echo cancellation unit includes: an audio processor configured to receive a multichannel audio signal and including: a first stage which is configured to process the multichannel audio signal to obtain a first set of spatial audio components; and a second stage which is configured to process the first set of spatial audio components to obtain a second set of spatial audio components; an echo cancellation processor configured to perform echo cancellation by use of the first set of spatial audio components or a deviated version of the first set of spatial audio components as reference signal.

In-car communication and hands-free talking with good sound quality are realized. An echo cancelation apparatus (4) is for use in a vehicle in which microphones (M1, M2) and loudspeakers (S1, S2) are disposed in acoustic regions (100, 200). A loudspeaker (S1) and a microphone (M1) are disposed in a first acoustic region (100), and a loudspeaker (S2) and a microphone (M2) are disposed in a second acoustic region (200). An acoustic signal picked up by the microphone (M1) disposed in the first acoustic region (100) is emitted from the loudspeaker (S2) disposed in the second acoustic region (200). An acoustic signal picked up by the microphone (M2) disposed in the second acoustic region (200) is emitted from the loudspeaker (S1) disposed in the first acoustic region (100). The microphone (M1) is designed to hardly collect a sound emitted from the loudspeaker (S2).