A system configured to perform distributed echo cancellation processing to attenuate feedback echo from occurring when two devices are acoustically coupled during a communication session. To reduce the feedback echo, one of the devices is configured as a hub device and receives microphone signals, synchronizes the microphone signals, and generates a mixed microphone signal. To enable distributed echo cancellation, the system includes bidirectional feedback link(s) between the hub device and each device synchronized with the hub device. For example, a first bidirectional feedback link sends a microphone signal from a second device to the hub device and sends the mixed microphone signal from the hub device to the second device, which the second device uses to perform echo cancellation. In addition, a second bidirectional feedback link sends a playback signal from the hub device to the second device and sends the output of echo cancellation back to the hub device.

A system configured to perform distributed echo cancellation processing to attenuate feedback echo from occurring when two devices are acoustically coupled during a communication session. To reduce the feedback echo, one of the devices is configured as a hub device and receives microphone signals, synchronizes the microphone signals, and generates a mixed microphone signal. To enable distributed echo cancellation, the system includes bidirectional feedback link(s) between the hub device and each device synchronized with the hub device. For example, a first bidirectional feedback link sends a microphone signal from a second device to the hub device and sends the mixed microphone signal from the hub device to the second device, which the second device uses to perform echo cancellation. In addition, a second bidirectional feedback link sends a playback signal from the hub device to the second device and sends the output of echo cancellation back to the hub device.

A signal processing device includes: a processing unit configured to collect, through a microphone, a mixed sound signal as a mixed sound of a speaker reproduction signal and a target signal, input a first suppression signal resulting from suppression of the speaker reproduction signal from the mixed sound signal by linear processing, the speaker reproduction signal, and the mixed sound signal collected through the microphone, and output a second suppression signal resulting from further suppression of the speaker reproduction signal from the first suppression signal by non-linear processing.

A signal processing device includes: a processing unit configured to collect, through a microphone, a mixed sound signal as a mixed sound of a speaker reproduction signal and a target signal, input a first suppression signal resulting from suppression of the speaker reproduction signal from the mixed sound signal by linear processing, the speaker reproduction signal, and the mixed sound signal collected through the microphone, and output a second suppression signal resulting from further suppression of the speaker reproduction signal from the first suppression signal by non-linear processing.

To provide improved feedback reduction in hearing assistance devices, technical solutions described herein include remeasuring a feedback path and updating adaptive feedback cancellation parameters whenever a user receives and plays an audio stream signal. When the user converts the audio stream signal into an acoustic audio signal using a speaker within the hearing assistance device, a feedback portion of the acoustic audio signal may be fed back into the microphone of the hearing assistance device. The hearing assistance device can then compare the feedback portion to the received audio stream signal, and that comparison can be used to update adaptive feedback cancellation parameters within the hearing assistance device. When the hearing assistance device receives an acoustic audio input at the microphone, it may amplify that input and apply the received acoustic audio input based on the updated adaptive feedback cancellation parameters to reduce or minimize feedback.

A public address system includes audio inputs from a moderator/presenter and from one or more participants. In an embodiment, the moderator speaks first and then selects participants to speak, utilizing audio captured by participant devices. A central signal processor is configured to receive the audio inputs and to utilize a configured acoustic model to provide for acoustic echo cancellation (AEC) and feedback control (FBC) during various phases of a presentation or conference. Audio signals from the presenter and/or participants, that have been processed to remove echo, are utilized as reference signals during various phases of the audio presentation that utilize the acoustic model for either AEC or FBC. The system utilizes the knowledge that the best learning occurs during the far talking state to learn the echo path in the canceler mode (AEC) vs. the feedback mode (FBC), which usually can only train in a double-talking mode.

A public address system includes audio inputs from a moderator/presenter and from one or more participants. In an embodiment, the moderator speaks first and then selects participants to speak, utilizing audio captured by participant devices. A central signal processor is configured to receive the audio inputs and to utilize a configured acoustic model to provide for acoustic echo cancellation (AEC) and feedback control (FBC) during various phases of a presentation or conference. Audio signals from the presenter and/or participants, that have been processed to remove echo, are utilized as reference signals during various phases of the audio presentation that utilize the acoustic model for either AEC or FBC. The system utilizes the knowledge that the best learning occurs during the far talking state to learn the echo path in the canceler mode (AEC) vs. the feedback mode (FBC), which usually can only train in a double-talking mode.

A noise estimation method including steps of generating gap confidence values in response to microphone output and playback signals, and using the gap confidence values to generate an estimate of background noise in a playback environment. Each gap confidence value is indicative of confidence of presence of a gap at a corresponding time in the playback signal, and may be a combination of candidate noise estimates weighted by the gap confidence values. Generation of the candidate noise estimates may but need not include performance of echo cancellation. Optionally, noise compensation is performed on an audio input signal using the generated background noise estimate. Other aspects are systems configured to perform any embodiment of the noise estimation method.

A noise estimation method including steps of generating gap confidence values in response to microphone output and playback signals, and using the gap confidence values to generate an estimate of background noise in a playback environment. Each gap confidence value is indicative of confidence of presence of a gap at a corresponding time in the playback signal, and may be a combination of candidate noise estimates weighted by the gap confidence values. Generation of the candidate noise estimates may but need not include performance of echo cancellation. Optionally, noise compensation is performed on an audio input signal using the generated background noise estimate. Other aspects are systems configured to perform any embodiment of the noise estimation method.

A plurality of microphone signals can be captured with a plurality of microphones of the device. One or more echo dominant audio signals can be determined based on a pick-up beam directed towards one or more speakers of a playback device. Sound that is emitted from the one or more speakers and sensed by the plurality of microphones can be removed from plurality of microphone signals, by using the one or more echo dominant audio signals as a reference, resulting in clean audio.