An electronic device according to an embodiment includes a speaker capable of outputting a sound wave, a sensor capable of acquiring an optical signal related to blood flow at a measured part of a user, and a controller configured to measure blood flow information of the measured part based on the optical signal. The controller estimates a sleep state of the user based on the blood flow information and controls, based on the sleep state, a sound wave outputted from the speaker.

An electronic device includes a speaker, a sensor, a communication circuit, a processor, and a memory to store instructions. The instructions, when executed by the processor, cause a wireless audio device to, while outputting a signal for reducing an external sound through the speaker, identify, using the communication circuit, an external electronic device, identify, using the sensor, a conversation responsive to a location of the external electronic device satisfying a specified condition, responsive to identifying the conversation, stop an output of the signal for reducing the external sound for a first period of time, and responsive to identifying a specified keyword included in the conversation, prolong stopping the output of the signal for reducing the external sound for a second period of time.

The present invention provides an improved noise separation hybrid type ANC system, which includes a reference audio receiving device, an error audio receiving device, an audio output device, and an audio processing device. The audio processing device includes a feed-forward noise cancellation filter module, a feedback noise cancellation filter module, a mixer, a noise shaper, a first infinite impulse response filter, and a second infinite impulse response filter. When the noise bandwidth detector detects irregular noise, it adjusts the coefficient of the first infinite impulse response filter to set it as a low-pass filter; when regular noise is detected, the coefficient of the second infinite impulse response filter is adjusted to set it as a band-pass filter.

An active noise control device includes a control signal generating unit including a first adaptive filter configured to generate a control signal by performing a filtering process on a reference signal corresponding to noise, an identifying unit configured to identify a peak frequency in an impedance frequency characteristic of an actuator, a peak frequency storage unit configured to store an initial peak frequency of the actuator, a first determination unit configured to determine whether or not a difference between the peak frequency currently identified and the initial peak frequency is greater than or equal to a threshold value, and a control unit configured to change a characteristic of the control signal generated by the control signal generating unit when the first determination unit determines that the difference is greater than or equal to the threshold value.

An active noise control device includes a first adaptive filter configured to generate a control signal by performing a filtering process on a reference signal corresponding to noise, and a first filter coefficient updating unit configured to update a filter coefficient of the first adaptive filter based on based on the reference signal and an added error signal acquired by adding a first error signal acquired by detecting residual noise by a first microphone and a second error signal acquired by detecting residual noise by a second microphone.

Sound reduction includes producing an error signal representative of sound present in a target space, producing a reference signal corresponding to undesired sound present in the target space, and producing, based on the reference signal and the error signal a cancelling output signal representative of the undesired sound present in the target space. The method further includes producing, based on the cancelling output signal, sound to destructively interfere with the undesired sound present in the target space, and limiting the amplitude or power of at least one of the reference signal, the error signal and the cancelling output signal if a first condition is met, the at least one signal under examination is at least one of the reference signal, the error signal and the cancelling output signal, and fully or partially suspending the active noise controller update mechanism if a second condition is met.

Method for automatably or automated tuning at least one operational parameter of an engine-order-cancellation (“EOC”) apparatus, the EOC apparatus being operable on the basis of a number of operational parameters, comprising the steps of: providing a defined tuning rule for automatably or automated tuning at least one operational parameter of an EOC apparatus, and automatably or automated tuning the at least one operational parameter of the EOC apparatus on basis of the provided tuning rule.

[Problem] To provide a technology capable of comfortably enjoying audio content via multiple channels even in a noisy environment. [Solution] A wireless terminal 3 is disposed at a listening point of a multi-channel audio device 1. The multi-channel audio device 1 plays a multi-channel audio signal as audio playback signals of a plurality of channels, and outputs an audio playback signal for each channel from the corresponding speaker 2, and the wireless terminal 3 collects the environmental sound at the listening point, and transmits the sound collection signal to the multi-channel audio device 1. The multi-channel audio device 1 identifies, as a noise component, the difference between the sound collection signal received from the wireless terminal 3 and the audio playback signals of the plurality of channels output from the plurality of speakers, generates a noise canceling signal with the opposite phase to the noise component, and outputs the noise canceling signal from any speaker 2.

A method performed by a headset that includes a speaker and an in-ear microphone, the method includes performing a calibration on the headset to obtain a baseline measurement; using, while the headset is being worn by a user, an audio signal to drive the speaker that is arranged to project sound into a canal of a user's ear; capturing as a microphone signal, from the in-ear microphone of the headset, sound from within the canal of the user's ear; determining a parameter associated with the user's ear based at least on the captured microphone signal and the baseline measurement; and transmitting a notification related to one or more characteristics of one or more hearing elements of the user's ear based on the parameter.

Provided is a signal processing device that performs noise canceling by combining a feedforward method and a feedback method. A signal processing device includes: a correlation calculation unit that calculates a correlation between a first sound pickup signal by a first microphone installed outside a predetermined region and a second sound pickup signal by a second microphone installed in the predetermined region; a determination unit that determines the correlation; and a control unit that performs control based on a result of the determination. The control unit controls execution of signal processing for generating a cancellation signal to be output within the predetermined region from the first sound pickup signal and the second sound pickup signal or output of the cancellation signal.