A signal processing apparatus is configured to preprocess a sound wave signal and output a processed audio signal through an electromagnetic wave. The signal processing apparatus includes: a receiving unit, configured to receive at least one sound wave signal; a conversion unit, configured to convert the at least one sound wave signal to at least one audio signal; a positioning unit, configured to determine position information related to the at least one sound wave signal; a processing unit, configured to determine a sending time point of at least one audio signal based on the position information and a first time point, where the first time point is a time point at which the receiving unit receives the at least one sound wave signal; and a sending unit, configured to send the at least one audio signal through the electromagnetic wave.

This application discloses a method for reducing an occlusion effect of an earphone, and a related apparatus. The method is applied to an earphone having at least one microphone and a speaker. The method includes: detecting occurrence of at least one of the following events: a user speaks and the user is in a motion state; and triggering at least one of the following operations in response to the at least one event: processing the user's sound signal based on the at least one microphone to suppress an occlusion effect of the earphone, and playing an audio by using the speaker, to mask a sound signal in the user's auditory canal. Embodiments of this application can reduce or even eliminate the earphone occlusion effect, to improve user experience.

A vehicle that selectively provides important sound to an occupant includes: a microphone configured to receive a noise sound; a speaker; a storage configured to store a plurality of sound waveforms and a warning sound source corresponding to each sound waveform of the plurality of sound waveforms; and a controller configured to generate a noise canceling signal based on the noise sound, control the speaker to output a noise canceling sound corresponding to the noise canceling signal, compare a waveform of the noise sound with the plurality of sound waveforms when a sound pressure level of the noise sound is greater than a threshold value, and when the waveform of the noise sound matches any sound waveform of the plurality of sound waveforms, and control the speaker to play a warning sound source corresponding to the sound waveform matching the noise sound.

Methods and systems are provided for an automatic noise control system. Automatic noise control includes evaluating an amplitude of an acceleration acting on an acceleration sensor and generating a reference signal representative of the amplitude of the acceleration, the acceleration being representative of unwanted noise sound generated by a noise source, filtering the reference signal with a noise control transfer function to generate an anti-noise signal, and converting with a loudspeaker the anti-noise signal into anti-noise sound.

An earpiece of a headset uses a first signal and a second signal received from an in-ear microphone and an outside microphone, respectively, to enhance microphone signals. The in-ear microphone is positioned at a proximal side of the earpiece with respect to an ear canal of a user, and the outside microphone is positioned at a distal side of the earpiece with respect to the ear canal. A processing unit includes a filter, which digitally filters out in-ear noise from the first signal using the second signal as a reference to produce a de-noised signal to thereby enhance the microphone signals.

There are provided a control signal generation unit 120 that generates a control signal on the basis of a cosine wave signal and a sine wave signal whose frequencies are a control frequency identified according to a vibration noise source, and a correction value update unit that updates a correction value to a value for decreasing signal power of an error signal on the basis of a relationship between increase and decrease of the signal power of the error signal obtained from remaining vibration noise that remains after interference sound that is generated on the basis of the control signal and propagates through a secondary route interferes with vibration noise generated from the vibration noise source and increase and decrease of the correction value used for correction of the control frequency.

An active noise cancellation system (1) for cancelling environment noise perceived by a driver or passenger seated in a seat (3) mounted in a cabin of a vehicle, in combination with said seat, the seat comprising a seat cushion (19), a seat back (21) coupled to the seat cushion at a bottom end and extending upwards to a seat shoulder (23), and a headrest (22) coupled to the seat back, extending upwardly from the seat shoulder, the active noise cancellation system comprising an active noise cancellation circuit (ANC) (30), a plurality of microphones (10) mounted in the headrest and connected electrically to the ANC, and a plurality of speakers (16) mounted in the seat and connected electrically to the ANC circuit. The plurality of microphones comprises at least one first microphone mounted on a right side of the headrest and at least one second microphone mounted on a left side of the headrest, and the plurality of speakers comprises at least one first speaker mounted in the seat shoulder on a left side and at least one second speaker mounted in the seat shoulder on a right side, the right speaker configured to generate a noise cancellation sound from a noise signal picked up by the right microphone processed by the ANC circuit and the left speaker configured to generate a noise cancellation sound from a noise signal picked up by the left microphone processed by the ANC circuit.

The present subject matter relates to systems and methods for selectively amplifying an acoustic signal in a closed environment. In an implementation, a plurality of acoustic signals may be received from within the closed environment. Frequency ranges corresponding to each acoustic signal may be obtained and compared to determine presence of at least one individual in the closed environment. Acoustic signals pertaining to the at least one individual may be analysed to detect occurrence of a physiological event. Based on the analysis, the acoustic signal may be recognized as a target signal, and the target signal may be amplified in the closed environment. Further, an interfering signal may be generated to cancel other acoustic signals within the closed environment.

The disclosure provides an audio processing device comprising a first filter and a second filter. The first filter is configured to generate a first filtered signal based on an error signal, the error signal representative of audible sound at a target space. The second filter is configured to generate a second filtered signal based on the error signal. An anti-noise signal is generated based on the first filtered signal and the second filtered signal, and the anti-noise signal is included in the error signal. The first filter is connected to the second filter in parallel.

The present disclosure is a noise cancellation system including: a microphone that converts a sound wave into an electrical signal; a transmission line that propagates the electrical signal from the microphone; a speaker that reproduces a sound wave from the electrical signal from the transmission line; a phase inversion circuit that is provided between the microphone and the speaker, and inverses the phase of the electrical signal; a gain adjustment circuit that is provided between the microphone and the speaker, and adjusts a gain for amplifying the electrical signal; and a delay adjustment circuit that is provided between the microphone and the speaker, and adjusts the amount of delay of the electrical signal.