Noise abatement within a signal stream containing unwanted signal referred to as noise is performed by acquiring a digitized noise signal and using a digital processor circuit to subdivide the acquired noise signal into different frequency band segments and thereby generate a plurality of segmented noise signals. Then individually for each segmented noise signal, the processor shifts in time the segmented noise signal by an amount dependent on a selected frequency of the segmented noise signal to produce a plurality of shifted segmented noise signals. The precise time shift applied to each noise segment considers the frequency content of the segment and the system processing time. Individually for each segmented noise signal, amplitude scaling is applied. The shifted and amplitude-scaled segmented noise signals are then combined to form a composite anti-noise signal which is output into the signal stream to abate the noise through destructive interference.

Various technologies described herein pertain to active noise cancellation in the interior of a vehicle. In exemplary embodiments, a microphone mounted on the vehicle outputs an audio signal indicative of noise emitted by a noise source. A computing system of the vehicle determines a position of the noise source based upon sensor signals output by sensors mounted on the vehicle. The computing system further determines a position of a passenger in the vehicle based upon a sensor mounted inside the vehicle. The computing system generates a complementary signal that is configured to attenuate the noise based upon the audio signal, the position of the noise source, and the position of the passenger. The complementary signal is then output by way of a speaker in the interior of the vehicle.

An in-ear active noise reduction earphone includes a housing, and the housing includes a rear chamber and a front chamber, and the housing is laterally provided with a sound generating unit separating the rear chamber from the front chamber; the rear chamber is located at a top of the housing, a feedforward microphone is installed inside the rear chamber, the front chamber is located at a bottom of the housing, and a feedback microphone is installed inside the front chamber; and the front chamber includes a first front chamber and a second front chamber, and the feedback microphone is installed inside the second front chamber.

Various technologies described herein pertain to active noise cancellation in the interior of a vehicle. In exemplary embodiments, a microphone mounted on the vehicle outputs an audio signal indicative of noise emitted by a noise source. A computing system of the vehicle determines a position of the noise source based upon sensor signals output by sensors mounted on the vehicle. The computing system further determines a position of a passenger in the vehicle based upon a sensor mounted inside the vehicle. The computing system generates a complementary signal that is configured to attenuate the noise based upon the audio signal, the position of the noise source, and the position of the passenger. The complementary signal is then output by way of a speaker in the interior of the vehicle.

A headphone has a driver, an internal microphone, an accelerometer, and an external microphone. An audio processor analyzes signals to detect wind noise. Gain of lower frequencies is reduced relative to higher frequencies, in a first filter that is operating on an audio signal from the external microphone in a feedforward path, responsive to detecting increased wind noise. A second filter in an audio signal feedback path may be adjusted to compensate for the gain change in the first filter that may mitigate occlusion effect. Outputs of the feedforward path in the feedback path are combined to produce an audio signal for the driver. The driver produces sound in the aural canal that has transparency with reduced wind noise, relative to sound external to the headphone. Other aspects are also described and claimed.

Audio pickup systems and methods are provided to enhance an audio signal by removing noise components related to an acoustic environment. The systems and methods receive a primary signal and one or more reference signals from various microphones. Adaptive filtering and combining minimizes an energy content of a resulting output signal, e.g., to form a substantially null output when the system is in a static acoustic environment. When the system is a playback sound source, one or more echo cancellers may contribute to removing content from the output signal. A change in the acoustic environment, such as a new sound source, causes content in the output signal until the adaptive filtering adapts to the new environment. In some examples, a desired content such as a wake-up word is detected and adaptation is stopped.

An earpiece includes a housing including a sound output channel operatively coupled to a speaker formed within the housing. An ear canal feedback channel is formed extending alongside the sound output channel and operatively coupled to a microphone formed within the housing and a DSP operatively coupled to the microphone, the DSP including a voice activity detection module to detect a microphone audio data stream and discern between host audio data stream of audio played by the speaker and external ear canal noise captured in the microphone audio data stream at the microphone at the ear canal feedback channel. An audio processor receives the detected external ear canal noise and generate audio data descriptive of an opposite waveform to the detected external ear canal noise to playback and reduce the detected external ear canal noise.

A noise reduction system for actively compensating background noise in a passenger transport area of a vehicle. The noise reduction system includes a nonlinearity filter unit having a model of a non-linear transfer function of the sound generator, wherein the nonlinearity filter unit is configured to receive the anti-noise signal and to generate a filtered anti-noise signal by applying a non-linear filter function on the anti-noise signal, which is based on the model of the non-linear transfer function in that the non-linear response of the sound generator is at least partially corrected when driven by the filtered anti-noise signal. Wherein the nonlinearity filter unit is further configured to output the filtered anti-noise signal to a sound generator.

A method for binaural synthesis of at least one virtual sound source comprises operating a first device comprising at least four physical sound sources, wherein, when the first device is used by a user, at least two physical sound sources are positioned closer to a first ear of the user than to a second ear, and at least two physical sound sources are positioned closer to the second ear than to the first ear, and wherein, for each ear, at least two physical sound sources are configured to acoustically induce natural directional pinna cues associated with different directions of sound arrival at the ear of the user. The method further comprises receiving and processing at least one audio input signal and distributing at least one processed version of the audio input signal at least between 4 kHz and 12 kHz over at least two physical sound sources for each ear.

A headphone arrangement is configured to induce natural directional pinna cues. The arrangement comprises an ear cup comprising a frame configured to at least partly encircle the ear of a user, wherein the frame is at least partially hollow. The arrangement further comprises a loudspeaker arranged within a wall of a frontal part, a rear part, an upper part, and/or a lower part of the frame, the loudspeaker comprising a membrane, a first side of the membrane facing a cavity inside the frame, and a second side of the membrane facing the outside. At least one loudspeaker is arranged at a first angle with respect to a median plane crossing a user's head midway between the user's ears such that a main direction of sound propagation is directed away from the median plane, and the second side of the membrane is directed away from the median plane.