A Fourier Transform (FT) module configured to determine amplitudes of acceleration at predetermined orders, respectively, by performing a FT on a plurality of values of acceleration associated with a wheel. An order module is configured to identify one of the predetermined orders where one of the amplitudes is greater than a predetermined value and to, based on the one of the amplitudes and a rotational speed of the wheel, determine an order of a frequency corresponding to the rotational speed of the wheel. A sound control module is configured to set characteristics for outputting sound at the order of the frequency corresponding to the rotational speed of the wheel. An audio driver module is configured to, based on the characteristics, apply power to a speaker within a passenger cabin of the vehicle at the order of the frequency corresponding to the rotational speed of the wheel.

A noise and vibration sensor arrangement which is configured to operate with a road noise control system, and includes four acceleration sensors each configured to generate at least one output signal representative of at least one of accelerations, motions and vibrations that act on the respective acceleration sensor. The arrangement includes a vehicle subframe structure having a shape that is axisymmetric to a first axis and that has a maximum extent along a second axis. The first and the second axis are perpendicular. The four sensors are attached to the subframe structure at positions that correspond to four corners of a virtual rectangle. The virtual rectangle has two perpendicular centerlines, one of the centerlines being in line with the first axis of the subframe structure. The extent of the virtual rectangle along the other centerline is less than fifty percent of the subframe structure's maximum extent along the second axis.

Noise and vibration sensing includes generating with an acceleration sensor a sense signal representative of the acceleration that acts on the acceleration sensor, and processing the sense signal to provide a processed sense signal having an adjustable signal bandwidth and an adjustable signal dynamic. The signal bandwidth extends between a lowest frequency and a highest frequency of the sense signal, and the signal dynamic is the ratio between a maximum amplitude of the sense signal and an output noise floor generated by the acceleration sensor. Noise and vibration sensing further includes adjusting the signal bandwidth and the signal dynamic in accordance with a control signal so that the signal bandwidth increases when the signal dynamic decreases and vice versa.

An active road-noise control system and method include using a sensor arrangement to generate a first sense signal representative of at least one acceleration, motion and/or vibration that occurs at a first position on a vehicle body and a second sense signal representative of sound that occurs at a second position within the vehicle body; they also provide a noise-reducing signal by processing the sense signals according to a first or a second mode of operation. They include the generation of noise-reducing sound within the vehicle body at the second position from the noise reducing signal and the operational state of the sensor arrangement; the first sense signal and the second sense signal are processed in the first mode when the sensor arrangement is in a proper operational state and in the second mode when a malfunction of the sensor arrangement has been detected.

Embodiments of the present disclosure provide a noise reduction method, the method includes: obtaining an acceleration signal of a mobile terminal when an audio output device is in a working state; determining, according to the acceleration signal, a vibration waveform of the mobile terminal when the mobile terminal vibrates; inverting the determined vibration waveform to obtain a noise reduction signal; and superimposing the noise reduction signal onto to-be-output audio of the audio output device. Therefore, noise generated by skeleton vibration is diminished or eliminated, so as to improve an effect of listening, by a person, to audio.

Exemplary road and engine noise control systems and methods include directly picking up road noise from a structural element of a vehicle to generate a first sense signal representative of the road noise, directly picking up engine noise from an engine of the vehicle to generate a second sense signal representative of the engine noise, and combining the first sense signal and the second sense signal to provide a combination signal representing the combination of the first sense signal and the second sense signal. The systems and methods further include broadband active noise control filtering to generate a filtered combination signal from the combination signal, converting the filtered combination signal provided by the active noise control filtering into anti-noise and radiating the anti-noise to a listening position in an interior of the vehicle. The filtered combination signal is configured so that the anti-noise reduces the noise at the listening position.

An active noise control system for reducing the sound pressure level in one or more head areas of one or more seats in the interior of an aircraft fuselage includes multiple accelerometers mounted outside of the aircraft fuselage at or near the mounts of the aircraft's propulsion system. One or more loudspeakers are mounted at the seat and are responsible for the reduction of noise at its head area. The accelerometers continuously measure multiple reference signals during operation of the aircraft and report to a controller that continuously calculates the reported noise signals in the head areas based on the measured reference signals and its counter signals, which equal the amplitude but having opposite phase of the calculated arriving noise signals in each head area. The controller operates one or more actuator systems for continuously generating the counter signals.

An open-ear device performs active noise cancellation (ANC) for a user. A sensor located outside an ear of a user which does not occlude an ear canal of the ear and measures vibrational data indicative of a sound pressure level at a location outside the ear, or a level of pinna vibration of the user. A prediction pipeline generates a prediction of sound pressure within the ear canal using an individualized model, taking into account the measured vibrational data and the unique geometric shape of the user's head and pinna. This sound pressure prediction is used to generate audio instructions for rendering playback at an noise cancellation source, such as a bone conduction transducer and/or cartilage transducer, to perform ANC for the user by cancelling at least portion of the sound received at the ear canal.

A noise and vibration sensor arrangement which is configured to operate with a road noise control system, and includes four acceleration sensors each configured to generate at least one output signal representative of at least one of accelerations, motions and vibrations that act on the respective acceleration sensor. The arrangement includes a vehicle subframe structure having a shape that is axisymmetric to a first axis and that has a maximum extent along a second axis. The first and the second axis are perpendicular. The four sensors are attached to the subframe structure at positions that correspond to four corners of a virtual rectangle. The virtual rectangle has two perpendicular centerlines, one of the centerlines being in line with the first axis of the subframe structure. The extent of the virtual rectangle along the other centerline is less than fifty percent of the subframe structure's maximum extent along the second axis.

A method for feedforward noise cancellation in an enclosed space within a structure is provided. The method comprises placing a microphone array inside an inner surface of the enclosed space and conducting modal testing on an outside surface of the enclosed space, wherein the modal testing comprises multiple incoherent noise sources corresponding to locations of microphones in the microphone array. Noise generated by the modal testing is processed to create a number of acoustic mathematical models of the enclosed space. In response to incoherent noise within the enclosed space, a noise canceling signal is generated according to an output of the mathematical models.