Adaptive noise cancellation systems and methods include a reference sensor to sense environmental noise and generate a corresponding reference signal, an error sensor to sense noise in a noise cancellation zone and generate a corresponding error signal, a noise cancellation path including a noise cancellation filter and a variable gain component, the noise cancellation path receiving the reference signal and generating an anti-noise signal to cancel noise at an eardrum reference point, and an adaptation module to receive the reference signal and the error signal and adaptively adjust weights of the noise cancellation filter and/or the variable gain component. An adaptive gain control block updates the variable gain component. Inputs to the adaptive gain control block are conditioned using programmable filters to protect against low frequency transients and/or high frequency distractors in the environmental noise. The programmable filters are tuned to optimize cancellation at an eardrum reference point.

Noise cancellation systems and methods are provided that generate an anti-noise signal configured to destructively interfere with noise in a cancellation zone. The systems and methods receive a signal representative of the noise in the cancellation zone. The signal is analyzed to identify a frequency to be reduced in the cancellation zone, and the signal is down converted to place the identified frequency at baseband. A baseband anti-noise signal is generated based upon the down converted signal. The baseband anti-noise signal is up converted to the identified frequency to produce an anti-noise signal having components at the identified frequency, and the anti-noise signal is provided to be transduced into an acoustic signal.

An active noise control unit generates a noise canceling sound of a single frequency that cancels engine sound heard by an occupant and outputs the noise canceling sound to a speaker through an amplifier. A second harmonic detector and a third harmonic detector detect a magnitude of a harmonic component of the noise canceling sound included in sound collected by a microphone. A controller controls a frequency of the noise canceling sound generated by the active noise control unit to a fundamental frequency of the engine sound based on a rotation frequency of the engine, and in addition, causes an output level control unit to control a level of the noise canceling sound to be output to the amplifier so that the level of the noise canceling sound becomes higher when the magnitude of the harmonic component exceeds a predetermined threshold value.

For example, an apparatus may include an input to receive input information including a Heating, Ventilation and Air Conditioning (HVAC) input including HVAC configuration information corresponding to a configuration of an operation of an HVAC system of a vehicle; a plurality of noise inputs representing acoustic noise at a plurality of noise sensing locations; and a plurality of residual-noise inputs representing acoustic residual-noise at a plurality of residual-noise sensing locations within at least one sound control zone in the vehicle; a controller configured to determine a sound control pattern to control sound within the at least one sound control zone in the vehicle, the controller configured to determine the sound control pattern based on the HVAC input, the plurality of noise inputs and the plurality of residual-noise inputs; and an output to output the sound control pattern to a plurality of acoustic transducers.

A loudspeaker arrangement includes an air-tight, rigid, thermo-conductive enclosure (103) with an aperture (115) and an outer surface, and a loudspeaker (101) air-tightly mounted in the aperture (115) to form a locked acoustic volume within the enclosure (103). The arrangement further includes a multiplicity of thermo-conductive fins (112) attached to or integrated in the enclosure (103) at the outer surface thereof. The multiplicity of fins (112) is distributed over the outer surface of the enclosure (103).

A method of identifying a system, the method comprising: obtaining an indication of background noise present at the system; generating a probe signal based on the indication; applying the probe signal to the system; estimating a response of the system to the probe signal; and identifying the system based on the measured response and the probe signal, wherein the probe signal comprises a whitening component configured to whiten noise in the estimated response due to the background noise present at the system.

For example, an apparatus may include an input to receive input information including a Heating, Ventilation and Air Conditioning (HVAC) input including HVAC configuration information corresponding to a configuration of an operation of an HVAC system of a vehicle; a plurality of noise inputs representing acoustic noise at a plurality of noise sensing locations; and a plurality of residual-noise inputs representing acoustic residual-noise at a plurality of residual-noise sensing locations within at least one sound control zone in the vehicle; a controller configured to determine a sound control pattern to control sound within the at least one sound control zone in the vehicle, the controller configured to determine the sound control pattern based on the HVAC input, the plurality of noise inputs and the plurality of residual-noise inputs; and an output to output the sound control pattern to a plurality of acoustic transducers.

An active noise canceling apparatus using a motor may include a reference sensor configured for detecting a noise source of the vehicle; an error sensor configured for detecting information related to internal noise of the vehicle; an adaptive control circuit configured of adjusting a filter value for reducing the internal noise of the vehicle on the basis of detecting signals from the reference sensor and the error sensor, and generating a current instruction for driving the motor by applying the adjusted filter value; a motor controller configured for controlling driving of the motor to follow the current instruction; and a radiation sound generator engaged to the motor and generating sound for offsetting the internal sound using vibration generated according to the driving of the motor.

A noise suppressor includes a memory; and a processor coupled to the memory, the processor is configured to: acquire a noise signal in a vicinity of a head region of an occupant seated in a vehicle seat; generate a control sound having an opposite phase to the acquired noise signal; acquire a sound signal having a predetermined frequency that is different from the noise signal; and output, as an output sound signal, the acquired sound signal in combination with the generated control sound.

In one embodiment, a computer-program product embodied in a non-transitory computer readable medium that is programmed for performing active vibration cancellation (AVC) in a moving vessel is provided. The computer-program product includes instructions to receive a first signal indicative of vibrations that are exhibited on at least one passenger in a cabin of the moving vessel and to determine a resonant frequency of the vibrations that are exhibited on the at least one passenger based on the first signal. The computer-program product further includes instructions to generate a first anti-wave signal based on the resonant frequency and to drive at least one haptic actuator that is positioned proximate to the at least one passenger in the cabin with the first anti-wave signal to minimize motion sickness for the at least one passenger caused by the vibrations that are exhibited on the at least one passenger in the vessel.