Abstract:
Systems and methods for active noise cancellation are provided. An example method includes receiving at least two reference signals associated with at least two reference positions. Each of the at least two reference signals includes at least one captured acoustic sound representing an unwanted noise. The reference signals are filtered by individual filters to obtain filtered signals. The filtered signals are combined to obtain a feedforward signal. The feedforward signal is played back to reduce the unwanted noise at a pre-determined space location. The individual filters are determined based on linear combinations of at least two transfer functions. Each of the at least two transfer functions is associated with one of the reference positions. In certain embodiments, the at least two reference signals are captured by at least two feedforward microphones.
Abstract:
An improved user experience is provided for passengers of a transportation vessel, such as an airplane. A passengers experience is enhanced by allowing the passenger to enjoy media provided by an entertainment device without ambient noise. When the passenger requests accesses to a media item through the entertainment device, a microphone in the entertainment system generates an ambient noise signal based on captured ambient noise. A noise cancellation device generates a predictive noise cancelling signal based on the ambient noise signal. To generate the predictive noise cancelling signal, the noise cancellation device inverts the ambient noise signal and applies a predictive phase shift to the signal based on an estimated distance between the microphone and the passengers ears. The noise cancelling signal is mixed with audio of the media item.
Abstract:
A noise cancellation filter structure for a noise cancellation enabled audio device, in particular headphone (HP), comprises a noise input for receiving a noise signal (N0) and a filter output for providing a filter output signal (OUT). A first noise filter (CF) produces a first filter signal by filtering the noise signal (N0) and a second noise filter (AF) produces a second filter signal by filtering the noise signal (N0). The second noise filter (AF) has a frequency response with a non-minimum-phase, in particular maximum-phase. A combiner (CMB) is configured to provide the filter output signal (OUT) based on a linear combination of the first filter signal and the second filter signal.
Abstract:
A method of sound management of a space which is defined by at least one barrier element; said method comprising reducing or eliminating the ambient sound as it travels through the barrier element by applying a signal to the barrier element.
Abstract:
The disclosure relates to combined active noise cancellation and noise compensation in a headphone. An audio processing device includes a selector and a noise compensation unit. The selector can select one of a plurality of first transfer functions based on at least one feature of at least one of an external noise and a content audio signal representing a sound to be reproduced through the headphone. The noise compensation unit can compute a second audio signal by applying the selected first transfer function to a first audio signal, and derive gains for the noise compensation at least based on the second audio signal. The at least one feature can be used to distinguish at least two of the first transfer functions. Each of the first transfer functions can transform the first audio signal to the second audio signal which is assumed as representing a version of the sound represented by the first audio signal, which arrives at an eardrum of a listener wearing the headphone. The first audio signal is one of a noise signal representing the external noise and the content audio signal.
Abstract:
The invention relates to a dynamic hearing protection device to be worn completely in a user's ear canal (10), comprising: a lateral part (32, 36) and a medial part (34, 36) flexibly connected in such a manner that the lateral part and the medial part can bend relative to each other so as to follow the shape of the ear canal, wherein the medial part is to be inserted at least in part into the bony part (16) of the ear canal and comprises an acoustic damping element (70) at its periphery which is adapted to touch the wall (18) of the bony part of the ear canal for attenuating sound impinging on the hearing protection device, wherein the lateral part includes a microphone arrangement (42) including a microphone port (41) for capturing audio signals from ambient sound, wherein the microphone port is to be located at least 1 mm inside the ear canal, wherein the hearing protection device includes a non-replaceable battery (48) and an audio signal processing unit (44) for processing the audio signals captured by the microphone assembly, wherein the medial part includes a loudspeaker (52) for stimulating the user's hearing according to the processed audio signals, and wherein the audio signal processing unit is adapted to provide at least for an attenuation mode in which the gain applied to the audio signals is less than the mechanical acoustic damping provided by the hearing protection device when worn in the ear canal.
Abstract:
Disclosed is a system, method, and computer program product for canceling ambient noise in a portable mobile communications device 100 that is coupled with a standard non-noise canceling headset assembly 105, 150. The portable mobile communications device 100 receives detected ambient noise from the headset assembly microphone 115, 155 and creates a noise canceling ambient noise sound wave that is 180° out of phase with the ambient noise sound wave 330, 440. The noise canceling ambient noise sound wave is then combined 340, 440 with an intended sound wave such as music or speech. The combined noise canceling ambient noise sound wave and intended sound wave are then forwarded 350, 450 to the headset assembly such that the noise canceling ambient noise sound wave negates the ambient noise present at the headset assembly during playback of the intended sound wave. Noise canceling can be achieved using hardware filters 230 or via a noise canceling software application 240 within the portable mobile communications device 100.
Abstract:
An apparatus and method provides control over the relative level of audio and background sound for an audio device such as a headset or headphones. An input sound transducer (312) can be provided and configured to convert ambient acoustical pressure into an electrical background signal representing the background sound. Noise cancellation circuitry create a cancellation signal that is the inverse of the electrical background signal. A summing component is coupled to the noise cancellation component and combines the cancellation signal with an audio signal representing audio program content and provides the combined electrical signal to an output sound transducer (332) . A controller is coupled to the noise cancellation component and is configured to control the level of a cancellation signal relative to the audio signal, thereby controlling the mix of cancellation signal and audio signal reaching the output sound transducer (332) .