An apparatus may include a passive vibration member and an active vibration member connected to the passive vibration member and including first and second vibration portions arranged in parallel with each other. The apparatus may further include a driving apparatus configured to apply a first driving signal to the first vibration portion and a second driving signal to the second vibration portion, based on an input signal, to vibrate the first vibration portion and the second vibration portion.

The type of acoustic absorber comprises a micro-perforated plate, a cavity behind the micro-perforated plate, a slender and curved main acoustic propagation passage communicating with the cavity, and a set of acoustic filters arranged along the main acoustic propagation passage. These acoustic filters have different cut-off frequencies and are arranged in the order of the cutoff frequencies from high to low from the open end to the closed end of the main acoustic propagation passage. The acoustic filter comprises a section of the main acoustic propagation passage and at least one cavity communicating with the main acoustic propagation passage. The type of acoustic absorber is characterized by adopting a main acoustic propagation passage to provide different phase delay for a micro-perforated plate to realize that a micro-perforated plate effectively absorbs broadband acoustic waves, and by combing the close arrangement of main acoustic propagation passage to achieve the ultra-thin structure.

A method, an apparatus, and logic to post-process raw gains determined by input processing to generate post-processed gains, comprising using one or both of delta gain smoothing and decision-directed gain smoothing. The delta gain smoothing comprises applying a smoothing filter to the raw gain with a smoothing factor that depends on the gain delta: the absolute value of the difference between the raw gain for the current frame and the post-processed gain for a previous frame. The decision-directed gain smoothing comprises converting the raw gain to a signal-to-noise ratio, applying a smoothing filter with a smoothing factor to the signal-to-noise ratio to calculate a smoothed signal-to-noise ratio, and converting the smoothed signal-to-noise ratio to determine the second smoothed gain, with smoothing factor possibly dependent on the gain delta.

A method, an apparatus, and logic to post-process raw gains determined by input processing to generate post-processed gains, comprising using one or both of delta gain smoothing and decision-directed gain smoothing. The delta gain smoothing comprises applying a smoothing filter to the raw gain with a smoothing factor that depends on the gain delta: the absolute value of the difference between the raw gain for the current frame and the post-processed gain for a previous frame. The decision-directed gain smoothing comprises converting the raw gain to a signal-to-noise ratio, applying a smoothing filter with a smoothing factor to the signal-to-noise ratio to calculate a smoothed signal-to-noise ratio, and converting the smoothed signal-to-noise ratio to determine the second smoothed gain, with smoothing factor possibly dependent on the gain delta.

A whistling sound suppression method includes: obtaining an ambient audio signal, the ambient audio signal being a sound signal in a surrounding environment of an earphone; filtering the ambient audio signal according to a preset first filter group to obtain a first audio signal; obtaining an ear canal audio signal, the ear canal audio signal being a sound signal when the first audio signal propagates in an ear canal; and filtering a subsequently obtained ambient audio signal according to a preset second filter group to obtain a second audio signal in response to the ear canal audio signal meets a whistling condition.

A whistling sound suppression method includes: obtaining an ambient audio signal, the ambient audio signal being a sound signal in a surrounding environment of an earphone; filtering the ambient audio signal according to a preset first filter group to obtain a first audio signal; obtaining an ear canal audio signal, the ear canal audio signal being a sound signal when the first audio signal propagates in an ear canal; and filtering a subsequently obtained ambient audio signal according to a preset second filter group to obtain a second audio signal in response to the ear canal audio signal meets a whistling condition.

A method for audio signal noise cancellation is provided. In response to current noise cancellation coefficients being required to be updated to new noise cancellation coefficients, the digital signal processor calculates the new noise cancellation coefficients and writes the new noise cancellation coefficients into an idle storage module in the at least two storage modules, and the digital signal processor sends an update request for updating the noise cancellation coefficients to the active noise cancellation module. The update request carries position information configured to indicate a position of the storage module to which the new noise cancellation coefficients is written. The active noise cancellation module reads the new noise cancellation coefficients in the storage module indicated by the position information based on the position information carried in the update request, and performs noise cancellation processing according to the new noise cancellation coefficients after a current noise cancellation processing cycle ends.

Arrangements for communication and/or noise attenuation within an aircraft, and aircraft and methods for making aircraft including such arrangements are provided. In one example, an arrangement includes an array of first microphones cooperatively configured to be directed towards a first aircraft operator when disposed in a first cockpit seat to receive a first communication input from the first aircraft operator. An array of first speakers is cooperatively configured to be directed towards the first aircraft operator when disposed in the first cockpit seat to provide a first communication output to the first aircraft operator.

Resonating patch for acoustic treatment comprising a resonant plate, a transducer and an electrical circuit electrically connected to the transducer, the resonant plate comprising a peripheral strip extending along the perimeter of the resonant plate.

The patch comprises cutouts together defining deformable lamellae having at least one end connected to the peripheral strip.

A noise abating wall including piers with integral column members, columns each including two laterally extending wing walls, and a spandrel panel. The piers are secured in spaced ground holes with column members extending vertically from the pier securing the columns in a vertical orientation with the wing wall outer sides having a selected spacing from one wing wall of an adjacent column. The spandrel panels are wider than the selected spacing of wing walls of adjacent columns whereby the spandrel panel sides overlap the sides of adjacent wing walls. First connectors on the spandrel panel front face adjacent both of the panel opposite sides and second connectors on the wing wall rear faces adjacent the wing wall outer sides connect together to secure the overlapping walls and spandrel panels in substantially face to face contact.