ADAPTIVE FEEDBACK CONTROL FOR EARBUDS, HEADPHONES, AND HANDSETS

摘要

A system and method are described in which additional signal processing is performed during in-the-field use of a personal listening device so that a control filter of a running acoustic noise cancellation process is selected based on the delta/difference between reference and residual error microphone signals of the device. This delta value represents the passive sound attenuation provided by the personal listening device. In other words, the control filter, which may be a programmable digital filter, is selected directly based on the delta between the level of external and error microphones. This delta value serves as an estimate of the current fit/leakage scenario, which enables the resulting anti-noise signal to better match a wide range of acoustic leaks (that may be caused by different earphone fits within the user's ear, or different ways a phone handset is held against the ear).

主权项

1. A method for in-the-field use of a personal listening audio device, comprising:
computing a difference between a reference microphone signal from a reference microphone and an error microphone signal from an error microphone associated with the personal listening audio device; generating a gain value for attenuating ambient noise based on the computed difference between the reference microphone signal and the error microphone signal; selecting a control filter for use during performance of acoustic noise cancellation (ANC) based on the generated gain value; and performing an ANC process during in-the-field use of the personal listening audio device using the selected control filter to produce an anti-noise signal by the device.