Close-talk detector for personal listening device with adaptive active noise control

摘要

A close-talk detector detects a near-end user's speech signal, while an adaptive ANC process is running, and in response helps prevent the filter coefficients of an adaptive filter of the ANC process from being corrupted, thereby reducing the risk of the adaptive filters diverge. Upon detecting speech using a vibration sensor signal and one or more microphone signals, the detector asserts a signal that slows down, or even freezes or halts, the adaptation of the adaptive filter. The signal may be de-asserted when no more speech is being detected, thereby allowing the adaptive ANC process to resume its normal rate adaptation of the filter. The detector may continuously operate in this manner during the call, as the user talks and then pauses and then resumes talking. Other embodiments are also described.

主权项

1. A method for active noise control (ANC) in a personal listening device that is at a user's ear, comprising:
performing an adaptive active noise control (ANC) process in a personal listening audio device, wherein the personal listening audio device has an earphone housing or a mobile phone handset housing containing a speaker driver system and that is up against the user's ear, and wherein the ANC process uses an adaptive control filter to produce an anti-noise signal that is fed to the speaker driver system; computing a statistic using an L2 norm of a cross-correlation vector between a vibration sensor and an acoustic microphone that are integrated in the earphone housing or mobile phone handset housing of the device; comparing the statistic to a threshold; declaring a close talk event when the statistic is greater than the threshold; and slowing down or freezing adaptation of the adaptive control filter, in response to the close talk event being declared.