Ambient detector for dual mode anc
AssigneeGoogle Inc.
InventorsSteve RUI, Govind KANNAN
Life of this patent
Estimating the term…
Abstract
Active noise cancellation systems and methods include a feedforward path configured to receive a reference signal comprising ambient noise and adaptively generate an anti-noise signal to cancel the ambient noise. The adaptive filter is tuned in accordance with at least one parameter, which is set by a logic device configured to determine an ambient noise condition based the reference signal by estimating a fullband power of the reference signal, estimating a low-frequency power of the reference signal, comparing the fullband power and low-frequency power to one or more thresholds, and/or setting one or more ambient noise flags. The ambient noise condition may include a quiet background, a wideband noise condition, and/or a low-frequency dominant noise condition.
Claims16
An active noise cancellation system comprising:
- a feedforward path comprising an adaptive filter configured to receive a reference signal comprising ambient noise and adaptively generate an anti-noise signal to cancel the ambient noise at an eardrum reference point, wherein the adaptive filter is tuned in accordance with at least one parameter;
- and
- a logic device configured to determine an ambient noise condition based at least in part on the reference signal and adjust the at least one parameter to tune the adaptive filter, wherein determine the ambient noise condition comprises determining a current ambient sound mode based at least in part on a fullband power of the reference signal, a low-frequency power of the reference signal, and a difference between the fullband power of the reference signal and the low-frequency power of the reference signal.
3-5. (canceled)
A method comprising:
- receiving a reference signal comprising ambient noise;
- adaptively generating an anti-noise signal using an adaptive filter to cancel the ambient noise at an eardrum reference point;
- determining an ambient noise condition based at least in part on the reference signal, wherein determining the ambient noise condition comprises determining a current ambient sound mode based at least in part on a fullband power of the reference signal, a low-frequency power of the reference signal, and a difference between the fullband power of the reference signal and the low-frequency power of the reference signal;
- and
- tuning the ambient noise condition based at least in part on the ambient noise condition.
14-16. (canceled)
Dependencies are inferred from the claim text.