Robust adaptive noise canceling (ANC) in a personal audio device
US9324311B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 2014 |
| Grant date | Apr 26, 2016 |
| Priority date | — |
| Expiry date | Mar 21, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K2210/3054
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
An adaptive noise canceling (ANC) circuit adaptively generates an anti-noise signal from that is injected into the speaker or other transducer output to cause cancellation of ambient audio sounds. At least one microphone provides an error signal indicative of the noise cancellation at the transducer, and the coefficients of the adaptive filter are adapted to minimize the error signal. In order to prevent improper adaptation or instabilities in one or both of the adaptive filters, spikes are detected in the error signal by comparing the error signal to a threshold ambient noise average. Therefore, if the magnitude of the coefficient error is greater than a threshold value for an update, the update is skipped. Alternatively the step size of the updates may be reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.