Continuous adaptation of secondary path adaptive response in noise-canceling personal audio devices
US9214150B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 27, 2012 |
| Grant date | Dec 15, 2015 |
| Priority date | — |
| Expiry date | Jan 24, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K2210/3049
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A personal audio device, such as a wireless telephone, includes an adaptive noise canceling (ANC) circuit that adaptively generates an anti-noise signal from a reference microphone signal and injects the anti-noise signal into the speaker or other transducer output to cause cancellation of ambient audio sounds. An error microphone is also provided proximate the speaker to provide an error signal indicative of the effectiveness of the noise cancellation. A secondary path estimating adaptive filter is used to estimate the electro-acoustical path from the noise canceling circuit through the transducer so that source audio can be removed from the error signal. Noise is injected either continuously and inaudibly below the source audio, or in response to detection that the source audio is low in amplitude, so that the adaptation of the secondary path estimating adaptive filter can be maintained, irrespective of the presence and amplitude of the source audio.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.