Filter architecture for an adaptive noise canceler in a personal audio device
US9076431B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 2012 |
| Grant date | Jul 7, 2015 |
| Priority date | — |
| Expiry date | Apr 23, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K2210/503
- 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 generates an anti-noise signal from a reference microphone signal and injects the anti-noise signal into the speaker or other transducer output to cancel ambient audio sounds. A processing circuit implements one or more adaptive filters that control the generation of the anti-noise signal. At least one of the adaptive filters is partitioned into a first portion having a fixed frequency response and a second portion having a variable frequency response. The partitioned filter may be an adaptive filter that generates the anti-noise signal directly from the reference microphone signal. An error microphone may be provided to measure the ambient sounds and transducer output near the transducer, and a secondary path adaptive filter included to generate an error signal from the error microphone signal, which may be partitioned, alone or in combination.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.