Microphone circuits having adjustable directivity patterns for reducing loudspeaker feedback and methods of operating the same
US7068797B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 2003 |
| Grant date | Jun 27, 2006 |
| Priority date | — |
| Expiry date | Aug 28, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R25/407
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A microphone circuit includes a first microphone, a second microphone, an adjustable delay unit, and a combiner. The first microphone generates a first microphone signal that includes a contribution associated with an output signal that is generated by a loudspeaker in response to an input signal. The second microphone generates a second microphone signal that includes a contribution associated with the output signal from the loudspeaker. The adjustable delay unit delays the second microphone signal relative to the first microphone signal by a delay value. The combiner combines the delayed second microphone signal and the first microphone signal to provide a combined microphone signal. The adjustable delay unit adjusts the delay value so as to reduce at least a portion of the contribution to the combined microphone signal that is associated with the output signal from the loudspeaker.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.