Noise canceling microphone system and method for designing the same
US7245726B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2004 |
| Grant date | Jul 17, 2007 |
| Priority date | — |
| Expiry date | Feb 1, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2410/05
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A microphone housing improves the broadband noise canceling performance of an active noise canceling microphone system while also ensuring improved speech transmission through the system. First and second microphone elements are selected each having a diameter “d” and a thickness “t”. The two microphone elements are aligned axially with the back surfaces in contact and secured in an axially aligned cylindrical cavity within a cylindrically shaped housing. The cylindrically shaped housing has an outside diameter “D,” an interior cavity of diameter of “d,” and a height “2t”. The housing is exposed to an environment comprising both speech and noise. The first microphone element is adapted to receive a signal having both voice and noise components, while the second microphone element is adapted to receive a signal that is predominantly noise. A controller processes signals from the first microphone element and the second microphone element. The values of D and d are selected so to obtain a ratio of D over d between 1 and about 2.4 or a near field power difference of the first microphone signal and the second microphone signal between 8 dB and 11 dB. In the event the near field power di…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.