Noise-reducing directional microphone array
US9301049B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 2012 |
| Grant date | Mar 29, 2016 |
| Priority date | — |
| Expiry date | May 28, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2430/23
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In one embodiment, a directional microphone array having (at least) two microphones generates forward and backward cardioid signals from two (e.g., omnidirectional) microphone signals. An adaptation factor is applied to the backward cardioid signal, and the resulting adjusted backward cardioid signal is subtracted from the forward cardioid signal to generate a (first-order) output audio signal corresponding to a beampattern having no nulls for negative values of the adaptation factor. After low-pass filtering, spatial noise suppression can be applied to the output audio signal. Microphone arrays having one (or more) additional microphones can be designed to generate second-(or higher-) order output audio signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.