Dual-microphone spatial noise suppression
US8098844B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 5, 2006 |
| Grant date | Jan 17, 2012 |
| Priority date | — |
| Expiry date | Apr 10, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2410/07
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Spatial noise suppression for audio signals involves generating a ratio of powers of difference and sum signals of audio signals from two microphones and then performing noise suppression processing, e.g., on the sum signal where the suppression is limited based on the power ratio. In certain embodiments, at least one of the signal powers is filtered (e.g., the sum signal power is equalized) prior to generating the power ratio. In a subband implementation, sum and difference signal powers and corresponding the power ratio are generated for different audio signal subbands, and the noise suppression processing is performed independently for each different subband based on the corresponding subband power ratio, where the amount of suppression is derived independently for each subband from the corresponding subband power ratio. In an adaptive filtering implementation, at least one of the audio signals can be adaptively filtered to allow for array self-calibration and modal-angle variability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.