System and process for time delay estimation in the presence of correlated noise and reverberation
US7113605B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 14, 2005 |
| Grant date | Sep 26, 2006 |
| Priority date | — |
| Expiry date | Jul 14, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2430/23
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system and process for estimating the time delay of arrival (TDOA) between a pair of audio sensors of a microphone array is presented. Generally, a generalized cross-correlation (GCC) technique is employed. However, this technique is improved to include provisions for both reducing the influence (including interference) from correlated ambient noise and reverberation noise in the sensor signals prior to computing the TDOA estimate. Two unique correlated ambient noise reduction procedures are also proposed. One involves the application of Wiener filtering, and the other a combination of Wiener filtering with a Gnn subtraction technique. In addition, two unique reverberation noise reduction procedures are proposed. Both involve applying a weighting factor to the signals prior to computing the TDOA which combines the effects of a traditional maximum likelihood (TML) weighting function and a phase transformation (PHAT) weighting function.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.