Personal active noise cancellation method and device having invariant impulse response
US5987144A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Oct 3, 1997 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Oct 3, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K2210/3221
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A selected electrical signal is first applied to the input of a source (30) to determine at least the impulse response (H), over a predetermined time, between the source output and the input of sensors (20). The values of the active cancellation control signal are determined in real time according to a predetermined law established in accordance with the previously determined impulse response (H), whereby the energy of the output signal from the sensors is minimised. The acoustic structure (2) is arranged so that the space (534) containing the sensors (20) and the source (30) is invariant at least during the determination of the active cancellation control signal and in the presence of a person, whereby the impulse response (H) between the output of the source (30) and the input of the sensors (20) may remain invariant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.