Active acoustic attenuation and spectral shaping system
US5396561A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1992 |
| Grant date | Mar 7, 1995 |
| Priority date | — |
| Expiry date | Jul 27, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K2210/51
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
An active acoustic system provides attenuation and spectral shaping of an acoustic wave. A phase lock loop (304) phase locks to the input acoustic wave (6) and generates (306) a desired signal or tone (308) in given phase relation therewith. An error signal (44) from an error transducer or microphone (16) is summed (302) with the desired signal (308) and the resultant sum is supplied to the error input (202) of an adaptive filter model (40) which outputs a correction signal (46) to an output transducer or speaker (14) to introduce the canceling and shaping acoustic wave. In other embodiments, various combinations sum the desired signal (308) with the error signal (44), the model output correction signal (46), and the model input signal (42). Speaker and error path compensation (146, 318, 320) and feedback compensation (340) is provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.