System for computationally efficient active control of tonal sound or vibration
US7224807B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 2002 |
| Grant date | May 29, 2007 |
| Priority date | — |
| Expiry date | Sep 9, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K2210/321
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A noise or vibration control system reduces a sampling rate and reduces a control rate to improve computation efficiency. The present invention permits the use of a sample frequency (fs) that is less than twice the frequency of interest (fd). The sensed signals are filtered to extract a particular frequency range with a lower bound given by (2n−1)*fs/2 and an upper bound given by (2n+1)*fs/2, where n is an integer chosen so that the frequency of interest (fd) is within the extracted frequency range. The control commands are also calculated at a reduced rate, which is dependent upon the bandwidth of the tone, rather than the absolute frequency of the tone. Rather than updating the control signals directly on the sampled sensor data yk as it enters the computer, the control computations are done on the harmonic components ak and bk, or equivalently on the magnitude and phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.