Method and apparatus for dynamic sound optimization
US5434922A · kind A · utility
Inventors
Key dates
| Filing date | Apr 8, 1993 |
| Grant date | Jul 18, 1995 |
| Priority date | — |
| Expiry date | Apr 8, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G3/32
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
This invention comprises a system to compensate for the noise level inside a vehicle by measuring the music level and the noise level in the vehicle through the use of analog to digital conversion and adaptive digital filtering, including a sensing microphone in the vehicle cabin to measure both music and noise; preamplification and analog to digital (A/D) conversion of the microphone signal; A/D conversion of a stereo music signal; a pair of filters that use an adaptive algorithm such as the known Least Mean Squares ("LMS") method to extract the noise from the total cabin sound; an estimation of the masking effect of the noise on the music; an adaptive correction of the music loudness and, optionally, equalization to overcome the masking effect; digital to analog (D/A) conversion of the corrected music signal; and transmission of the corrected music signal to the audio system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.