Microphone actuation control system
US5297210A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 10, 1992 |
| Grant date | Mar 22, 1994 |
| Priority date | — |
| Expiry date | Apr 10, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R3/005
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved automatic microphone actuation control system. The system exhibits a high degree of resistance to inappropriate secondary microphone actuation by reverberant sound, even when two or more microphones in a system are operated at significantly different electroacoustic gains. The system further exhibits improved actuation sensitivity to local conference room speech occurring simultaneously with teleconference loudspeaker sound which is strongly coupled acoustically to the microphones. A Reverb Inhibit Bus, which is the maximum of a reduced level speaker inhibit signal and substantially attenuated versions of the DC microphone signal level representations, drives the microphone channels' noise adapting threshold circuitry. Such circuitry is driven in a manner to inhibit microphone actuation for teleconference loudspeaker sound reverberation and reverberation of local conference room speech which has already actuated a microphone. Further, a stronger level speaker inhibit signal is applied to each microphone channel through a direct inhibit bus. This inhibits microphone actuation by directly coupled loudspeaker sound, while not modifying the noise adapting threshold.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.