Control device for activation of microphones to the systems of a teleconference

摘要

The invention relates to the selective control of the microphones in a system of a teleconference. / p & & p & in a teleconference system comprising a plurality of microphones 21, 23, 25 and a high - loudspeaker 29, the microphones are active independently in the addiction of three signals: 1, the speech signal picked up by the microphone was, 2, a signal of attack of the top - loudspeaker and 3, an electrical signal which is bound to the signals of the other microphones associated. A circuit a threshold adapts to the noise generated a voltage level representative of the background noise which is compared with the signal from a microphone, respectively for determining if this microphone which receives the speech. / p & & p & application to the installations of a teleconference.