| 摘要 |
PURPOSE:To execute the conference telephone service with the same quality as the conventional service, by selecting 2 subscribers in order from the maximum voice level among all the subscribers, in the conference telephone system by which 3 or more subscribers are able to call at the same time. CONSTITUTION:When the conference is in a speech state, both the speaker's voice and other subscriber's background noise are input to the 2 subscriber sampling circuit 2, both the speaker's voice and the maximum background noise are selected and added, and the maximum background noise, the speaker's voice, and the voice and noise are sent out to the speaker, one subscriber to whom the noise has been selected, and other subscribers, respectively, by the distributing circuit 4. In case of the conversational state of 2 subscribers, the other speaker's voice is selected instead of the maximum background noise, its state becomes te regular telephone service between 2 subscribers, and othe subscribers are able to listen to the 2 subscriber's conversation. In the event of a cross state, the speaker himself hears other speaker's voice, and therefore, it can be known that 2 or more subscribers are speaking. |
