| 摘要 |
PURPOSE:To set one satellite link among channels and to eliminate a failure in conference telephone due to propagation delay by providing a conference service device which mixes a voice output of a down channel to each ground station for a satellite or accompanying exchange. CONSTITUTION:Three ground stations A, B, and C are connected together through the satellite, and when a conference service call is inputted from a ground network to the trunk circuit 70 of the station A and connected to subscribers of the station B and C, the controller 17 of the station A reports that a conference service call for the stations B and C is generated through a circuit 10, and informs the stations B and C of the generation of the conference service through a radio transmitter 12 and an antenna 14 over a satellite channel for control. The stations B and C each select one of free trunks, and the device 17 of each station connects a down satellite channel which corresponds fixedly to the trunk reported from other two stations to a conference service device 16 through a radio receiver 13 and a switch circuit 15 to connect its output to the trunk of its station. Consequently, one satellite link is set up among callers to obtain the same propagation delay with two-party call service. |
