| 摘要 |
PURPOSE:To increase the reliability of transmission system, by the reception without causing distortion of signals at reception section, through the switching by matching the phase of both signals without monentary interruption, in switching from a present transmission line to a spare transmission line. CONSTITUTION:Transmitting side devices 1-1, 1-2 are connected to reception side devices via normal current output switches 2-1, 2-2, current terminal stations 4-1, 4-2, current transmission lines 5-1, 5-2 and through current input switches 7-1, 7-2 and phase control circuits 9-1, 9-2, for transmission. If a failure takes place in the line 5-1, first a switching output switch 3 and a switching input switch 8-1 are closed to connect the current and spare transmission lines 5-1, 5-3 in parallel between the transmission and reception devices, and the phase of a signal at the spare side is corrected at the phase control circuit 9-1 to match it with the phase of the signal at the current side. Thereafter, the signal is switched in high speed from the current side to the spare side, and the current transmission line is disconnected by opening the current switches 2-1, 7-1 at the same time. |
