| 摘要 |
<p>PURPOSE:To use a monitor system for a submarine repeating system, etc., by transferring information on a monitor result as variation in mark rate of a pulse string transmitted to an opposite-direction repeating transmission line and by applying a phase-inversion fault search system even to a communication system which can not utilize an interposing couple. CONSTITUTION:Monitoring terminal station 1 and repeater 7 are connected together via repeating transmission lines 4 and 4', and a monitor signal pulse string containing a signal pulse of a repetitive frequency corresponding to a frequency assigned to each repeater 7 is transmitted to transmission line 4 and then transferred to repeater 7 at the next stage via driving circuit 33 of repeater 7. Further, a branch output from regenerator 11 of discrimination level control circuit 37' is applied to FF12 and information on the monitor result is obtained at the output of BPF14 and supplied to discrimination level control circuit 37. Then, circuit 37 varies the pulse discrimination level of regenerator 11' which performs the regenerative relaying of opposite-direction transmission line 4' so obtain a phase-inversion fault search system for a communication system which can not utilize an interposing couple. As transmission lines 4 and 4' mentioned above, optical fiber cables are used to obtain the effective monitor system for a submarine repeating transmission system.</p> |
