| 摘要 |
PURPOSE:To make it possible to realize a light repeater of high reliability even when the reliability of each light source would be low, by changing light sources in sequence when a light source in operation runs into trouble. CONSTITUTION:For example, light source S1 is put into operation with only current switch 21 closed and light energy from light source S1 is transmitted to optical fiber transmission line f0 via light switch circuit 3. In case that light source S1 gets out of order, the post-stage repeater detects the fault happening to send out fault-position information characteristic of each repeater to a supervisory station via the optical fiber transmission line. In the supervisory station, the light repeater generating a fault-position information signal is sepcified and it is judged that the light source of the pre-stage light repeater is in trouble. The supervisory station transmits a light switching control signal up to the faulty repeater and puts switching control circuit 4 into opeation to open switch 21 while closing switch 22, and consequently while light source S2 is put into operation, light energy from only light source S2 is sent out to transmission line f0 via circuit 3. |
