| 摘要 |
<p>PURPOSE:To locate a distance of a fault point of an optical fiber transmission line including a relay point from a transmission signal stored in both terminal stations if a fault takes place in the transmission line by sending a reference bit at each reciprocating propagation time, receiving and storing the transmission signal sectioned by the reference bit. CONSTITUTION:The reference bit is sent from a transmitter 5 of a transmission section 1 of a terminal station at each rectiprocating time of an optical fiber transmission line 3 at first and the receiver 6 of a reception section 2 receives the transmission signal sectioned by the reference bit. If a fault takes place in the transmission line, the distance D from the terminal station B till the fault point is calculated by an equation of D(sec)=(tb-ta)/2, where ta and tb are time differences at terminal stations A, B between the data interruption time and the reference bit respectively. Thus, the distance to the fault point is calculated by dividing the said time by the propagating time of the optical fiber.</p> |
