| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a control technology for safely performing output control of Raman excitation light even though a transmission distance between nodes becomes long in an optical transmission system using Raman amplification. <P>SOLUTION: In the optical transmission system, a pilot signal PIL for connection confirmation of an optical transmission line is transmitted to a node A on an upstream side by modulating backward Raman excitation light PUMP to be given to an optical transmission line 1 on an uplink side. When the node A receives the pilot signal PIL, a response signal RES' is transmitted to a node B by modulating a backward Raman excitation light PUMP' to be given to an optical transmission line 1' on a downlink side. Then, confirming the reception of the response signal RES' at the node B to thereby switch the backward Raman excitation light to the optical transmission line 1 from a low output state to a high output state. <P>COPYRIGHT: (C)2009,JPO&INPIT |
