OPTICAL FIBRE SIGNAL TRANSMISSION CONTROLLED BY RESPONSE SIGNAL FED BACK OVER SAME FIBRE FROM REMOTE MONITOR

摘要

Operators of fibre-optical transmission networks would like to monitor the signal quality at certain points in the network (for example at the network termination points). The invention specifies a system for this in which … …  - the useful signal (S1) is monitored indirectly, i.e. by monitoring an auxiliary signal (S2); …  - the means (4, 5, 6, 7) necessary for this can be simultaneously used for setting up a service channel between network node (1) and monitoring point (4); …  - the means necessary for this can be supplemented with little expenditure so that the signal monitoring can be coupled with an (advantageous) signal amplification. … …IMAGE…