MONITORING AND/OR CONTROLLING DEVICE AND PROCESS

摘要

In order to convey in a simple manner controlling and/or monitoring signals as subsidiary signals in a control or monitoring channel of an optical fibre information transmission system, the subsidiary signals are filtered out of the whole band in intermediate repeaters and/or amplifiers of a transmission section and are optically modulated with other subsidiary signals (line 456) by a modulator (458) or gathered into a multiplex signal in a device (45), while maintaining the optical carrier frequency. The result of this signal processing is returned to the transmission section at the output of the intermediate repeater or amplifier.