OPERATIONAL MONITORING OF TRANSMISSION ROUTES FOR DIGITAL SIGNALS.

摘要

1. A method of monitoring the operation of transmission links for digital signals, with at least one monitoring intermediate regenerator which is arranged between two line terminals and wich includes a fault monitoring device for the transmitted digital signal and a telemetry signal regenerator wich is connected thereto and wich transfers the monitoring information to an end station, wherein the telemetry signals are co-transmitted in this signal path in a different frequency position to the digital signal, but are separately regenerated and amplified in the intermediate regenerators in a cyclic sequence and the transmission of each subsequent telemetry signal is triggered by the reception of the telemetry signal of the preceding intermediate regenerator and in the event of a breakdown in the telemetry signal transmission, when the intermediate regenerator has received no telemetry signal for a specific length of time it commences the transmission of a telemetry signal wich contains an additional item of information, characterised in that at least a part of the telemetry signal formed by a monitoring intermediate regenerator of the one transmission direction is transmitted to the monitoring intermediate regenerator of the other transmission direction, wich is arranged in the same intermediate station, and is transmitted via the telemetry signal path of the opposite direction to the analysing end station.