In-operation monitoring of communication transmission lines

摘要

In-operation monitoring system for communication transmission lines, in which the line terminating units and the intermediate stations are monitored at least in subregions. Of the line terminating units and the intermediate stations, at least a number contain in each case a telemetry signal regenerator for telemetry signals, which are transmitted in parallel with the wanted signals. To be able also when receiving irregular message sequences to determine the error location (X) in this case each of the messages is checked to ascertain whether the content of the message is corrupted. With an increasing number of cycles, the error location (X) is given by the location of steeply rising error signal frequency over the number of messages in the monitored transmission section.