| 摘要 |
It is known for information relating to the bit error rate and other parameters of the transmission system to be transmitted to an evaluating terminal station in digital transmission systems by subjecting the useful signal pulses to additional jitter and, for this purpose, by coupling a signal which causes the jitter into the phase locked loop of the signal regenerator concerned which is used for clock extraction. To enable clear distinction between the telemetry signal and the monitoring station, a control signal is also transmitted according to the invention, similarly by subjecting the useful signal pulses to jitter, following transmission of the telemetry information by the monitoring station. This control signal is transmitted at a jitter frequency which is unable to pass through the downstream intermediate regenerators, with the result that the control signal can be identified only in the immediately following intermediate regenerator and the transmission of the telemetry signal is initiated therein. The invention is intended in particular for use in regenerative optical waveguide systems. <IMAGE> |
