| 摘要 |
<p>PCT No. PCT/GB92/01807 Sec. 371 Date May 24, 1994 Sec. 102(e) Date May 24, 1994 PCT Filed Oct. 1, 1992 PCT Pub. No. WO93/07687 PCT Pub. Date Apr. 15, 1993.A system for monitoring a network in which a station is connected to the network and includes a transmitter and a receiver. The transmitter outputs a signal modulated with outgoing traffic onto the network and the receiver receives a signal from the network modulated with incoming traffic. The station includes a monitoring circuit which introduces a variable delay in a signal from the transmitter and combines the delayed signal with the received signal so as to produce an output dependent upon the correlation of the signal from the transmitter and the received signal at the given delay. Preferably, the network is an optical network and the delay is introduced by a programmable delay line.</p> |
