Network clock synchronisation

Abstract From the Canadian patent

In a network including an exchange having a masterclock and a number of subscriber stations connected to the exchange the exchange includes a delay line which receives incoming data. Samples are taken from different taps of the delay line and the tap carrying data in phase with the master clock identified and used to output data. By this arrangement the exchange can immediately lock onto the first pulse of a data cell header even though return data from the subscriber stations exhibits an arbitrary phase relationship with respect to the masterclock. This enables high speed operation of optical networks at data rates in the region of 150M/bits with circuitry which is cheaper and less complex …