Analysis of subscriber stations in optical TDM/TDMA systems

摘要

The method involves sending a command from a central station of an optical TDM/TDMA system to a number of subscriber stations, that are at different distances which causes the burst signals transmitted from the subscribers to the central station to be received at different phases. A selected subscriber sends back a signal of a predetermined length having at least one 1-0 and one 0-1 transition. The time of reception of the returned signal is measured and the difference to a reference time is calculated and stored, to determine the signal run time of the station. A delay time for replay signals is adjusted by pref. using a delay line implemented for test purposes, in the subscriber stations by command of the central station, to give a coarse adjustment. The run time is finely matched to the central clock using a phase shift line in the central station. The adjustment process is repeated for each subscriber in regular periodic intervals to achieve an even response of the system.