Technique of extracting 10 GHz clock pulses from 20 Gb/s OTDM signal by using an injected mode-locked fiber ring laser

The technique of optical time division multiplexing (OTDM) used in communications is very mature now, and will be put into commercial use in near future. At this turning point some technical problems are being paid much attention. Extraction of the clock with the same frequency as the original signal pulses from the multiplexing pulses is one of the key problems. Here we propose a novel all-optical scheme for extracting basic clock pulses from the OTDM optical pulse train and have successfully extracted the 10 GHz optical clock pulses from a 2/spl times/10 Gb/s OTDM signal.