Novel scheme of packet-level self-synchronization for all-optical packet networks

Abstract

A novel self-synchronization scheme is proposed that utilizes both cross gain modulation (XGM) and phase modulation, including self-phase modulation (SPM) and cross-phase modulation (XPM), in a semiconductor optical amplifier (SOA). The scheme consists of an SOA and a delay line interferometer. It is simple, integrable, and does not require any special marker pulses. With a proper design of the SOA parameters and interferometer delay time, a synchronization clock with an intensity contrast ratio of more than 20 dB can be obtained from return-to-zero (RZ) pseudorandom bit sequences (PRBSs) at different operation speeds.