Timing jitter measurement of 40 Gbit/s RZ Raman loop data using gated autoand cross-correlation

We presented an all-optical timing jitter measurement technique based on optical cross-correlation. It is applied to pseudorandom 40 Gbit/s RZ data stream propagating in a recirculating, dispersion managed soliton loop. The timing jitter at 8000 km was measured as (2.5±0.2) ps, comparable to the value obtained by the RF method. The resolution of the method is 52 fs. The lower bound of the timing jitter measurement is 670 fs, limited by the auto-correlation width and the temporal resolution of the correlation setup. This scheme holds great potential for real-time jitter monitoring of optical networks due to its all-optical approach and repetition rate insensitivity.