Chromatic Dispersion Monitoring for RZ-OOK Signals Using Half-Symbol Delay-Tap Sampling

A novel chromatic dispersion (CD) monitoring method of 40Gbps 33% duty-cycle return-to-zero on-off key (RZ-OOK), 50% duty-cycle RZ-OOK, and carrier-suppressed return-to-zero on-off key (CSRZ-OOK) signals by using half-symbol delay-tap sampling technique is demonstrated. The delay-tap sampling scatter plots not only identify three kinds of RZ-OOK signals but also reflect signal distortion caused by CD. The application of proposed scheme for CD monitoring in the range of 0-120 ps/nm is demonstrated and its tolerance to other impairments is also analyzed.