Dependence of optimum residual dispersion per span on the number of spans for various signaling formats over 43 Gbit/s SSMF transmission system

The dispersion map optimization of duobinary, carrier-suppressed return-to-zero (CS-RZ), and duobinary CS-RZ signaling formats for 43 Gbit/s systems with standard single- mode fiber is analyzed through extensive numerical simulation for various number of spans. It is shown that the optimum pre-compensation dispersion for those formats follow the same rule shown elsewhere for other formats. A simple relation between the optimum residual dispersion per span and the number of spans is for the first time demonstrated.