Pulsewidth-tunable CS-RZ signal format with better tolerance to dispersion and nonlinear degradation in optical transmission system

A novel carrier-suppressed return-to-zero (CS-RZ) modulation format with tunable pulsewidth was proposed. A 10-Gb/s dispersion management transmission over a 320-km standard single-mode fiber was carried out to evaluate the performance of the novel modulation format. It was confirmed by experiment that the novel CS-RZ with short pulse is more tolerant to dispersion and nonlinearity than conventional CS-RZ format. Furthermore, the best transmission performance can be achieved by the novel CS-RZ format with 45% duty cycle, which has the narrowest optical spectrum width.