Reduction of pulse-to-pulse interaction of optical RZ pulses in dispersion-managed fiber

When closely temporally separated two optical pulses of identical wavelength are transmitted in optical fiber, the pulse separation could be changed due to nonlinear effect. We evaluate the pulse-to-pulse interaction in dense dispersion management by simulation and experiment. First, we evaluate the influence of third order dispersion on the pulse-to-pulse interaction by numerical simulation of transmission. The interaction can be effectively reduced when dispersion shifted fiber for dispersion slope tuning is placed at input of EDFA repeaters. Then we performed a recirculating loop transmission experiment of 3.5-ps optical RZ pulses with 12.5-ps initial separation in dispersion flattened dispersion-managed fiber. The interaction can be greatly reduced by employing dense dispersion managed fiber, which is favorable for ultra-high speed OTDM transmission systems.