Distortion cancellation for solitons carrying high speed information in WDM systems

The wavelength division multiplexing (WDM) type optical communication significantly increases the transmission capacity. However, one of the key issues is how we can reduce the pulse broadening and the interaction between the neighboring channels due to the nonlinear effects. The optical soliton offers the answer to this question. The soliton pulse can keep its shape during propagation, when there is a proper balance between the second order dispersion effect and the nonlinear Kerr effect, the main physical effects influencing the soliton propagation in fibers. Using the soliton approach, the pulse power has to be high enough to utilize the fiber non-linearity for keeping the pulse shape but its power has to be small enough to avoid the generation of higher order solitons. Simulations confirm our theoretical hypothesis for the design principles of soliton transmission in WDM systems. Due to new online filtering processes, soliton systems can now provide their benefits.