Evolution of stimulated Raman crosstalk in wavelength division multiplexed systems

An exact analytical solution for the evolution of stimulated Raman crosstalk in a singlemode WDM fiber system is presented utilizing the triangular approximation to the Raman gain spectrum. This approach provides a rigorous expression for crosstalk impairment. In the limit of small interchannel power exchange, our result reduces to Chraplyvy's previous estimate. Our formulation can be employed to predict the Raman penalty in future multiwavelength fiber communication systems.