Noise variance due to stimulated Raman scattering among channels of a wavelength-division-multiplexed system

We calculate the noise variance created by stimulated Raman scattering between signal channels of a wavelength-division-multiplexed system, accounting for group velocity dispersion. The results show that the noise variance is significantly reduced in the presence of dispersion. When average dispersion is zero, we see the noise variance scale quadratically with distance, while nonzero average dispersion yields linear growth with distance.