Nonlinear transmission of noise along singlemode fiber at zero-dispersion wavelength

We analyse the influence of fiber nonlinearity on the transmitted relative intensity noise (RIN) and frequency noise (FN) spectra assuming second order dispersion different from zero. We show that fiber nonlinearity effects on RIN are irrelevant, contrarily to FN spectrum, where a tremendous enhancement at high frequencies can occur. To analyse the influence of nonlinear transmission at zero-dispersion wavelength on broad-band and long-haul systems, we consider an uniform amplified cascaded optical fiber link, where all system parameters such as fiber dispersion, loss, nonlinearity coefficient, and amplifier spacing, are the same all over the system