Information capacity for multi-span nonlinear optical fiber communication systems

We study the information capacity for an multi-span optical fiber transmission system with losses, dispersion, nonlinearity and amplified spontaneous emission (ASE) noise. A perturbation technique is developed to examine the information capacity, and a semi-analytic expression of the conditional probability distribution function is determined initially. A novel semi-analytical form of the information capacity was obtained, which can be extended to the wavelength division multiplexing (WDM) optical fiber communication systems. Computer simulations are executed for various parameters of the transmission system. The studied results indicate that the capacity does not monotone increase with the input power and is affected by the nonlinear coefficient prominently.