A novel analytical method for the BER evaluation in optical systems affected by parametric gain

A novel analytical method to evaluate the bit-error rate in optical links where the amplified spontaneous emission (ASE) noise at the receiver is a nonwhite random process is presented. The technique is used to estimate the impact of the nonlinear phenomenon called parametric gain on the performance of a wavelength-division-multiplexed (WDM) system. It is also compared with the Q-factor approximation, showing how this method may lead to significant errors.