Study of crosstalk propagation in all-optical networks using perturbation theory

Abstract

In high-speed <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">all-optical</i> <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">networks</i> , nodes are able to switch signals in the optical domain, without any electronic conversion or signal regeneration. These networks are prone to optical leaks ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">crosstalk</i> ) within the switches. Because of the lack of regeneration, crosstalk can propagate over very long distances along with legitimate signals. In this work, we consider the interplay between fiber nonlinearity and crosstalk signals over long distance as the source of performance degradation, measured in terms of Q factor. We present an analytical crosstalk model for all-optical networks and give expressions for the performance degradation resulting from the joint propagation of a signal and crosstalk in large networks. This analytical technique uses a continuous wave assumption and is based on perturbation theory. Analytical calculations required by this model are much less computationally intensive than simulations. Simulations are carried out to validate our analytical model and good agreement is found between the analytical model and simulations.