Gino Biondini
(Department of Mathematics, Ohio State University)
Nonlinear and Stochastic Effects in Optical Fiber Communications
Abstract
Optical fiber communications have experienced a period of tremendous growth;
in the last decade alone, system capacities have increased by four orders
of magnitude. The complexity of these systems has also increased,
however, making their mathematical modeling much more complicated.
Also, because transmission errors are handled by electronic components
at lower speeds, these systems are required to have extremely small bit
error ratios, which makes the prediction of actual error rates a difficult
mathematical and computational challenge. In this talk I will describe
recent work aimed at overcoming these challenges. In particular,
I will discuss two kinds of phenomena: dispersion management and the impact
of stochastic effects such as amplifier noise.
Dispersion management is a recently adopted technique which is known
to significantly improve system performance. At the same time, however,
I will show how it dramatically alters the underlying properties of the
system and results in a remarkedly different set of dynamical equations.
Amplifier noise is another important physical effect: large noise-induced
pulse distortions are rare, but those events are precisely one of the most
likely causes of transmission errors. In this case I will show howthe
careful application of importance sampling allows one to improve the efficiency
of Monte-Carlo simulations by several orders of magnitude, thus making
it straightforward to study events that would be almost impossible to observe
with a brute force approach.
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