Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pulse collision picture of inter-channel nonlinear interference noise in
  fiber-optic communications   We model the build-up of inter-channel nonlinear interference noise (NLIN) in
wavelength division multiplexed systems by considering the pulse collision
dynamics in the time domain. The fundamental interactions can be classified as
two-pulse, three-pulse, or four-pulse collisions and they can be either
complete, or incomplete. Each type of collision is shown to have its unique
signature and the overall nature of NLIN is determined by the relative
importance of the various classes of pulse collisions in a given WDM system.
The pulse-collision picture provides qualitative and quantitative insight into
the character of NLIN, offering a simple and intuitive explanation to all of
the reported and previously unexplained phenomena. In particular, we show that
the most important contributions to NLIN follow from two-pulse and four-pulse
collisions. While the contribution of two-pulse collisions is in the form of
phase-noise and polarization-state-rotation with strong dependence on
modulation format, four-pulse collisions generate complex circular noise whose
variance is independent of modulation format. In addition, two-pulse collisions
are strongest when the collision is complete, whereas four-pulse collisions are
strongest when the collision is incomplete. We show that two-pulse collisions
dominate the formation of NLIN in short links with lumped amplification, or in
links with distributed amplification extending over arbitrary length. In long
links using lumped amplification the relative significance of four-pulse
collisions increases, emphasizing the circularity of the NLIN while reducing
its dependence on modulation format.

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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
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The categories of this paper are: hep-ph
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The categories of this paper are: eess
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The categories of this paper are: q-bio
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The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
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The categories of this paper are: q-alg
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The categories of this paper are: q-fin
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The categories of this paper are: astro-ph