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Coherent Optical Transmission - Introduction

Demonstration of coherent optical transmission using a standard single mode fiber (SSMF) and considering its chromatic dispersion.

$c_0=299792458~\mathrm{m/s}$ (speed of light)
$\lambda_0 = 1550~\mathrm{nm}$ (reference wavelength)

Parameters (with default values):
$D_\mathrm{C}=17~\mathrm{ps/km/nm}$ (chromatic dispersion coefficent, [1])
$l = 10~\mathrm{km}$ (fiber length)
$R_s = 10~\mathrm{GBd}$ (symbol rate)

transfer function [2]:
$H(f,l)=e^{j \frac{\pi D_\mathrm{C} \lambda_0^2 }{c_0}\cdot l \cdot f^2 }$

[1] ITU-T G.652, Characteristics of a single-mode optical fibre cable
[2] M.Said, J. Sitch and M. Elmasry, "An electrically pre-equalized 10-Gb/s doubinary transmission system" Journal of Lightwave Technology, vol. 23, no. 1, pp. 388-400, Jan. 2005