Introducing the FTB-5800 Chromatic Dispersion Analyzer
Chromatic Dispersion Analyzer
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Basic Theory
Basic Theory
Chromatic dispersion is the natural broadening of light pulses as they travel
through optical fiber. The propagation characteristics of each wavelength
depend on the refractive index of the medium and on the non-linearity of
the propagation constant. These affect the travel time of each wavelength
through the fiber medium. An initially narrow pulse is widened as a result
of this, and as the pulses spread, they begin to overlap, causing the bit error
rate to increase.
High data rates mean pulses are closely spaced in time and have less room
to spread before they overlap. High channel count increases the difficulty
in correcting dispersion since each channel experiences different levels of
dispersion.
Long distances between regenerators require that dispersion be managed
very precisely because the effects accumulate over distance. As link length
and bit rate increase, the effects of chromatic dispersion also increase.
Chromatic dispersion is therefore one of the main factors limiting data
transfer for modern optical networks.
Typical Applications
Getting precise chromatic dispersion parameters helps you choose the
right dispersion-compensated fiber or material in order to reverse the
dispersion and dispersion slope before data are interpreted by the receiver.
