Chromatic Dispersion Test
Two Types of Optical Dispersion
Chromatic Dispersion (CD) and Polarization Mode Dispersion (PMD) are both important linear distortions that affect the performance of optical systems.
The CD Challenge
Chromatic dispersion is a variation in the velocity of light (group velocity) with wavelength. This variation in velocity causes the pulses of a modulated laser source to broaden when traveling through the fiber; up to a point where pulses overlap and bit error rate increases. As this increase in bit error rate interferes with both the quality and speed of the signal, chromatic dispersion (CD) is a major limiting factor in high-speed transmission. Therefore, to ensure adequate quality of service, it is extremely important that carriers compensate for this type of signal distortion. The widespread use of DWDM systems covering the C and L bands (1530 nm to 1625 nm) will certainly create a need for accurate wideband CD compensators. Ensuring proper CD compensation starts with proper characterization of the effect.
Consider these measurement approaches:
Dispersion Measurements in the Field
to 40 Gbit/s
Complete Optical Component Characterization
Polarization Analysis Software
Field Measurement of Chromatic Dispersion
EXFO offers handheld and field-portable platforms with modular solutions for CD and PMD analysis.
A single module can provide automated CD and PMD measurement from a single connection at one end of a fiber run, with a one-push start button, at rates up to 10 Gbit/s.
For networks targeting 40 GBit/s transmission rates, EXFO offers CD measurements using the phase-shift method to provide uncertainty of less than 0.2%. EXFO Dispersion Measurement Products
Optical Vector Analysis
Luna Technologies' Optical Vector Analyzer™ (OVA) is the first instrument on the market capable of full and complete all-parameter linear characterization of single-mode optical components. The OVA provides comprehensive component characterization of Fiber Bragg Gratings, dispersion compensation modules, AWGs and many other optical devices. A complete vector measurement of the linear transfer function is used to characterize the device under test.
Luna Optical Vector Analyzer Information
Polarization Analysis Software
Luna
Technologies’ Polarization Analysis Software can be used to display
the response of an optical component to a simulated input
polarization state. This software, combined with the measurement
data from Luna’s Optical Vector Analyzer™, eliminates the tedious
and difficult task of polarization alignment often required for
measurement of today’s advanced optical components. The software
plots the insertion loss, group delay and impulse response of an
optical component to a user defined input polarization state.
Easy-to-use sliders allow the user to adjust the simulated input
polarization to any desired state. Also plotted are the minimum and
maximum insertion loss, and the group delay and chromatic dispersion
of the principle states of polarization (PSP). In a separate graph,
the software displays all of the polarization averaged quantities
(IL, GD, CD, etc.) as well as PMD, PDL, Jones matrix elements and
time domain information.Luna Polarization Analysis Software
Related Products
Luna Polarization Analysis Software EXFO Polarization and Dispersion Analyzers Luna Optical Vector AnalyzerRelated Manufacturers
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