EXFO FTB-5800 Chromatic Dispersion Analyzer for FTB-400 - Manual (Page 41)

Operating Your Chromatic Dispersion Analyzer
Chromatic Dispersion Analyzer 35
Measuring Chromatic Dispersion
Measuring Chromatic Dispersion
You can perform both single and multiple acquisitions on fibers.
To perform multiple acquisitions on the same fiber you must define the
number of measurements and the interval between them.
The average time between acquisitions must be of at least five minutes.
The five-minute period takes into account the time the application might
take to characterize the fiber link, depending on the quality of the signal. In
order for the value entered here to be valid, you must add five minutes to
the estimated acquisition time.
If you stop an acquisition before it is complete, the results acquired until
then will be displayed. However, in some cases, a minimum number of
points must be acquired for the application to calculate chromatic
dispersion and display a trace (e.g., at least three points for the
3-Term Sellmeier type and at least five for the 5-Term Sellmeier).
To perform single or multiple acquisitions on a fiber:
1. If necessary, create a file (see Creating a File on page 34).
2. Set the general acquisition parameters as explained in Setting Up Your
Chromatic Dispersion Analyzer on page 13.
3. On the Parameters tab, click the Multiple Acquisitions button to
access the parameters dialog box.
I
MPORTANT
Do not change the test fiber between two acquisitions of a
multiple-measurement test since parameters set for a specific fiber
may not apply to all fibers.