EXFO FTB-5600 Distributed PMD Analyzer - Manual (Page 87)

Managing Results
Distributed PMD Analyzer 81
Using Markers to Measure PMD Differences (Delta PMD Tab)
Using Markers to Measure PMD Differences
(Delta PMD Tab)
The Delta PMD tab is used to measure sections along the cumulative PMD
curve. The measurement is performed with two cursors; cursor A indicates
the beginning of the measurement and cursor B indicates the end. On
screen, you will see the positions of the markers, as well as the PMD
cumulative values. The application then computes and displays the square
rooted difference between cumulative PMD at the position of the two
markers.
The equation below illustrates how the difference is calculated.
ΔPMD
CumulPMDCursorB
2
CumulPMDCursorA
2
–
CumulPMDCursorB
2
CumulPMDCursorA
2
–
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