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DJ & RJ
The Deterministic Jitter value is displayed in
picoseconds and the Random Jitter value is
displayed in fs.
Mask Margin
The
Switch to Mask Mode
button, located
between the Eye and Pattern buttons, is used
to find the maximum mask margin that
results in no more than a specified number or
ratio of failing points. The figure below shows
an example of where the user wants to
determine the maximum mask margin
available for the highest number of failing
points, but no more than 25.
The answer in this example is +13% for 8
points. Setting the margin below this level
would result in less failing points in total.
Setting the margin above this level would
result in fewer failing points.
The DSO has the following standard masks:
100Gbase-SR, LR, STM-1, STM-4, STM-16, Gb
Ethernet, Fiber Channel (1x), Fiber Channel
(2x, 4x), Fiber Channel (8x), Fiber Channel
(10x), 10 Gb Ethernet, and user defined
masks. New masks are continuously added.
Recent additions are QDR & FDR.
Horizontal
Bathtub
The Horizontal Bathtub curve is a depiction of
Bit Error Rate as a function of unit interval
(UI) position. As the measurement location is
swept across a UI, the BER is captured,
typically resulting in a figure that resembles a
cross section of a bathtub, thus the name
“bathtub curve”.
Vertical
Bathtub
The Vertical Bathtub curve is a depiction of
total vertical noise in signal under test.
Voltage points are plotted as a function of
BER.
