Agilent Technologies J-BERT N4903, User Manual

Page: 185 / 434

Set the criteria for moving to the next sample point:
•
Number of Compared Bits
After this number of compared bits, the measurement stops for the
current sample point and moves to the next one.
•
Number of Errors
After this number of errors, the measurement stops for the current
sample point and moves to the next one. Thisallows you to speed up
the measurement. You can switch off this option if only the number
of compared bits is important.
N O T E
The measurement moves to the next sample point when the first of the two criteria
is reached.
Both numbers are ignored if the Fast Total Jitter measurement is selected.
Set the criteria for the sample delay:
• Resolution
Specifies the time distance between sampling points. A smaller value
yields more sampling points in a unit interval. You can enter the
resolution in UI or ps, ns, s, .... The timebase of the display is set on
the
View tab.
If the resolution used for the measurement is not high enough, the
bathtub curve does not clearly show the edges. For example, you may
wish to change the
Resolution from 0.01 to 0.005 and run the
measurement again.
• Optimization
You can choose between Edge Resolution Optimization , Fast Total Jitter
at BER , or None.
– Edge Resolution Optimization
Turns the resolution optimization on or off. If this option is
enabled, the Serial BERT intelligently sets a resolution so that
there are more sampling points at the edges. This can greatly
improve the results without dramatically increasing the duration
of the test.
The following illustration shows a diagram with default
resolution and no edge resolution optimization:
Advanced Analysis
5
Agilent J-BERT N4903 High-Performance Serial BERT 185