Agilent Technologies J-BERT N4903, Руководство пользователя

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About Jitter Tolerance Standards
Every Jitter Tolerance Compliance test requires a standard. You can use
one of the predefined standards. Additionally, you can define and use
your own "user-defined" standard.
In terms of the Serial BERT, a standard is represented by a sequence of
paired numbers. Each pair consists of a frequency value (Hz) and the
associated jitter amplitude value (UI).
Also part of a standard specification are the standard’s name and
descriptive text.
Predefined Standards
The Jitter Tolerance Compliance option provides a number of
predefined standards.
Predefined standards specify:
•
Jitter frequency range
The jitter frequency range may depend on the bandwidth of the
receiver being tested.
•
Bit rate range
Some standards define the jitter tolerance curve as a function of the
bit rate. If this is the case, the edges of the jitter tolerance curve are
shifted towards higher frequencies if the bit rate is increased, and
vice versa.
•
Jitter amplitudes in defined sections of the jitter frequency range
The slopes between adjacent sections may be double logarithmic
(shown as straight lines in the double logarithmic display) or are
calculated according to certain algorithms.
•
Data pattern to be used
This can be, for example, a certain PRBS-polynomial or a specific
test pattern.
•
Signal voltage range
Most standards refer to specific devices.
•
Jitter composition
A standard may prescribe that additional jitter components with
specific amplitudes have to be added.
The standards provided by Agilent can be chosen from a list of
predefined standards.
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Jitter Tolerance Tests
356 Agilent J-BERT N4903 High-Performance Serial BERT
Standard Specifications
Using Standards