User guide

Eye Opening
Eye Opening - Concepts
The Eye Opening measurement generates a three-dimensional bit error rate (BER)
diagram as a function of the sample delay and the sample threshold. With this
measurement, the complete eye of the DUT output signal is measured. The results
comprise the voltage and timing of the eye opening and the optimum sampling
point.
To get the result, the sampling delay and the input threshold of the signal are shifted
within 1.5 signal periods and a user-defined voltage range. The results comprise
the voltage and timing of the eye opening and the optimum sampling point.
An example, that illustrates the general principle of the Eye Opening measurement
is shown in the figure below.
In detail, the measurement is not that simple and more precise as it derives the
contour of the eye from the bit error rates that have been measured.
Three Available Views
The Eye Diagram can be visualized in three different ways:
•
Contour Plot
Advanced Analysis 6
Agilent J-BERT N4903B High-Performance Serial BERT 287