Keysight Technologies N4960A User Manual page 22

Operation Overview
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The jitter amplitude (deviation in time from ideal location) of
deterministic jitter is bounded. Once enough transition edges have been
sampled to determine the peaks of the TIE envelope, additional
sampling will not show an increase in the peak instantaneous jitter. A
common graphical representation of jitter is referred to as a TIE
histogram, or simply a jitter histogram. The histogram shows peak
deviation versus number of samples.
histogram plot of sinusoidal jitter.
Figure 4. TIE histogram of pure sinusoidal jitter
The horizontal axis is jitter magnitude—deviation in time of the actual
edge location relative to its ideal location. The axis has polarity, with 0
deviation occurring in the center. Points to the right of center are from
transitions which occur after the ideal location (lag), while those to the
left of center occur before the ideal location (lead).
The vertical axis shows the number of occurrences, plotted on a log
scale. The characteristic shape reflects what is expected from a sine
wave. The amplitude is near the positive and negative peak for most of
the time, and in the zero crossing point for the least amount of time.
Generating a jitter histogram of pure deterministic jitter with a
measurement instrument which updates the plot as additional samples
are taken would quickly fill out the envelope, with no change in shape or
peaks as additional samples are taken.
Because deterministic jitter is bounded, its magnitude is usually
expressed as a peak to peak value. The units are either absolute time,
for example picoseconds (ps), or relative to bit time, in unit intervals
(UI).
Figure 4 shows a typical TIE
Keysight N4960A Serial BERT 17 and 32 Gb/s User Guide