User manual

Measurements
R&S
®
RTO
138User Manual 1316.0827.02 ─ 06
Meas. type Description/Result
17 Eye rise time Duration for signal to rise from lower reference level to upper reference level
See also: chapter 5.2.3.1, "Reference Level Settings", on page 153
18 Eye fall time Duration for signal to fall from upper reference level to lower reference level
See also: chapter 5.2.3.1, "Reference Level Settings", on page 153
19 Eye bit rate Frequency between two crossings
20 Eye amplitude V
top
-V
base
28 Jitter (peak to peak) Average of the jitter for both crossing points.
29 Jitter (6*σ) Jitter *6
30 Jitter (RMS) Average deviation of the time from the virtual crossing point.
The sequential numbers in the above table refer to the suffix required for remote control
commands for eye jitter measurements (see MEASurement<m>:EYEJitter:
LCHeck<n>:LOWer:LIMit on page 551 and following).
5.2.1.4 Histograms
Histograms are used to plot density of data, i.e. to display graphically how often which
signal values occur. In the R&S RTO, the histogram can be based on the input signal
levels (amplitudes) or the time base in a time domain measurement, or on frequencies
or frequency levels in a spectrum measurement.
Depending on which data the histogram is based on, a vertical or horizontal histogram
can be selected. A vertical, or amplitude, histogram displays horizontal bars across
amplitude values. A horizontal or time/frequency histogram displays vertical bars over
time/frequencies.
You can define up to 8 histograms in a diagram, one of them is displayed. They can be
created quickly with toolbar icons, or in the "Meas" menu >"Histogram" dialog box. To
switch the histogram display, tap the required histogram area, or select it in the "Histo-
gram" dialog box. For histogram measurements, the measured histogram is selected
independently in the measurement setup.
The following characteristic values can be determined for histograms (illustrated for a
vertical histogram):
Automatic Measurements