R&S ZNL Series - Page 329

VNA GUI reference
R&S
®
ZNL/ZNLE
329User Manual 1178.5966.02 ─ 20
Log Freq
In a "Log Freq" sweep, the stimulus frequency is swept on a logarithmic scale over the
continuous frequency range. The frequency range (sweep range) and the internal gen-
erator power can be specified in the "Stimulus" settings (see Chapter 10.2.1, "Stimulus
tab", on page 311). The sweep points are calculated from the "Span" and the specified
"Number of Points" (n > 1) with the condition that the step width is constant on the log-
arithmic scale.
"Log Freq" sweeps are suitable for the analysis of a DUT over a large frequency range,
e.g. over several octaves. In a Cartesian diagram, the measurement result is displayed
as a trace over a logarithmic frequency scale. The following example shows a "Log
Freq" sweep with the forward transmission parameter S
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as measured quantity, and a
"dB Mag" scaled y-axis.
Tip: In "Log Freq" representation, limit lines and ripple limit lines appear as exponential
curves; see Chapter 9.4.1.1, "Rules for limit line definition", on page 230.
Remote command:
[SENSe<Ch>:]SWEep:TYPE LOGarithmic
Segmented
In a "Segmented" (linear) frequency sweep, the sweep range can be composed of sev-
eral continuous frequency sub-ranges or single frequency points. The sub-ranges are
termed sweep segments and are defined in the Define Segments dialog.
Sweep segments can overlap. The segment list must contain at least 2 distinct fre-
quency points before a segmented frequency sweep can be started.
Instrument settings such as the internal generator power, the measurement (IF) band-
width, and the frequency band of the local oscillator can be set independently for the
individual segments.
Due to this flexibility, segmented frequency sweeps are suitable for any detailed analy-
sis of a DUT at specified frequencies. In a Cartesian diagram, the measurement result
is displayed as a trace over a linear frequency scale ranging from the lowest to the
highest frequency point of all segments. The following example shows a segmented
frequency sweep with 2 segments. The forward transmission parameter S
21
is mea-
sured, and a "dB Mag" scaled y-axis is used. In the frequency range between the
sweep segments, the trace is displayed as a straight line.
Sweep Softtool