GUI Reference
R&S
®
ZNB/ZNBT
244
User Manual 1173.9163.02 ─ 38
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
on page 430). The sweep points are calculated from the "Span" and the speci-
fied "Number of Points" (n > 1) with the condition that the step width is constant on the
logarithmic 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 a stimulus range between 1 MHz and 6 GHz, the forward transmis-
sion 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 4.4.1.1, "Rules for Limit Line Definition"
Remote command:
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
ments may overlap. The segment list must contain at least 2 distinct frequency points
before a segmented frequency sweep can be started.
Instrument settings such as the internal generator power, the measurement (IF) band-
width, the selectivity of the measurement filter, the frequency band of the local oscilla-
tor, and the measurement time 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 in the stimulus ranges between 1 GHz and 2 GHz
and between 4 GHz and 6 GHz, respectively. The forward transmission parameter S
21
is measured, 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
