VNA concepts and features
R&S
®
ZNL/ZNLE
190
User Manual 1178.5966.02 ─ 19
The ranges of numerical values must be compatible with the instrument model. The
conditions for the stimulus range depend on the sweep type:
●
"Lin Freq" / "Log Freq" / "Segmented"
The supported frequency range depends on the instrument type; for an overview
refer to
–
For "Lin Freq" and "Log Freq" sweeps, if the number of sweep points is greater
than 1, the stop frequency must be greater than the start frequency and the
span must be
≥
1 Hz. If a stop frequency smaller or equal than the current start
frequency is set, then the start frequency is adjusted and vice versa.
–
For "Segmented" sweeps, the start and stop frequency in a sweep segment
must not be different. So with a segmented sweep you can measure n
1
points
at frequency f
1
(in segment 1), n
2
points at frequency f
2
(in segment 2) etc.
●
"Power" (R&S
ZNL only)
Start and stop power are both entered in absolute units (dBm). Start and stop
power must be different; the stop power must be larger than the start power. If a
stop power smaller than the start power is set, then the start power is adjusted
automatically and vice versa.
The power corresponds to the actual source power at the test ports (channel base
power P
b
). After a port power calibration, this source power is available at the cali-
brated reference plane.
●
"CW Mode"
The [Freq] and [Span] function keys define the fixed stimulus frequency ("CW Fre-
quency") and the "Number of Points" of the measurement. The other sweep
parameters (e.g. the "Sweep Time") are set via [Sweep] > "Sweep Params".
●
"Time"
The [Freq] and [Span] function keys define the fixed stimulus frequency ("CW Fre-
quency") and the total sweep time ("Stop Time") of the measurement. The other
sweep parameters (e.g. the "Number of Points") are set via [Sweep] > "Sweep Par-
ams".
The sweep time is entered in seconds and must be positive.
The selected sweep range applies to all source and receive ports of the analyzer.
9.1.5
Data flow
The analyzer processes the raw measurement data in a sequence of stages to obtain
the displayed trace. The following subsections give an overview.
9.1.5.1
Channel data flow
The diagram below illustrates the data processing stages for the entire channel. All
stages are configurable.
Basic concepts
