Concepts and features
R&S
®
ZNA
124
User Manual 1178.6462.02 ─ 20
The indices of the S-parameters described so far number the output and input ports of
a DUT; the parameters are referred to as single-ended S-parameters. The S-parameter
description can also be used to differentiate between different propagation modes of
the waves at the output and input ports. This results in the so-called mixed mode S-
parameters. The analyzer measures either single-ended or mixed mode S-parameters.
4.3.1.2
Redefined S-parameters
The analyzer firmware allows you to redefine the physical VNA ports, simply by speci-
fying:
●
a reference receiver ("a wave")
●
a measurement receiver ("b wave")
●
a generator ("Source" VNA or external generator port)
As a consequence, the measured S-parameters and other measured quantities are
also redefined.
●
The receivers and generators can be freely assigned, but without reusing the same
(original) physical port in different (redefined) ports. See
●
Redefined physical ports are global, persistent settings, i.e. they are valid for all
recall sets. A [Preset] does not reset the physical port configuration.
●
Redefining physical ports causes a factory reset.
Redefining physical ports can be used to insert external components (e.g. external sig-
nal separating devices, power amplifiers etc.) into the signal path. This allows you to
develop custom measurements, e.g. to test high-power devices and extend the
dynamic range.
Amp
Ext
Gen 1
VNA
2
1
Dual
Directional Coupler
DUT
Redefined Physical Port 1
a wave: b
1
b wave: b
2
Source: Ext Gen 1
Figure 4-4: Redefined physical port 1 (port 2 not used)
Measurement results