Concepts and Features
R&S
®
ZNB/ZNBT
223
User Manual 1173.9163.02 ─ 53
The lower tone signal is generated at port 1, the upper tone is provided by the external
generator. Both signals are combined externally and fed to the DUT input. The intermo-
dulation quantities can be measured at the DUT output (transmitted wave b2). It is pos-
sible to interchange the ports no. 1 and 2.
For a R&S
ZNB/ZNBT with two internal sources, you can use any combination of ana-
lyzer ports that are supplied by different internal sources to generate the lower and
upper tones (see
Chapter 5.7.8, "Internal Second Source"
on page 227). In the follow-
ing example, port 3 of a R&S
ZNB replaces the external generator. For a R&S
ZNBT
with more than 8 ports the lower and upper tone could be provided by ports 1 and 9,
for example.
VNA
1
3
2
4
Upper Tone
DUT
1
2
Lower Tone
An external combiner is required anyway.
Operation with
not
used.
The intermodulation distortion measurement can be extended to frequency-converting
DUTs. E.g., it is possible to feed the two-tone source signal to the RF input of a mixer
and measure the intermodulation distortion of the IF output signal, after conversion
with an additional LO signal.
Optional Extensions and Accessories
