Concepts and Features
R&S
®
ZNA
199
User Manual 1178.6462.02 ─ 12
Internal Second Source
For a 4-port R&S
ZNA, a second internal source is available and hence the mixer mea-
surements outlined above (and many other measurements) can be performed without
an additional external generator. The limited source connectivity can be overcome with
option R&S
ZNA-B3 (see
Chapter 5.7.12, "Internal 3rd and 4th Source for 4-port
5.7.3.1
Calibration Options
In arbitrary mode, the R&S
ZNA automatically calibrates the source and receive fre-
quency ranges of all ports, according to the frequency conversion settings in the "Port
Settings" dialog or in dedicated configuration dialogs.
●
SMARTerCal is the recommended calibration method for frequency conversion
measurements.
●
For measurements on non-linear DUTs, an additional scalar power calibration is
recommended; for details refer to
●
A load match correction (optional) involves an additional reverse sweep. It can pro-
vide a significant improvement of the transmission S-parameter measurements if
the load ports are poorly matched.
Select the appropriate correction type according to your accuracy and speed require-
ments. Notice that none of the correction types provide the phase information for trans-
mission S-parameters.
5.7.3.2
Intermodulation Measurements
The intermodulation measurement is automatically enabled with option R&S
ZNA-K4.
The "Intermodulation" tab of the [Meas] softtool gives access to the measurement con-
figuration and selection of results (see
Chapter 6.2.6, "Intermodulation Tab"
An intermodulation measurement is performed with two RF signals of equal power but
different frequencies termed the upper and lower tone. The purpose of the measure-
ment is to test the properties of a DUT that is supplied with a signal that covers a fre-
quency band, typically a modulated RF channel. To simulate this scenario, the fre-
quency difference ("tone distance") between the upper and lower signal is chosen to be
small compared to the frequencies of the two tones:
f
L
≈
f
U
or
Δ
f = f
U
- f
L
≪
f
L
A nonlinear behavior of the DUT causes emissions at frequencies which correspond to
sums and differences of the upper and lower tone frequencies and their integer multi-
ples. These intermodulation products can be near the upper and lower tone frequen-
cies, as long as their order is odd.
The analyzer measures the intermodulation products of k
th
order IMk (where k = 3, 5,
7, 9) at the lower tone frequency minus (k – 1)/2 times the tone distance and at the
upper tone frequency plus (k – 1)/2 times the tone distance; see also
Optional Extensions and Accessories
