Concepts and features
R&S
®
ZNA
242
User Manual 1178.6462.02 ─ 20
IPk
in
= P
L, in
+ IMk
rel
/ (k – 1)
The intermodulation suppression generally decreases with increasing stimulus power.
The intercept point is equal to the lower tone power for which the intermodulation sup-
pression would reach 0 dB. Output and input intercept point differ by the attenuation of
the lower tone signal upon transmission through the DUT. The intercept point is a
mathematical concept. For most DUTs, it is beyond the nominal power operating
range.
Filter settings
Intermodulation measurements require frequency-selective filter settings. When an
intermodulation result is selected, the analyzer checks whether the IF bandwidth of the
active channel is 1/100 of the distance between the upper and the lower tone ("Tone
Distance") or less. If not, the analyzer displays a tooltip.
Selectivity is automatically set to high, but can be changed manually.
4.7.3.3
Harmonics measurements
Harmonics are signals at an integer multiple of the fundamental frequency. The funda-
mental is the first harmonic, the nth harmonic is n times the frequency of the funda-
mental. The production of harmonic frequencies by an electronic system, when a sig-
nal is applied at the input, is known as harmonic distortion.
Harmonic distortion measurements can be performed irrespective of the sweep type: A
frequency sweep yields the harmonics as a function of the frequency, a power sweep
yields the power-dependent harmonics at fixed frequency.
Harmonic power calibration
Due to the different frequency ranges of the input and output signals, the harmonic
power calibration must be performed in two steps. For a test setup where the DUT's
input signal (fundamental signal) is provided by analyzer port 1 and where the har-
monic is analyzed at port 2, the following test setups are required
1. Source power calibration of the fundamental signal and the harmonic frequency
ranges
A power sensor is connected to port 1. The source power is calibrated over the
selected sweep ranges. The correction data for all calibration sweeps is stored.
2. Receiver power calibration for the selected harmonics.
No external device is needed. The receiver (port 2) is calibrated at the harmonic
frequency using the source signal from port 1, calibrated in the first step.
4.7.3.4
Scalar mixer measurements
Scalar Mixer measurements are included in option R&S
ZNA-K4.
RF mixers convert an RF signal at one frequency into a signal at another frequency.
The frequency that is to be shifted is applied at the RF input. The frequency shifting
Optional extensions and accessories
