Concepts and Features
R&S
®
ZNA
211
User Manual 1178.6462.02 ─ 12
Compared to conventional measurement methods, the mixer delay measurement
offers several additional advantages:
●
A network analyzer with standard functionality is sufficient.
●
Easy calibration using a calibration mixer.
●
"Two-Tone Generation and Combination"
●
Option R&S
ZNA-K9 requires
Direct Generator/Receiver Access
quency Conversion Measurements
option R&S
ZNA-K4.
A 4-port R&S
ZNA is recommended because of its second internal source. A dedicated
cable set for this measurement is provided with accessory R&S
ZNAxx-Z9.
Group Delay Calculation w/o LO Access
The group delay τ
g
of a circuit is defined as the negative derivative of its phase
response. Hence, for two tones with phases Φ1 and Φ2 and a frequency difference
("aperture") Δf:
ΔΦ
in
and ΔΦ
out
are the phase differences of the two tones at the input and output of the
DUT, respectively.
The phase difference of the source signal ΔΦ
in
and the aperture Δf are known quanti-
ties. ΔΦ
out
depends on the DUT and can be measured. As a phase difference, ΔΦ
out
is
stable against variations of the LO frequency, because those will affect both signals in
the same way. This means that the mixer delay measurement does not require any
synchronization between the analyzer and the LO signal, even if the LO shows a
noticeable frequency drift.
5.7.4
Phase Coherent Source Control
R&S
ZNA-K6
With option R&S
ZNA-K6, a four-port R&S
ZNA can generate signals with defined
phase. Typical application examples are measurements on balanced DUTs or the sup-
ply of antenna arrays which are designed for a well-defined radiation pattern.
If R&S
ZNA-K4 is installed in addition, phase coherent signals can be generated at
arbitrary amplitudes and frequencies.
Defined coherence mode requires an analyzer with at least two independent internal
sources. It is compatible with arbitrary single-ended or balanced port configurations. It
can also be used for frequency conversion measurements.
Optional Extensions and Accessories