R&S ZNB Series User Manual page 186

®
R&S ZNB/ZNBT
4.5.5.4 Inline calibration
Any disturbance of the measurement setup after the calibration process inevitably pro-
duces errors. If a massive system error correction is required, e.g. if long RF cables
with high damping are used, those disturbances can lead to inaccurate and unreprodu-
cible measurement results. Especially in remote scenarios, such as measurements in a
thermal vacuum chamber (TVAC), a recalibration using traditional calibration kits or
calibration units is a costly and time consuming process.
The Rohde & Schwarz inline calibration system (ICS) R&S ZN-Z3x allows recalibrating
a running measurement setup without mechanically changing it. For each DUT port, an
inline calibration unit (ICU) is inserted between the corresponding VNA test port and
the DUT. The ICU remains within the signal path throughout the measurement (low-
loss through path) and, on request of the VNA, performs a full one-port calibration
(OSM) in-situ.
For n-port measurements with n>2, an initial n-port calibration of the test setup has to
be done.
Figure 4-11: ICU R&S ZN-Z32
Control connections are established via a central Inline Calibration Controller (ICC)
with:
●
2 CAN bus interfaces for connecting the ICUs
●
USB and LAN interface for remote control (from the R&S ZNB/ZNBT or a standard
Windows PC)
User Manual 1173.9163.02 ─ 62
Concepts and features
Calibration
186