R&S ZVB - Page 492

R&S
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ZVA / R&S
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ZVB / R&S
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ZVT GUI Reference
Channel Menu
Operating Manual 1145.1084.12 – 30 477
The characteristic data of the standards are very stable and independent of the individual calibration kit. It
is not required to deliver individual data with each kit and load the data into the analyzer. Instead the data
are already stored in the network analyzer (software option R&S ZVA-K8 and at least firmware version
2.45 are required). It is possible to export the stored data to a file. Use the "Cal-Kits" dialog of the network
analyzer for this purpose: "Channel" > "Calibration" > "Cal-Kits" > "Export Kit ..."
Sliding Match Standard
The sliding match standard is only contained in the calibration kit 1307.7300.31. It is a one-port standard
consisting of a precision waveguide section with a movable, low-reflection load element (sliding load). This
standard is used because no perfect match is available. However, a series of measurements at a given
frequency with equal mismatch and varying phase yields reflection factors that are located on a circle in
the Smith chart. The center of this circle corresponds to perfect match. The network analyzer determines
and further corrects this match point following I. Kása's circle-fitting algorithm.
To obtain the reflection coefficient for a perfectly matched calibration standard, the sliding load must be
measured at least at three positions which should be unequally spaced to avoid overlapping data points.
Increasing the number of positions to 4 – 6 can improve the accuracy. It is recommended to use the
positions listed below. They are optimized for the frequency range between 220 GHz and 325 GHz. Set
the adjustable screw of the standard to the following positions:
0 mm, 0.12 mm, 0.27 mm, 0.48 mm, 0.71 mm, 1.2 mm
If you accidentally unscrew the knob completely, simply screw it on again.
Enhanced Wave Correction
Activates or deactivates the system error correction of all a- and b-waves which are related to the ports of
the active channel calibration. The enhanced wave correction provides system error corrected complex
wave quantities and ratios for a set of analyzer ports.
If no channel calibration is available the enhanced wave correction is still applied, based on the factory
calibration. The calibration state labels in the trace lines of the wave quantities and ratios allow you to
distinguish the enhanced wave correction states:
 Enhanced wave correction off: no Cal label, Pcal label according to the power calibration state.
 Enhanced wave correction on, factory calibration: no Cal label, no Pcal label, irrespective of the
power calibration state.
 Enhanced wave correction on, channel calibration: Cal label, Pcal label according to the power
calibration state. A single power calibration at one port ensures power calibrated waves (Pcal) at
all ports.
For consistent measurements, it is recommended to use the enhanced wave correction in combination
with a (sufficient) set of system error corrections and power calibrations; see Enhanced Wave Correction
Procedure and Limitations.
In the present firmware version, the enhanced wave correction for all ports is referenced to the factory
calibration when a wave quantity or ratio for an uncalibrated port is selected. The Cal labels are removed
in all trace lines for ratios and wave quantities, including the traces lines for calibrated ports. The same
happens if an uncalibrated port is activated for the measurement using the Meas check box in the Port
Configuration dialog.
It is recommended to provide the calibrations for all ports before activating the enhanced wave correction,
creating traces, and activating ports.