System Overview
R&S
®
ZVA
85
Quick Start Guide 1145.1090.62 ─ 10
3. 3. DUT with one balanced and one single-ended port.
4. 4. DUT with two balanced ports or one balanced and two single-ended ports. Both
device types are fully characterized by 4x4 mixed mode S-matrices.
3.4 Calibration
Calibration or "system error correction" is the process of eliminating systematic, repro-
ducible errors from the measurement results. The process involves the following stages:
1. A set of calibration standards is selected and measured over the required sweep
range. For many calibration types the magnitude and phase response of each cali-
bration standard (i.e. its S-parameters if no system errors occur) must be known
within the entire sweep range. In some calibration procedures (TRL, TNA, TRM), part
of the characteristics of the standards can be auto-determined due to implicit redun-
dancy (self-calibration).
2. The analyzer compares the measurement data of the standards with their known,
ideal response. The difference is used to calculate the system errors using a particular
error model (calibration type) and derive a set of system error correction data.
3. The system error correction data is used to correct the measurement results of a DUT
that is measured instead of the standards.
Calibration is always channel-specific because it depends on the hardware settings, in
particular on the sweep range. The means that a system error correction data set is stored
with the calibrated channel.
The analyzer provides a wide range of sophisticated calibration methods for all types of
measurements. Which calibration method is selected depends on the expected system
Calibration
