Glossary: Frequently Used Terms
R&S
®
ZVA
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Getting Started 1145.1090.62 ─ 13
Topology:
Assignment of the physical ports of the NWA to the logical ports used for
the measurement of mixed mode S-parameters (balance-unbalance conversion).
TOSM:
A calibration type using a Through plus the one-port standards Open, Short,
Match, to be connected to each calibrated port. Classical 12-term error model, also
referred to as SOLT. See also UOSM.
TRL:
A calibration type using the two-port standards Through and Line, which are both
assumed to be ideally matched. Beyond that, the through must be lossless, and its
length must be exactly known. Especially useful for DUTs in planar line technology.
TRM:
A calibration type which requires a low-reflection, low-loss Through standard
with an electrical length that may be different from zero, a Reflect, and a Match. Espe-
cially useful for DUTs in test fixtures.
TSM:
A calibration type using three fully known standards (Through, Short, Match),
recommended for 2-port measurements on coaxial systems.
U
UOSM:
A variant of TOSM calibration using an unknown but reciprocal Through stand-
ard. Especially for port combinations with different connector types.
