Rohde & Schwarz 1145.1010.04/05/06, Operating Manual

Page: 148 / 813

Calibration Overview R&S
®
ZVA/ZVB/ZVT
1145.1084.12 3.38 E-1
Calibration
Type Standards Parameter
s
Error Terms General
Accuracy Application
TRL (2-port) Reflect (at
both ports),
Through,
Line All See TOM High, high
directivity Reflection and
transmission
measurements on DUTs
with 2 ports, especially
for planar circuits.
Limited bandwidth.
TNA (2-port) Through,
Attenuation,
Symmetric
network All See TOM High, lowest
requirements on
standards Reflection and
transmission
measurements on DUTs
with 2 ports, especially
for planar circuits.
Enhanced
TOM (2-port, 3-
port or 4-port) Open,
Match (at
both ports),
Through All Reflection tracking,
Source match,
Directivity,
Load match,
Transmission
tracking
High Reflection and
transmission
measurements on DUTs
with 2, 3, or 4 ports,
especially at high
frequencies.
Enhanced TSM
(2-port, 3-port
or 4-port) Short,
Match (at
both ports),
Through All Reflection tracking,
Source match,
Directivity,
Load match,
Transmission
tracking
High Reflection and
transmission
measurements on DUTs
with 2, 3, or 4 ports,
especially at high
frequencies.
1) Or any other 3 known one-port standards. To be used in a guided calibration, the known standards must be declared to be
open, short, and match irrespective of their properties.
2) Or any other known two-port standard. See remark above.
The calibration type must be selected in accordance with the test setup. Select the calibration
type for which you can obtain or design the most accurate standards and for which you can measure
the required parameters with best accuracy.
Normalization
A normalization is the simplest calibration type since it requires the measurement of only one standard
for each calibrated S-parameter:
•
One-port (reflection) S-parameters (S
11
, S
22,
...) are calibrated with an open or a short standard
providing the reflection tracking error term.
•
Two-port (transmission) S-parameters (S
12
, S
21,
...) are calibrated with a through standard
providing the transmission tracking error term.
Normalization means that the measured S-parameter at each sweep point is divided by the
corresponding S-parameter of the standard. A normalization eliminates the frequency-dependent
attenuation and phase shift in the measurement path (reflection or transmission tracking error). It does
not compensate for directivity or mismatch errors. This limits the accuracy of a normalization.
Full One-Port Calibration
A full one-port calibration requires a short, an open and a match standard to be connected to a single
test port. The three standard measurements are used to derive all three reflection error terms:
•
The short and open standards are used to derive the source match and the reflection
tracking error terms.
•
The match standard is used to derive the directivity error.
A full one-port calibration is more accurate than a normalization but is only applicable for reflection
measurements.