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ET User’s Guide 6-19
Calibrating for Increased Measurement Accuracy
Calibration Kits
NOTE
Calibration kit definitions must be in DOS format. LIF format is not
supported for cal kit definitions.
3. Verify performance.
Step 1: Determine
the Characteristics
of the Calibration
Standards Determine the characteristics of the calibration standards you plan to
use. In particular, these are the characteristic impedance (Z
0
), the delay,
and the loss. These characteristics are common for the four supported
standard types used by the analyzer. Additionally, the capacitive model
parameters, C
0
, C
1
, C
2
, and C
3
are necessary for fully defining the open.
These electrical characteristics can be mathematically derived from the
physical dimensions and material of each calibration standard or from
its actual measured response.
About Calibration Standards.
A calibration standard is a
specific, well-defined, physical device used to determine systematic
errors. Each standard has a precisely known or predictable magnitude
and phase response as a function of frequency. The response of each
standard is mathematically defined in the error models used by the
network analyzer.
A standard type is one of four basic types that define the form or
structure of the model to be used with that standard (i.e., short, open,
load, and through).
Standard characteristics are the numerical, physical characteristics of
the standards used in the model selected.
Typical calibration standards are throughs, opens, shorts, and loads. All
of these standards offer the advantage of broadband frequency coverage.
They are used singly or in combination, depending on the type of cal.
Open defines the standard type of an open circuit.
Short defines the standard type of a short circuit.
Load defines the standard type of a load.
Through defines the standard type as a transmission line of
specified length. The through has zero length when the
two test ports can be connected directly together.