Anritsu 37 D Series, Maintenance Manual

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VNA TRACEABILITY
According to the International Vocabulary of Basic and General Terms
in Metrology (VIM), BIPM, IEC, IFCC, ISO, IUPAC, IUPAP, OIML, 2nd
ed., 1993, definition 6.10, traceability is defined as the property of the
result of a measurement or the value of a standard that can be related
to stated references through an unbroken chain of comparisons all hav-
ing stated uncertainties.
The stated references are stated reference standards. Stated means ex-
plicitly set forth in supporting documentation. Reference standard is a
standard generally having the highest metrological quality available
at a given location or in a given organization from which measure-
ments are derived. The stated references are usually national or inter-
national standards.
The unbroken chain of comparisons are the complete, explicitly de-
scribed, and documented series of comparisons that successively link
the value and uncertainty of a result of a measurement with the val-
ues and uncertainties of each of the intermediate reference standards
to the highest reference standard of which traceability for the result of
measurement is claimed.
The stated uncertainties are the uncertainties of measurement that
fulfill the VIM definition as the parameter and is associated with the
result of a measurement that characterizes the dispersion of values
that could reasonably be attributed to the measurand. The stated un-
certainty is evaluated and expressed according to the general rules
given in the ISO Guide to the Expression of Uncertainty in Measure-
ment.
The Vector Network Analyzer (VNA) is one of the most modern and ac-
curate measurement tools for microwave and RF applications, but
VNA requires calibration to enhance its measurement accuracy. There
are many ways to define proper measurement traceability for the VNA
in lieu of its system complexity and calibration schemes. Scattering
Parameters (S-Parameters) are the most common measurands of the
vector network analyzer.
PERFORMANCE VERIFICATION VNA TRACEABILITY
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