Advances in Radio Science
www.adv-radio-sci.net
1684-9965
1684-9973
5
Kleinheubacher Berichte 2006
2007
10.5194/ars-5-29-2007
http://www.adv-radio-sci.net/5/29/2007/
http://www.adv-radio-sci.net/5/29/2007/ars-5-29-2007.html
http://www.adv-radio-sci.net/5/29/2007/ars-5-29-2007.pdf
29
35
2007-06-12
Obstacle-based self-calibration techniques for the determination of the permittivity of liquids
I. Rolfes
rolfes@hft.uni-hannover.de
Institut für Hochfrequenztechnik und Funksysteme, Leibniz Universität Hannover, Appelstraße 9A, 30167 Hannover, Germany
In this contribution, different obstacle-based self-calibration
techniques for the measurement of the dielectric properties of
liquids are investigated at microwave frequencies. The liquid
under test is contained inside a waveguide, which is connected to
the ports of a vector network analyzer. The permittivity of the
liquid is characterized on the basis of the measured scattering
parameters.
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In order to extract the material parameters precisely and to
eliminate systematic errors of the setup, calibration measurements
have to be performed. For this purpose, different self-calibration
methods based on the displacement of an obstacle are considered.
The presented methods differ in that way, that either transmission
and reflection measurements or purely reflection measurements are
performed. All these methods have in common that the material
parameters are already calculable within a so-called
self-calibration procedure. Thus, a full two-port calibration of
the whole setup is not necessary. Furthermore, the methods can be
realized effectively in a practical setup having the advantage
that a rearrangement of the setup is not needed for the material
parameter measurements and that the liquid under investigation can
pass continuously through the measurement cell. This might be of
interest for the application in an industrial process, enabling
the continuous flow of the material while the parameter
characterization can take place at the same time.
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