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A time domain transmission measurement system for dielectric characterizations

Published online by Cambridge University Press:  19 April 2012

Bianca Will ,
Michael Gerding ,
Christian Schulz ,
Christoph Baer ,
Thomas Musch  and
Ilona Rolfes
Bianca Will*
Affiliation:
Institute of Microwave Systems, Ruhr-University Bochum, Universitätsstr. 150, 44801 Bochum, Germany. Phone: +49 234 32 26983.
Michael Gerding
Affiliation:
Institute for Electronic Circuits, Ruhr-University Bochum, Universitätsstr. 150, 44801 Bochum, Germany.
Christian Schulz
Affiliation:
Institute of Microwave Systems, Ruhr-University Bochum, Universitätsstr. 150, 44801 Bochum, Germany. Phone: +49 234 32 26983.
Christoph Baer
Affiliation:
Institute for Electronic Circuits, Ruhr-University Bochum, Universitätsstr. 150, 44801 Bochum, Germany.
Thomas Musch
Affiliation:
Institute for Electronic Circuits, Ruhr-University Bochum, Universitätsstr. 150, 44801 Bochum, Germany.
Ilona Rolfes
Affiliation:
Institute of Microwave Systems, Ruhr-University Bochum, Universitätsstr. 150, 44801 Bochum, Germany. Phone: +49 234 32 26983.
*
Corresponding author: B. Will Email: bianca.will@rub.de
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Abstract

Delay time measurements are a commonly used technique for the characterization of dielectric materials. Especially with regard to the characterization of water–solid mixtures like soil or grain delay time measurements, e.g., time domain reflectometry offers a powerful method. However, the accuracy of reflection measurements is limited due to multiple reflections caused by inhomogenities of the environmental material of the sensor. This contribution deals with an improved sensor design based on time domain transmission (TDT) measurements. Thus, the first received impulse includes the necessary information. Multiple reflections are received at later time steps and their influence on the measurement accuracy is nearly negligible. To improve the performance and the applicability of the designed sensor, a cost–efficient TDT system is designed, which is integrated in the sensor. Additionally, a so-called “concentric reversion coupler” is used, which offers the possibility to perform TDT measurements without the necessity of external measuring ports.

Keywords

Characterization of material parameterMicrowave measurement
Type
Research Papers
Information
International Journal of Microwave and Wireless Technologies , Volume 4 , Special Issue 3: European Microwave Week 2011 , June 2012 , pp. 349 - 355
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2012

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References

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