and Time Domain Reflectometry Applications

and Time Domain Reflectometry Applications

Dennis Trebbels (Autor)
Broadband Measurement Techniques for Impedance
Spectroscopy- and Time Domain Reflectometry Applications
https://cuvillier.de/de/shop/publications/6329
Copyright:
Cuvillier Verlag, Inhaberin Annette Jentzsch-Cuvillier, Nonnenstieg 8, 37075 Göttingen, Germany
Telefon: +49 (0)551 54724-0, E-Mail: [email protected], Website: https://cuvillier.de
Contents
List of Figures
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List of Publications
vii
Zusammenfassung
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Abstract
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1 Introduction
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1.1 Impedance Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2 Impedance Spectra Representation . . . . . . . . . . . . . . . . . . . . . . 4
1.3 Broadband Measurement Signals . . . . . . . . . . . . . . . . . . . . . . . 6
1.4 Laboratory Measurement Equipment . . . . . . . . . . . . . . . . . . . . . 10
1.5 Electrode Configurations and Interfacing . . . . . . . . . . . . . . . . . . 11
1.6 State of the Art in Impedance Spectroscopy Measurement Circuits and
Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2 Biomedical Applications
2.1 Physiological Background . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Hematocrit Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.1 Introduction to Hematocrit Measurement . . . . . . . . . . . . . .
2.2.2 Existing Measurement Techniques . . . . . . . . . . . . . . . . . .
2.2.3 New Capacitive System Concept . . . . . . . . . . . . . . . . . . .
2.2.4 Finite Element Method Simulation . . . . . . . . . . . . . . . . . .
2.2.5 Sensor Prototypes . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.6 Laboratory Measurement Setup . . . . . . . . . . . . . . . . . . . .
2.2.7 Hematocrit Measurement Results . . . . . . . . . . . . . . . . . .
2.2.8 Temperature Drift Measurement . . . . . . . . . . . . . . . . . . .
2.2.9 Measurement at different Flow Rates . . . . . . . . . . . . . . . . .
2.2.10 Analysis and Discussion of Measurement Results . . . . . . . . . .
2.2.11 Summary and Conclusions . . . . . . . . . . . . . . . . . . . . . . .
2.3 Tissue Discrimination for Needle and Cannula Guidance . . . . . . . . . .
2.3.1 Introduction and Overview . . . . . . . . . . . . . . . . . . . . . .
2.3.2 Existing Needle Guidance Methods . . . . . . . . . . . . . . . . . .
2.3.3 Needle Guidance based on Step-Pulse Measurements . . . . . . . .
2.3.4 FEM Simulation of a solid Coaxial Needle . . . . . . . . . . . . . .
2.3.5 Laboratory Measurements with a solid Coaxial Needle . . . . . . .
2.3.6 Conclusions for the Step-Pulse Signal based Coaxial Needle Concept
2.3.7 Improved System Concept and Model for a Coaxial Cannula . . . .
2.3.8 FEM Simulation of the hollow Coaxial Cannula Tip . . . . . . . .
2.3.9 Chirp Measurement Signals and Processing . . . . . . . . . . . . .
2.3.10 Laboratory Measurement Setup . . . . . . . . . . . . . . . . . . . .
2.3.11 Description of Laboratory Experiments . . . . . . . . . . . . . . . .
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Contents
2.3.12
2.3.13
2.3.14
2.3.15
Measurement Results . . .
Evaluation and Discussion
Tissue Classification . . .
Conclusions . . . . . . . .
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3 Time Domain Reflectometry Applications for Moisture Measurement
3.1 State of the Art in TDR-Moisture-Measurement . . . . . . . . . . .
3.2 Moisture Detection in Buildings . . . . . . . . . . . . . . . . . . . .
3.2.1 Problem Description and proposed Solution . . . . . . . . .
3.2.2 Laboratory Experiments and Measurement Results . . . . .
3.2.3 Installation of a TDR Measurement System in a Building .
3.3 Groundwater Monitoring . . . . . . . . . . . . . . . . . . . . . . . .
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4 Broadband Measurement Electronics
4.1 Miniaturized Time Domain Reflectometer . . . . . . . . . . . . . .
4.1.1 System Concept . . . . . . . . . . . . . . . . . . . . . . . .
4.1.2 Sampling Concept . . . . . . . . . . . . . . . . . . . . . . .
4.1.3 Electronic Circuit . . . . . . . . . . . . . . . . . . . . . . . .
4.1.4 Laboratory Experiments . . . . . . . . . . . . . . . . . . . .
4.1.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 High Precision Phase Measurement . . . . . . . . . . . . . . . . . .
4.2.1 Overview and Target Application . . . . . . . . . . . . . . .
4.2.2 State of the Art in Broadband Phase Measurement Circuits
4.2.3 Delta Modulator based Sampling Circuit Concept . . . . . .
4.2.4 Sampling Concept for Low and High Frequency Signals . . .
4.2.5 Prototype Circuit and Test Results . . . . . . . . . . . . . .
4.2.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3 Fast Chirp Signal based Impedance Measurement Platform . . . .
4.3.1 Potential Target Applications for fast broadband Impedance
surement . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3.2 System Concept for measuring with Chirp Signals . . . . .
4.3.3 Signal Processing of the Chirp Signals . . . . . . . . . . . .
4.3.4 Prototype Circuits and Test Measurements . . . . . . . . .
4.3.5 Discussion and Conclusions . . . . . . . . . . . . . . . . . .
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5 Conclusions of the Thesis and Outlook
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List of Abbreviations
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Bibliography
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