Wideband Microwave Materials Characterization

1 Introduction to Electromagnetic Materials Properties

1.1 Dielectric Properties

1.2 Magnetic Properties

1.3 Dispersion

1.4 Anisotropy

1.5 Engineered Materials

1.6 Chapter 1 References

2 Free Space Methods

2.1 Historical Perspective

2.2 Calibration

2.2.1 One-Parameter Calibration

2.2.2 Four-Parameter Calibration

2.3 Time Domain Processing

2.4 Inverting Intrinsic Properties

2.4.1 Microwave Network Analysis

2.4.2 Nicolson-Ross-Weir (NRW) Algorithm

2.4.3 Iterative Algorithm – S11 or S21

2.4.4 Iterative Algorithm – S11 and S21

2.4.5 Iterative Algorithm – Shorted S11

2.4.6 Iterative Algorithm – Shorted S11 and S21

2.4.7 Iterative Algorithm – 4-Parameter

2.4.8 Inverting Sheet Impedance

2.5 Advanced Material Inversions

2.5.1 N-Layer Inversion

2.5.2 Two-Thickness Inversion

2.5.3 Model-Based Inversion

2.6 Absorber Characterization

2.7 Chapter 2 References

3 Microwave Non-Destructive Evaluation

3.1 Sensors / Antennas

3.2 Dealing with RF Cables

3.3 Thickness Inversions

3.4 Thickness and Property Inversion

3.5 Defect Detection

3.6 Chapter 3 References

4 Focused Beam Methods

4.1 Focused Beam System Design

4.1.1 Gaussian Beam Basics

4.1.2 Lens Design

4.1.3 ABCD Matrix Design

4.1.4 Lens System Construction

4.2 Focused Beam Measurement Examples

4.2.1 Dielectric Measurements

4.2.2 Magneto-Dielectric Measurements

4.3 Measurement Uncertainties

4.3.1 Transmission Line Errors

4.3.2 Focusing Error

4.3.3 Beam Shift Error

4.3.4 Specimen Position

4.3.5 Other Errors: Network Analyzer & Specimen

4.4 Apertures

4.5 Chapter 4 References

5 Transmission Line Methods

5.1 Waveguides

5.1.1 Waveguide Calibration

5.1.2 Waveguide Property Inversion

5.1.3 Waveguide Air Gap Correction

5.2 Coaxial Air Lines

5.2.1 Coaxial Calibration and Material Inversion

5.2.2 Air Gap Corrections in Coaxial Airlines

5.2.3 Wrapped Coaxial Airline Method

5.2.4 Square Coaxial Airline

5.3 Stripline Methods

5.4 Other Transmission Line Methods

5.5 Chapter 5 References

6 Scatter and Surface Waves

6.1 Diffuse Scatter

6.1.1 Radar Cross Section

6.1.2 Scattering Coefficient Measurement

6.1.3 Examples of Scattering Coefficient Measurement

6.1.4 Echo Width Measurement

6.1.5 Examples of Echo Width Measurement

6.1.6 Cross Polarized Scatter

6.2 Near-Field Probe Measurements

6.3 Surface Traveling Wave

6.3.1 Surface Wave Attenuation

6.3.2 Surface Wave Attenuation Measurement

6.3.3 Surface Wave Backscatter

6.3.4 Chapter 6 References

7 CEM-Based Methods

7.1 Computational Electromagnetic Modeling

7.2 CEM Inversion of Broadband Materials

7.3 CEM Inversion Example: RF Capacitor

7.3.1 RF Capacitor Design

7.3.2 RF Capacitor Uncertainty

7.3.3 Example Measurements

7.4 CEM Inversion Example: Non-Destructive Measurement Probes

7.4.1 Epsilon Measurement Probe

7.4.2 Mu Measurement Probe

7.5 CEM Inversion Example: Slotted Rectangular Coaxial Line

7.6 Chapter 7 References

8 Impedance Analysis and Related Methods

8.1 Impedance Analysis

8.2 Dielectric Spectroscopy

8.2.1 Dielectric Parameters

8.2.2 Electrode Fixtures

8.2.3 Error Sources

8.3 Dielectric Spectroscopy Applications

8.3.1 Polymer Physics

8.3.2 Cure and Process Monitoring

8.3.3 Film Formation and Environmental Effects

8.3.4 High Frequency Dielectric Analyses

8.4 Permeameter Methods

8.5 Chapter 8 References