Material characterization is the process of determining the electrical properties of a material by using knowledge of how electromagnetic waves reflect and transmit through a material sample. This characterization can be critical to the design of high-speed circuits and packaging, microwave remote sensing, bioengineering, food engineering, agriculture, and general materials science. An interesting problem within material characterization is the non-contact, non-destructive characterization of conductor-backed media. Conductor-backed media are materials which are directly adhered to a good or a perfect electric conductor (PEC). This scenario occurs in real-life applications such as the characterization of in-situ materials or characterization of shielding apparatus. For this specific case, reflection-only methods must be used because measurement of transmission properties is impossible due to the PEC backing.The main focus of this dissertation is the study of the strengths and weaknesses of various reflection-only material characterization methods by performing a thorough error analysis. More specifically, the propagation of measurement errors into extracted material parameters is investigated. Such analysis is lacking in the material characterization area. Key contributions of this research are (1) a general formulation for deriving reflection-only material characterization methods, (2) a general process for determining the propagated error into many reflection-only material characterization methods, (3) a method for characterizing conductor-backed media, (4) expanding the use of interval analysis in the electromagnetic community, and (5) determining the impact of wave curvature on free-space reflection-only material characterization methods.
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