محمد كياني

This thesis proposes five new measurement systems for extracting the effective electromagnetic characteristics of complex environments. In the first chapter, a summary of the thesis proposal is presented. The second chapter introduces the research conducted in the field of measuring the effective electromagnetic parameters of complex media. In the third chapter, we propose a new method based on changing the incident angle to extract the properties of lossy and dispersive inhomogeneous materials in free space. In the fourth chapter, a new measurement system is introduced for the experimental reconstruction of the inhomogeneity profile of materials loaded in a rectangular waveguide based on the change in the waveguide width. In the fifth chapter, the method of changing the width of the waveguide is extended to a non-destructive single-port configuration for the measurement of both electrical and magnetic properties of materials. In the sixth chapter, we propose a novel waveguide method for microwave characterization of biaxial materials. In this method, for the first time, we used the TM11 mode as an incident field to resolve the problem of preparing multiple samples and placing them in different orientations. In the seventh chapter, the method of changing the sample width is proposed to reconstruct the inhomogeneity profile of the electromagnetic parameters. In the eighth chapter, a novel measurement system is proposed based on combining sample width change and TM11 mode excitation for experimental eva‎luations of biaxial materials. The measurement systems proposed in the seventh and eighth chapters of the thesis, which are based on the partial filling configuration of the sample at the waveguide aperture, have solved the problem of fabricating multiple waveguides and multiple time calibrations that existed in the methods presented in the fourth and sixth chapters. The validity of all the proposed systems is experimentally verified by comparing the valid and previously used methods in the literature. In the ninth chapter, solutions for completing the activities carried out in this thesis and new topics that can be investigated in future works are suggested.

محيطهاي پيچيده الكترومغناطيسي , اندازه گيري مايكروويو , اندازه گيري مشخصات الكترومغناطيسي , نظريه الكترومغناطيس , پراكندگي مستقيم و معكوس در الكترومغناطيس مهندسي

Electromagnetic complex media , microwave measurement , measurement of effective electromagnetic parameters , electromagnetic theory , electromagnetic forward and inverse scattering problem

ali abdolali

majid tayarani