Date of Award
3-2024
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Department of Electrical and Computer Engineering
First Advisor
Michael J. Havrilla, PhD
Abstract
Novel metamaterial and metasurface realizations provide unique control of the electromagnetic wave dispersion but present many challenges for accurate constitutive parameter extraction. One measurement approach commonly employed is a freespace non-destructive focus beam system. Modern implementations are configured with multi-static dual-polarized capabilities for characterizing complex materials and offer many advantages by enabling ultra-wideband sampling, multiple measurement degrees of freedom and larger sample sizes. Practical electromagnetic material characterization of complex bianisotropic media requires the advancement of wave propagation analysis and calibration schemes. This research focuses on generalized biaxial media characterization and multi-static focused beam system metrology with polarimetric calibration schemes and measurement standards. The fundamental analysis is developed to solve the forward model theory for general biaxial media based on eigenwave solutions from conventional and coordinate system transformation approaches. Theoretical scattering parameter expressions are identified for any excitation polarization and incidence angle. Then, a polarimetric self-calibration scheme for focus beam systems is developed using physically realizable metrology standards. Finally, the propagation theory and calibration schemes are validated with precision measurements and a revised measurement procedure for improved clutter subtraction. To support polarimetric calibration an ultra-wideband wire-grid polarizer measurement standard is developed based on manufacturing concepts from A-sandwich radomes. The polarimetric calibration techniques and measurement procedures are applicable to biaxial media as well as any general sample characterization.
AFIT Designator
AFIT-ENG-DS-24-M-019
Recommended Citation
Massman, Jeffrey P., "Generalized Characterization of Biaxial Media using Ultra-Wideband Multi-Static Focused Beam System with Polarimetric Calibration" (2024). Theses and Dissertations. 7782.
https://scholar.afit.edu/etd/7782
Comments
A 12-month embargo was observed for posting this work on AFIT Scholar.
Distribution Statement A, Approved for Public Release. PA case number on file.