A new single stepped-iris waveguide technique is used to nondestructively determine the permittivity and permeability of conductor-backed media. This thesis will demonstrate a proof-of-concept that obtains two independent reflection measurements with a magnetic radar absorbing material. Using, experimental method, a two measurement procedure in which the first measurement, will apply a single rectangular waveguide to a known conductor-backed magnetic radar absorbing material under test. Second measurement, will insert a stepped-iris (symmetrical) in between the single rectangular waveguide and conductor-backed material under test thus, reducing the aperture, in height, to retrieve two independent electromagnetic properties (i.e. permittivity and permeability). The theoretical reflection coefficient are obtained using a rigorous full-wave solution combined with a mode matching method at the waveguide and iris regions. Additionally, a root search algorithm is used to extract electromagnetic properties of magnetic radar absorbing material by comparing the theoretical and experimentally measured reflection coefficients. The experimental measurements of a commercial magnetic radar absorbing material measured by network analyzer will demonstrate the feasibility of the stepped-iris approach. Plots of the extracted permittivity and permeability of the material under test are analyzed to validate the stepped-iris material characterization technique.
展开▼
