Publication

Abstract : The study of the choice of transmission line for inspecting engineered dielectric composites is investigated here using open ended coaxial transmission line and waveguide operating in microwave regime. Wide band swept frequency measurements of the material under test (MUT) obtained using an open ended coaxial probe were used to identify the resonant frequency of the MUT. Material measurements gathered near and off the resonant frequency using an open ended coaxial probe and rectangular waveguide were analyzed to study the influence of the transmission line and the operating frequency for volumetric sensing of buried defects in fiber glass epoxy samples. Results indicate that open ended coaxial transmission line help identify the resonance frequency of the MUT and are well suited for volumetric inspection of thin dielectric composites with small defects due to their small footprint for an ultra-wide frequency band.