Complex permeability and permittivity and microwave absorption of ferrite-rubber composite at X-band frequencies

Abstract

The complex permeability ( mu /sub r/) and permittivity ( epsilon /sub r/) spectra at X-band frequencies and their relationship with microwave absorbing properties are investigated in ferrite-rubber composite material. Multifrequency measurements of mu /sub r/ and epsilon /sub r/ are made by the reflection/transmission technique. The theoretical determination of matching frequency and matching thickness and minimum reflection loss can be made by plotting the observed mu /sub r/ and epsilon /sub r/ spectra on the solution map of wave-impedance-matching. It is found that a proper combination of mu /sub r/ and epsilon /sub r/ is necessary to produce the zero-reflection absorber at a given frequency and thickness.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>