  A method for determining the permittivity and permeability for specimens with
high refractive index and variable shape is investigated. The method extracts
the permeability and permittivity tensor elements from reflection measurements
made with a partially-filled shorted rectangular waveguide on an electrically
small specimen. Measurements are performed for two isotropic, heavily loaded
coaxial magnetic composites. Supporting measurements from a stripline cavity
and coaxial airline are used to validate the method. The results demonstrate
the methods ability to handle frequency dispersive and high index materials.
