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Time-domain free-field measurements comprised the dielectric properties of several common building materials using dual-ridged guide antennas and 1 m × 1 m samples placed on an optical table covered with an absorber. The samples are poly-carbonate, gypsum, plywood, a brick wall, and a concrete wall. Time gating and deconvolution are used to isolate a sample's front and back surfaces to obtain the measured reflection coefficients (RCs) and transmission coefficients. Theoretical reflection and transmission equations were generated from a plane-wave model. Relative permittivity is obtained by varying the parameters in the Kirkwood-Fuoss equation until a best fit between the theoretical and measured reflection and transmission coefficients is obtained. [ABSTRACT FROM AUTHOR]

Presents complex permittivity data at microwave frequencies for many common plastics over a temperature range of 122 to 375 K. Tool used for the measurements; Manufacturing uses of plastics.

Analyzes ion relaxation around a charged electrode taking into account finite ion volume and frequency. Differential equations for time-dependent scalar and vector potentials in the Lorentz gauge; Development of the charge concentration using a drift-diffusion equation; Potential equations at low frequencies; Description of the modified Poisson-Boltzmann equation with excluded volume.

Presents a comparison between techniques used for the dielectric characterization of low-loss electrical materials. Reference to resonant methods used to obtain permittivity of low-loss materials; Discussion on the uncertainties associated with each method; Description of the field orientation method used to measure anisotropic materials; Information on a split-post resonator.