A versatile measurement system for the determination of dielectric parameters of various materials

In this paper, a versatile method for the determination of the complex permittivity of materials from measured scattering parameters is presented. The measurement set-up consists of a waveguide applicator for housing the material sample. The considered frequency range is 2?3 GHz. The complex scattering parameters are measured by a vector network analyser. The algorithm for computing the complex permittivity from the measured scattering parameters is shown in detail and an error estimation is performed. Depending on the waveguide layout liquid, granular and solid materials can be measured. To measure granular and liquid samples two dielectric walls inside the waveguide are used to house the samples. The dielectric parameters of different soils as well as of some liquids are determined with consideration of their moisture content and temperature. In contrast to several other techniques, this measurement set-up is also suited for high loss materials. The set-up has also been successfully used for measurements of anisotropic materials.