Six-port Complex Permittivity Measurements

This paper describes a new method of measuring the complex relative permittivity epsiv* of high-loss and low-loss materials up to the L-band in the microwave range, based on the six-port technique. The novel feature of this method is the determination of epsiv* directly from the intersection of three circles in the complex epsiv*-plane. This implies that neither liquids nor granulated materials are used as calibration standards; instead, conventional loads are employed. Furthermore, the ambiguity usually found in the phase of S₂₁ and reported in several methods is completely eliminated by the already consolidated six-port technique. Measured results are here presented for a high-loss material