Wideband dielectric characterization using a dielectric filled cavity adapted to the end of a transmission line

The concept, analysis, and testing of a technique for characterizing dielectric materials over a wide band of frequencies are presented. The technique utilizes a cylindrical cavity completely filled with a sample of the dielectric material under test and adapted to the end of the precision air line. The complex permittivity of the filling dielectric is derived from the measured reflection coefficient. This technique offers great advantages over conventional methods where the sample is placed in a resonant cavity or inserted in a transmission line