A semi double-ridged quasi TE-waveguide based microwave bulk material characterization system

Accurate microwave material characterization is essential for reliable high frequency circuit design. Therefore, various characterization techniques have been developed, comprising advantages and drawbacks for the respective conditions. In this paper, a material characterization system is presented, which enables a broadband measurement for both dielectric loss and relative permittivity of bulk substrates with variant geometrical dimensions. Strips of different dielectric bulk materials under test (MUTs) are mounted on top of an open semi double-ridged waveguide. Differential phase and amplitude broadband measurements with the MUTs are performed by a vector network analyzer, providing information on the introduced change in electrical length and dampening. The combined evaluation by measurement and electromagnetic simulations allow broadband assignments of the complex permittivity to the MUTs.