A New Technique For Estimating The Transverse Dielectric Constant Of Laminated Microwave Materials

A new technique has been developed well suited to estimate the real part of the transverse dielectric constant of laminated microwave materials. Variations in the transverse dielectric constant influence the performance of circuits and antennas for which the electric field components parallel to the laminate surface are not negligible (e.g. suspended microstrip lines (SMLs) employed in the sandwich wire antenna (SWA)). The technique is based on the correlation between phase measurements on samples of the material in a waveguide using a vector network analyzer (VNA) and analytical formulas or finite element method (FEM) simulations. The technique has been verified to provide test results which correlate quite well with resonant methods based on cavity perturbation techniques