Two-resonator method for measurement of dielectric constant anisotropy in multi-layer thin films, substrates and antenna radomes

Two-resonator method, based on TE.,,-mode and TM,,,-mode resonance cavities with multi-layer disk sample is developed for measurement of longitudinal and transversal dielectric constant of each layer or in the whole sample averaging layer contribution. Dispersion equations for the considered modes in the both types of cavities with three, two or one-layer samples are obtained and measuring sensitivity and errors are discussed. Three practical examples are given for illustration of dielectric anisotropy determination in multi-layer samples: three-layer honeycomb antenna radome, thin nano-particle absorbing films on polyester sheets and one-layer reinforced substrates with penetrated woven glass cloth and fdling plastics or powders.