The conventional procedures of nondestructive evaluation by means of ultrasonic techniques are limited by surface roughness and grain-boundary scattering of testmaterials. Especially ceramics must be coupled carefully with high-frequency ultrasonic transducers. Concerning these restrictions and in view of the possibility of contactless measurements of low-loss dielectric materials with microwaves, the application of electromagnetic waves in NDE appears to be a favourable alternative to conventional ultrasonic techniques [1].