Measurement of Sheet Dielectric Materials at UHF Band

One of the most important parameters of dielectrics is complex permittivity. Nowadays sheet dielectric materials are applied in different wireless technologies therefore knowledges about their properties are very important. Measurement of the permittivity is difficult issue for VHF and UHF ranges. Conventional methods are limited by extremely large size of the overall measurement set. Here we suggest a mathematical model for alternative approach based on a free-space measurement method. We have designed a similarity model of the Fabry-Perot resonator including only an antenna and a reflector.