Micro-Computer Controlled Moisture/Permittivity Measurements in Microwave Frequencies

A microwave system using close-loop technics measures simultaneously the weight and the complex dielectric constant of sample materials heated by strong electric RF fields inside a resonant cavity. The uses of a micro-computer permits to relate, in real time, the moisture content of sample materials exposed to RF fields to the dynamic changes observed in the complex dielectric constant at the test frequency [1].