Precise Dielectric Measurement Techniques for the Frequency Range 10 GHz to 150 GHz

Systems have been developed for the measurement of permittivity ε' and loss angle δ for low and medium loss liquids and solids. Closed cavities constructed from helix waveguide have been used at 10 GHz and 35 GHz. Open resonators using one plane and one concave mirror in the near hemispherical configuration have been used at 35 GHz, 72 GHz and 144 GHz. In general the accuracy obtainable with these systems is ± 0.1% for ε' and ± (1% + 1μrad) form δ. The accuracy tends to vary a little with operating frequency and technique of measurement.