A New Method for Measuring the Electrical Properties of Sea Water and Wet Earth at Microwave Frequencies

By replacing the outer conductor of a section of 50-Ω coaxial line with a conductive material, the complex permittivity (dielectric constant and conductivity) of the material is determined from calculations based upon attenuation and phase shift measurements. The method is most accurate for materials with loss tangent greater than about 0.1 and conductivity around 1 mho/m or greater, such as sea water and highly conductive earth. Measurements made using NaCl solutions are in good agreement with published data.