Complex Permittivity of Sand at Low Frequency

This study was performed to identify the presence of measurement distortions such as electrode polarization and to investigate the influence of soil water content on complex permittivity at low frequency. In low frequency measurement using two-terminal electrode system, electrode polarization effect was observed at frequencies less than approximately 100 HBz. The analysis for real permittivity should be performed at frequencies above 100 kHz in order to exclude electrode polarization effect in the analysis of real permittivity at low frequency measurements. For a given soil, both of real and effective imaginary permittivity of wet soil increased continuously with volumetric water content. This is evidenced by the facts that the real permittivity is proportional to the number of dipole moments per unit volume and effective imaginary permittivity is effected by the conduction due to water. However, proportional relation between real permittivity and volumetric water content is valid at upper MHz frequencies.