The Resonant Linear Antenna as a Probe for Measuring the In Situ Electrical Properties of Geological Media.

摘要

A method is presented that uses the resonant linear antenna as a probe to measure the electrical properties of dissipative media. Parametric equations are derived for the length and driving point resistance of the antenna in terms of the relative permittivity and loss tangent of the ambient medium. Graphs constructed from these equations permit a simple determination of the electrical properties of the medium from the length and resistance at resonance. The application of the method to the measurement of the relative permittivity and loss tangent of in situ geological media is described. Calculations for different geological materials indicate that the method is particularly useful for making measurements with antennas of convenient length at frequencies in or near the VHF band. The method was tested experimentally by measuring the electrical properties of freshwater, saltwater solutions, and moist sand. The results of these measurements are discussed. (Author)