Dielectric measurements by utilizing the curvature of pulses

This study shows that it is possible to utilize the curvature of pulses in order to measure the dielectric constant of materials. Calculation formulas are developed based on changes of the curvature of a pulse reflected by a shorted or open-circuited transmission line loaded with the dielectric, and a measurement procedure which utilizes the formulas is described. The formulas are most applicable for dielectrics with characteristics which vary slowly with frequency. They show that the dielectric constant can be expressed by means of the curvature and the time delay in the dielectric. Practical measurements of fresh water and crude oil were carried out. These media have completely different dielectric characteristics, but the calculation formulas give convincing results for both liquids. The accuracy of the measurements increases with increasing dielectric constant.<
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