Application of perturbation technique for measuring the dielectric constant of some liquids

In this paper, the measurements of dielectric constant of some liquids carried out in the X-band of the microwave spectrum are reported. A Gunn flange together with three cavities have been constructed with suitable holes for sample insertion. The theoretical analysis of the perturbation theory concerning the modified cavity-controlled oscillator is given and experimental measurements of the frequency shift for each designed cavity is presented. A comparison is achieved between the four positions of the cavity from which the optimum cavity position is selected. Finally, limitations of this method are represented.[PUBLICATION ABSTRACT]