A broad-band measuring equipment for determining the complex permittivity of liquid dielectric materials within the frequency range of 1 MHz to 1 GHz

Abstract

A technique is presented to determine the complex permittivity epsilon = epsilon '-j epsilon " by means of a coaxial line set-up for transmission coefficient measurement within the frequency range of 1 to 1000 MHz. A highly sensitive broad-band vectorvoltmeter and dielectric sample cells of the cut-off variety enable precise measurements in a comparatively short time and ease of handling. The cells are designed for the investigation of weakly as well as highly polar liquid dielectrics. The relative error of the real part epsilon ' of the complex permittivity typically amounts to 1-2% and the absolute error of the dielectric loss angle up to 0.3 degrees .