Determining the complex permittivity and the complex permeability of magnetodielectric materials in the range of centimeter and decimeter waves

摘要

The relatively simple measuring methods for determinign the comple xpermittivity and the complex permeability of magnetodielectric materials are presented. Measurements must be done with each sample of any magnetodielectric by two methods: the short circuit metod and the idling method. For measurements by the short circuit method, a magnetodielectric sample is placed in the measuring waveguide near the short circuit end. For measurements by the idling method, a magnetodielectric sample is placed in the measuring waveguide at a quarter of the wavelength distance from the short circuit end. The measurements are taken equally for both methods. The measuring waveguide (with a sample) is connected to the standard measuring line. the other end of the measuring line is connected to a transmitter. A transmitter radiates waves of a given frequency, they are reflected by the short circuit end of a measuring waveguide containing a magnetodielectric sample and standing waves are set up Standing wave parameters can be measured by the standard measuring line and the indicator. The coefficient of the stading wave 1/ k and the displacement triangle openx of a minimum of the electric field intensity (due to decrease of the wavelength in a magnetodielectric sample) are measured by short circuit and idling methods. Both methods lead to the transcendental equaton which determines the complex wave propagation coefficient in a magnetodielectric sample as a function of a sample thickness, the wavelength, 1/k and triangle openx from both measuring methods. After that the complex permeability of the under investigation magnetodielectric is taken as a function of the complex wave propagation coefficient, a sample thickness, the wavelength, 1/k and triangle openx from both measuring methods. The complex permittivity of this magnetodielectric is taken as a function of the complex wave propagation coefficient, a thickness of a sample, the wavelength and the complex permeability.