Automatic measurement of resonator characteristics for determination of the electronic and magnetic properties of materials

Abstract

An automatic method for measurement of the resonant frequency and Q-factor of an X-band cavity microwave resonator is described. Results obtained, under computer control, for cavities with a Q-factor of up to 8000 are presented, and values of permittivity and conductivity measured on a number of materials are reported.

A computer-assisted method forQ-factor measurement of dielectric resonators

“…The experimental system used in measurement of Q 0 , as shown in figure 1, utilizes an X-band linear voltage-controlled oscillator (VCO) which can be easily programmed and calibrated (Al Zoubi and Al Dmour 1993).…”

“…For each resonator, the mean value of Q was obtained from 12 independent measurements performed during a period of 1 week in order to include errors due to apparatus calibration, temperature-stability effects and VCO linearity. The values of the Q factor and coupling coefficient β are given in table 1 together with those Measurements on waveguide resonators usually implemented in the measurement of mobility (Al Zoubi et al 1991, Al Zoubi 1991, permittivity and conductivity (Al Zoubi and Al Dmour 1993) have also been carried out and the mean Q values for 12 independent measurements together with the standard deviations (σ ) are shown in table 2. The proposed method, although it agrees closely with other sweep methods which follow similar operational principles and may be amenable to automation, is, however, more accurate.…”