Automatic technique for the characterisation of a dielectric resonator coupled to a microstrip line

An automatic computer controlled technique is proposed to measure the resonant frequency, loaded quality factor and coupling factor of a dielectric resonator coupled to a microstrip line. The complex transmission coefficient of the system is measured, as a function of frequency, by means of a network analyzer. At each frequency, the reflection coefficient is calculated and its magnitude is processed to obtain the characteristic parameters of the resonator. Estimated errors for Q- and coupling factors are in the order of 1% and for the resonance frequency are about 1 part in 106.