A simple algorithm for reliably determining the Q-factor of an open dielectric resonator made of a material with a tgδ less than 0.0001 in the shielded region is presented, based on measuring the parameters of an electromagnetically coupled system of bulk metal and open dielectric resonators. The analytical substantiation of the considered method for determining the Q-factor of an open dielectric resonator in electrodynamic and electrotechnical representations is carried out. The variants of the influence of the metal volume on the effective Q-factor of an open dielectric resonator depending on its electrophysical characteristics are considered. The factors affecting the effective Q-factor of an open dielectric resonator obtained using this measurement method are evaluated, and the range of expected measurement errors is shown. The advantage of the method for determining the Q-factor of an open dielectric resonator is the high accuracy of the obtained analytical ratios for determining the Q-factor, the absence of increased requirements for the accuracy of the measurement sections and the quality of the internal surfaces of the metal resonator, the simplicity of the measurement process, based on the use of ordinary equipment and element base.
