Signal model to extract intrinsic parameters of high-Q dielectric resonators from noisy measurements

We report characterization of an open dielectric resonator with Q of 4000 to 7000 in the 25-40 GHz frequency range. Because of its small size, the measured parameters are very sensitive to background noise contributed by the coupling mechanism, package modes, radiation, etc. Therefore, it becomes important to properly calibrate out this parasitic influence in order to accurately measure the unloaded Q factor of the resonator. We report an accurate software calibration procedure based on a state-space spectral estimation algorithm, which effectively filters out the background noise and facilitates linear extraction of the unloaded Q