Extracting the model parameters of high-temperature superconductor film microwave surface impedance from the experimental characteristics of resonators and filters

A procedure of extracting the model parameters of a high-temperature superc onductor (HTS) film from the experimental characteristics of resonators and filters is proposed. It is based on a correct phenomenological model of th e HTS film surface impedance and an accurate simulation of the filter (reso nator) structure by taking into account the temperature dependence of the d ielectric permittivity of the substrate and its thermal expansion coefficie nt. The experimental characteristics measured at different temperatures hav e to be used. The procedure was successfully applied, in order to extract t he HTS film parameters from the characteristics of a single hairpin microst rip resonator and an 11-pole hairpin-comb filter. The proposed procedure of extracting the model parameters seems suitable to be used at an earlier st age in the design of high-performance trimmingless HTS devices.