Accurate full wave estimation of quality factor and resonance frequency of HTS microstrip resonator

CAD Analysis of HTS Microstrip Patch Antenna Using a Spectral Domain Method

“…In the analysis, entire domain basis functions as given in Pozar (1982) have been used with the numbers of expansion mode N x = 1 and N y = 0. The thermal effects on the MSA characteristics has been incorporated through the temperature variations in the complex surface impedance, (1), and by including the effect of the thermal expansion of the LaAlO 3 substrate (Kedar et al, 2002) on the dimensions of MSAs. The analysis is carried over the temperature range 10 K to 0.9 T c , where T c is the transition temperature of the HTS film.…”

“…In (1), p is the fitting parameter whose value has been varied from 1 to 4 to obtain the best fit of R s and X s with the experimentally observed results. The surface resistance R s and surface reactance X s are inferred from the measured changes in the unloaded Q-value, 3 db bandwidth, insertion loss, and resonant frequency with temperature (Kedar et al, 2002;Misra et al, 2001). The value of p as 1.65 gives the best fit.…”

“…Kedar et al impedance matrix was modified to include diagonal metallic terms equal to sheet resistance R = 1/σ t. Kuo and Itoh (1991) used the same method to analyze a microstrip line using pulse basis functions. In our earlier publication (Kedar et al, 2002), microstrip resonators were analyzed using the SDM, in which the diagonal terms of Green's dyadic impedance matrix were modified by including the temperature-dependent complex surface impedance of the HTS leading to accurate estimation of resonant frequency and quality factor of microstrip resonator.…”

Efficient analysis for nonlinear microwave characteristics of high-power HTS thin film microstrip resonators

“…where Gij s are the Fourier transformed dyadic Green functions, α n and β are the Fourier transform variables and ω (=2π f ) is the angular frequency. In the formulation, finite conductivity and finite thickness of the HTS strip are accounted for by incorporating the complex impedance, Z s , as shown in (1) [9,10]. The detailed formulation of Z s is discussed in the following subsections.…”

“…In this paper, a comprehensive study of the nonlinear phenomenon of HTS microwave devices at moderately high power using a full-wave method is presented. The technique used is the spectral domain method (SDM) in conjunction with a complex resistive boundary condition [9,10]. The nonlinear model of complex surface impedance is presented by modifying the existing Vendik phenomenological model [11], to account for the nonlinear power dependence of the complex surface impedance on the RF magnetic field.…”