Narrow-band 10-pole Y-Ba-Cu-O filter on sapphire substrate

ln tills paper we present the design procedure of HTS bandpass filters on s apphire substrate. The filter with 0.4% fractional bandwidth in S-band was designed using an effective CAD tool, based on spectral domain approach. Th e filter is based on hairpin resonators exhibiting unloaded Q up to 43000 a t T = 77 K. The anisotropy of the dielectric permittivity of sapphire subst rate and the YBCO film contribution in the propagating characteristics have been taken into account. Substrate characteristics and YBCO film model par ameters were extracted from microstrip and hairpin resonator measurements. These parameters were used in the filter simulation procedure.