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.