Very narrow band HTS filters without tuning for UMTS communications

This paper present a High Temperature Superconducting (HTS) bandpass filter for Universal Mobile Telecommunication System (UMTS). For this application, filters cover the frequency range of 1920 - 1980 MHz and have a fractional bandwidth around 0,5 % and a good rejection at the transmit band. The aim is to realize the filter without tuning using double side YBCO thin film on MgO substrate of size 0,5 x 45 x 11,26 mm. In demonstration, a 10-pole Tchebyshev filter is fabricated and measured without tuning screw and the realization of a 10-pole quasi-elliptic filter is in progress.