Cross-coupled HTS microstrip open-loop resonator filter on LAO substrate

This paper presents the recent investigation of implementing an 8-pole cross-coupled high temperature superconductor (HTS) microstrip open-loop resonator filter on an LaAlO/sub 3/ substrate for mobile communication applications. The filter was designed to have a pass band from 1770 to 1785 MHz, and fabricated using double sided YBCO thin film on a wafer of size 0.5/spl times/23.5/spl times/39 mm. A very encouraging performance has been achieved. The influence of unwanted cross couplings on the filter response, which is of importance for further development is addressed.