The Htsc Cmrc Design And Application In Microwave Devices, And Research

This paper presents the characteristics of HTSC(high temperature superconductivity) materials, the basical theory of microstrip circuit and the theory of HTSC filters.A CMRC(compact microstrip resonant cell) is designed with HTSC materials.It has the characteristics of PBG(photonic bandgap), slow-wave, bandgap and so on, and it has the advantage of reduce the size of microstrip resonator. Then the models of HTSC four-pole quasi-elliptic function filter were built by full-wave field solvers. And the HTSC quasi-elliptic function filter using CMRC according to the aim of designs is synthesized, manufactured, installed and measured. By this method, a six-pole quasi-elliptic function filter and three eight-pole quasi-eplliptic function filters were designed . In this paper, difficulties such as the design of HTSC microwave passive component,the lithography process technology, the encapsulation and the measurement in low temperature etc. are solved, One of three eight-pole filters having center frequency in 1.8 GHz and having a bandwidth of 100 MHz are manufactured and measured, at the centre frequency the measured return loss and insertion loss are 20 dB and 0.15 dB respectively,and out-band rejection is larger than 60 dB , 2f0 and 3f0 spectrum are successfully suppressed(where f0 is the midband frequency),and measurement results satisfied the requires of designs. The microwave filters using HTSC thin films have the advantages of low surface resistance, small in size and mass and high quality factor, so it's performances are much better than the filters using wave-guide, dielectric resonator or conventional planar structures, offers the potential of large reduction in mass and volume of communication systems.