Potential of superconducting films and filters for wireless applications.

Although many fundamental physics questions are still unanswered, the technology of high-temperature superconductors (HTSs) has become mature for use in wireless communications. In particular, superconducting filters utilizing HTS epitaxial films can provide better interference rejection, full use of the available frequency spectrum, decrease in the noise floor and size and weight reduction in receiver subsystems. A comparison of the microwave properties between films of high-T[sub c] superconductors YBa[sub 2]Cu[sub 3]O[sub 7-delta] and Tl[sub 2]Ba[sub 2]CaCu[sub 2]O[sub 8] and medium-T[sub c] superconductor Nb[sub 3]Sn is reported. A first prototype of a superconducting bandpass filter designed to handle a high circulating power and spanning the frequency range from 1710 to 1785 MHz is presented. The implications of its insertion in cellular base stations are discussed. [ABSTRACT FROM AUTHOR]