The principle of the superconducting filter

Abstract

This study reviews the following issues in relation to the principle of the superconducting filter.　(1) The type of superconducting filter and its design method. (2) Future developments of the superconducting filter. (3) Applications of the superconducting filter. (4) Characteristics for the next-generation superconducting filter. Regarding the design of the filter, the technique using the equivalent circuit is described. Regarding the filter’s application, a band-pass filter system for a base station in the United States is described, and also we discuss the reasons why a superconducting filter system is necessary.