| 摘要 |
PROBLEM TO BE SOLVED: To provide a signal switching device which is capable of transmitting signals with small loss while satisfactorily securing isolation characteristics and does not require connection of a switch element to an output. SOLUTION: The signal switching device outputs an output signal from a desired transmission path out of a plurality of transmission paths coupled to an input path. The signal switching device has: a first variable impedance circuit having a first line which is connected in series to a first transmission path and is made of a superconducting material; and a second variable impedance circuit having a second line which is connected in parallel to a second transmission path and is made of a superconducting material. The cross-section of the second line is smaller than that of the second transmission path. The length of the second transmission path is determined in such a way that an input impedance to the second transmission path from the branch point of the first and second transmission paths is larger than a prescribed value when the second path is in a superconducting state. COPYRIGHT: (C)2004,JPO&NCIPI |
