Band elimination filter

PROBLEM TO BE SOLVED: To provide a band-stop filter, having sufficient electric power resistance applicable to a filter for a transmitter used for a radio base station of a portable telephone. SOLUTION: The band-stop filter has a dual-mode resonator including a disk type resonance pattern. A first transmission line passes farther than the outside of the outer circumferential line of the resonance pattern and is electrically connected to the resonance pattern. A second transmission line is electrically connected to the resonance pattern at a first end part. A resonance signal excited by a signal transmitted in the first transmission line to the dual mode resonator is extracted to the second transmission line. COPYRIGHT: (C)2011,JPO&INPIT