DIELECTRIC FILTER, COMMUNICATION EQUIPMENT, AND METHOD OF CONTROLLING RESONANCE FREQUENCY

摘要

PROBLEM TO BE SOLVED: To provide a dielectric filter of low spurious characteristics in which a high frequency side attenuation quantity of a passband is sufficiently secured. SOLUTION: In the dielectric filter provided with: a metallic case 101 having an opening in its upper portion; a metallic lid 103 for closing the opening; a dielectric resonator 105 installed on the bottom surface inside of the case 101 via a supporting stand 104; a bolt 106 made from a dielectric material to be inserted at a position corresponding to the dielectric resonator 105 of the lid 103; and a metallic plate 107 installed in a terminal portion of the bolt 106 substantially parallel to an upper surface of the dielectric resonator 105, the position of the bolt 106 is adjusted to change an interval between the dielectric resonator 105 and the plate 107, thereby controlling the resonant frequency thereof. COPYRIGHT: (C)2004,JPO