DIELECTRIC FILTER

摘要

A dielectric filter having excellent spurious suppression characteristics is disclosed. To avoid degradation of filtering characteristics caused by generation of spurious radiation, namely, high-level unwanted resonance oscillation in the passing band at the same frequency as that used for a mobile telephone in a microwave range, at least two types of dielectric resonators are combined and arranged in spaces separated by a partition wall inside a shielded body comprising a metal case and a metal cover, wherein the resonators have mutually different frequency characteristics in an unwanted harmonic mode other than the main mode in the vicinity of the passing band of the filter.