US 6,549,093 B2 · Dielectric filter, duplexer, and communication apparatus incorporating the same

Abstract

A dielectric filter in which many attenuation poles can be generated, including attenuation poles generated by tap coupling, so that arbitrary passing characteristics and attenuation characteristics can be obtained. In this filter, inside a dielectric block there are formed through-holes having stepped structures in which inner conductors are disposed on the inner surfaces of the holes to capacitively couple the resonators. There are also formed lateral holes having conductive films disposed on the inner surfaces of the holes. The lateral holes are connected to input/output terminals in predetermined positions of the inner conductors. Further, terminal electrodes may be disposed adjacent to predetermined positions of the inner conductors. With this arrangement, attenuation poles are generated by both distributed constant resonator coupling and tap coupling on the low frequency side and/or the high frequency side of a pass band.

Claims13

Dependent claims

A dielectric filter comprising:

a dielectric member;
a ground electrode and a plurality of resonance lines formed on the dielectric member, the plurality of resonance lines forming a filter having a pass band;
and
input/output conductors tap-coupled with corresponding ones of the resonance lines;
wherein at least two of the resonance lines are disposed adjacent to each other, the at least two adjacent resonance lines being coupled to each other at respective ends thereof to provide distributed constant resonator coupling so that a first attenuation pole is generated on one of the high frequency side and the low frequency side of the pass band, and the tap coupling provides a second attenuation pole on one of the high frequency side and the low frequency side of the pass band.

2 more elements

Dependencies are inferred from the claim text.

Dielectric filter, duplexer, and communication apparatus incorporating the same

Life of this patent

Dielectric filter, duplexer, and communication apparatus incorporating the same

Life of this patent

Abstract

Claims13