Dielectric resonator and filter including capacitor electrodes on a

Abstract

A dielectric resonator includes a dielectric block having an open surface at one of the surfaces thereof, the remaining surfaces being plated with a conductor. The dielectric block has an inner conductor hole formed at a surface of the dielectric block opposite to the open surface, the inner conductor hole extending a predetermined depth toward the open surface such that it does not perforate through the open surface. An electrode pattern is formed on the open surface such that it faces an end surface of the inner conductor hole, the electrode pattern being adapted to provide an input/output capacitor. The dielectric block has a coupling window formed on a predetermined portion of one of the surfaces of the dielectric block, except for the open surface and the surface formed with the inner conductor hole, at a position adjacent to one of the open surface and the surface formed with the inner conductor hole. The coupling window is free of the plated conductor and adapted to control a coupling degree of the resonator to another resonator. Other embodiments include integral type filters having resonators in a single dielectric block.