Other

Sanyo Electric Co., Ltd.

Takaaki Uchiyama

Kenichi Ezaki

Katsumi Umeda

Masahisa Nakaguchi

The invention provides a dielectric filter device comprising a first electrode formed on a dielectric block for connection to an antenna, and a second electrode formed on an upper surface of the block for connection to a communications device, openings of hollow bores being arranged between the first and second electrodes to provide a filter for passing a predetermined frequency band, a plurality of hollow bores being arranged between the second electrode and a side surface of the block to provide traps having a plurality of attenuation poles. Attenuation of frequencies in the pass band can be diminished without providing an external circuit.

Dielectric filter device having perpendicular bores for improved pass band characteristics

The invention provides a dielectric filter device having first bore opening portions arranged between a first electrode formed on an upper surface or side surface of a dielectric block and a second electrode formed on the upper surface to provide a filter for passing a predetermined frequency band, and a second bore opening portion disposed between the second electrode and the side surface of the block. A conductive layer on the outer peripheral side surface close to the second electrode is removed in the form of a strip from at least one portion of the peripheral side surface which portion extends from the upper surface to the lower surface of the block. Unnecessary resonance in a high frequency range outside the pass band can be suppressed without providing an external circuit.

Dielectric filter device having conductive strip removed for improved filter characteristics

A coaxial resonator which can be electrically connected to an inductance or similar electric element easily to reduce the number of work steps for mounting and the number of parts, and a dielectric filter and a dielectric duplexer which include a resonator and which can be more compact and installed in a diminished space. The coaxial resonator includes a dielectric block having a through-bore extending through opposite end faces thereof, and a conductor layer formed over an outer peripheral surface of the block except one end face thereof and over a block inner surface defining the through-bore for causing electromagnetic waves to resonate within the dielectric block. A lead-equipped electric element has its lead inserted in and fixed in the through-bore and electrically connected to the conductor layer over the bore-defining inner surface with a braze filler metal or electrically conductive adhesive.

Coaxial resonator, and dielectric filter and dielectric duplexer comprising same

A polar band-pass dielectric filter including three coaxial dielectric resonators each including a main body in the form of a dielectric member, the main body being formed with a through bore extending through opposite end faces thereof, the main body having an outer conductor layer provided over an outer peripheral surface thereof and an inner conductor layer over an inner surface thereof defining the through bore. The resonators are joined to one another with one side of an outer periphery surface of each resonator serving as a joint surface. Each of the resonators has an electrode insulated from the outer conductor layer and provided at a portion of the outer peripheral surface thereof other than the joint surface. The electrodes of the resonators are connected together by a substantially straight conductor member.

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Higashiosaka, Japan

Takaaki Uchiyama