Murata Manufacturing Co., Ltd.

Murata Mfg. Co., Ltd.

Hideyuki Kato

Hitoshi Tada

Haruo Matsumoto

Jinsei Ishihara

Motoharu Hiroshima

Tatsuya Tsujiguchi

Yukihiro Kitaichi

Katsuhito Kuroda

Tadahiro Yorita

Yasuo Yamada

Hisashi Mori

Takahiro Okada

Jun Toda

Shohachi Nishijima

Hideki Tsukamoto

Takashi Maruyama

Hajime Suemasa

Hirohumi Miyamoto

Hiroshi Tada

Youhei Ishikawa

Masayuki Atokawa

Jun Hattori

Hirotsugu Mori

Toshio Nishikawa

Kikuo Tsunoda

Yuichi Kushihi

Hirofumi Miyamoto

Junichi Kurita

Yasunori Takei

Takayoshi Yui

A chip device having a ground electrode and a plurality of top-surface electrodes on a plate-like dielectric substrate. Two of the top-surface electrodes are connected to the ground electrode via respective short-circuit side-surface electrodes to form quarter wavelength resonant lines. A third top-surface electrode is provided between the two top-surface electrodes and both ends thereof are opened to form a half wavelength resonant line. The two top-surface electrodes each have a parallel portion arranged near and in parallel to the third top-surface electrode and a flexion that curves from the parallel portion, extends toward the remaining of the two top-surface electrodes, and is jump-coupled to the remaining of the two top-surface electrodes. The short-circuit side-surface electrodes are jump-coupled to each other, like the flexions.

Dielectric filter having electrodes jump-coupled to a flexion, a chip device having the dielectric filter and method of manufacturing the chip device

A balanced-unbalanced transformation device includes a plate-like dielectric substrate having a ground electrode and a plurality of major surface electrodes formed thereon. Two of the major surface electrodes are connected to the ground electrode via short-circuit side surface electrodes so as to form &#xbc; wavelength resonator transmission lines. A third major surface electrode is disposed between the two major surface electrodes and has either end open so as to form a &#xbd; wavelength resonator transmission line. A balancing characteristic adjustment side surface electrode is provided on a side surface of the dielectric substrate. By adjusting a capacitance formed between the balancing characteristic adjustment side surface electrode and the third major surface electrode, a phase balance between two balanced signals is set to a desired value.

Balanced-unbalanced transformation device and method for manufacturing balanced-unbalanced transformation device

A dielectric filter with an ultra hetero-axial structure is provided with open end-face electrodes. By increasing the capacitance between each open end-face electrode and an external conductor greater than that generated between the open end-face electrodes adjacent to each other, the inductive coupling between two resonators due to neighboring resonator holes is increased.

Dielectric filter, dielectric duplexer, and communication apparatus

A &#x3bb;/2 resonator comprises an inner conductor formed hole having an inner conductor with both open-ends, formed therein, and &#x3bb;/4 resonators comprise inner conductor formed holes having inner conductors with one short-circuited ends and the other open ends, respectively. The resonators are coupled, whereby a terminal electrode connected to the vicinity of the one open end of one of the &#x3bb;/4 resonators functions as an unbalanced terminal, and terminal electrodes connected to both open ends of the &#x3bb;/2 resonator function as balanced terminals.

A method of forming a dielectric resonator from an inner-conductor-formed hole that has a substantially rectangular or substantially elliptical cross section in a direction perpendicular to the depth direction thereof, by placing a rotary cutting disk in contact with the edge of the opening of the inner-conductor-formed hole, and removing portions of an outer conductor and the inner conductor in the contact portion with the rotary cutting disk, thereby separating the inner conductor and the outer conductor.

Production method for dielectric resonator device

In a dielectric filter, from the top surface to the bottom surface of a substantially rectangular dielectric block, inner-conductor holes are formed. On the inner surfaces of the inner-conductor holes, inner conductors are formed except where non-conductor portions are formed in proximity to one of the top and bottom surfaces, in which the apertures of the inner-conductor holes are formed. On the outer surface of the dielectric block, an outer conductor is formed substantially over the entire outer surface, and input and output electrodes isolated from the outer conductor are coupled with the non-conductor portions in the respective inner-conductor holes at the ends of the dielectric block in the direction of array of the inner-conductor holes. In one of the surfaces in which the apertures of the inner-conductor holes are formed, or in one of the surfaces at the ends of the dielectric block in the direction of array of the inner-conductor holes, a concavity is formed, the inner surface thereof being covered with the outer conductor.

The present invention provides a dielectric resonator, a dielectric filter, a dielectric duplexer capable of reducing leakage of electromagnetic waves and capable of being miniaturized, and a communication apparatus incorporating the same. In each of the dielectric resonator and filter, inside a dielectric block, there is formed a L-shaped inner-conductor-formed hole having a bend at some point of the hole in a manner extending from an outer surface of the dielectric block to a surface perpendicular to the outer surface. An inner conductor is formed on the inner surface of the inner-conductor-formed hole. On the substantially entire outer surfaces of the dielectric block, there is disposed an outer conductor, with one end of the inner-conductor-formed hole open-circuited and the remaining end of the hole short-circuited. Around the edge of the open-circuited end there is formed an outer coupling electrode. This structure enables formation of the dielectric resonator and the dielectric filter having the L-shaped inner-conductor-formed holes.

Dielectric resonator, dielectric filter, dielectric duplexer, and communication apparatus incorporating the same

A dielectric filter provided with a dielectric block including at least four resonant through holes that are adjacent to each other. A multipath slot is arranged near three adjacent through holes of the at least four resonant through holes. The multipath slot has an inner conductor formed on an inner surface thereof in order to generate a first capacitance between a first area near the open end of each of the three adjacent through holes and the inner conductor of the multipath slot. A step is formed so that a second capacitance is generated between a second area near the open end of each of two through holes of the at least four resonant through holes and an outer conductor located within the step. An attenuation peak is generated at the lower-frequency side of the passband with the multipath slot and the three adjacent through holes, and an attenuation peak is generated at the higher-frequency side of the passband with the two through holes and the outer conductor within the step.

A dielectric filter includes a dielectric block having a plurality of through holes; an outer conductor provided on an outer surface of the dielectric block; and inner conductors provided on inner surfaces of the plurality of through holes. The dielectric filter also includes a first dielectric provided between the respective inner conductors and the outer conductor; and at least one second dielectric provided between the inner conductors of two adjacent through holes. The temperature coefficient of the resonant frequency of the first dielectric is different from that of the second dielectric. If inductive coupling between the adjacent resonators generates an attenuation pole at a frequency higher than a pass band, the temperature coefficient of the resonant frequency of the first dielectrics is set to a predetermined positive value, and the temperature coefficient of the resonant frequency of the second dielectric is set to a predetermined negative value.

A dielectric filter and a dielectric duplexer have structures for coupling between resonators, in which a range for determining the coupling strength between the resonators can be broadened and the polarity of the coupling can be changed. In addition, a communication apparatus incorporating the dielectric filter or the dielectric duplexer can be provided. Inside a dielectric member, resonance line holes having resonance lines formed on the inner surfaces thereof are disposed. Both ends of each of the resonance line holes are open-circuited. The inner diameter of each of the resonance line holes is changed at some point in the longitudinal direction of each resonance line to form a stepped part.

Dielectric filter, dielectric duplexer, and communication apparatus incorporating the same

A dielectric filter including: a &lgr;/2 resonator for generating resonance of &frac12;-wavelength at a predetermined frequency, having both ends open-circuited or short-circuited; and a pair &lgr;/4 resonators respectively for generating resonance of &frac14;-wavelength at a frequency substantially equal to the predetermined frequency, each having one end open-circuited and the other end short-circuited; wherein the pair of &lgr;/4 resonators are disposed in proximity to each of both ends from the vicinity of the center of the &lgr;/2 resonator; a terminal coupling to the &lgr;/2 resonator is provided as an unbalanced terminal; and terminals coupling to the pair of &lgr;/4 resonators is used as a balanced terminal. In the above filter, the balanced-type input/output of signals can be performed without using a balun.

A dielectric filter capable of easily obtaining desired filter characteristics by strongly coupling mutually adjacent resonators with high accuracy even when reducing the height of the entire filter. In this filter, inside a dielectric block, there are disposed inner-conductor-formed holes in which inner conductors are formed on the inner surfaces of the holes. Coupling electrodes are arranged on an outer surface of the dielectric block and are electrically connected to the inner conductors. Additionally, the coupling electrodes are extended, for example, from the edge of an opening surface of the dielectric block which contains the open ends of the inner-conductor-formed holes, onto a side surface which is disposed parallel to a direction in which the inner-conductor-formed holes are aligned. The invention also provides a duplexer and a communication apparatus using the dielectric filter.

A dielectric filter includes a dielectric block having inner-conductor-formed holes extending from a first face of the dielectric block to a second face opposed to the first face. Inner conductors are formed inside the inner-conductor-formed holes such that both ends of the inner-conductor-formed holes are open-circuited. On the exterior surface of the dielectric block, balanced input/output terminals are capacitively coupled to the open ends of the inner-conductor-formed holes. A metal cover is provided so as to cover one of the first or second face of the dielectric block. The metal cover functions as a short-circuit conductor in a spurious mode such as a TE mode other than a TEM mode, and hence the influence of the spurious mode is avoided.

In a dielectric block, an array of three excitation holes, in each of which one opening is a short-circuited end and the other opening is an open-circuited end, are disposed so as to be interdigitally coupled and balanced input-output terminals are provided at the opening of the excitation holes at both ends of the array. A resonator hole is provided so as to be coupled to one excitation hole of the excitation holes at either end of the array. Thus, a compact dielectric filter with balanced input-output terminals is constructed.

Growing community of inventors

Ishikawa-ken, Japan

Hideyuki Kato