Murata Manufacturing Co., Ltd.

Tatsuya Tsujiguchi

Hideyuki Kato

Haruo Matsumoto

Hitoshi Tada

Yukihiro Kitaichi

Tadahiro Yorita

Hisashi Mori

Yasuo Yamada

Shigeji Arakawa

Takanori Uejima

Hiromichi Kitajima

Saneaki Ariumi

Hisao Hayafuji

Yasunori Takei

Satoshi Tanaka

Yutaka Sasaki

Satoshi Arayashiki

Hiroaki Tanaka

Motoharu Hiroshima

Munehisa Watanabe

Jin Yokoyama

Akio Kaneda

Kiwamu Sakano

Nobuyoshi Honda

Toru Yamaji

Junichi Yoshioka

Seima Kondo

Akihide Nakano

Hiroyuki Furusato

Atushi Ono

A transmit/receive module includes plural duplexers, a power amplifier, and a sending transmission line. The plural duplexers operate in bands different from each other and each includes a transmit filter and a receive filter. The power amplifier amplifies signals of pass bands of the plural transmit filters and outputs the amplified signals. The sending transmission line is connected to the plural transmit filters. The signals of the pass bands of the plural transmit filters output from the power amplifier are transmitted through the sending transmission line.

Transmit/receive module

A high-frequency front end circuit includes a duplexer, a phase adjustment circuit, and a power amplifier. The phase adjustment circuit is connected between the power amplifier and a transmission filter of the duplexer. The phase adjustment circuit carries out phase adjustment so that a quadrant in which an impedance ZRX (fr0) seen from the transmission filter toward the power amplifier at the fundamental frequency of a reception signal is present and a quadrant in which an impedance ZTX (fr0) seen from the power amplifier toward the transmission filter at the fundamental frequency of the reception signal is present are not in a conjugate relationship with respect to the phase.

High-frequency front end circuit

A radio frequency front-end circuit includes a duplexer, a phase adjustment circuit, and a low noise amplifier. The phase adjustment circuit is connected between an Rx filter of the duplexer and the low noise amplifier. The phase adjustment circuit executes phase adjustment such that a quadrant in which an impedance ZLNA(fn) at a particular frequency different from a fundamental frequency of a reception signal when looking at the low noise amplifier side from the Rx filter is present and a quadrant in which an impedance ZRX(fn) at the particular frequency when looking at the Rx filter side from the low noise amplifier is present are not in a conjugate relation in terms of phase.

Radio frequency front-end circuit

A stripline filter having a substrate, a grounding electrode, principal-surface lines, side-surface lines, and common electrodes, and is mounted on a set substrate by soldering. The side-surface lines are disposed on a side surface of the substrate, and are wetted by solder during soldering. Each of the common electrodes is connected to a corresponding one of the principal-surface lines. The common electrodes are also connected to the grounding electrode via the side-surface lines.

Stripline filter

The element size of a stripline filter that achieves a high efficiency percentage with optional stable filter characteristics, is reduced. A stripline filter includes substantially L-shaped top surface resonant lines. The top surface resonant lines include connection electrode parts, first line parts, and second line parts. The connection electrode parts are formed so as to have a width greater than line widths of side surface resonant lines. Each line part faces an edge of a corner portion of a central top surface resonant line at an interval. An edge of each first line part on an edge side of a dielectric substrate, other than a connection portion with the connection electrode part, faces an edge of the dielectric substrate at an interval.

Stripline filter and manufacturing method thereof

A filter element includes a flat dielectric substrate, a ground electrode on a back main surface of the dielectric substrate, resonant lines each having a shorting end in the vicinity of a border between a side of the dielectric substrate and the ground electrode and extending from the side to a front main surface of the dielectric substrate. The resonant lines and the ground electrode constitute strip-line resonators. In any of the strip-line resonators, the line width of the resonant-line side portion is different from the line width of the resonant-line main-surface portion.

Filter element and method for manufacturing the same

A dielectric resonator device includes a dielectric plate. An electrode is provided on each of both principal surfaces of the dielectric plate and a plurality of pairs of mutually-opposing electrode openings are formed in the electrodes. Accordingly, the dielectric resonator device functions as a three-stage resonator. Strip lines serving as input/output probes are provided on the upper surface of an input/output substrate. Also, a ground electrode having electrode openings are formed thereon. By providing the dielectric resonator device and an upper substrate on the upper surface of the input/output substrate, a dielectric filter is formed.

Dielectric resonator device, dielectric filter, dielectric duplexer, and communication apparatus

A flat group-delay low-pass filter includes a series element connected between an input terminal and an output terminal, and a shunt element with one end thereof grounded. Inductors define the series element, a parallel circuit including a capacitor and a series circuit including a resistor and a capacitor defines the shunt element. The flat group-delay low-pass filter thus eliminates the need for inserting a fixed attenuator to control the effect of reflections due to impedance mismatching between the filter and other components. The resulting flat group-delay low-pass filter and an optical signal receiver including the filter have very low manufacturing costs and component costs.

Flat group-delay low-pass filter, mounting structure thereof, flat group-delay low-pass filter device, and optical signal receiver

A lumped filter includes an input terminal, an output terminal, and a ground electrode disposed on a dielectric film on an alumina substrate. A first spiral inductor is connected between the input terminal and the ground electrode. A second spiral inductor is connected between the output terminal and the ground electrode. MIM capacitors are inserted between the input terminal and the first spiral inductor, and between the output terminal and the second spiral inductor. A third spiral inductor is inserted between the first and second spiral inductors. The spiral inductors have self-inductance, and capacitance between the spiral inductors and the electrodes adjacent thereto, by which the spiral inductors self-resonate and define as parallel LC resonators.

Lumped filter, shared antenna unit, and communication device

The invention provides a high frequency filter which can facilitate filter-characteristic adjustments and miniaturization and can obtain an excellent broadband characteristic. In addition, the invention provides a filter device using the high frequency filter, and an electronic apparatus incorporating the same. In this filter, a ground electrode is arranged on one of the main surfaces of a dielectric substrate. On the other main surface thereof there are arranged two or more microstrip lines, and one end of each microstrip line is grounded via a through-hole to form a high frequency filter. The microstrip lines and the shared through-hole constitute microstrip line resonators, which are coupled via the inductance of the through-hole. With this arrangement, there is no need for an additional coupling element. Thus, the size of the high frequency filter can be reduced. Furthermore, since a large coupling coefficient can be obtained, the high frequency filter can have a broadband characteristic.

High frequency filter, filter device, and electronic apparatus incorporating the same

A method of adjusting characteristics of a dielectric filter including the following steps: forming a dielectric filter having a dielectric body, the dielectric body having an outer surface; forming an external conductor on the outer surface of the dielectric body; and forming at least one hole extending through the dielectric body, the at least one hole having a respective inner surface, and a respective internal conductor and a respective non-conductive portion at the inner surface; the outer surface of the dielectric body comprising first and second end surfaces and a side surface extending between the first and second end surfaces; the at least one hole extending through the dielectric body between the first and second end surfaces; the respective inner conductor being formed as a respective pair of internal conductors conductively connected to the external conductor at respective ends of the at least one hole, the respective non-conductive portion at the inner surface of the at least one hole being spaced from both end surfaces, thereby separating the corresponding pair of internal conductors and defining a respective capacitance between the corresponding pair of internal conductors; and a predetermined portion of the outer surface of the dielectric body being formed with a shape such that a first portion of the external conductor at the predetermined portion of the outer surface is closer to at least one of the internal conductors in the at least one hole as compared with a second portion of the external conductor at a portion of the outer surface of the dielectric body other than the predetermined portion; the method further comprising the steps of: initially forming the respective inner conductor over an entire length of the inner surface of the corresponding hole; and thereafter grinding off a portion of the respective inner conductor with a grinding tool in order to form the non-conductive portion.

Method of adjusting characteristics of dielectric filter

Resonator electrodes are provided on the upper face of a dielectric substrate. The ratios (W /L ) and (W /L ) of the electrode widths W and W to the electrode lengths L and L of the resonator electrodes of the first and last stages are set at substantially 1.05<W/L<1.95. Lead-out electrodes are connected to the resonator electrodes of the first and last stages on the opposite sides of the center axis which is a straight-line axis passing through the center positions of the resonator electrodes of the first and last stages. Thereby, an attenuation pole is generated on the lower band side of the pass-band.

Strip-line filter, duplexer, filter device, communication device, and method of adjusting characteristic of strip-line filter

A method is disclosed which allows the electrical characteristics of a microstrip line filter or the like to be reliably measured using a two-dimensional measuring jig, even if components thereof to be measured are small in size and are not discrete components. A first ground electrode is formed substantially over the entire bottom surface of a dielectric substrate, and resonator electrodes are disposed on the top surface of the dielectric substrate. Input/output electrodes are each connected to a first-stage resonator electrode and a last-stage resonator electrode. Second ground electrodes conductively connected to the first ground electrode are disposed beside each of the input/output electrodes. By this structure, each of the input/output portions is provided with a grounded coplanar guide configuration.

Adjusting method for electrical characteristics of microstrip line filter, duplexer, communication device, and microstrip line type resonator

A conductor line is formed on the upper side of a dielectric plate, and a ground electrode is formed on the underside. Further, electrode non-formation portions are distributed at intervals a in the propagation direction of a signal and at intervals b in the perpendicular direction to the propagation direction. A band-stop or low-pass filter characteristic is produced by increasing the transmission loss in a frequency band determined by the intervals a, and the attenuation in the stop-band is determined by the intervals b in the width direction.

Transmission line, filter, duplexer and communication device

A coplanar resonator comprising first center electrodes each having open ends and a ground electrode which extends along either side thereof is formed on the upper plane of a dielectric substrate, and second center electrodes and a perimeter electrode are formed on the lower plane of the dielectric substrate, so as to face the above center electrodes and ground electrode. A filter, duplexer, and communication device using this resonator are provided, thereby reducing the size of the resonator part formed of electrode patterns on a dielectric substrate, facilitating reduction in size of the overall device, and increasing no-load Q.

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Nagaokakyo, Japan

Tatsuya Tsujiguchi