Murata Manufacturing Co., Ltd.

Murata Mfg. Co., Ltd.

Katsuhito Kuroda

Hideyuki Kato

Jinsei Ishihara

Hideki Tsukamoto

Kengo Onaka

Haruo Matsumoto

Motoharu Hiroshima

Takahiro Okada

Shohachi Nishijima

Hidenori Obiya

Yoshiki Yamada

Reiji Nakajima

Hirofumi Miyamoto

Kazumasa Haruta

Sunao Yamazaki

Yuki Nakaike

A filter device () is formed between an input end (T) and an output end (T), and is configured to attenuate a radio frequency signal in a specific frequency band. The filter device () includes a dielectric substrate () having a multilayer structure, ground electrodes (GNDand GND) formed in the dielectric substrate (), a first coupling line () electrically connected to the input end (T), a second coupling line () electrically connected to the output end (T), and a stub () connected to the first coupling line () and the second coupling line (). The first coupling line () and the second coupling line () are formed in layers different from layers of the ground electrodes (GNDand GND). The first coupling line () and the second coupling line () are disposed in different layers so as to face each other.

Filter device, and antenna module and communication device including the same

An antenna module () includes a dielectric substrate (), antenna groups (A,B) including a plurality of antenna elements (), RFICs (A,B) configured to supply radio-frequency power to the antenna groups (A,B), a divider () configured to divide a radio-frequency signal between the RFICs (A,B), and a ground electrode (GND). The RFICs (A,B) are mounted at a mounting surface () of the dielectric substrate (). The divider () is provided closer to the mounting surface () than to the layer in which the antenna groups (A,B) are provided. The divider () includes a first path having lower impedance and a second path having higher impedance. When viewed in plan view in a normal-line direction with respect to the mounting surface (), a cavity () is formed at a portion of the ground electrode (GND), the portion facing the second path.

Antenna module

The present disclosure includes: an RFIC (A) and an RFIC (B) that are configured to respectively supply radio-frequency power to a first antenna group and a second antenna group; and a divider that divides a reference frequency signal input thereto and outputs the resulting first radio-frequency signals to the RFIC (A) and the RFIC (B). The divider is a Wilkinson-type first divider that is formed of a circuit system of a second impedance that is lower than a first impedance that is an impedance of signal transmission system into which the divider is inserted.

Antenna module and communication device

The present disclosure includes a first circuit that is connected between a power feed port and an antenna port, and a second circuit that is connected between the power feed port and the ground or between the antenna port and the ground. The first circuit is a circuit in which for example a first variable capacitance element is connected in series with a first inductor, and the second circuit is a circuit in which for example a second variable capacitance element is connected in parallel with a second inductor. A switch performs switching at least between a first state in which a second end of the second circuit is connected to a first end of the first circuit and a second state in which the second end of the second circuit is connected to a second end of the first circuit.

Antenna matching circuit, antenna circuit, front-end circuit, and communication apparatus

There are provided an antenna, an antenna tuner configured to adjust frequency characteristics of the antenna, and a control circuit configured to change frequency characteristics of the antenna tuner in a boundary time set for a unit of time of communication. For example, after matching indicators based on VSWRs and received signal strength indicators based on RSSIs have been acquired in a plurality of times of communication space time, the antenna tuner is put into an optimum mode. This suppresses the decrease in communication throughput caused by the adjustment of the antenna tuner and suppresses the interruption of communication at the time of adjustment of the antenna tuner.

Antenna tuner control circuit, front-end circuit and communication device

A variable phase shift circuit has a phase shifter including a first port and a second port; a through path including a first port and a second port; a first switch including a first common port and configured to select the first port of the phase shifter or the first port of the through path and to connect the first port or the first port to the first common port; and a second switch including a second common port and configured to select the second port of the phase shifter or the second port of the through path and to connect the second port or the second port to the second common port. Phase shift amounts between the first common port and the second common port are switched in accordance with selections made by the first switch and the second switch.

Variable phase shifter, variable phase shift circuit, RF front-end circuit, and communication apparatus

Provided is a method for setting a communication channel for a base station employing carrier aggregation, which enables simultaneous use of radio waves at a plurality of frequency bands of different frequencies or a base station apparatus for setting a communication channel in accordance with carrier aggregation, which enables simultaneous transmission and reception at a plurality of frequency bands of different frequencies. At least one of a downlink frequency channel in a first frequency band and a downlink frequency channel in a second frequency band is set such that a frequency range of harmonics of an uplink frequency range in the first frequency band does not overlap a downlink frequency range in the second frequency band, the first frequency band and the second frequency band being included in the plurality of frequency bands for use in carrier aggregation.

Frequency channel setting method and base station apparatus

In an antenna device including a high-band antenna element and a low-band antenna element that are connected to a common feed point and feeding electric power using one feed point, influence by unnecessary resonance of the low-band antenna element in a high band is suppressed. The antenna device includes a high-band antenna element and a low-band antenna element that are connected to a common feed point, an antenna-shortening inductor that is connected to between the low-band antenna element and the feed point, and a capacitor that is connected to the antenna-shortening inductor in parallel.

Antenna device and communication apparatus

A front end circuit includes a circulator having a first port into which a transmission signal is input, a second port into/from which a transmission/reception signal is input/output, and a third port from which a reception signal is output. The impedance of the second port of the circulator is set to a value different from the impedance value of the first port and the third port. With his configuration, the narrowing of a frequency band and the increase in loss, which occur when an impedance matching circuit is additionally provided, are prevented.

Front end circuit and communication apparatus

An elastic wave filter device has a center frequency of a reception frequency band. A plurality of parallel arms are connected to a portion of a series arm on a second signal terminal side of a portion in which a first series-arm resonator is provided. Series-arm resonators among the plurality of series-arm resonators other than the first series-arm resonator include a series-arm resonator having a resonant frequency higher than the resonant frequency of the first series-arm resonator. The resonant frequency of the first series-arm resonator is equal to the reception frequency band.

Elastic wave filter device and communication apparatus equipped with the same

In an acoustic wave filter device, a first filter circuit portion includes a first inductor provided in a series arm that couples an input terminal and an output terminal is serially connected to a first acoustic wave resonator, and a second filter circuit portion includes a second inductor provided in the series arm and second and third acoustic wave resonators and connected between one end and the other end of the second inductor and a ground potential. When the pass band center frequency is set as a first center frequency and the center frequency of a filter defined by the inductance of the first and second inductors and the capacitance of the first to third acoustic wave resonators is set as a second center frequency f, fis less than f

Acoustic wave filter device

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.

Dielectric filter, dielectric duplexer, and communication apparatus

In an acoustic wave filter, first and second filter elements are connected between an unbalanced terminal and first and second balanced terminals on an acoustic wave substrate. The filter elements are longitudinally-coupled surface wave filters including at least three IDTs. One end of the IDTs is mutually connected and is connected to the unbalanced terminal. The other ends of the IDTs are connected by a second connecting line so as to define an unbalanced-side grounded portion. Grounded ends of the IDTs are connected to each other by a first connecting line so as to define a common midpoint grounded portion. The common midpoint grounded portion and the unbalanced-side grounded portion are electrically separated from each other.

Balanced acoustic wave filter and acoustic wave filter

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.

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Matto, Japan

Katsuhito Kuroda