Murata Manufacturing Co., Ltd.

Shoji Nagumo

Kazunari Kawahata

Takashi Ishihara

Kengo Onaka

Nobuhito Tsubaki

Jin Sato

Kanta Motoki

Akira Miyata

Masashi Nakazato

Tomohiro Nagai

Atsuyuki Yuasa

Yuji Shintomi

Motoyasu Nakao

Ken Okada

Minoru Iwanaga

Noriyuki Ueki

Tetsuro Harada

Hirotaka Fujii

Hiromasa Koyama

Junichi Kurita

Kunihiro Miyahara

Masaaki Takata

Yutaka Masuda

Mie Shimizu

Keiji Hiejima

Masahi Nakazato

Yujie Dai

Shiyunsuke Ootomo

Xiaoxing Zhang

Yingjie Lu

Kazuyuki Furuya

Yusaku Muroya

A front-end module includes: a first front-end circuit that transmits signals in a first band in a CA mode; and a second front-end circuit that transmits signals in a second band in the CA mode. The second front-end circuit includes a second quadplexer for the first and second bands. The first front-end circuit includes: a first quadplexer for the first and second bands; and an impedance variable circuit that is connected to a transmission terminal that is included in the first quadplexer and corresponds to the second band. In the CA mode, the impedance variable circuit serves as a reflection circuit that causes reflection of transmission waves in the second band. In a non-CA mode, the impedance variable circuit serves as a matching circuit that transmits or absorbs transmission waves in the second band.

Front-end module and communication device

An electronic component includes a multilayer body including dielectric layers, a circuit pattern, and band-shaped conductor patterns. The circuit pattern includes a conductor pattern that is disposed inside the multilayer body and defines an inductor. The band-shaped conductor patterns are grounded and cover a portion of a shield surface. An internal surface is located between the circuit pattern and an upper surface. On a shield surface, a non-shielded area is provided which is not covered with any of the band-shaped conductor patterns, and through which magnetic flux generated from the inductor is able to pass.

Electronic component

A high-frequency front-end circuit includes a diplexer, a duplexer, and a low-band-side multiple reflection prevention unit. The diplexer includes an antenna connection terminal, a low-band-side terminal, and a high-band-side terminal, and separates a low-band communication signal and a high-band communication signal. The duplexer separates a transmission signal and a reception signal of the low-band communication signal. The multiple reflection prevention unit is disposed between the low-band-side terminal and the duplexer and reduces or prevents multiple reflections of a leakage signal of the high-band communication signal which leaks to the low band side.

High-frequency front-end circuit

A front-end module that uses a carrier aggregation scheme in which Band, which is selected from a low-frequency band group, and Band, which is selected from a high-frequency band group, are used simultaneously for communication includes a plurality of signal paths that connect a power amplifier module to an antenna element, and an antenna switch module that switches connection between the antenna element and the plurality of signal paths. Harmonics of Band have frequencies that are included in Band. The front-end module further includes a switch element disposed in a TDD transmission path.

Front-end module

This disclosure provides an antenna apparatus in which stable antenna characteristics are maintained by detecting surrounding conditions that affect the antenna characteristics and appropriately compensating the antenna characteristics. More specifically, when surrounding condition such as a human body (e.g., a palm or fingers) approaches and enters an electric field of a pseudo dipole formed by an antenna element electrode, a stray capacitance is sensed and stable antenna characteristics are maintained by appropriately controlling an antenna matching circuit to compensate for a change in the antenna characteristics due to the approach of the surrounding condition.

Antenna apparatus

A stray capacitance is generated between an antenna element and a ground electrode. A capacitance detection circuit detects the stray capacitance. An antenna matching circuit, is provided along a wireless communication signal path, which is a transmission path between the antenna element and a feeder circuit. A feedback control circuit transmits a control signal to the variable matching circuit on the basis of a detection result of the capacitance detection circuit in accordance with the stray capacitance. The capacitance detection circuit includes a constant current source and a timing circuit to measure the time taken to charge the antenna from the constant current source and for the voltage to reach a predetermined voltage.

Antenna device

A high frequency circuit module includes a variable inductance circuit portion and a reactance circuit portion. The variable inductance circuit portion is connected between an antenna port and ground. The variable reactance circuit is connected between the antenna port and a front-end port. The variable inductance circuit portion includes a first inductor, a second inductor, and a switch. The first inductor is connected between the antenna port and the ground. The second inductor and the switch are connected in series, and this series circuit is connected in parallel to the first inductor.

High frequency circuit module

A low-frequency radiating element and a high-frequency radiating element are configured so as to respectively operate in a relatively low frequency band and a relatively high frequency band that are non-contiguous with each other. A matching circuit is inserted between a transmission/reception circuit and a branching point. A high-frequency variable reactance circuit is inserted between the branching point and the high-frequency radiating element. A low-frequency variable reactance circuit is inserted between the branching point and the low-frequency radiating element. The high-frequency variable reactance circuit and the low-frequency variable reactance circuit are configured such that their reactances can be adjusted independently of each other.

Antenna device and matching circuit module for antenna device

A capacitance detecting circuit includes a constant current source supplying a constant current to a voltage detection point, a time measuring unit measuring time of charge until the voltage of the voltage detection point reaches a prescribed voltage, a storage unit and an operation unit. The storage unit stores first data obtained in advance concerning the time of charge of a capacitance element having a known capacitance value, and second data obtained in advance concerning the time of charge of a capacitance component. The operation unit generates third data representing the time of charge of an object of detection from a difference between the first measurement value of the time measuring unit when the capacitance component is connected to the voltage detection point and the second data, and based on the ratio between the third data and the first data and the known capacitance value, calculates the capacitance value of the object of detection.

Module and capacitance detecting method

In an antenna structure in which a base is mounted in a ground region on a circuit board, the base having formed thereon a driven radiating electrode and a parasitic radiating electrode, the parasitic radiating electrode causing multiple resonance at least in a harmonic resonant frequency band of the driven radiating electrode, capacitance loading means for loading a capacitance to a harmonic-mode zero voltage region of the driven radiating electrode is provided. The capacitance loading means is electrically connected to a ground electrode in the ground region on the circuit board via a grounding conduction path and switching means. By switching the switching means ON/OFF, capacitance loading by the capacitance loading means to the harmonic-mode zero voltage region of the driven radiating electrode is switched ON/OFF to switch a base resonant frequency in a base resonant frequency band of the driven radiating electrode.

Antenna structure and wireless communication apparatus including same

In an antenna structurein which a feed radiation electrode provided on a dielectric base member performs an antenna operation in a fundamental mode and an antenna operation in a higher-order mode with a resonant frequency higher than that in the fundamental mode, one end of the feed radiation electrode defines a feed end connected to a circuit for radio communication, and the other end of the feed radiation electrode defines an open end. The position of a capacitance-loading portion &#x3b1; is set in advance between the feed end and the open end of the feed radiation electrode. A capacitance-loading conductor is connected to one or both of the feed end and the capacitance-loading portion &#x3b1; of the feed radiation electrode. The capacitance-loading conductor forms a capacitance for adjusting a resonant frequency in the fundamental mode between the feed end and the capacitance-loading portion &#x3b1;.

Antenna structure and radio communication apparatus including the same

A feed radiation electrode including two branched radiation electrodes is provided on the surface of a substrate. Non-feed radiation electrodes are provided on both sides of the feed radiation electrode and near the branched radiation electrodes. The branched radiation electrode and the non-feed radiation electrode are double-resonated in the same frequency band. The branched radiation electrode and the non-feed radiation electrode are double-resonated in the same frequency band which is higher than that of the branched radiation electrode and the non-feed radiation electrode.

Antenna device and radio communication equipment including the same

In a multi-resonance antenna, at an open end of a radiation electrode of a feeding element and an open end of a radiation electrode of a parasitic element capacitance loading electrodes and ground electrodes are arranged opposite to each other. In the opposing portions, electric-field deflectors are provided, thus reducing the electric-field coupling between the feeding element and the parasitic element.

Multi-resonance antenna

A surface mount type antenna includes a loop-shaped fed radiation electrode provided on a substrate, and a non-fed radiation electrode is arranged close to the fed radiation electrode with a gap provided therebetween. One end side of the non-fed radiation electrode is grounded, and the other end side is an open end. A signal is sent to the non-fed radiation electrode from the fed radiation electrode by electromagnetic coupling to perform a resonant operation. The fed radiation electrode and the non-fed radiation electrode generate a double-resonant state. The double resonance extends the frequency band. When the fed radiation electrode and the non-fed radiation electrode are provided on the substrate to define an antenna, the size of the antenna is greatly reduced.

Growing community of inventors

Kawasaki, Japan

Shoji Nagumo