Murata Manufacturing Co., Ltd.

Murata Mfg. Co., Ltd.

Murana Mfg. Co. Ltd.

Harufumi Mandai

Teruhisa Tsuru

Kenji Asakura

Seiji Kanba

Koji Shiroki

Yoshikazu Chigodo

Tsuyoshi Suesada

Ken Tonegawa

Toshifumi Oida

Noboru Kato

Yasuyuki Naito

Michihiro Murata

Norio Nakajima

Tomoya Bando

Yukio Sakabe

Hisatake Okamura

Mitsuhide Kato

Kunisaburo Tomono

Atsushi Tojyo

Yoshihiro Yoshimoto

Atsushi Tojo

Norio Sakai

Yukio Sakamoto

Yasunobu Yoneda

Naoki Mizoguchi

Isao Kato

Tadashi Morimoto

Atsushi Kumano

Yukio Banba

Kimihide Sugo

Seiji Kanaba

Jun Sasaki

Satoshi Ishino

Hiroji Tani

Hiroshi Takagi

Koji Furutani

Toshimi Kaneko

Takuji Nakagawa

Kikuo Wakino

Takahiro Watanabe

Takeshi Tanabe

Atsushi Inoue

Yukio Tanaka

Kazuhiro Iida

Toshio Kawabata

Kunihiro Watanabe

Sadayuki Matsumura

Akihiro Ochii

Yoshiaki Mori

Tomonori Ito

Yasuo Fujiki

Hiroaki Ichikawa

Yujiro Dakeya

Kanehito Honma

Kunitaro Nishimura

Kiyoshi Iwai

Norihiro Shimada

Masayuki Yamada

Hiromichi Sakai

Yo Funada

Hiroaki Tsumori

Keiji Asakawa

Nori Nakajima

Yoichiro Suga

Hidemichi Mori

Toyoaki Tsunematsu

Shinichi Takakura

Shinichi Okubo

Shinichi Ohkubo

Mitsuhide Katou

There is disclosed a method of producing a ceramic multilayer substrate by laminating a plurality of glass-ceramic green sheets made of a glass-ceramic containing an organic binder and a plasticizer to form a laminate; and firing the laminate; further comprising: applying to or overlaying on the surfaces of the glass-ceramic green sheets inorganic compositions, the sintering temperature of the inorganic compositions being higher than that of the glass-ceramic green sheets; laminating a plurality of the glass-ceramic green sheets having the inorganic compositions applied to or overlaid on the surfaces of the glass-ceramic green sheets respectively, to form a part of the laminate; and laminating a plurality of the glass-ceramic green sheets to form the other part of the laminate.

Method of producing ceramic multilayer substrate

A compact frequency multiplier can perform high-degree frequency multiplication and can be incorporated in a wireless device. The frequency multiplier includes an input terminal for inputting an input signal, a first resonant circuit resonating with the frequency &ohgr; of the input signal, a second resonant circuit and an idler circuit, which resonate with the frequency n&middot;&ohgr; that is, n times the frequency of the input signal, a variable reactor such as a varactor diode, coupling-adjusting capacitors, a bias resistor, and an output terminal for outputting multiplied output signals. In one embodiment, the frequency multiplier is a current-excitation type. The first resonant circuit and the second resonant circuit, each of which is constituted of an LC series resonant circuit, are connected in series between the input terminal and the output terminal. In addition, a parallel circuit constituted of the idler circuit and the varactor diode is connected to a connection point between the first and second resonant circuits and the input terminal and the output terminal.

Frequency multiplier and wireless device incorporating same

A band-pass filter includes a metal film provided on a dielectric body. The shape and size of the metal film and the coupling points of input-output coupling circuits are selected such that first and second resonance modes are generated. The metal film has protruding portions or concavities provided thereon such that resonance electric field strength in the first or second resonance mode is controlled to couple the first and second resonance modes to each other.

Band-pass filter

A dual mode band pass filter is constructed to be very compact and such that the coupling strength and bandwidth can be easily and widely adjusted while maintaining sufficient freedom of design. A metal film for forming a resonator is arranged on a first main surface of a dielectric body or at a certain height in the dielectric body. At least one ground electrode is arranged such that the ground electrode is opposed to the metal film via the dielectric body. The metal film is connected to input/output coupling circuits. In the region where the metal film is opposed to the ground electrode, two portions are partially provided. Each of these two portions has a relative permittivity that is different from the relative permittivity of the remaining portion, in order to couple two resonance modes.

Dual mode band pass filter

A duplexer includes a branch circuit connected to an antenna and arranged to branch to a receiving side and a transmitting side, a receiving-side LC parallel resonant-type filter connected to the receiving-side of the branch circuit and arranged to cause a reception signal to be passed and a transmission signal to be attenuated, a surface acoustic wave filter connected to the receiving-side LC parallel resonant-type filter defining a subsequent stage of the receiving-side LC parallel resonant-type filter and arranged to cause the reception signal to be passed and the neighborhood of the high-frequency side of the reception signal to be attenuated, and a transmitting-side LC parallel resonant-type filter connected to the transmitting-side of the branch circuit and arranged to cause the transmission signal to be passed and the reception signal to be attenuated.

Duplexer and mobile communication device using the same

A portable telephone includes a portable telephone body made from plastic having a receiver, a transmitter, and dial keys, and a chip antenna which is mounted on a circuit board secured at the inside of the portable telephone body and which is electrically connected to an RF section provided on the circuit board in the portable telephone. The chip antenna is disposed near the transmitter at a location where a transmitted electromagnetic signal is unlikely to be affected by the body of a person who is holding the portable telephone.

Mobile communication apparatus

A high-frequency filter serving as a bandpass filter has three transmission lines SL to SL side-coupled in three stages. The transmission lines SL to SL are respectively connected in parallel to capacitors C to C . One end of the input transmission line SL is connected to an input terminal Pi through an input capacitor C . One end of the output transmission line SL is connected to an output terminal Po through an output capacitor C . The other ends of the transmission lines SL and SL are connected and the connection point is connected to the ground through an inductor Lg for forming a pole. One end of the transmission line SL is connected to the ground.

High-frequency filter, complex electronic component using the same, and portable radio apparatus using the same

The invention provides a complex electronic component, comprising; a multilayer substrate formed by laminating a plurality of dielectric layers; a first concave part being provided at least at the bottom surface of said multilayer substrate; a filter comprising at least one first passive element disposed within said multilayer substrate; an external terminal provided on at least one of the flat portion of the bottom surface and the side face of said multilayer substrate; either one of an active element or a second passive element mounted on the top surface of said multilayer substrate, a surface acoustic wave element mounted inside of said first concave portion of said multilayer substrate; and a flat cap provided at the opening of said first concave portion of said multilayer substrate so as to cover said opening said first concave portion. The size of the above complex electronic component is compact.

Complex electronic component with a first multilayer filter having a cavity in which a second filter is mounted

A portable terminal device including a main body including a data entry keyboard; a cover openably and closably attached to the main body and establishing a connecting portion between the main body and the cover; a display disposed on the inner side of the cover; a chip antenna disposed on the cover at a place other than the display and opposed to the connecting portion; the chip antenna including a ceramic base body, a conductor disposed at least either inside the base body or on a surface thereof, and a feeding terminal disposed on a surface of the base body and connected to one end of the conductor. The above portable terminal device has the directivity of an antenna in a desired direction without increasing the size and weight of the portable terminal device and without having a bulky and/or separate and/or protruding antenna device.

Portable terminal device with chip antenna

An antenna includes a spirally wound conductor composed of a copper wire or a covered copper wire, and a covering material consisting essentially of a resin or a resin mixture with 1<&egr;&lE;10. At least part of the conductor is covered with the covering material. One end of the conductor leads to the outside of the covering material to form an external terminal. Another end of the conductor forms a free end in the covering material. In addition, a method for adjusting the resonant frequency of the antenna includes at least the step of changing a winding interval of a part of the conductor which is not covered with the covering material or the step of covering with the covering material a part of the conductor which is not covered with the covering material, or both. Furthermore, the antenna preferably satisfies the following numerical expression: 1.3&lE;l/a&middot;n &lE;4 where l represents the coil length of said conductor; a represents the diameter of said conductor; and n represents the number of turns of said conductor.

Antenna and resonant-frequency-adjustment method therefor

An antenna apparatus,includes a chip antenna,provided with a conductor,, a power-supply electrode,to which one end of the conductor,is connected, and a terminal electrode,to which the other end of the conductor is connected; and a mounting substrate,provided with a line-shaped radiative conductor,formed by printing an electrically conductive material on a surface, a line-shaped conductive pattern,, and a substantially rectangular ground electrode,. The chip antenna,is mounted on the mounting substrate,. The power-supply electrode,of the chip antenna,is connected through the conductive pattern,on the mounting substrate,to a power-supply source V. The terminal electrode,of the chip antenna,is connected to one end of the radiative conductor,on the mounting substrate

Antenna apparatus and mobile communication apparatus using the same

Complex electronic component

An antenna device, comprising an antenna unit including basic body comprising at least one of dielectric ceramic and magnetic ceramic, at least one conductor disposed at least one of inside and on a surface of the basic body, and a feeding electrode for applying a voltage to the conductor disposed on the surface of the basic body; a mounting board on which the antenna unit is mounted; a ground part in association with the mounting board and adapted to resonate with the antenna unit; and a length in the polarization direction of a radio wave of the ground part being about &lgr;/4 or more, where &lgr; is a wavelength of the radio wave, the basic body comprising a first generally planar sheet having a plurality of spaced, first conductors formed on one major surface thereof and a second generally planar sheet having a plurality of spaced second conductors formed on one major surface thereof; the first and second generally planar sheets being laminated together to form an elongated structure wherein respective pairs of the first and second conductors are coupled to one another to form respective spiral loops of a spiral antenna so that a central axis of the spiral antenna extends generally parallel to a longitudinal direction of the elongated structure; each of the sheets being formed of a material having a permeability of 1<&mgr;<7 or a dielectric constant &egr; of 1<&egr;<130; and a feeding terminal coupled to one end of the spiral antenna so that the antenna unit forms a mono-pole antenna, the antenna unit and the ground part together functioning as a dipole antenna.

Antenna device

Growing community of inventors

Takatsuki, Japan

Harufumi Mandai