Patents by Inventor Yohei Ishikawa

Yohei Ishikawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6255914
    Abstract: A dielectric resonator designed so that there is substantially no loss in a conductor on the surface of a casing forming a shielded cavity, and so that the unloaded Q and the resonant frequency can be changed independently of each other. A cylindrical dielectric block having a pair of electrodes formed respectively on its two opposite surfaces is disposed in a metallic shielded-cavity casing so that one of the electrodes is in contact with an inner bottom surface of the shielded-cavity casing. This electrode is electrically connected to the shielded-cavity casing by soldering or the like. Input/output connectors are coupled to the other electrode on the cylindrical dielectric block.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: July 3, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Seiji Hidaka, Norifumi Matsui, Tomoyuki Ise, Kazuhiko Kubota
  • Patent number: 6246298
    Abstract: A dielectric line switch is provided which is capable of easily controlling the propagation of an electromagnetic wave. Also provided is an antenna device employing said dielectric line switch. As an embodiment of the invention, a plurality of dielectric lines and a plurality of primary radiators are provided on a rotary unit. With the rotation of the rotary unit, the dielectric lines are switched ON and OFF by virtue of mechanical means, so that a desired change-over may be effected among the plurality of primary radiators in a time sharing manner, and the positions of the primary radiators may be shifted within a plane of the focal point of a dielectric lens, thereby enabling the transmission wave beam and/or reception wave beam to scan in a desired manner.
    Type: Grant
    Filed: October 21, 1998
    Date of Patent: June 12, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Koichi Sakamoto, Toru Tanizaki, Hiroshi Nishida, Taiyo Nishiyama, Nobuhiro Kondo, Atsushi Saitoh, Yoshinori Taguchi, Hideaki Yamada
  • Patent number: 6188360
    Abstract: A radio-frequency radiation source comprises electrodes containing opposing electrodeless parts formed on both sides of a dielectric plate in which the electrodeless parts are made to function as a dielectric resonator, a slit formed in the electrodeless part, and a switching element mounted over the slit. Further, a transmission line coupled to the dielectric resonator is provided. As constructed this way, the resonance frequency of the resonator is switched by turn-on and turn-off of the switching element. When the resonator resonates with the frequency of a signal propagated through the transmission line, the energy of the electromagnetic field is radiated to the outside through a slot.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: February 13, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takatoshi Kato, Koichi Sakamoto, Kenichi Iio, Yohei Ishikawa
  • Patent number: 6184758
    Abstract: Proposed are a resonator which can easily establish coupling with input/output means, an external circuit, etc., and a filter, duplexer and communication apparatus each having a wide-band frequency characteristic. Electrodes having polygonal openings defined therein are formed in both principal planes of a dielectric substrate such that the openings are positioned to face each other. The dielectric substrate is arranged with the aid of spacers between a metal-made upper conductor case and a lower conductor case having a shield conductor formed therein, the upper and lower conductor cases being positioned to face each other with gaps left relative to the dielectric substrate. Portions of the dielectric substrate between pairs of the openings facing to each other serve as resonance areas and are coupled respectively with input/output electrodes.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: February 6, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Toshiro Hiratsuka, Tomiya Sonoda, Shigeyuki Mikami, Yutaka Ida, Kiyoshi Kanagawa
  • Patent number: 6175335
    Abstract: A dielectric lens antenna having a lens comprising a dielectric material and a heating body disposed on a surface of the lens. The dielectric lens antenna has a snow-melting function, which prevents degradation in lens-efficiency.
    Type: Grant
    Filed: June 29, 1999
    Date of Patent: January 16, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Koichi Sakamoto, Hideaki Yamada, Fuminori Nakamura
  • Patent number: 6169301
    Abstract: A planar dielectric integrated circuit is provided such that energy conversion loss between a planar dielectric line and electronic components is small and that impedance matching between them can be easily obtained. By providing slots which oppose both main surfaces of a circuit substrate, two planar dielectric lines are constructed. A slot line, and a first line-conversion conductor pattern which is connected to the electromagnetic field of the slot line and a first planar dielectric line in order to perform line conversion, are provided at the end portion of the first planar dielectric line, including a slot. A coplanar line and a second line-conversion conductor which is made to project in a direction at right angles to a second planar dielectric line is provided at the end portion of the second planar dielectric line, including a slot. A semiconductor device is placed in such a manner as to be extended over the coplanar line and the slot line.
    Type: Grant
    Filed: February 26, 1998
    Date of Patent: January 2, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Koichi Sakamoto, Sadao Yamashita, Takehisa Kajikawa
  • Patent number: 6166614
    Abstract: A nonradiative planar dielectric line exhibits low transmission losses and is easily connectable to electronic components. A first slot is provided between two electrodes on a first main surface of a dielectric plate. A second slot is provided between two electrodes on a second main surface of the dielectric plate. A first conductor is electrically connected to the electrodes on the first main surface and also covers the first slot. A second conductor is electrically connected to the electrodes on the second main surface and also covers the second slot. An integrated circuit using the above type of dielectric line is also provided. Thus, apparatuses using the above dielectric lines or integrated circuits are miniaturized.
    Type: Grant
    Filed: June 5, 1998
    Date of Patent: December 26, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Koichi Sakamoto, Atsushi Saitoh, Kenichi Iio
  • Patent number: 6144268
    Abstract: The invention provides a high-frequency transmission line and a dielectric resonator having a small size and having an effectively reduced loss. When a transmission line is produced, an electrode is formed on a dielectric plate in such a manner that one or more gaps are formed in an edge portion of the electrode along an edge of the electrode thereby forming thin line-shaped electrodes whereby a current which would otherwise be concentrated to a great extent in the edge portion of the electrode is divided into a plurality of portions.
    Type: Grant
    Filed: October 9, 1998
    Date of Patent: November 7, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Norifumi Matsui, Seiji Hidaka, Yohei Ishikawa
  • Patent number: 6104264
    Abstract: A dielectric waveguide has a plurality of dielectric ceramic sheets each having a high-dielectric-constant portion and a low-dielectric-constant portion. The dielectric ceramic sheets are laminated and baked and electrode films are formed on the outer surfaces thereof. Thus, a dielectric waveguide is obtained in which the high-dielectric-constant portion serves as a propagating area and the low-dielectric-constant portion serves as a non-propagating area.
    Type: Grant
    Filed: February 5, 1998
    Date of Patent: August 15, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Toru Tanizaki, Hiroshi Nishida, Atsushi Saitoh
  • Patent number: 6100554
    Abstract: An intrinsic device section is provided by laminating a drain area, an intermediate area, and a source area above a GaAs substrate and by forming a channel area at one oblique surface thereof. A drain electrode ohmic connected to the drain area extends toward the output side, a source electrode ohmic connected to the source area extends above the drain electrode with a dielectric layer placed therebetween, and thereby an output micro-wave transmission line is formed. A gate electrode Schottky connected to the channel area extends toward the input side, the source electrode extends above the drain electrode with the dielectric layer placed therebetween, and thereby an input micro-wave transmission line formed.
    Type: Grant
    Filed: June 20, 1997
    Date of Patent: August 8, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Koichi Sakamoto
  • Patent number: 6087912
    Abstract: An electronic module, comprising: a dielectric base plate having first and second opposing surfaces on which respective electrodes are disposed such that respective areas at the first and second surfaces are free of electrode material and aligned relative to one another to form a dielectric resonator; a first electronic component coupled to the base plate; and a first circuit sheet having first and second opposing surfaces, at least one aperture between the surfaces, and a conductor pattern disposed on the first surface, the first circuit sheet being disposed on the base plate such that: (i) the first electronic component is at least partially received within the aperture; and (ii) at least part of the conductor pattern is coupled to the dielectric resonator.
    Type: Grant
    Filed: April 14, 1998
    Date of Patent: July 11, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Koichi Sakamoto, Kenichi Iio, Sadao Yamashita, Yohei Ishikawa
  • Patent number: 6069543
    Abstract: A dielectric resonator capable of adjusting a resonance frequency, reducing occurrence of a mode jump if it is applied to an oscillator and being manufactured at a low cost. The dielectric resonator has a pair of upper and lower opposing conductive plates; a dielectric substrate disposed between the conductive plates; a first electrode formed on one surface of the dielectric substrate, the first electrode having a first opening; a second electrode formed on another surface of the dielectric substrate, the second electrode having a second opening corresponding to the first opening so that a resonator is formed by a portion of the dielectric substrate disposed between the first and second openings; and a variable capacitor located in a portion of the dielectric substrate in which an applied electromagnetic field is confined in and around the resonator.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: May 30, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Toshiro Hiratsuka, Sadao Yamashita, Kenichi Iio
  • Patent number: 6066598
    Abstract: A superconductor layer is formed on one side of a dielectric substrate, and with this superconductor layer as a conductor layer of the bottommost layer, superconductor layers and dielectric layers are alternately laminated with each other. Thus, a superconducting multilayer electrode is provided which is laminated with at least one TEM mode transmission line which is constituted of a pair of superconductor layers with a dielectric layer sandwiched in between, and the superconductor layer and the dielectric layer have film thicknesses which are set so that the maximum value of the current density flowing through each superconductor layer becomes the same. The resistance to electric power of the superconducting multilayer electrode is proportional to the number of laminated layers.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: May 23, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Seiji Hidaka, Norihumi Matsui, Tomoyuki Ise
  • Patent number: 6052087
    Abstract: The invention provides an antenna in which a signal is directly transferred from a planar dielectric transmission line to a primary radiator without having to perform transmission mode conversion from the planar dielectric transmission mode to another mode such as a coplanar transmission mode, a microstrip transmission mode, or a waveguide transmission mode thereby eliminating the transmission loss which would otherwise occur due to the transmission mode conversion. A dielectric resonator is disposed in the vicinity of the end of the planar dielectric transmission line PDTL formed between two slots disposed on both sides of a dielectric plate. Furthermore, a slotted plate, a lens supporting base, and a dielectric lens are disposed one on another.
    Type: Grant
    Filed: April 8, 1998
    Date of Patent: April 18, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Koichi Sakamoto, Kenichi Iio, Hideaki Yamada
  • Patent number: 6052041
    Abstract: A dielectric resonator designed so that there is substantially no loss in a conductor on the surface of a casing forming a shielded cavity, and so that the unloaded Q and the resonant frequency can be changed independently of each other. A cylindrical dielectric block having a pair of electrodes formed respectively on its two opposite surfaces is disposed in a metallic shielded-cavity casing so that one of the electrodes is in contact with an inner bottom surface of the shielded-cavity casing. This electrode is electrically connected to the shielded-cavity casing by soldering or the like. Input/output connectors are coupled to the other electrode on the cylindrical dielectric block.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: April 18, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Seiji Hidaka, Norifumi Matsui, Tomoyuki Ise, Kazuhiko Kubota
  • Patent number: 6011983
    Abstract: An NRD waveguide band-pass filter apparatus is provided which is simple in construction, which can be easily manufactured as well as being small in size and light in weight, and which operates in a single operating mode. The NRD waveguide band-pass filter apparatus includes a plurality of NRD waveguide resonators arrayed in such a way that each two adjacent NRD waveguide resonators are electromagnetically coupled to each other. A plurality of arrayed rectangular dielectric waveguides are interposed between an upper surface portion and a lower surface portion of a rectangular dielectric housing, which are parallel to each other. The upper surface portion and the lower surface portion and the plurality of arrayed rectangular dielectric waveguides are formed integrally, thus forming the housing. A first superconducting electrode and a second superconducting electrode are formed on the outer surfaces of the upper surface portion and the lower surface portion, respectively.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: January 4, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Seiji Hidaka, Norifumi Matsui
  • Patent number: 6008755
    Abstract: An antenna-shared distributor is provided such that a non-conductor section is provided in a part of two conductor planes, a dielectric resonator which resonates in the HE111 mode is disposed between the conductor planes, and first and second dielectric strips whose respective end portions face the dielectric resonator are disposed, forming first and second dielectric lines and further, a voltage-controlled oscillator and a mixer are connected to the first and second dielectric lines, respectively.
    Type: Grant
    Filed: October 22, 1997
    Date of Patent: December 28, 1999
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Toru Tanizaki, Hiroshi Nishida, Atsushi Saitoh
  • Patent number: 5986527
    Abstract: A small and inexpensive planar dielectric line that can be easily connected to electronic parts, such as ICs, and has smaller conduction losses. The planar dielectric line includes a dielectric substrate having first and second surfaces opposedly facing each other. A first slot having a predetermined width is interposed between first and second electrodes on the first surface of the dielectric substrate. A second slot having the same width as the first slot is disposed between third and fourth electrodes on the second surface of the dielectric substrate. The first and second slots opposedly face each other. The permittivity and the thickness of the dielectric substrate are determined so that a planar electromagnetic wave can propagate in a propagation region of the substrate interposed between the first and second slots while being substantially totally reflected on the first surface of the substrate adjacent to the first slot and the second surface of the substrate near the second slot.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: November 16, 1999
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Toshiro Hiratsuka, Sadao Yamashita, Kenichi Iio
  • Patent number: 5982032
    Abstract: An electronic device includes one or more GaAs integrated circuits having a plurality of mutually independent field-effect transistors formed on a GaAs base-member; and one or more high-dielectric-constant base-members including a passive element on a surface thereof or therein.
    Type: Grant
    Filed: August 1, 1997
    Date of Patent: November 9, 1999
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Koichi Sakamoto, Hiroaki Tanaka
  • Patent number: 5973580
    Abstract: A nonradiative planar dielectric line exhibits low transmission losses and is easily connectable to electronic components. A first slot is provided between two electrodes on a first main surface of a dielectric plate. A second slot is provided between two electrodes on a second main surface of the dielectric plate. A first conductor is electrically connected to the electrodes on the first main surface and also covers the first slot. A second conductor is electrically connected to the electrodes on the second main surface and also covers the second slot. An integrated circuit using the above type of dielectric line is also provided. Thus, apparatuses using the above dielectric lines or integrated circuits are miniaturized.
    Type: Grant
    Filed: June 5, 1998
    Date of Patent: October 26, 1999
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yohei Ishikawa, Koichi Sakamoto, Atsushi Saitoh, Kenichi Iio