Patents by Inventor Kazunari Kihira

Kazunari Kihira 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).

  • Publication number: 20230246346
    Abstract: An array antenna device includes: a ground plate that is a flat-plate shaped conductor; an element antenna array in which a plurality of tapered slot antennas are linearly arranged on the ground plate along an electric field direction; and a metal plate provided at both ends or one end of an antenna aperture formed in the element antenna array arranged on the ground plate along the electric field direction, the metal plate having a height from the ground plate higher than a height of the tapered slot antenna.
    Type: Application
    Filed: April 10, 2023
    Publication date: August 3, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hikaru Watanabe, Toru Takahashi, Kazunari Kihira, Toru Fukasawa
  • Patent number: 11605903
    Abstract: Waveguide slot array antennas each having slots, that transmit or receive electromagnetic waves and that are formed in a front surface of a waveguide and waveguide slot array antennas each having slots that transmit or receive electromagnetic waves and that are formed in a front surface of a waveguide, and the waveguide slot array antennas and the waveguide slot array antennas are alternately arranged, the waveguide is a ridge waveguide having a ridge formed inside the waveguide, and the waveguide is a ridge waveguide having ridges, formed inside the waveguide.
    Type: Grant
    Filed: August 10, 2016
    Date of Patent: March 14, 2023
    Assignee: Mitsubishi Electric Corporation
    Inventors: Hikaru Watanabe, Takashi Maruyama, Masataka Otsuka, Yu Ushijima, Kazunari Kihira
  • Patent number: 11228104
    Abstract: A calibration device of an array antenna is for a transmission means including a plurality of antenna elements and transmission signal processing systems corresponding to the plurality of antenna elements, in which an antenna element transmission signal is calibrated for amplitude and phase differences and a time difference for each of the antenna elements on the basis of a transmission signal calibrating value, the transmission means being for generating a plurality of transmission radio waves applied with amplitude and phase differences and a time difference corresponding to each of the plurality of antenna elements and emitting the transmission radio waves from the respective antenna elements, the calibration device including: a multicarrier calibration signal generating means for generating a plurality of calibration signals based on, in correspondence, a plurality of subcarriers including a first frequency unit of a subcarrier to which a subcarrier symbol is assigned and a second frequency unit not assig
    Type: Grant
    Filed: July 24, 2018
    Date of Patent: January 18, 2022
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kazunari Kihira, Toru Fukasawa
  • Publication number: 20210344111
    Abstract: A calibration device of an array antenna is for a transmission means including a plurality of antenna elements and transmission signal processing systems corresponding to the plurality of antenna elements, in which an antenna element transmission signal is calibrated for amplitude and phase differences and a time difference for each of the antenna elements on the basis of a transmission signal calibrating value, the transmission means being for generating a plurality of transmission radio waves applied with amplitude and phase differences and a time difference corresponding to each of the plurality of antenna elements and emitting the transmission radio waves from the respective antenna elements, the calibration device including: a multicarrier calibration signal generating means for generating a plurality of calibration signals based on, in correspondence, a plurality of subcarriers including a first frequency unit of a subcarrier to which a subcarrier symbol is assigned and a second frequency unit not assig
    Type: Application
    Filed: July 24, 2018
    Publication date: November 4, 2021
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kazunari KIHIRA, Toru FUKASAWA
  • Patent number: 10992039
    Abstract: An array antenna device, including: a waveguide (1) having a plurality of radiation units (2) arranged on one tube wall thereof, in which the waveguide (1) has a plurality of grooves (3) arranged on an inner side of a tube wall facing the tube wall, movable short-circuit surfaces (4) each electrically short-circuited to an inner wall of one of the grooves (3), and movable short-circuit surface controlling mechanisms (5) for changing positions of the movable short-circuit surfaces (4).
    Type: Grant
    Filed: August 30, 2016
    Date of Patent: April 27, 2021
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kei Yokokawa, Jun Goto, Kazunari Kihira, Tomohiro Takahashi, Masataka Otsuka, Narihiro Nakamoto, Toru Fukasawa, Takuro Sasaki, Tomohiro Mizuno
  • Publication number: 20190260137
    Abstract: Waveguide slot array antennas each having slots, that transmit or receive electromagnetic waves and that are formed in a front surface of a waveguide and waveguide slot array antennas each having slots that transmit or receive electromagnetic waves and that are formed in a front surface of a waveguide, and the waveguide slot array antennas and the waveguide slot array antennas are alternately arranged, the waveguide is a ridge waveguide having a ridge formed inside the waveguide, and the waveguide is a ridge waveguide having ridges, formed inside the waveguide.
    Type: Application
    Filed: August 10, 2016
    Publication date: August 22, 2019
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hikaru WATANABE, Takashi MARUYAMA, Masataka OTSUKA, Yu USHIJIMA, Kazunari KIHIRA
  • Publication number: 20190229418
    Abstract: An array antenna device, including: a waveguide (1) having a plurality of radiation units (2) arranged on one tube wall thereof, in which the waveguide (1) has a plurality of grooves (3) arranged on an inner side of a tube wall facing the tube wall, movable short-circuit surfaces (4) each electrically short-circuited to an inner wall of one of the grooves (3), and movable short-circuit surface controlling mechanisms (5) for changing positions of the movable short-circuit surfaces (4).
    Type: Application
    Filed: August 30, 2016
    Publication date: July 25, 2019
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kei YOKOKAWA, Jun GOTO, Kazunari KIHIRA, Tomohiro TAKAHASHI, Masataka OTSUKA, Narihiro NAKAMOTO, Toru FUKASAWA, Takuro SASAKI, Tomohiro MIZUNO
  • Patent number: 10284239
    Abstract: Disclosed is an antenna device including element antennas for receiving signals, phase control units for controlling the phases of the signals received by the element antennas, a phase value series acquiring unit for acquiring phase value series in which phase values differing among the element antennas and changing with time are provided, a phase value setting unit for setting the phase values to the phase control units in accordance with the phase value series, a combining unit for combining the signals whose phases are controlled into a composite signal, an ADC for digitizing the composite signal, a frequency calculating unit for calculating frequency shift amounts from the phase value series, DDCs for performing frequency conversion on the digitized signal by using the frequency shift amounts, LPFs each for performing low-pass filtering on the signal on which the frequency conversion is performed, and a beam forming unit for forming one or more beam signals by using the signals on each of which the low-pa
    Type: Grant
    Filed: February 6, 2015
    Date of Patent: May 7, 2019
    Assignee: Mitsubishi Electric Corporation
    Inventors: Tasuku Kuriyama, Kazunari Kihira, Masataka Otsuka
  • Patent number: 10142000
    Abstract: A sub-array number determinator is provided to determine a number of sub-arrays to be allocated to each of user terminals detected by a terminal position detector on a basis of relation between positions of the user terminals and a position of an antenna apparatus. An antenna selector selects sub-arrays for the number determined by the sub-array number determinator from among the sub-arrays and allocates the selected sub-arrays for the determined number to each of the user terminals. This structure is capable of preventing interference among beams for user terminals and providing excellent communication quality to the user terminals even in condition where the user terminals are adjacent to each other.
    Type: Grant
    Filed: April 15, 2015
    Date of Patent: November 27, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kazunari Kihira, Makoto Matsuki, Hikaru Watanabe, Hiroki Iura, Masataka Otsuka
  • Publication number: 20180287678
    Abstract: A sub-array number determinator is provided to determine a number of sub-arrays to be allocated to each of user terminals detected by a terminal position detector on a basis of relation between positions of the user terminals and a position of an antenna apparatus. An antenna selector selects sub-arrays for the number determined by the sub-array number determinator from among the sub-arrays and allocates the selected sub-arrays for the determined number to each of the user terminals. This structure is capable of preventing interference among beams for user terminals and providing excellent communication quality to the user terminals even in condition where the user terminals are adjacent to each other.
    Type: Application
    Filed: April 15, 2015
    Publication date: October 4, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kazunari KIHIRA, Makoto MATSUKI, Hikaru WATANABE, Hiroki IURA, Masataka OTSUKA
  • Publication number: 20180269911
    Abstract: Disclosed is an antenna device including element antennas for receiving signals, phase control units for controlling the phases of the signals received by the element antennas, a phase value series acquiring unit for acquiring phase value series in which phase values differing among the element antennas and changing with time are provided, a phase value setting unit for setting the phase values to the phase control units in accordance with the phase value series, a combining unit for combining the signals whose phases are controlled into a composite signal, an ADC for digitizing the composite signal, a frequency calculating unit for calculating frequency shift amounts from the phase value series, DDCs for performing frequency conversion on the digitized signal by using the frequency shift amounts, LPFs each for performing low-pass filtering on the signal on which the frequency conversion is performed, and a beam forming unit for forming one or more beam signals by using the signals on each of which the low-pa
    Type: Application
    Filed: February 6, 2015
    Publication date: September 20, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Tasuku KURIYAMA, Kazunari KIHIRA, Masataka OTSUKA
  • Patent number: 9917377
    Abstract: Disclosed is an antenna device in which an excitation phase changing unit (4) for changing the excitation phases of element antennas (2-1n) to (2-8n) by controlling phase shifters (3-1n) to (3-8n) dependently on preset phase values is disposed, and every time the excitation phases are changed by the excitation phase changing unit (4), a radiation pattern forming unit (12) shifts the phases of a sum signal and a difference signal, and forms a monopulse sum pattern by time-integrating the sum signal after phase shift and also forms a monopulse difference pattern by time-integrating the difference signal after phase shift.
    Type: Grant
    Filed: February 1, 2016
    Date of Patent: March 13, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Makoto Matsuki, Kazunari Kihira, Masataka Otsuka
  • Publication number: 20180019524
    Abstract: Disclosed is an antenna device in which an excitation phase changing unit (4) for changing the excitation phases of element antennas (2-1n) to (2-8n) by controlling phase shifters (3-1n) to (3-8n) dependently on preset phase values is disposed, and every time the excitation phases are changed by the excitation phase changing unit (4), a radiation pattern forming unit (12) shifts the phases of a sum signal and a difference signal, and forms a monopulse sum pattern by time-integrating the sum signal after phase shift and also forms a monopulse difference pattern by time-integrating the difference signal after phase shift.
    Type: Application
    Filed: February 1, 2016
    Publication date: January 18, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Makoto MATSUKI, Kazunari KIHIRA, Masataka OTSUKA
  • Patent number: 8542785
    Abstract: A communication apparatus that can suppress an increase in circuit size and reduce influence of interference, includes reception array antenna elements, a reception digital beam forming (DBF) network that generates a reception beam signal for forming M reception beams using a reception signal, and reception filter banks (FBs) that generate frequency split reception beam signals obtained by frequency-splitting the reception beam signal. The communication apparatus includes an interference-source detecting unit that stores, for each reception beam, an interference candidate beam area estimated based on an initial reception beam characteristic, calculates, based on the frequency split reception beam signals, a reception spectrum, and calculates, based on the reception spectrum and a reception spectrum of a reception beam to the interference candidate beam area, an interference source area.
    Type: Grant
    Filed: July 2, 2009
    Date of Patent: September 24, 2013
    Assignee: Mitsubishi Electric Corporation
    Inventors: Akinori Fujimura, Kazunari Kihira, Yasushi Sogabe
  • Publication number: 20110206155
    Abstract: A communication apparatus that can suppress an increase in circuit size and reduce influence of interference, includes reception array antenna elements, a reception DBF network that generates a reception beam signal for forming M reception beams using a reception signal, and reception FBs that generate frequency split reception beam signals obtained by frequency-splitting the reception beam signal. The communication apparatus includes an interference-source detecting unit that stores, for each reception beam, an interference candidate beam area estimated based on an initial reception beam characteristic, calculates, based on the frequency split reception beam signals, a reception spectrum, and calculates, based on the reception spectrum and a reception spectrum of a reception beam to the interference candidate beam area, an interference source area. The reception DFB network generates a reception beam signal to perform null formation in the direction of the interference source area.
    Type: Application
    Filed: July 2, 2009
    Publication date: August 25, 2011
    Applicant: Mitsubishi Electric Corporation
    Inventors: Akinori Fujimura, Kazunari Kihira, Yasushi Sogabe
  • Publication number: 20100150013
    Abstract: A calibration method according to the present invention includes a step of first channel estimating for transmitting a pilot signal from a first antenna and receiving the pilot signal at a second antenna different from the first antenna to calculate a first channel estimation value; a step of second channel estimating for transmitting a plot signal from the second antenna and receiving the pilot signal at the first antenna to calculate a second channel estimation value; and a step of correction coefficient calculating for calculating, by using the first and second channel estimation values, a correction coefficient.
    Type: Application
    Filed: January 10, 2008
    Publication date: June 17, 2010
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yoshitaka Hara, Akinori Taira, Kenichi Tajima, Kazunari Kihira, Michiaki Takano, Kazuaki Ishioka, Yasunori Nouda
  • Patent number: 6788269
    Abstract: There are disposed four antenna elements which are arranged circumferentially at regular intervals, and four 90-degree hybrids each having four terminals, two 90-degree hybrids which are arranged in parallel are connected in two stages, only one of the output terminals of an upstream 90-degree hybrid and only one of the input terminal of a downstream 90-degree hybrid cross each other and are connected to each other, and the four output terminals of the two downstream 90-degree hybrids and the four antenna elements are connected to each other; the passing phase between the terminals that cross each other within the respective 90-degree hybrids is set to 0 degree, and the passing phase between the terminals that are in parallel within the respective 90-degree hybrids is set to 90 degrees. As a result, the structure of the feed circuit can be simplified, and plural kinds of beams can be formed.
    Type: Grant
    Filed: March 3, 2003
    Date of Patent: September 7, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Isamu Chiba, Kazunari Kihira, Rumiko Yonezawa, Shuji Urasaki
  • Publication number: 20030164804
    Abstract: There are disposed four antenna elements which are arranged circumferentially at regular intervals, and four 90-degree hybrids each having four terminals, two 90-degree hybrids which are arranged in parallel are connected in two stages, only one of the output terminals of an upstream 90-degree hybrid and only one of the input terminal of a downstream 90-degree hybrid cross each other and are connected to each other, and the four output terminals of the two downstream 90-degree hybrids and the four antenna elements are connected to each other; the passing phase between the terminals that cross each other within the respective 90-degree hybrids is set to 0 degree, and the passing phase between the terminals that are in parallel within the respective 90-degree hybrids is set to 90 degrees. As a result, the structure of the feed circuit can be simplified, and plural kinds of beams can be formed.
    Type: Application
    Filed: March 3, 2003
    Publication date: September 4, 2003
    Inventors: Isamu Chiba, Kazunari Kihira, Rumiko Yonezawa, Shuji Urasaki
  • Patent number: 6404387
    Abstract: Since adaptive control has been made by using different reference characters every transmitter-receiver, it has been necessary to provide an adaptive control device every transmitter-receiver. Hereupon, an adaptive array antenna apparatus according to the invention provides a weighting control device for calculating a weight coefficient to control weighting processing so that electric power of array signals synthesized by applying weighting processing to signals received by antennas of a plurality of systems becomes minimum, and an adaptive control device for using the weight coefficient for application of weighting processing to thereby form null points of antenna directivity in a direction, along which interference signals having a greater electric power than that of desired signals arrive, to remove the interference signals and to output array signals to transmitter-receivers.
    Type: Grant
    Filed: July 18, 2001
    Date of Patent: June 11, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kazunari Kihira, Isamu Chiba