Patents by Inventor Takashi Yamagajo

Takashi Yamagajo 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: 11296400
    Abstract: An antenna device includes a ground plane that includes an edge and a surface, a protruding metallic member that includes a first connecting part and a second connecting part coupled to the ground plane, protrudes from the edge, and constructs a first loop including the edge, and a T-shaped antenna element that extends from a feeding point to a first end and a second end along the edge, the feeding point being disposed in the vicinity of the surface between the first connecting part and the second connecting part of the first loop, wherein a length of the first loop corresponds to an electric length of one wavelength in a first frequency, and corresponds to an electric length of two wavelengths in a second frequency that is a second order harmonic of the first frequency.
    Type: Grant
    Filed: April 3, 2019
    Date of Patent: April 5, 2022
    Assignee: FUJITSU LIMITED
    Inventors: Takashi Yamagajo, Yohei Koga, Manabu Yoshikawa, Tabito Tonooka, Hirotake Sumi
  • Publication number: 20210273332
    Abstract: An electromagnetic wave control device that controls a directionality of radio waves emitted by an antenna, the electromagnetic wave control device includes: a reflector arranged on a side opposite to an emission side of the radio waves of the antenna; and a conductor plate that is arranged on the emission side of the radio waves of the antenna and on which a conductor is formed, wherein in the conductor plate, a plurality of holes formed by opening the conductor is provided in a grid pattern, and has an inner edge length with which the hole positioned at the center resonates in correspondence with one wavelength of a communication wavelength, and the inner edge length of the hole is formed to be longer as going outward from the center.
    Type: Application
    Filed: May 18, 2021
    Publication date: September 2, 2021
    Applicant: FUJITSU LIMITED
    Inventors: Yohei Koga, Yasumitsu BAN, Takashi YAMAGAJO, Manabu Yoshikawa, HARUHIKO HORIZOE
  • Patent number: 11024946
    Abstract: An antenna device includes: a ground plane which has an edge side; a metal member arranged along the edge side of the ground plane; a first connection line which couples the metal member and the ground plane; a second connection line which couples the metal member and the ground plane; and a power feeding element which has a power feeding point, extends along the metal member from the power feeding point between the first connection line and the second connection line, and is electromagnetic-field-coupled to the metal member.
    Type: Grant
    Filed: February 26, 2019
    Date of Patent: June 1, 2021
    Assignee: FUJITSU LIMITED
    Inventors: Yohei Koga, Takashi Yamagajo, Manabu Kai, Tabito Tonooka
  • Patent number: 10862212
    Abstract: An antenna device includes a ground plane having an edge side, a monopole antenna element that communicates in a first frequency, and that has a first feeding point, a first line that extends from the first feeding point in a direction away from the edge side of the ground plane, and a second line that is coupled to the first line and extends along the edge side, a plurality of dipole feeding elements that communicate at a second frequency higher than the first frequency, and are disposed, with respect to the ground plane, in positions that match the positions of the second line with respect to the ground plane, and a plurality of reflectors that reflect electromagnetic waves radiated by the plurality of feeding elements, and are disposed respectively in correspondence to the plurality of feeding elements between the ground plane and the plurality of feeding elements.
    Type: Grant
    Filed: December 20, 2018
    Date of Patent: December 8, 2020
    Assignee: FUJITSU LIMITED
    Inventors: Takashi Yamagajo, Manabu Kai, Yohei Koga, Tabito Tonooka, Hirotake Sumi
  • Patent number: 10790587
    Abstract: A multiband antenna includes a ground conductor, a first conductor disposed at a predetermined distance from the ground conductor, formed linearly, and configured to have a length to resonate at first and second frequencies, the first conductor including a power feeding point, a second conductor coupled to the first conductor at both ends of the second conductor, disposed closer to a side of the ground conductor than the first conductor, formed linearly, and configured to form a slit between the first and second conductors and resonate together with the first conductor at a third frequency, and a third conductor provided at one or more ends of the first conductor and configured to extend from a first end of the one or more ends to the side of the ground conductor to be electromagnetically coupled to the ground conductor at the third frequency, wherein the conductors has conductivity.
    Type: Grant
    Filed: March 18, 2019
    Date of Patent: September 29, 2020
    Assignee: FUJITSU LIMITED
    Inventors: Yohei Koga, Manabu Kai, Masatomo Mori, Tabito Tonooka, Takashi Yamagajo
  • Patent number: 10587045
    Abstract: An antenna device includes: a ground plane having an edge; a matching circuit; and a T-shaped antenna element including a first element and a second element extending from a feed point to a first and second end parts. The first element has a resonance frequency that is higher than a first frequency. The second element has a resonance frequency between a second frequency and a third frequency. A first value obtained by dividing a length from a corresponding point to a first bend part by the first wavelength is less than or equal to a second value obtained by dividing a length from the corresponding point to a second bend part by the second wavelength. An imaginary component of an impedance of the matching circuit takes a positive value at the first frequency and the second frequency and takes a negative value at the third frequency.
    Type: Grant
    Filed: July 26, 2018
    Date of Patent: March 10, 2020
    Assignee: FUJITSU LIMITED
    Inventors: Takashi Yamagajo, Yohei Koga, Manabu Kai, Tabito Tonooka, Minoru Sakurai, Mitsuharu Hoshino
  • Patent number: 10476161
    Abstract: A loop antenna includes: a substrate; a feeding element including a first portion and a second portion which are provided on a first surface of the substrate, have electrical conductivity, are fed with electric power from a feeding point, the first portion extending from the feeding point in a first direction, the second portion extending from the feeding point in a second direction; and an emitting element which has electrical conductivity, is formed in a loop shape in such a manner that the emitting element surrounds the substrate along a surface perpendicular to the first surface, and includes a first end provided so as to electromagnetically couple to the first portion on the first surface and a second end provided so as to electromagnetically couple to the second portion on the first surface, a gap being disposed between the first end and the second end.
    Type: Grant
    Filed: May 31, 2018
    Date of Patent: November 12, 2019
    Assignee: FUJITSU LIMITED
    Inventors: Takashi Yamagajo, Manabu Kai
  • Publication number: 20190341675
    Abstract: An antenna device includes a ground plane that includes an edge and a surface, a protruding metallic member that includes a first connecting part and a second connecting part coupled to the ground plane, protrudes from the edge, and constructs a first loop including the edge, and a T-shaped antenna element that extends from a feeding point to a first end and a second end along the edge, the feeding point being disposed in the vicinity of the surface between the first connecting part and the second connecting part of the first loop, wherein a length of the first loop corresponds to an electric length of one wavelength in a first frequency, and corresponds to an electric length of two wavelengths in a second frequency that is a second order harmonic of the first frequency.
    Type: Application
    Filed: April 3, 2019
    Publication date: November 7, 2019
    Applicant: Fujitsu Limited
    Inventors: Takashi YAMAGAJO, Yohei Koga, Manabu Yoshikawa, Tabito Tonooka, Hirotake Sumi
  • Patent number: 10452808
    Abstract: A non-transitory computer-readable storage medium storing an antenna design program that causes a computer to execute a process, the process including acquiring a target characteristic value of a target antenna when a value of a structure parameter is a predetermined value, based on the predetermined value of the structure parameter, the target characteristic value, and a relation, with respect to a reference antenna, between a value of a structure parameter and a characteristic value, estimating the relation with respect to the target antenna, the reference antenna having a same shape feature as the target antenna, an antenna type of the reference antenna being different from the target antenna, determining a value of the structure parameter for the target antenna such that the characteristic value of the target antenna satisfies a demanded specification based on the estimated relation, and outputting the determined value of the structure parameter.
    Type: Grant
    Filed: February 8, 2017
    Date of Patent: October 22, 2019
    Assignee: Fujitsu Limited
    Inventors: Yohei Koga, Manabu Kai, Takashi Yamagajo, Yasumitsu Ban, Hiroyuki Egawa, Kan Fujieda
  • Patent number: 10454176
    Abstract: An antenna apparatus includes a ground plane having an edge; a monopole type first antenna element having a first feed point and configured to communicate at a first frequency; and a monopole type second antenna element having a second feed point and configured to communicate at a second frequency, the second antenna element extending from the second feed point in a direction away from the edge. An end portion of the first antenna element is arranged closer to the ground plane than an end portion of the second antenna element is. A length of an interval between the first feed point and the second feed point is in a range of from 0.25-fold to 0.7-fold of an electrical length of a first wavelength at the first frequency. A length of the second antenna element is a length in a range of from 0.15-fold to 0.55-fold of the electrical length.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: October 22, 2019
    Assignee: FUJITSU LIMITED
    Inventors: Yohei Koga, Takashi Yamagajo, Manabu Kai, Mitsuharu Hoshino, Masatomo Mori
  • Publication number: 20190286765
    Abstract: An antenna design apparatus includes a memory; and a processor coupled to the memory, wherein the processor calculates at least one circuit element value of a matching circuit for an antenna including loss resistance using S parameter data stored in the memory, obtains combined S parameter data in which a portion of the loss resistance of the matching circuit is incorporated in characteristics of the antenna by calculating the S parameter data while loss resistance of one of the calculated at least one circuit element value of the matching circuit which is disposed on a port side is incorporated in the characteristics of the antenna, and recalculates the at least one circuit element value of the matching circuit when the matching circuit is coupled to the antenna such that the at least one circuit element value matches the combined S parameter.
    Type: Application
    Filed: January 15, 2019
    Publication date: September 19, 2019
    Applicant: FUJITSU LIMITED
    Inventors: Takashi YAMAGAJO, Sotaro KURIBAYASHI, Manabu KAI
  • Publication number: 20190214725
    Abstract: A multiband antenna includes a ground conductor, a first conductor disposed at a predetermined distance from the ground conductor, formed linearly, and configured to have a length to resonate at first and second frequencies, the first conductor including a power feeding point, a second conductor coupled to the first conductor at both ends of the second conductor, disposed closer to a side of the ground conductor than the first conductor, formed linearly, and configured to form a slit between the first and second conductors and resonate together with the first conductor at a third frequency, and a third conductor provided at one or more ends of the first conductor and configured to extend from a first end of the one or more ends to the side of the ground conductor to be electromagnetically coupled to the ground conductor at the third frequency, wherein the conductors has conductivity.
    Type: Application
    Filed: March 18, 2019
    Publication date: July 11, 2019
    Applicant: FUJITSU LIMITED
    Inventors: Yohei KOGA, Manabu KAI, Masatomo MORI, Tabito TONOOKA, Takashi YAMAGAJO
  • Publication number: 20190214726
    Abstract: An antenna device includes a ground plane having an edge side, a monopole antenna element that communicates in a first frequency, and that has a first feeding point, a first line that extends from the first feeding point in a direction away from the edge side of the ground plane, and a second line that is coupled to the first line and extends along the edge side, a plurality of dipole feeding elements that communicate at a second frequency higher than the first frequency, and are disposed, with respect to the ground plane, in positions that match the positions of the second line with respect to the ground plane, and a plurality of reflectors that reflect electromagnetic waves radiated by the plurality of feeding elements, and are disposed respectively in correspondence to the plurality of feeding elements between the ground plane and the plurality of feeding elements.
    Type: Application
    Filed: December 20, 2018
    Publication date: July 11, 2019
    Applicant: FUJITSU LIMITED
    Inventors: Takashi YAMAGAJO, Manabu Kai, Yohei Koga, Tablto Tonooka, Hirotake Sumi
  • Publication number: 20190190124
    Abstract: An antenna device includes: a ground plane which has an edge side; a metal member arranged along the edge side of the ground plane; a first connection line which couples the metal member and the ground plane; a second connection line which couples the metal member and the ground plane; and a power feeding element which has a power feeding point, extends along the metal member from the power feeding point between the first connection line and the second connection line, and is electromagnetic-field-coupled to the metal member.
    Type: Application
    Filed: February 26, 2019
    Publication date: June 20, 2019
    Applicant: FUJITSU LIMITED
    Inventors: Yohei KOGA, Takashi YAMAGAJO, Manabu KAI, Tabito TONOOKA
  • Publication number: 20180366827
    Abstract: A loop antenna includes: a substrate; a feeding element including a first portion and a second portion which are provided on a first surface of the substrate, have electrical conductivity, are fed with electric power from a feeding point, the first portion extending from the feeding point in a first direction, the second portion extending from the feeding point in a second direction; and an emitting element which has electrical conductivity, is formed in a loop shape in such a manner that the emitting element surrounds the substrate along a surface perpendicular to the first surface, and includes a first end provided so as to electromagnetically couple to the first portion on the first surface and a second end provided so as to electromagnetically couple to the second portion on the first surface, a gap being disposed between the first end and the second end.
    Type: Application
    Filed: May 31, 2018
    Publication date: December 20, 2018
    Applicant: FUJITSU LIMITED
    Inventors: Takashi YAMAGAJO, Manabu Kai
  • Publication number: 20180358700
    Abstract: An antenna device includes: a ground plane having an edge; a matching circuit; and a T-shaped antenna element including a first element and a second element extending from a feed point to a first and second end parts. The first element has a resonance frequency that is higher than a first frequency. The second element has a resonance frequency between a second frequency and a third frequency. A first value obtained by dividing a length from a corresponding point to a first bend part by the first wavelength is less than or equal to a second value obtained by dividing a length from the corresponding point to a second bend part by the second wavelength. An imaginary component of an impedance of the matching circuit takes a positive value at the first frequency and the second frequency and takes a negative value at the third frequency.
    Type: Application
    Filed: July 26, 2018
    Publication date: December 13, 2018
    Applicant: FUJITSU LIMITED
    Inventors: Takashi YAMAGAJO, Yohei Koga, Manabu Kai, Tabito Tonooka, Minoru Sakurai, Mitsuharu Hoshino
  • Publication number: 20180287249
    Abstract: An antenna apparatus includes: a ground plane having a slit extending from an edge to an inside first point and extending, along the edge, to a second point; a first antenna element having a first feed point and a first open end, the first feed point being arranged at an opposite side of an area surrounded by the slit and the edge with respect to the slit, the first antennae element extending from the first feed point to a first bend part at a first height position and extending to the first open end; and a second antenna element having a second feed point, arranged in the area, and a second open end, and extending from the second feed point to a second bend part at a second height position, extending to the second open end, and crossing, at a second open end side, the slit.
    Type: Application
    Filed: March 6, 2018
    Publication date: October 4, 2018
    Applicant: FUJITSU LIMITED
    Inventors: Takashi YAMAGAJO, Yohei Koga, Manabu Kai, Masatomo Mori, Tabito Tonooka, Mitsuharu Hoshino
  • Publication number: 20180183149
    Abstract: An antenna apparatus includes a ground plane having an edge; a monopole type first antenna element having a first feed point and configured to communicate at a first frequency; and a monopole type second antenna element having a second feed point and configured to communicate at a second frequency, the second antenna element extending from the second feed point in a direction away from the edge. An end portion of the first antenna element is arranged closer to the ground plane than an end portion of the second antenna element is. A length of an interval between the first feed point and the second feed point is in a range of from 0.25-fold to 0.7-fold of an electrical length of a first wavelength at the first frequency. A length of the second antenna element is a length in a range of from 0.15-fold to 0.55-fold of the electrical length.
    Type: Application
    Filed: December 5, 2017
    Publication date: June 28, 2018
    Applicant: FUJITSU LIMITED
    Inventors: Yohei KOGA, Takashi YAMAGAJO, Manabu KAI, Mitsuharu HOSHINO, Masatomo MORI
  • Publication number: 20180097276
    Abstract: An antenna apparatus includes a ground plane having an edge; a feed element having a feed point located close to the edge and a first open end, the feed element extending from the feed point to the first open end and serving as an inductor; a parasitic element having a second open end disposed a predetermined distance away from the first open end and a connection end connected to the edge, the parasitic element extending from the connection end to the second open end, a length from the connection end to the second open end being set to be a quarter wavelength of an electrical length of a wavelength in a communication frequency; and a metal member disposed between the first second open ends via a predetermined interval to cover the first and second open ends to constitute a predetermined capacity between the first and second open ends.
    Type: Application
    Filed: September 15, 2017
    Publication date: April 5, 2018
    Applicant: FUJITSU LIMITED
    Inventors: Takashi Yamagajo, Manabu Kai
  • Patent number: 9905939
    Abstract: An antenna device includes: a first antenna element configured to radiate first radio waves having a first plane of polarization; and a second antenna element configured to radiate second radio waves having a second plane of polarization orthogonal to the first plane of polarization, wherein ends of the first antenna element and the second antenna element located at mutually approaching sides are disposed in a positional relationship, and a phase deviation caused by an electromagnetic coupling based on the positional relationship is compensated and an electrical power is fed to the first antenna element and the second antenna element with a phase difference that causes a composite wave of the first radio waves and the second radio waves to form a circularly polarized wave.
    Type: Grant
    Filed: November 30, 2015
    Date of Patent: February 27, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Takashi Yamagajo, Masahiko Shimizu, Makoto Yoshida