Patents by Inventor Tatsuo Furuno

Tatsuo Furuno 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: 9385892
    Abstract: There is provided a communication system capable of achieving a high usage efficiency of frequencies without the need for cooperation of multiplexed users. A communication system communicates over frequency channels set by dividing a frequency bandwidth assigned to the system allows interference between channels by overlapping the adjacent frequency channels with each other in the frequency domain, or a transmitting and receiving device, which transmits and receives a signal by allowing the interference between symbols at a waveform level for each channel to decrease the occupied bandwidth, is provided with ICI removal and ISI compensation filter 111 serving as either an ICI removal filter for removing the interference between channels or an ISI compensation filter for compensating the interference between symbols.
    Type: Grant
    Filed: May 9, 2013
    Date of Patent: July 5, 2016
    Assignee: NTT DoCoMo, Inc.
    Inventors: Anass Benjebbour, Takahiro Asai, Hitoshi Yoshino, Tatsuo Furuno, Tomoyuki Ooya
  • Patent number: 9337942
    Abstract: A propagation path estimation method using an imaging method according to the invention includes a step of, in a case where a reflectarray which causes reflection and scattering in a different direction (???)° from a specular reflection direction ?° exists on a propagation path from a transmission point to a reception point RX of the radio wave, calculating a virtual reception point VRX by rotating the reception point RX about a rotation center point O, and estimating the propagation path by using the virtual reception point VRX.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: May 10, 2016
    Assignee: NTT DOCOMO, INC.
    Inventors: Tamami Maruyama, Tatsuo Furuno, Tomoyuki Ohya, Yasuhiro Oda, Ngoc Hao Tran, Jiyun Shen
  • Patent number: 9264157
    Abstract: A propagation path estimation method using an imaging method according to the invention includes a step of, in a case where a reflect array 1 (structure) which causes reflection and scattering in a predetermined direction (?-?)° different from a specular reflection direction ?° exists on a propagation path, rotating the reflect array 1 by ?/2° about a rotation center O to set a virtual rotated reflect array 2 (virtual structure), and estimating the propagation path by using the virtual rotated reflect array 2.
    Type: Grant
    Filed: December 3, 2010
    Date of Patent: February 16, 2016
    Assignee: NTT DOCOMO, INC.
    Inventors: Tamami Maruyama, Tatsuo Furuno, Tomoyuki Ohya, Jiyun Shen, Yasuhiro Oda, Ngoc Hao Tran
  • Patent number: 8988287
    Abstract: An apparatus having multiple mushroom structures is disclosed. Each of the multiple mushroom structures includes: a ground plate; a patch provided parallel to the ground plate with a separation of a distance to the ground plate, wherein a distance between a ground plate and a patch in a certain mushroom structure is different from a distance between a ground plate and a patch in a different mushroom structure.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: March 24, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Tamami Maruyama, Tatsuo Furuno, Yasuhiro Oda, Jiyun Shen, Tomoyuki Ohya
  • Patent number: 8952849
    Abstract: An apparatus having multiple mushroom structures is disclosed. Each of the multiple mushroom structures includes: a ground plate; a patch provided parallel to the ground plate with a separation of a distance to the ground plate, wherein a distance between a ground plate and a patch in a certain mushroom structure is different from a distance between a ground plate and a patch in a different mushroom structure.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: February 10, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Tamami Maruyama, Tatsuo Furuno, Yasuhiro Oda, Jiyun Shen, Tomoyuki Ohya
  • Patent number: 8847822
    Abstract: An apparatus having multiple mushroom structures is disclosed. Each of the multiple mushroom structures including: a ground plate; a first patch provided parallel to the ground plate with a separation of a distance to the ground plate; and a second patch provided parallel to the ground plate with a separation of another distance to the ground plate, which another distance being different from the distance from the first patch to the ground plate, wherein the second patch is a passive element which is capacitatively coupled with at least the first patch.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: September 30, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Tamami Maruyama, Tatsuo Furuno, Yasuhiro Oda, Jiyun Shen, Tomoyuki Ohya
  • Patent number: 8836583
    Abstract: A reflectarray, including: a substrate; and a plurality of patches formed on each of areas into which a principal surface of the substrate is divided, wherein the plurality of patches are formed by including a gap.
    Type: Grant
    Filed: August 24, 2011
    Date of Patent: September 16, 2014
    Assignees: NTT DoCoMo, Inc., Tohoku University
    Inventors: Tamami Maruyama, Tomoyuki Ohya, Tatsuo Furuno, Kunio Sawaya, Qiang Chen, Jianfeng Li, Shiwei Qu, Qiaowei Yuan
  • Patent number: 8830126
    Abstract: An apparatus having multiple mushroom structures is disclosed. Each of the multiple mushroom structures includes: a ground plate; a first patch provided parallel to the ground plate with a separation of a distance to the ground plate; and a second patch provided parallel to the ground plate with a separation of another distance to the ground plate, which another distance being different from the distance from the first patch to the ground plate, wherein the second patch is a passive element which is capacitatively coupled with at least the first patch.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: September 9, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Tamami Maruyama, Tatsuo Furuno, Yasuhiro Oda, Jiyun Shen, Tomoyuki Ohya
  • Patent number: 8779984
    Abstract: An apparatus having multiple mushroom structures is disclosed. Each of the multiple mushroom structures includes: a ground plate; a first patch provided parallel to the ground plate with a separation of a distance to the ground plate; and a second patch provided parallel to the ground plate with a separation of another distance to the ground plate, which another distance being different from the distance from the first patch to the ground plate, wherein the second patch is a passive element which is capacitatively coupled with at least the first patch.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: July 15, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Tamami Maruyama, Tatsuo Furuno, Yasuhiro Oda, Jiyun Shen, Tomoyuki Ohya
  • Patent number: 8693527
    Abstract: A relay apparatus is disclosed for relaying a signal from a transmitter to a receiver in a MIMO (Multiple Input Multiple Output) based communication system, comprising: a power difference determination unit configured to determine a difference of reception levels between a direct wave and a relayed wave based on positional relationship among the transmitter, the relay apparatus and the receiver, the direct wave traveling from the transmitter to the receiver without the relay apparatus, the relayed wave traveling from the transmitter to the receiver via the relay apparatus; a gain determination unit configured to determine an amplification gain of the relay apparatus to make the difference smaller; and a transmitting unit configured to amplify the signal from the transmitter at the determined amplification gain and transmit the amplified signal to the receiver.
    Type: Grant
    Filed: September 1, 2011
    Date of Patent: April 8, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Jiyun Shen, Yasuhiro Oda, Tamami Maruyama, Tatsuo Furuno, Tomoyuki Ohya
  • Patent number: 8649742
    Abstract: A radio communication system according to the present invention includes a scatterer configured to reflect, refract, or transmit a radio wave radiated primarily from a transmission side apparatus to radiate the radio wave secondarily to a desired area and a metamaterial is used for the scatterer.
    Type: Grant
    Filed: November 28, 2008
    Date of Patent: February 11, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Tamami Maruyama, Shinji Uebayashi, Tatsuo Furuno
  • Patent number: 8588325
    Abstract: A communication system capable of achieving a high usage efficiency of frequencies without the need for cooperation of multiplexed users is disclosed. The communication system communicates over frequency channels set by dividing a frequency bandwidth assigned to the system and allows interference between channels by overlapping the adjacent frequency channels with each other in the frequency domain. A transmitting and receiving device, which transmits and receives a signal by allowing the interference between symbols at a waveform level for each channel to decrease the occupied bandwidth, is provided. The receiving device is provided with an Inter-Channel Interference (ICI) removal and Inter-Symbol Interference (ISI) compensation filter serving as either an ICI removal filter for removing the interference between channels or an ISI compensation filter for compensating the interference between symbols.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: November 19, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Anass Benjebbour, Takahiro Asai, Hitoshi Yoshino, Tatsuo Furuno, Tomoyuki Ooya
  • Patent number: 8390531
    Abstract: A reflect array (1) according to the present invention includes a plurality of array elements (10) forming an array configured to control a direction of a reflected wave (scattered wave) by controlling a phase of the reflected wave; and a ground plane (30). The ground plane (30) has a structure with a frequency selective function.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: March 5, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Tamami Maruyama, Shinji Uebayashi, Tatsuo Furuno, Long Li, Qiang Chen, Qiaowei Yuan, Kunio Sawaya
  • Publication number: 20120303328
    Abstract: A propagation path estimation method using an imaging method according to the invention includes a step of, in a case where a reflect array 1 (structure) which causes reflection and scattering in a predetermined direction (?-?)° different from a specular reflection direction ?° exists on a propagation path, rotating the reflect array 1 by ?/2° about a rotation center O to set a virtual rotated reflect array 2 (virtual structure), and estimating the propagation path by using the virtual rotated reflect array 2.
    Type: Application
    Filed: December 3, 2010
    Publication date: November 29, 2012
    Applicant: NTT DOCOMO, INC
    Inventors: Tamami Maruyama, Tatsuo Furuno, Tomoyuki Ohya, Jiyun Shen, Yasuhiro Oda, Ngoc Hao Tran
  • Publication number: 20120302177
    Abstract: A propagation path estimation method using an imaging method according to the invention includes a step of, in a case where a reflectarray which causes reflection and scattering in a different direction (???)° from a specular reflection direction ?° exists on a propagation path from a transmission point to a reception point RX of the radio wave, calculating a virtual reception point VRX by rotating the reception point RX about a rotation center point O, and estimating the propagation path by using the virtual reception point VRX.
    Type: Application
    Filed: December 6, 2010
    Publication date: November 29, 2012
    Applicant: NTT DOCOMO, INC.
    Inventors: Tamami Maruyama, Tatsuo Furuno, Tomoyuki Ohya, Yasuhiro Oda, Ngoc Hao Tran, Jiyun Shen
  • Patent number: 8289220
    Abstract: The present invention relates to a radio communication system configured to secondarily-radiate, to a desired area by reflection, primarily-radiated radio waves from a transmitter apparatus, by using a reflector plate for controlling phases of reflected waves, wherein a reflecting property of the reflector plate is set so that the reflector plate reflects the primarily-radiated radio waves as plane waves of equal phase directed to a direction different from a reflection angle in the case of specular reflection.
    Type: Grant
    Filed: September 1, 2009
    Date of Patent: October 16, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Tamami Maruyama, Shinji Uebayashi, Tatsuo Furuno
  • Publication number: 20120105305
    Abstract: A reflectarray according to the present invention formed by arranging a plurality of mushroom structures on a ground plane and each of the mushroom structures is formed by one quadrilateral patch and a via configured to short the patch and the ground plane. The adjacent vias are arranged to have equal intervals in a vertical direction of the ground plane. A size of each gap between the adjacent patches is adjusted so that a value of a reflection phase of a reflected wave from can of the patches is set to a desired value.
    Type: Application
    Filed: May 28, 2010
    Publication date: May 3, 2012
    Applicant: NTT DOCOMO, INC.
    Inventors: Tamami Maruyama, Tatsuo Furuno, Tomoyuki Ohya, Shinji Uebayashi, Koji Isshiki
  • Publication number: 20120057619
    Abstract: A relay apparatus is disclosed for relaying a signal from a transmitter to a receiver in a MIMO (Multiple Input Multiple Output) based communication system, comprising: a power difference determination unit configured to determine a difference of reception levels between a direct wave and a relayed wave based on positional relationship among the transmitter, the relay apparatus and the receiver, the direct wave traveling from the transmitter to the receiver without the relay apparatus, the relayed wave traveling from the transmitter to the receiver via the relay apparatus; a gain determination unit configured to determine an amplification gain of the relay apparatus to make the difference smaller; and a transmitting unit configured to amplify the signal from the transmitter at the determined amplification gain and transmit the amplified signal to the receiver.
    Type: Application
    Filed: September 1, 2011
    Publication date: March 8, 2012
    Applicant: NTT DOCOMO, INC.
    Inventors: Jiyun Shen, Yasuhiro Oda, Tamami Maruyama, Tatsuo Furuno, Tomoyuki Ohya
  • Publication number: 20120050127
    Abstract: A reflectarray, including: a substrate; and a plurality of patches formed on each of areas into which a principal surface of the substrate is divided, wherein the plurality of patches are formed by including a gap.
    Type: Application
    Filed: August 24, 2011
    Publication date: March 1, 2012
    Applicants: TOHOKU UNIVERSITY, NTT DOCOMO, INC.
    Inventors: Tamami MARUYAMA, Tomoyuki Ohya, Tatsuo Furuno, Kunio Sawaya, Qiang Chen, Jianfeng Li, Shiwei Qu, Qiaowei Yuan
  • Publication number: 20110210906
    Abstract: An apparatus having multiple mushroom structures is disclosed. Each of the multiple mushroom structures includes: a ground plate; a first patch provided parallel to the ground plate with a separation of a distance to the ground plate; and a second patch provided parallel to the ground plate with a separation of another distance to the ground plate, which another distance being different from the distance from the first patch to the ground plate, wherein the second patch is a passive element which is capacitatively coupled with at least the first patch.
    Type: Application
    Filed: February 22, 2011
    Publication date: September 1, 2011
    Applicant: NTT DOCOMO, INC.
    Inventors: Tamami MARUYAMA, Tatsuo Furuno, Yasuhiro Oda, Jiyun Shen, Tomoyuki Ohya