Patents by Inventor Yoshifumi Morihiro

Yoshifumi Morihiro 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: 11184844
    Abstract: In user terminal 10 of the present invention, connection-cell-selection controlling section 110 measures reception quality of signals respectively transmitted from cells and received by antenna section 108, corrects the reception quality of each of the cells based on a positional relationship between each of the cells and user terminal 10 and based on a moving direction of user terminal 10, and determines a connection cell for user terminal 10 (base station in communication with user terminal 10) based on the corrected reception quality. This configuration lowers a cell switching frequency, while preventing degradation of throughput and the like in a future radio communication system (multilayer cellular radio network).
    Type: Grant
    Filed: December 18, 2017
    Date of Patent: November 23, 2021
    Assignee: NTT DOCOMO, INC.
    Inventors: Akira Kishida, Yoshifumi Morihiro, Takahiro Asai, Yukihiko Okumura
  • Patent number: 11153919
    Abstract: An AP and UE, which perform access control using CSMA/CA, perform a step judging an exposed level in transmission of the AP based on a congesting level in transmission, which is caused by a wireless station in defer transmission that is in a neighborhood of the AP; a step judging an exposed level in reception of the UE based on a congesting level in reception, which is caused by a wireless station in defer transmission that is in a neighborhood of the UE; and a step performing control which changes a channel of the AP, when the exposed level in transmission cannot satisfy expected quality of the AP, and performing control which changes a connected AP of the UE, or control which changes to other network, when the exposed level in transmission or in reception cannot satisfy required quality of the UE or the expected quality of the AP.
    Type: Grant
    Filed: March 28, 2018
    Date of Patent: October 19, 2021
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akiyoshi Inoki, Hirantha Abeysekera, Munehiro Matsui, Kenichi Kawamura, Yasushi Takatori, Takeo Ichikawa, Akira Kishida, Yoshifumi Morihiro, Takahiro Asai
  • Patent number: 11044754
    Abstract: A wireless user equipment performing wireless communication in a primary and a secondary frequency bands, a first wireless access point AP performing the wireless communication in the primary frequency band, and a second wireless base transceiver station BTS performing the wireless communication in the secondary frequency band are included. The AP and the BTS are connected to each other through a network. A UD report transfer unit transfers a UD report including information relating to transmission-waiting user data destined for a receiving node. The receiving node includes a transmission opportunity control unit which sets a fixed transmission prohibition time in a channel in the primary frequency band for a wireless communication device in a vicinity, obtains a transmission opportunity, grants the transmission opportunity to the transmitting node, and causes the user data to be transmitted from the transmitting node according to the transferred UD report.
    Type: Grant
    Filed: February 23, 2016
    Date of Patent: June 22, 2021
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Riichi Kudo, Hirantha Sithira Abeysekera, Yasushi Takatori, Takeo Ichikawa, Masato Mizoguchi, Yasufumi Morioka, Hiroto Yasuda, Akira Yamada, Yoshifumi Morihiro, Yukihiko Okumura
  • Patent number: 10681735
    Abstract: Provided is a wireless environment evaluation method including a step 1 acquiring a transmission and reception history of wireless signals transmitted and received between the plurality of wireless stations and acquiring or estimating a number of wireless stations in transmission standby, based on the transmission and reception history; a step 2 calculating a normal reception rate S in a congesting situation in reception according to the number of wireless stations in transmission standby; a step 3 acquiring a normal reception rate S? of the wireless signals per a fixed channel use time from the transmission and reception history in the prescribed wireless station; and a step 4 determining a degree of the exposed situation in reception according to a ratio of the normal reception rate S? to the normal reception rate S.
    Type: Grant
    Filed: February 23, 2017
    Date of Patent: June 9, 2020
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akiyoshi Inoki, Hirantha Abeysekera, Munehiro Matsui, Takeo Ichikawa, Masato Mizoguchi, Akira Kishida, Daisuke Koizumi, Akira Yamada, Yoshifumi Morihiro, Takahiro Asai
  • Publication number: 20200053774
    Abstract: An AP and UE, which perform access control using CSMA/CA, perform a step judging an exposed level in transmission of the AP based on a congesting level in transmission, which is caused by a wireless station in defer transmission that is in a neighborhood of the AP; a step judging an exposed level in reception of the UE based on a congesting level in reception, which is caused by a wireless station in defer transmission that is in a neighborhood of the UE; and a step performing control which changes a channel of the AP, when the exposed level in transmission cannot satisfy expected quality of the AP, and performing control which changes a connected AP of the UE, or control which changes to other network, when the exposed level in transmission or in reception cannot satisfy required quality of the UE or the expected quality of the AP.
    Type: Application
    Filed: March 28, 2018
    Publication date: February 13, 2020
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akiyoshi INOKI, Hirantha ABEYSEKERA, Munehiro MATSUI, Kenichi KAWAMURA, Yasushi TAKATORI, Takeo ICHIKAWA, Akira KISHIDA, Yoshifumi MORIHIRO, Takahiro ASAI
  • Publication number: 20190387467
    Abstract: In user terminal 10 of the present invention, connection-cell-selection controlling section 110 measures reception quality of signals respectively transmitted from cells and received by antenna section 108, corrects the reception quality of each of the cells based on a positional relationship between each of the cells and user terminal 10 and based on a moving direction of user terminal 10, and determines a connection cell for user terminal 10 (base station in communication with user terminal 10) based on the corrected reception quality. This configuration lowers a cell switching frequency, while preventing degradation of throughput and the like in a future radio communication system (multilayer cellular radio network).
    Type: Application
    Filed: December 18, 2017
    Publication date: December 19, 2019
    Applicant: NTT DOCOMO, INC.
    Inventors: Akira Kishida, Yoshifumi Morihiro, Takahiro Asai, Yukihiko Okumura
  • Patent number: 10484917
    Abstract: A communication apparatus in a wireless communication system in which a plurality of cells with different bands are overlaid and which includes the communication apparatus and a user equipment include: an acquisition unit configured to acquire communication quality of the user equipment in a first cell in which the user equipment resides; a determination unit configured to determine whether to perform the switch to a second cell overlaid with the first cell based on the communication quality of the user equipment; and an instruction unit configured to instruct the user equipment to perform the switch to the second cell when the switch to the second cell overlaid with the first cell is determined.
    Type: Grant
    Filed: February 15, 2017
    Date of Patent: November 19, 2019
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshifumi Morihiro, Takahiro Asai
  • Publication number: 20190116532
    Abstract: A communication apparatus in a wireless communication system in which a plurality of cells with different bands are overlaid and which includes the communication apparatus and a user equipment include: an acquisition unit configured to acquire communication quality of the user equipment in a first cell in which the user equipment resides; a determination unit configured to determine whether to perform the switch to a second cell overlaid with the first cell based on the communication quality of the user equipment; and an instruction unit configured to instruct the user equipment to perform the switch to the second cell when the switch to the second cell overlaid with the first cell is determined.
    Type: Application
    Filed: February 15, 2017
    Publication date: April 18, 2019
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshifumi MORIHIRO, Takahiro ASAI
  • Publication number: 20190059107
    Abstract: Provided is a wireless environment evaluation method including a step 1 acquiring a transmission and reception history of wireless signals transmitted and received between the plurality of wireless stations and acquiring or estimating a number of wireless stations in transmission standby, based on the transmission and reception history; a step 2 calculating a normal reception rate S in a congesting situation in reception according to the number of wireless stations in transmission standby; a step 3 acquiring a normal reception rate S? of the wireless signals per a fixed channel use time from the transmission and reception history in the prescribed wireless station; and a step 4 determining a degree of the exposed situation in reception according to a ratio of the normal reception rate S? to the normal reception rate S.
    Type: Application
    Filed: February 23, 2017
    Publication date: February 21, 2019
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akiyoshi INOKI, Hirantha Sithira ABEYSEKERA, Munehiro MATSUI, Takeo ICHIKAWA, Masato MIZOGUCHI, Akira KISHIDA, Daisuke KOIZUMI, Akira YAMADA, Yoshifumi MORIHIRO, Takahiro ASAI
  • Patent number: 10003978
    Abstract: A mobile communication system that includes a first communication system, which features a user terminal that is present in a moving object, a first radio base station that forms a cell in the moving object, and a first core network that is connected with an external network, and a second communication system, which features a radio mobile station that is provided in the moving object, a second radio base station that forms a cell on the path of the movement of the moving object, and a second core network that is connected with the second radio base station. The first radio base station and the radio mobile station are connected via a user-plane interface and a control-plane interface between the radio base stations and the core networks.
    Type: Grant
    Filed: December 10, 2014
    Date of Patent: June 19, 2018
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshifumi Morihiro, Satoshi Suyama, Jiyun Shen, Yukihiko Okumura
  • Publication number: 20180035467
    Abstract: A wireless user equipment performing wireless communication in a primary and a secondary frequency bands, a first wireless access point AP performing the wireless communication in the primary frequency band, and a second wireless base transceiver station BTS performing the wireless communication in the secondary frequency band are included. The AP and the BTS are connected to each other through a network. A UD report transfer unit transfers a UD report including information relating to transmission-waiting user data destined for a receiving node. The receiving node includes a transmission opportunity control unit which sets a fixed transmission prohibition time in a channel in the primary frequency band for a wireless communication device in a vicinity, obtains a transmission opportunity, grants the transmission opportunity to the transmitting node, and causes the user data to be transmitted from the transmitting node according to the transferred UD report.
    Type: Application
    Filed: February 23, 2016
    Publication date: February 1, 2018
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Riichi KUDO, Hirantha Sithira ABEYSEKERA, Yasushi TAKATORI, Takeo ICHIKAWA, Masato MIZOGUCHI, Yasufumi MORIOKA, Hiroto YASUDA, Akira YAMADA, Yoshifumi MORIHIRO, Yukihiko OKUMURA
  • Patent number: 9801012
    Abstract: A radio communication system includes: a visit information storage unit that stores plural visit information elements each indicating information on a visit to a cell visited by a user equipment; an event detector that detects an event that occurs in the user equipment; a cell identifier detector that detects a cell identifier that indicates a cell visited by the user equipment; and a location characteristic determiner that determines a location characteristic of the cell indicated by the cell identifier based on one or more visit information elements corresponding to the cell. The location to characteristic determiner determines the location characteristic of a cell visited by the user equipment when the event detector detects a no-cell-change event other than a cell-change event that indicates a change in the cell identifier.
    Type: Grant
    Filed: June 10, 2014
    Date of Patent: October 24, 2017
    Assignee: NTT DOCOMO, INC.
    Inventors: Yasufumi Morioka, Kouki Hayashi, Masanori Ishida, Yoshifumi Morihiro
  • Patent number: 9736632
    Abstract: A user apparatus includes processing modules that execute processing using basic area information, and an area information supply module that supplies basic area information to the processing modules. The area information supply module includes an event detection unit that detects an event, an area information acquisition unit that acquires basic area information in accordance with an event being detected, and an area information notification unit that notifies the processing modules of the basic area information. The area information acquisition unit acquires detailed area information in accordance with a request signal being received. The area information notification unit notifies a processing module of the detailed area information.
    Type: Grant
    Filed: June 10, 2014
    Date of Patent: August 15, 2017
    Assignee: NTT DOCOMO, INC.
    Inventors: Yasufumi Morioka, Kouki Hayashi, Masanori Ishida, Yoshifumi Morihiro
  • Patent number: 9736750
    Abstract: A radio communication system includes: a visit information storage unit that stores plural visit information elements each indicating information on a visit to a cell visited by a user equipment; a cell visit detector that detects that the user equipment that was visiting a first cell starts a visit to a second cell differing from the first cell; a ping-ponging state determiner that determines whether a ping-ponging state has occurred, in which state start and ending of a visit to the second cell is repeated, wherein the determination is made based on a visit information element on a visit to the second cell visited by the user equipment; and a calculator that calculates a visit time length of the visit to the second cell in accordance with the determination by the ping-ponging state determiner.
    Type: Grant
    Filed: May 1, 2014
    Date of Patent: August 15, 2017
    Assignee: NTT DOCOMO, INC.
    Inventors: Yasufumi Morioka, Kouki Hayashi, Yoshifumi Morihiro
  • Publication number: 20170094528
    Abstract: A user terminal that can communicate with a radio base station by using a licensed band and an unlicensed band is disclosed. The user terminal includes a receiving section that receives downlink signals transmitted in the licensed band and the unlicensed band, a measurement section that measures a downlink signal transmitted in the unlicensed band, and a control section that controls feedback of a measurement result. The receiving section receives information related to a command for the measurement in the unlicensed band and/or a command for the feedback of the measurement result by using the licensed band.
    Type: Application
    Filed: May 13, 2015
    Publication date: March 30, 2017
    Applicant: NTT DOCOMO, INC.
    Inventors: Kazuaki Takeda, Yoshifumi Morihiro, Hiroki Harada, Satoshi Nagata, Kazuki Takeda
  • Publication number: 20160381568
    Abstract: A mobile communication system that includes a first communication system, which features a user terminal that is present in a moving object, a first radio base station that forms a cell in the moving object, and a first core network that is connected with an external network, and a second communication system, which features a radio mobile station that is provided in the moving object, a second radio base station that forms a cell on the path of the movement of the moving object, and a second core network that is connected with the second radio base station. The first radio base station and the radio mobile station are connected via a user-plane interface and a control-plane interface between the radio base stations and the core networks.
    Type: Application
    Filed: December 10, 2014
    Publication date: December 29, 2016
    Applicant: NTT DOCOMO, INC.
    Inventors: Yoshifumi Morihiro, Satoshi Suyama, Jiyun Shen, Yukihiko Okumura
  • Publication number: 20160174026
    Abstract: A radio communication system includes: a visit information storage unit that stores plural visit information elements each indicating information on a visit to a cell visited by a user equipment; an event detector that detects an event that occurs in the user equipment; a cell identifier detector that detects a cell identifier that indicates a cell visited by the user equipment; and a location characteristic determiner that determines a location characteristic of the cell indicated by the cell identifier based on one or more visit information elements corresponding to the cell. The location to characteristic determiner determines the location characteristic of a cell visited by the user equipment when the event detector detects a no-cell-change event other than a cell-change event that indicates a change in the cell identifier.
    Type: Application
    Filed: June 10, 2014
    Publication date: June 16, 2016
    Applicant: NTT DOCOMO, INC.
    Inventors: Yasufumi Morioka, Kouki Hayashi, Masanori Ishida, Yoshifumi Morihiro
  • Publication number: 20160157052
    Abstract: A user apparatus includes processing modules that execute processing using basic area information, and an area information supply module that supplies basic area information to the processing modules. The area information supply module includes an event detection unit that detects an event, an area information acquisition unit that acquires basic area information in accordance with an event being detected, and an area information notification unit that notifies the processing modules of the basic area information. The area information acquisition unit acquires detailed area information in accordance with a request signal being received. The area information notification unit notifies a processing module of the detailed area information.
    Type: Application
    Filed: June 10, 2014
    Publication date: June 2, 2016
    Applicant: NTT DOCOMO, INC.
    Inventors: Yasufumi Morioka, Kouki Hayashi, Massanori Ishida, Yoshifumi Morihiro
  • Publication number: 20160142870
    Abstract: A radio communication system has a base station that forms a cell identified by a cell identifier, a geographic information storage unit that stores a geographic information element indicating a geographic characteristic of a location at which a cell is formed, a cell visit detector that detects that a user equipment that was visiting a first cell and starts to visit a second cell differing from the first cell, a cell information obtainer that obtains a second cell identifier corresponding to the second cell when the cell visit detector detects the visit to the second cell, and a geographic information identifier that retrieves, based on the second cell identifier, a geographic information element of the second cell that corresponds to the second cell identifier from the geographic information storage unit.
    Type: Application
    Filed: May 1, 2014
    Publication date: May 19, 2016
    Applicant: NTT DOCOMO, INC.
    Inventors: Yasufumi Morioka, Kouki Hayashi, Yoshifumi Morihiro
  • Publication number: 20160127974
    Abstract: A radio communication system includes: a visit information storage unit that stores plural visit information elements each indicating information on a visit to a cell visited by a user equipment; a cell visit detector that detects that the user equipment that was visiting a first cell starts a visit to a second cell differing from the first cell; a ping-ponging state determiner that determines whether a ping-ponging state has occurred, in which state start and ending of a visit to the second cell is repeated, wherein the determination is made based on a visit information element on a visit to the second cell visited by the user equipment; and a calculator that calculates a visit time length of the visit to the second cell in accordance with the determination by the ping-ponging state determiner.
    Type: Application
    Filed: May 1, 2014
    Publication date: May 5, 2016
    Applicant: NTT DOCOMO, INC.
    Inventors: Yasufumi Morioka, Kouki Hayashi, Yoshifumi Morihiro