Patents by Inventor Katsuhiko Yamagata

Katsuhiko Yamagata 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: 8542651
    Abstract: In a communication system of a subscriber extension line system, there is provided a communication controller whereby the load of an unnecessary process to be applied on a communication controller relating to a destination of a mobile telephone is eliminated and the processing efficiency for communication control is enhanced. In a D-RNC which controls the communication of the mobile telephone and which is commonly connected with an S-RNC, the mobile telephone moves while maintaining the communication with the S-RNC. When the mobile telephone enters a cell relating to the D-RNC, the control data is transmitted or received between the S-RNC and the node for managing the mobile telephone.
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: September 24, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Masafumi Masuda, Toyohiro Abe, Takaaki Sato, Katsuhiko Yamagata
  • Patent number: 8542835
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: February 5, 2009
    Date of Patent: September 24, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Patent number: 8509784
    Abstract: A mobile communication method according to the present invention includes a step A of causing a mobile station in a standby mode in a first cell to transmit a communication start request signal, a step B of judging whether or not to measure communication quality of a second cell on the basis of judgment as to whether or not the particular service is provided in each of the cells and judgment as to whether or not communication quality of the second cell is included in the communication start request signal, the second cell overlaid by the first cell in a different frequency band and a step C of starting communication of the mobile station in either one of the first cell and the second cell on the basis of the measured communication quality of the second cell.
    Type: Grant
    Filed: November 11, 2008
    Date of Patent: August 13, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Masafumi Masuda, Yasuhiro Kawabe, Takaaki Sato, Ryoji Yamamoto, Katsuhiko Yamagata
  • Patent number: 8331935
    Abstract: When a new call occurs to or from the mobile station capable of treating a plurality of calls simultaneously, the mobile station uses the same branch structure and the same communication frequency band for all of calls. Additionally, when a new call occurs to or from the mobile station capable of treating a plurality of calls simultaneously, a branch structure and a communication frequency band, which can continue all of the calls, are selected and used.
    Type: Grant
    Filed: February 3, 2009
    Date of Patent: December 11, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Patent number: 8306535
    Abstract: A communication controller and a communication controlling method are provided, even when functionalities of the communication controller included in a communication system such as UTRAN or the like, so that the services of the functionalities are available broadly in the whole system. An RNC 102 for controlling a movable communication terminal device, in cooperation with the communication controller, receives a request for provision of a service.
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: November 6, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Masafumi Masuda, Yasuhiro Kawabe, Takaaki Sato, Katsuhiko Yamagata
  • Patent number: 8275133
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: September 25, 2012
    Assignee: NTT Docomo, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Patent number: 8259675
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: February 4, 2009
    Date of Patent: September 4, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Patent number: 8185158
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: April 9, 2009
    Date of Patent: May 22, 2012
    Assignee: NTT Mobile Communications Network, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Patent number: 7953414
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: January 28, 2009
    Date of Patent: May 31, 2011
    Assignee: NTT Docomo
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Patent number: 7907730
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: February 6, 2009
    Date of Patent: March 15, 2011
    Assignee: NTT DoCoMo, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Publication number: 20100298002
    Abstract: A mobile communication method according to the present invention includes a step A of causing a mobile station in a standby mode in a first cell to transmit a communication start request signal, a step B of judging whether or not to measure communication quality of a second cell on the basis of judgment as to whether or not the particular service is provided in each of the cells and judgment as to whether or not communication quality of the second cell is included in the communication start request signal, the second cell overlaid by the first cell in a different frequency band and a step C of starting communication of the mobile station in either one of the first cell and the second cell on the basis of the measured communication quality of the second cell.
    Type: Application
    Filed: November 11, 2008
    Publication date: November 25, 2010
    Applicant: NTT DoCoMo, Inc.
    Inventors: Masafumi Masuda, Yasuhiro Kawabe, Takaaki Sato, Ryoji Yamamoto, Katsuhiko Yamagata
  • Publication number: 20100291916
    Abstract: A communication controller and a communication controlling method are provided, even when functionalities of the communication controller included in a communication system such as UTRAN or the like, so that the services of the functionalities are available broadly in the whole system. An RNC 102 for controlling a movable communication terminal device, in cooperation with the communication controller, receives a request for provision of a service.
    Type: Application
    Filed: November 16, 2007
    Publication date: November 18, 2010
    Inventors: Masafumi Masuda, Yasuhiro Kawabe, Takaaki Sato, Katsuhiko Yamagata
  • Publication number: 20100226378
    Abstract: In a communication system of a subscriber extension line system, there is provided a communication controller whereby the load of an unnecessary process to be applied on a communication controller relating to a destination of a mobile telephone is eliminated and the processing efficiency for communication control is enhanced. In a D-RNC which controls the communication of the mobile telephone and which is commonly connected with an S-RNC, the mobile telephone moves while maintaining the communication with the S-RNC. When the mobile telephone enters a cell relating to the D-RNC, the control data is transmitted or received between the S-RNC and the node for managing the mobile telephone.
    Type: Application
    Filed: November 16, 2007
    Publication date: September 9, 2010
    Applicant: NTT DoCoMo, Inc.
    Inventors: Masafumi Masuda, Toyohiro Abe, Takaaki Sato, Katsuhiko Yamagata
  • Patent number: 7792531
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: September 7, 2010
    Assignee: NTT DoCoMo, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Patent number: 7664507
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: February 16, 2010
    Assignee: NTT DoCoMo, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Patent number: 7630716
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: December 8, 2009
    Assignee: NTT DoCoMo, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Patent number: 7577435
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Grant
    Filed: April 5, 2006
    Date of Patent: August 18, 2009
    Assignee: NTT Mobile Communications Network, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Publication number: 20090197646
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Application
    Filed: April 9, 2009
    Publication date: August 6, 2009
    Applicant: NTT Mobile Communications Network, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Publication number: 20090191924
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Application
    Filed: January 28, 2009
    Publication date: July 30, 2009
    Applicant: NTT Mobile Communications Network, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama
  • Publication number: 20090190761
    Abstract: When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover.
    Type: Application
    Filed: February 6, 2009
    Publication date: July 30, 2009
    Applicant: NTT Mobile Communications Network, Inc.
    Inventors: Motoshi Tamura, Mutsumaru Miki, Akiko Okamoto, Kenya Kusunose, Akihiro Uchikoshi, Daisuke Igarashi, Katsuhiko Yamagata, Takaaki Sato, Junichiro Hagiwara, Yasuyuki Watanabe, Takuya Hamajima, Masafumi Hata, Nobutaka Ishikawa, Yoshiyuki Yasuda, Kazufumi Yunoki, Nobuhide Uchiyama