Patents by Inventor Mikio Iwamura

Mikio Iwamura 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: 8867470
    Abstract: A mobile communication method according to the present invention comprises: a step A of individually notifying, by a radio base station eNB, a mobile station UE performing CA of correspondence relation between a DL carrier for transmitting an “UL grant” and an UL carrier to which a PUSCH resource is assigned by the “UL grant”, and a step B of transmitting, by the mobile station UE, an uplink data signal using the PUSCH resource through the UL carrier based on the above-described correspondence relation when the “UL grant” is received through the DL carrier.
    Type: Grant
    Filed: February 15, 2011
    Date of Patent: October 21, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Anil Umesh, Mikio Iwamura, Nobuhiko Miki, Yoshihisa Kishiyama
  • Patent number: 8855043
    Abstract: A relay node of a communication system includes a communication unit that initiates a session by executing an initial connection procedure for retrieving a cell list indicating one or more donor base station candidates from a maintenance node after establishment of an initial communication link among the relay node, a base station, and a switching center, and for establishing a communication link to a donor base station in the cell list and a switching center connected to the donor base station; a storing unit that stores the cell list; and a reconnection control unit that selects, when a radio link with the donor base station is lost, a donor base station satisfying a predetermined criterion in the cell list, and that causes the communication unit to establish a communication link to the selected donor base station and a switching center connected to the selected donor base station.
    Type: Grant
    Filed: October 31, 2011
    Date of Patent: October 7, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Yasufumi Morioka, Akira Yamada, Hideaki Takahashi, Mikio Iwamura, Junichiro Hagiwara
  • Patent number: 8855646
    Abstract: User equipment 100n comprises a connection state processing section configured so that the connection state processing section measures the communication quality in a cell belonging to two or more layers, reports the result of the measurement to a base station device 200, and performs handover processing according to the instruction from the base station device 200 on the basis of first priority notified by a first control signal notified from the base station device 200 in an RRC_Connected state and a stand-by state processing section configured so that the stand-by state processing section measures the communication quality in the cell belonging to the two or more layers to determine a cell for performing a stand-by according to the result of the measurement on the basis of second priority notified by a second control signal notified from the base station device 200 in an Idle state.
    Type: Grant
    Filed: March 19, 2009
    Date of Patent: October 7, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hiroyuki Ishii, Mikio Iwamura, Takeshi Nakamori
  • Patent number: 8848663
    Abstract: A radio base station including a mobile communication system, a first relay node and a second relay node which are connected via a radio bearer, the second relay node and a radio base station which are connected via a radio bearer, where a mobile station is configured to perform a handover process between a first state, in which a radio bearer is set with the first relay node in order to communicate via the first relay node, the second relay node, and the radio base station, and a second state, in which a radio bearer is set with the radio base station in order to communicate via the radio base station, and a mobile station is configured such that during the handover process. Control signals involved in the handover process are sent and received via the radio bearer between the first relay node and the second relay node and via the radio bearer between the second relay node and the radio base station.
    Type: Grant
    Filed: April 23, 2010
    Date of Patent: September 30, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Wuri Andarmawanti Hapsari, Hideaki Takahashi, Anil Umesh, Mikio Iwamura, Minami Ishii
  • Patent number: 8849245
    Abstract: The present invention relates to a mobile communication method that sends and receives the signaling of an S1AP/X2AP layer on DRB established between a radio base station DeNB and a relay node RN, the mobile communication method including: a step of setting the above DBR in an attach process of the relay node RN; and a step of notifying the above DRB to the relay node RN and the radio base station DeNB in an attach process of the relay node RN.
    Type: Grant
    Filed: August 12, 2011
    Date of Patent: September 30, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hideaki Takahashi, Wuri Andarmawanti Hapsari, Anil Umesh, Mikio Iwamura
  • Patent number: 8849236
    Abstract: An emergency-information receiving method according to the present invention includes: starting, at mobile stations (UE), receiving scheduling-information-notification system information at a current modification period without waiting until a next modification period starts, when detecting a predetermined trigger; and receiving, at the mobile stations (UE), emergency-information-notification system information on the basis of scheduling information notified by the received scheduling-information-notification system information.
    Type: Grant
    Filed: April 24, 2009
    Date of Patent: September 30, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hiroaki Yamagishi, Mikio Iwamura
  • Patent number: 8837495
    Abstract: A mobile communication system according to the present invention comprising a plurality of Un radio bearers set between the plurality of mobile stations UE and the relay node RN, each of Un radio bearers for a predetermined QoS set for different mobile stations UE is configured to be mapped to a Un radio bearer for the predetermined QoS set between the relay node RN and the radio base station DeNB.
    Type: Grant
    Filed: June 8, 2010
    Date of Patent: September 16, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hideaki Takahashi, Wuri Andarmawanti Hapsari, Anil Umesh, Mikio Iwamura, Minami Ishii
  • Patent number: 8830928
    Abstract: A mobile communication method according to the present invention includes the steps of: (A) notifying, from a first radio base station (MBS) to a second radio base station (FBS), scheduling information including information specifying a radio resource for a control channel through which a first mobile station (MUE) that is in communication in a first cell under the control of the first radio base station (MBS) transmits downlink control information or uplink control information, when the first radio base station (MBS) assigns the radio resource; and (B) assigning, at the second radio base station (FBS), a radio resource for a control channel through which a second mobile station that is in communication in a second cell under the control of the second radio base station (FBS) transmits downlink control information or uplink control information based on the scheduling information.
    Type: Grant
    Filed: January 26, 2010
    Date of Patent: September 9, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Mikio Iwamura, Ivan Cosovic
  • Patent number: 8830901
    Abstract: A radio base station includes a mobile communication system, a relay node and a radio base station connected via a radio bearer. A mobile station is configured to conduct a handover process between the state in which a radio bearer is set with the relay node in order to communicate via the relay node and the radio base station, and the state in which a radio bearer is set with the radio base station in order to communicate via the radio base station. The mobile station is configured such that during the handover process, control signals involved in the handover process are sent and received via a radio bearer between the relay node and the radio base station.
    Type: Grant
    Filed: April 21, 2010
    Date of Patent: September 9, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Wuri Andarmawanti Hapsari, Anil Umesh, Hideaki Takahashi, Mikio Iwamura, Minami Ishii
  • Publication number: 20140248914
    Abstract: A base station determines a restriction rate for each of plural kinds of restrictions; by using a timing at which a user device in idle mode wakes up in a discontinuous reception cycle, groups the user device into one of a total number of groups and determine a timing for transmitting a paging signal for each of the groups; determines a restriction group number that is less than a sum of all restriction-rate-corresponding group numbers where one of the restriction-rate-corresponding group numbers corresponds to the restriction rate of one of the plural kinds of restrictions, determines the restriction group number of groups as restriction target groups, and changes a group corresponding to the restriction-target groups in each of predefined periods; and transmits the paging signal to the user device that belongs to one of the restriction-target groups, and transmits system information indicating that the plural kinds of restrictions are applied.
    Type: Application
    Filed: July 23, 2012
    Publication date: September 4, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Kenichiro Aoyagi, Mikio Iwamura, Kazunori Obata, Tadashi Uchiyama
  • Patent number: 8824969
    Abstract: A radio base station eNB according to the present invention includes a CA controller unit 12 configured to determine a PCC and SCCs to be used for CA communications, and a receiver unit 11 configured to receive “Measurement Report” from a mobile station UE having detected a cell having a higher radio quality in a certain SCC than a predetermined threshold for a period of TTT or longer, the “Measurement Report” containing the radio quality of the detected cell. If the cell having the highest radio quality in a measurement object CC is not under the control of the radio station eNB, the CA controller unit 12 avoids use of the cell having the highest radio quality for SCC communications in the CA communications.
    Type: Grant
    Filed: May 13, 2011
    Date of Patent: September 2, 2014
    Assignee: NTT Docomo, Inc.
    Inventors: Takeshi Nakamori, Hiroyuki Ishii, Kengo Yagyu, Mikio Iwamura
  • Patent number: 8817721
    Abstract: A mobile communication method according to the present invention includes a step A of receiving, by the mobile station UE, “UL grant” for permitting the mobile station UE to transmit an uplink data signal in UL CC#1 through PDCCH in DL CC#2, and a step B of discarding, by the mobile station UE, the “UL grant” when transmission power of the UL CC#1 is controlled on the basis of path loss estimated from DL CC#1 in a deactive state.
    Type: Grant
    Filed: April 28, 2011
    Date of Patent: August 26, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Anil Umesh, Mikio Iwamura
  • Patent number: 8811425
    Abstract: A mobile communication system according to the present invention includes: a step A in which a mobile station UE transmits an uplink data signal using a shared uplink resource designated by an uplink scheduling grant to a radio base station eNB upon reception of the uplink scheduling grant including CB-RNTI; a step B in which the radio base station eNB transmits a downlink control signal including the CB-RNTI upon successful reception of the uplink data signal transmitted by the mobile station UE; and a step C in which the radio base station eNB transmits MAC-CE including C-RNTI of the mobile station UE using a downlink resource designated by the downlink control signal.
    Type: Grant
    Filed: August 13, 2010
    Date of Patent: August 19, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Mikio Iwamura, Sadayuki Abeta
  • Patent number: 8811976
    Abstract: A mobile communication system according the present invention including a mobile station UE configured to detect a cell using CC with a measurement target frequency designated by the radio base station eNB, in a measurement gap designated by the radio base station eNB within a predetermined time period TIdentify_Inter, and when the mobile station UE is not performing CA, the predetermined time period TIdentify_Inter is determined based on the number Nfreq of the CCs with the measurement target frequencies, and when the mobile station UE is performing CA, the predetermined time period TIdentify_Inter is determined based on the number Nfreq of the CCs with the measurement target frequencies and the number M of CCs in each of which the measurement gap is set.
    Type: Grant
    Filed: February 8, 2011
    Date of Patent: August 19, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Mikio Iwamura, Hiroyuki Ishii
  • Publication number: 20140219116
    Abstract: A mobile communication method according to the present invention includes: a step in which a core network device CN transmits a predetermined notification signal to a radio base station eNB when mobile stations UE#1/UE#2 are connected to a cell under a dominant of the identical radio base station eNB; a step in which the radio base station eNB transmits a request signal to the mobile stations UE#1/UE#2 to measure radio communication quality between the mobile stations UE#1/UE#2 in response to the predetermined notification signal; a step in which the mobile stations UE#1/UE#2 transmit RS#1/RS#2 to the mobile stations UE#2/UE#1 in response to the request signal; a step in which the mobile station UE#1 transmits a measurement result of the RS#2 to the radio base station eNB; and a step in which the mobile station UE#2 transmits a measurement result of the RS#1 to the radio base station eNB.
    Type: Application
    Filed: March 27, 2012
    Publication date: August 7, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Mikio Iwamura, Hideaki Takahashi
  • Patent number: 8797956
    Abstract: A radio base station includes a mobile communication system that sends and receives control signals between a mobile station and a mobile switching center via a first radio bearer, a second radio bearer, and a wired bearer. The relay node includes a first radio bearer function, a second radio bearer function, an IP layer function, an SCTP layer function, and an application layer function. The radio base station includes a second radio bearer function, a wired bearer function, and an IP layer function. The mobile switching center includes a wired bearer function, IP layer function, SCTP layer function, and an application layer function. Keep-alive processing is performed between the SCTP layer function of the relay node and the SCTP layer function of the mobile switching center. Security processing is performed between the IP layer function of the relay node and the IP layer function of the mobile switching center.
    Type: Grant
    Filed: April 19, 2010
    Date of Patent: August 5, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Wuri Andarmawanti Hapsari, Anil Umesh, Hideaki Takahashi, Mikio Iwamura, Minami Ishii
  • Patent number: 8798667
    Abstract: A mobile communication method according to the present invention including the steps of: generating, at a mobile station (UE), first verification information by use of a first key, a first parameter and an algorithm for “Integrity Protection”; generating, at the mobile station (UE), second verification information by extracting predetermined bits of the first verification information; and performing, at the mobile station (UE), cell selection processing, and transmitting, from the mobile station to a radio base station that manages the selected cell, an RRC-PDU for RRC connection re-establishment request through a common control channel, upon detection of a radio link failure in an RRC connection, the second verification information being set in the RRC-PDU for RRC connection re-establishment request.
    Type: Grant
    Filed: June 23, 2009
    Date of Patent: August 5, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Mikio Iwamura, Wuri Andarmawanti Hapsari, Shogo Yabuki, Alf Zugenmaier
  • Patent number: 8798007
    Abstract: A radio base station according to the present invention comprising the radio base station eNB#2 comprising a transmission unit 11 configured to transmit C-RNTI that can be used in the cell #2, to the radio base station eNB #1, in response to “HO Preparation (a handover preparation signal)” received from the radio base station eNB #1 that manages the cell #1, and a resource assignment unit 14 configured to notify a radio resource assigned to the mobile station UE by using C-RNTI included in “HO Complete”, when it is determined that C-RNTI included in “HO Complete” received from the mobile station UE that can be used in the cell #2.
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: August 5, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Mikio Iwamura, Minami Ishii, Anil Umesh, Wuri Andarmawanti Hapsari
  • Patent number: 8797882
    Abstract: In a mobile station (UE) according to the present invention, a radio link failure state determination unit determines whether or not the mobile station (UE) is in a radio link failure state, based on a downlink synchronization state and a discontinuous reception state parameter, when the mobile station (UE) is in a discontinuous reception state. The radio link failure state determination unit determines whether or not the mobile station (UE) is in the radio link failure state, based on the downlink synchronization state and a non-discontinuous reception state parameter, when the mobile station (UE) is not in the discontinuous reception state.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: August 5, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hiroyuki Ishii, Mikio Iwamura
  • Publication number: 20140213218
    Abstract: A mobile communication method according to the present invention includes: a step in which a mobile management node MME generates a key Kx using a key KASME1 and a key KASME2, the key Kx being used in security of the data signal transmitted and received through a Ud interface, the key KASME1 being managed only by the mobile management node MME and a mobile station UE#1, the key KASME2 being managed only by the mobile management node MME and a mobile station UE#2; a step in which the mobile management node MME transmits the key Kx to the mobile station UE#1 and the mobile station UE#2; and a step in which the mobile station UE#1 and the mobile station UE#2 transmit and receive the data signal through the Ud interface using the key K.
    Type: Application
    Filed: March 27, 2012
    Publication date: July 31, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Mikio Iwamura, Wuri Andarmawanti Hapsari