Patents by Inventor Yousuke Iizuka
Yousuke Iizuka 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).
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Patent number: 9313712Abstract: One aspect of the present invention relates to a mobile apparatus, comprising: a first bandwidth measurement unit configured to measure radio conditions of a serving cell and a neighbor cell in a first bandwidth; a second bandwidth measurement unit configured to measure the radio conditions of the serving cell and the neighbor cell in a second bandwidth greater than the first bandwidth; a control unit configured to selectively activate the first bandwidth measurement unit and the second bandwidth measurement unit; and a cell transition unit configured to perform cell transition from the serving cell to the neighbor cell based on the radio conditions of the serving cell and the neighbor cell measured by the first bandwidth measurement unit and the second bandwidth measurement unit, wherein the control unit switches between the first bandwidth measurement unit and the second bandwidth measurement unit at a first switch frequency.Type: GrantFiled: March 30, 2012Date of Patent: April 12, 2016Assignee: NTT DOCOMO, INC.Inventors: Mototsugu Suzuki, Yousuke Iizuka
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Publication number: 20130217395Abstract: One aspect of the present invention relates to a mobile apparatus, comprising: a first bandwidth measurement unit configured to measure radio conditions of a serving cell and a neighbor cell in a first bandwidth; a second bandwidth measurement unit configured to measure the radio conditions of the serving cell and the neighbor cell in a second bandwidth greater than the first bandwidth; a control unit configured to selectively activate the first bandwidth measurement unit and the second bandwidth measurement unit; and a cell transition unit configured to perform cell transition from the serving cell to the neighbor cell based on the radio conditions of the serving cell and the neighbor cell measured by the first bandwidth measurement unit and the second bandwidth measurement unit, wherein the control unit switches between the first bandwidth measurement unit and the second bandwidth measurement unit at a first switch frequency.Type: ApplicationFiled: March 30, 2012Publication date: August 22, 2013Applicant: NTT DOCOMO, INC.Inventors: Mototsugu Suzuki, Yousuke Iizuka
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Patent number: 8458549Abstract: A data transmission method according to the present invention includes the steps of: (A) adding a first CRC code to transmission data; (B) dividing the transmission data to which the first CRC code has been added into a plurality of encoded bit sequences; (C) adding a second CRC code to at least one of the divided encoded bit sequences; (D) performing error correction encoding processing on the encoded bit sequences; and (E) transmitting the encoded bit sequences on which the error correction encoding processing has been performed.Type: GrantFiled: August 13, 2008Date of Patent: June 4, 2013Assignee: NTT DoCoMo, Inc.Inventors: Masayuki Furusawa, Yousuke Iizuka, Yukihiko Okumura
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Patent number: 8391172Abstract: A communication method for a radio communication system employing an enhanced uplink scheme includes the steps of determining a transmission power control bit for controlling transmission power of a downlink control channel; generating an uplink control signal including the transmission power control bit; and transmitting the uplink control signal to a base station. In the determining step, whether an indicator channel indicating acknowledgement or negative acknowledgement for an uplink data channel is receivable at a quality level better than a predetermined value is evaluated, and the transmission power control bit of the indicator channel is determined based on the evaluation result.Type: GrantFiled: April 16, 2010Date of Patent: March 5, 2013Assignee: NTT DoCoMo, Inc.Inventors: Yousuke Iizuka, Masato Maeda
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Patent number: 8295873Abstract: A disclosed communication terminal includes a determination unit analyzing a received downlink control signal and determining an allowable maximum uplink transmission power level, a measurement unit performing different frequency measurement in a transmission gap period, a threshold determination unit determining whether the allowable maximum level is higher than or equal to a threshold within a predefined period before the start and/or after the end of the transmission gap period, a transmission power control unit setting an uplink transmission power level, and a transmission unit transmitting an uplink signal at the determined power level. If the allowable maximum level is higher than or equal to the threshold, the transmission power control unit sets the uplink transmission power level to or below a predefined level lower than the allowable maximum level within the predefined period before the start and/or after the end of the transmission gap period.Type: GrantFiled: April 15, 2010Date of Patent: October 23, 2012Assignee: NTT DoCoMo, Inc.Inventors: Yousuke Iizuka, Masato Maeda
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Patent number: 8160521Abstract: Signals are received with a wider power range even through the use of existing AGCs than by conventional mobile communication terminals. In an AGC on one antenna side, in order to enable reception of a signal at a higher level, a target TA of a dynamic range DA of this AGC is changed to a value 5 dB higher than a value defined as a standard TS. On the other hand, in an AGC on another antenna side, in order to enable reception of a signal at a lower level, a target TB of a dynamic range DB of this AGC is changed to a value 5 dB lower than the value defined as the standard TS.Type: GrantFiled: January 17, 2006Date of Patent: April 17, 2012Assignee: NTT DoCoMo, Inc.Inventors: Yousuke Iizuka, Shinsuke Ogawa, Masahiro Sakai
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Patent number: 8060090Abstract: A mobile station includes a handover controller. When the mobile station simultaneously communicates with a plurality of radio base stations by using first channels and communicates only with a certain one of the plurality of radio base stations by using a second communication channel, and even when the radio quality of the certain radio base station communicating by using the second communication channel becomes deteriorated, the handover controller maintains communications with the certain radio base station communicating by using the second communication channel.Type: GrantFiled: July 20, 2007Date of Patent: November 15, 2011Assignee: NTT DoCoMo, Inc.Inventors: Hiroyuki Ishii, Yousuke Iizuka
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Patent number: 8050702Abstract: To provide a mobile station and a transmission power control method in the mobile station, which are capable of improving the power saving characteristic associated with the transmission power control in the mobile station under a condition in which the transmit diversity is applied. The transmission power of feedback information (11: FBI) is controlled on the basis of control information (TPC) transmitted through a sub-information downlink channel (21) from a base station (210) as a main branch, only when it is determined by a communication method determining section 103 that a cosed loop transmit diversity can be applied (step S201: Yes), and when it is determined by a communication base station determining section 104 that sub-information downlink channels (21, 22) and sub-information uplink channels (11, 12) are connected to a plurality of base stations (step S202: Yes).Type: GrantFiled: June 20, 2008Date of Patent: November 1, 2011Assignee: NTT DoCoMo, Inc.Inventors: Yousuke Iizuka, Yukihiko Okumura
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Patent number: 8037374Abstract: A communication terminal device and a reception environment reporting method produce a more excellent throughput, by making a report of a reception environment with higher accuracy. An SIR measuring section measures an SIR from a reception signal that has been received from a base transceiver station. A CQI converter converts the SIR that has been measured by the SIR measuring section into a CQI value. A BLER calculating section calculates a block error rate of the reception signal. A CQI correcting section corrects the CQI value that has been calculated by the CQI converter, in accordance with the block error rate. A CQI transmitter transmits the CQI value that has been corrected by the CQI correcting section, to the base transceiver station.Type: GrantFiled: April 20, 2009Date of Patent: October 11, 2011Assignee: NTT DoCoMo, Inc.Inventors: Yousuke Iizuka, Shinsuke Ogawa, Yukihiko Okumura
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Publication number: 20110214032Abstract: A data transmission method according to the present invention includes the steps of: (A) adding a first CRC code to transmission data; (B) dividing the transmission data to which the first CRC code has been added into a plurality of encoded bit sequences; (C) adding a second CRC code to at least one of the divided encoded bit sequences; (D) performing error correction encoding processing on the encoded bit sequences; and (E) transmitting the encoded bit sequences on which the error correction encoding processing has been performed.Type: ApplicationFiled: August 13, 2008Publication date: September 1, 2011Applicant: NTT DOCOMO, INC.Inventors: Masayuki Furusawa, Yousuke Iizuka, Yukihiko Okumura
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Publication number: 20110060964Abstract: A data transmission method according to the present invention includes the steps of: (A) adding a first CRC code to transmission data; (B) dividing the transmission data to which the first CRC code has been added into a plurality of encoded bit sequences; (C) adding a second CRC code to at least one of the divided encoded bit sequences; (D) performing error correction encoding processing on the encoded bit sequences; and (E) transmitting the encoded bit sequences on which the error correction encoding processing has been performed.Type: ApplicationFiled: August 13, 2008Publication date: March 10, 2011Applicant: NTT DOCOMO, INC.Inventors: Masayuki Furusawa, Yousuke Iizuka, Yukihiko Okumura
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Mobile communication terminal and associated methodology for reception during diversity interruption
Patent number: 7853231Abstract: When the diversity reception is cut, communications with the base station are continued. When it is judged by the judgment section of the mobile communication terminal that a predetermined disconnection requirement for disconnecting diversity reception is satisfied, the gain control section of the digital baseband circuitry 20 reduces the gain of the AGC14B contained in the RF receiver circuitry 10B constituting the disconnection target by a fixed value at fixed times. Diversity reception is cut after the level of the signal output by the AGC14B has reached zero.Type: GrantFiled: January 17, 2006Date of Patent: December 14, 2010Assignee: NTT DoCoMo, Inc.Inventors: Yousuke Iizuka, Shinsuke Ogawa, Masahiro Sakai -
Publication number: 20100271969Abstract: A communication method for a radio communication system employing an enhanced uplink scheme includes the steps of determining a transmission power control bit for controlling transmission power of a downlink control channel; generating an uplink control signal including the transmission power control bit; and transmitting the uplink control signal to a base station. In the determining step, whether an indicator channel indicating acknowledgement or negative acknowledgement for an uplink data channel is receivable at a quality level better than a predetermined value is evaluated, and the transmission power control bit of the indicator channel is determined based on the evaluation result.Type: ApplicationFiled: April 16, 2010Publication date: October 28, 2010Applicant: NTT DoCoMo, Inc.Inventors: Yousuke IIZUKA, Masato Maeda
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Publication number: 20100267413Abstract: A disclosed communication terminal includes a determination unit analyzing a received downlink control signal and determining an allowable maximum uplink transmission power level, a measurement unit performing different frequency measurement in a transmission gap period, a threshold determination unit determining whether the allowable maximum level is higher than or equal to a threshold within a predefined period before the start and/or after the end of the transmission gap period, a transmission power control unit setting an uplink transmission power level, and a transmission unit transmitting an uplink signal at the determined power level. If the allowable maximum level is higher than or equal to the threshold, the transmission power control unit sets the uplink transmission power level to or below a predefined level lower than the allowable maximum level within the predefined period before the start and/or after the end of the transmission gap period.Type: ApplicationFiled: April 15, 2010Publication date: October 21, 2010Applicant: NTT DoCoMo, Inc.Inventors: Yousuke Iizuka, Masato Maeda
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Patent number: 7817710Abstract: There is disclosed a mobile communication terminal equipped with a multipath interference canceller for canceling multipath interference, comprising number-of-samples controlling unit for controlling a number of samples to be sampled from a received signal, channel matrix generating unit for generating a channel matrix on the basis of sample data of samples as many as the number controlled by the number-of-samples controlling means and, interference canceling emit for canceling multipath interference on the basis of the channel matrix generated by the channel matrix generating unit.Type: GrantFiled: August 7, 2006Date of Patent: October 19, 2010Assignee: NTT DoCoMo, Inc.Inventors: Takeshi Nakamori, Hiroyuki Ishii, Yousuke Iizuka
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Mobile communication terminal and associated methodology for reception during diversity interruption
Patent number: 7751789Abstract: When the diversity reception is cut, communications with the base station are continued. When it is judged by the judgment section of the mobile communication terminal that a predetermined disconnection requirement for disconnecting diversity reception is satisfied, the gain control section of the digital baseband circuitry 20 reduces the gain of the AGC14B contained in the RF receiver circuitry 10B constituting the disconnection target by a fixed value at fixed times. Diversity reception is cut after the level of the signal output by the AGC14B has reached zero.Type: GrantFiled: January 17, 2006Date of Patent: July 6, 2010Assignee: NTT DoCoMo, Inc.Inventors: Yousuke Iizuka, Shinsuke Ogawa, Masahiro Sakai -
Patent number: 7706491Abstract: The packet reception section of the cellular phone receives a packet transmitted from the base station and the transmission error detection section detects a transmission error of the received packet. When the transmission error is detected, the retransmission request transmission section transmits a retransmission request to request the retransmission of the packet in which the transmission error is detected, to the base station, and the sample timing control section shifts the sample timing of the A/D converter by a half clock.Type: GrantFiled: March 9, 2006Date of Patent: April 27, 2010Assignee: NTT DoCoMo, Inc.Inventors: Takeshi Nakamori, Shinsuke Ogawa, Yousuke Iizuka
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Publication number: 20090287970Abstract: A communication terminal device and a reception environment reporting method produce a more excellent throughput, by making a report of a reception environment with higher accuracy. An SIR measuring section measures an SIR from a reception signal that has been received from a base transceiver station. A CQI converter converts the SIR that has been measured by the SIR measuring section into a CQI value. A BLER calculating section calculates a block error rate of the reception signal. A CQI correcting section corrects the CQI value that has been calculated by the CQI converter, in accordance with the block error rate. A CQI transmitter transmits the CQI value that has been corrected by the CQI correcting section, to the base transceiver station.Type: ApplicationFiled: April 20, 2009Publication date: November 19, 2009Applicant: NTT DoCoMo, Inc.Inventors: Yousuke IIZUKA, Shinsuke OGAWA, Yukihiko OKUMURA
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Patent number: 7602871Abstract: Improve efficiency of sampling of an A/D converter while suppressing power consumption. A packet receiving section receives six packets included in one frame transmitted from a base station, a sample timing control section shifts sample timing of the A/D converter by a half clock between former three packets and latter three packets out of six packets included in one frame.Type: GrantFiled: March 10, 2006Date of Patent: October 13, 2009Assignee: NTT DoCoMo, Inc.Inventors: Takeshi Nakamori, Shinsuke Ogawa, Yousuke Iizuka
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Publication number: 20090054025Abstract: Signals are received with a wider power range even through the use of existing AGCs than by conventional mobile communication terminals. In an AGC on one antenna side, in order to enable reception of a signal at a higher level, a target TA of a dynamic range DA of this AGC is changed to a value 5 dB higher than a value defined as a standard TS. On the other hand, in an AGC on another antenna side, in order to enable reception of a signal at a lower level, a target TB of a dynamic range DB of this AGC is changed to a value 5 dB lower than the value defined as the standard TS.Type: ApplicationFiled: January 17, 2006Publication date: February 26, 2009Applicant: NTT DoCoMo, Inc.Inventors: Yousuke Iizuka, Shinsuke Ogawa, Masahiro Sakai