Patents by Inventor Takahiro Iyama

Takahiro Iyama 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: 9144030
    Abstract: A mobile communication terminal includes: a transmission power controlling unit for performing transmission power control such that the sum of channel transmission powers or the sum of the ratios of the channel transmission powers to threshold values of the corresponding channels is a predetermined target value; an average transmission power calculating unit for calculating the average value of the sum of the channel transmission powers in a set monitoring period or the average value of the sum of the ratios of the channel transmission powers in the set monitoring period to the threshold values of the corresponding channels; and a transmission power suppressing unit for performing reduction control of the transmission powers such that these average values in a set control period are each equal to or less than the threshold value.
    Type: Grant
    Filed: April 18, 2011
    Date of Patent: September 22, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Takahiro Iyama, Teruo Onishi
  • Patent number: 8903666
    Abstract: An object of the present invention is to provide a simple way of measuring the local average absorbed power of a radio device having a plurality of antennas. A local average absorbed power measuring method of the present invention has an individual measurement step and a calculation step. In the calculation step, local average absorbed power candidates are obtained while weights are being varied. In a local average absorbed power candidate calculation sub-step, the absorbed power distribution in three-dimensional space is calculated from the combined electric field or combined magnetic field obtained in the combination sub-step, and a local average absorbed power candidate is obtained. In a local average absorbed power selection step, the highest one of the local average absorbed power candidates is specified.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: December 2, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Takahiro Iyama, Teruo Onishi
  • Publication number: 20130077522
    Abstract: A mobile communication terminal includes: a transmission power controlling unit for performing transmission power control such that the sum of channel transmission powers or the sum of the ratios of the channel transmission powers to threshold values of the corresponding channels is a predetermined target value; an average transmission power calculating unit for calculating the average value of the sum of the channel transmission powers in a set monitoring period or the average value of the sum of the ratios of the channel transmission powers in the set monitoring period to the threshold values of the corresponding channels; and a transmission power suppressing unit for performing reduction control of the transmission powers such that these average values in a set control period are each equal to or less than the threshold value.
    Type: Application
    Filed: April 18, 2011
    Publication date: March 28, 2013
    Applicant: NTT DOCOMO, INC.
    Inventors: Takahiro Iyama, Teruo Onishi
  • Publication number: 20110301886
    Abstract: An object of the present invention is to provide a simple way of measuring the local average absorbed power of a radio device having a plurality of antennas. A local average absorbed power measuring method of the present invention has an individual measurement step and a calculation step. In the individual measurement step, the amplitude and phase of the electric field or magnetic field of each one of the plurality of antennas are measured. In the calculation step, local average absorbed power candidates are obtained while weights are being varied. More specifically, in a combination sub-step, given weights are applied to the amplitudes and phases of the electric fields or magnetic fields of the individual antennas, obtained in the individual measurement step, and the results are combined.
    Type: Application
    Filed: January 29, 2010
    Publication date: December 8, 2011
    Applicant: NTT DOCOMO, INC.
    Inventors: Takahiro Iyama, Teruo Onishi
  • Patent number: 7683632
    Abstract: A disclosed specific absorption rate measurement system according to an embodiment of the present invention measures a specific absorption rate of electromagnetic waves from a radiating source absorbed in a dielectric medium. The system includes a measurement portion that measures a first electric field vector on an observation surface which is a two-dimensional surface in the dielectric medium; an electric field calculation portion that calculates a second electric field vector in a point excluded from the observation surface in accordance with electric field components of the first electric field vector measured on the observation surface, the electric field components being parallel to the observation surface; and a calculation portion that calculates the specific absorption rate from the calculated second electric field vector.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: March 23, 2010
    Assignee: NTT DoCoMo, Inc.
    Inventors: Katsuki Kiminami, Takahiro Iyama, Teruo Onishi
  • Patent number: 7615188
    Abstract: In an apparatus for measuring absorbed power including an electromagnetic field probe 1 fixedly mounted within a head simulation phantom 2 which simulates the configuration and the electromagnetic characteristics of a head of a human body, and wherein the strength of an electric field or a magnetic field of a radio wave externally irradiated upon the head simulation phantom 2 is measured by the electromagnetic field probe 1, and the power of the radio wave absorbed by the head is estimated on the basis of measured values, the head simulation phantom 2 comprises a solid dielectric 10? which simulates the configuration and the electromagnetic characteristics of a head of a human body or a liquid dielectric 10 which simulates the electromagnetic characteristics of a head of a human body and which is filled in an enclosed vessel 10 which simulates the configuration of a head of a human body. The volume of the solid dielectric 10? or the volume of the enclosed vessel 11 is equal to or less than 5×105 mm3.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: November 10, 2009
    Assignee: NTT DoCoMo, Inc.
    Inventors: Takahiro Iyama, Yoshiaki Tarusawa, Shinji Uebayashi, Toshio Nojima
  • Publication number: 20080265902
    Abstract: A disclosed specific absorption rate measurement system according to an embodiment of the present invention measures a specific absorption rate of electromagnetic waves from a radiating source absorbed in a dielectric medium. The system includes a measurement portion that measures a first electric field vector on an observation surface which is a two-dimensional surface in the dielectric medium; an electric field calculation portion that calculates a second electric field vector in a point excluded from the observation surface in accordance with electric field components of the first electric field vector measured on the observation surface, the electric field components being parallel to the observation surface; and a calculation portion that calculates the specific absorption rate from the calculated second electric field vector.
    Type: Application
    Filed: October 17, 2007
    Publication date: October 30, 2008
    Applicant: NTT DoCoMo, Inc.
    Inventors: Katsuki KIMINAMI, Takahiro Iyama, Teruo Onishi
  • Patent number: 7186377
    Abstract: In an apparatus for measuring absorbed power including an electromagnetic field probe 1 fixedly mounted within a head simulation phantom 2 which simulates the configuration and the electromagnetic characteristics of a head of a human body, and wherein the strength of an electric field or a magnetic field of a radio wave externally irradiated upon the head simulation phantom 2 is measured by the electromagnetic field probe 1, and the power of the radio wave absorbed by the head is estimated on the basis of measured values, the head simulation phantom 2 comprises a solid dielectric 10? which simulates the configuration and the electromagnetic characteristics of a head of a human body or a liquid dielectric 10 which simulates the electromagnetic characteristics of a head of a human body and which is filled in an enclosed vessel 10 which simulates the configuration of a head of a human body. The volume of the solid dielectric 10? or the volume of the enclosed vessel 11 is equal to or less than 5×105 mm3.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: March 6, 2007
    Assignee: NTT DoCoMo, Inc.
    Inventors: Takahiro Iyama, Yoshiaki Tarusawa, Shinji Uebayashi, Toshio Nojima
  • Publication number: 20060172432
    Abstract: In an apparatus for measuring absorbed power including an electromagnetic field probe 1 fixedly mounted within a head simulation phantom 2 which simulates the configuration and the electromagnetic characteristics of a head of a human body, and wherein the strength of an electric field or a magnetic field of a radio wave externally irradiated upon the head simulation phantom 2 is measured by the electromagnetic field probe 1, and the power of the radio wave absorbed by the head is estimated on the basis of measured values, the head simulation phantom 2 comprises a solid dielectric 10? which simulates the configuration and the electromagnetic characteristics of a head of a human body or a liquid dielectric 10 which simulates the electromagnetic characteristics of a head of a human body and which is filled in an enclosed vessel 10 which simulates the configuration of a head of a human body. The volume of the solid dielectric 10? or the volume of the enclosed vessel 11 is equal to or less than 5×105 mm3.
    Type: Application
    Filed: March 30, 2006
    Publication date: August 3, 2006
    Applicant: NTT DoCoMo, Inc
    Inventors: Takahiro Iyama, Yoshiaki Tarusawa, Shinji Uebayashi, Toshio Nojima
  • Publication number: 20040102694
    Abstract: In an apparatus for measuring absorbed power including an electromagnetic field probe 1 fixedly mounted within a head simulation phantom 2 which simulates the configuration and the electromagnetic characteristics of a head of a human body, and wherein the strength of an electric field or a magnetic field of a radio wave externally irradiated upon the head simulation phantom 2 is measured by the electromagnetic field probe 1, and the power of the radio wave absorbed by the head is estimated on the basis of measured values, the head simulation phantom 2 comprises a solid dielectric 10′ which simulates the configuration and the electromagnetic characteristics of a head of a human body or a liquid dielectric 10 which simulates the electromagnetic characteristics of a head of a human body and which is filled in an enclosed vessel 10 which simulates the configuration of a head of a human body.
    Type: Application
    Filed: April 7, 2003
    Publication date: May 27, 2004
    Inventors: Takahiro Iyama, Yoshiaki Tarusawa, Shinji Uebayashi, Toshio Nojima