Patents by Inventor Katsutoshi USAMI

Katsutoshi USAMI 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: 10020887
    Abstract: A wireless communication system includes a baseband processing device configured to transmit a data signal via an optical transmission line, and a wireless device configured to receive the data signal via the optical transmission line and carry out wireless transmission of an output signal obtained by amplifying the data signal, wherein the wireless device is configured to amplify the data signal to generate the output signal, generate a feedback signal according to the output signal, and transmit the feedback signal to the baseband processing device via the optical transmission line, and wherein the baseband processing device is configured to acquire the feedback signal from the wireless device, and execute first processing of multiplying the data signal by a distortion compensation coefficient corresponding to an inverse characteristic of distortion in the radio frequency circuit based on the feedback signal.
    Type: Grant
    Filed: January 27, 2017
    Date of Patent: July 10, 2018
    Assignee: FUJITSU LIMITED
    Inventors: Daisuke Masunaga, Akira Toyomane, Katsutoshi Usami, Masaaki Okada
  • Publication number: 20170141850
    Abstract: A wireless communication system includes a baseband processing device configured to transmit a data signal via an optical transmission line, and a wireless device configured to receive the data signal via the optical transmission line and carry out wireless transmission of an output signal obtained by amplifying the data signal, wherein the wireless device is configured to amplify the data signal to generate the output signal, generate a feedback signal according to the output signal, and transmit the feedback signal to the baseband processing device via the optical transmission line, and wherein the baseband processing device is configured to acquire the feedback signal from the wireless device, and execute first processing of multiplying the data signal by a distortion compensation coefficient corresponding to an inverse characteristic of distortion in the radio frequency circuit based on the feedback signal.
    Type: Application
    Filed: January 27, 2017
    Publication date: May 18, 2017
    Inventors: Daisuke MASUNAGA, Akira TOYOMANE, Katsutoshi USAMI, Masaaki OKADA
  • Publication number: 20160366650
    Abstract: A wireless communication device including: a memory, and a processor coupled to the memory and configured to: receive a first control signal and a second control signal from another wireless communication device, the first control signal being a control signal for adjusting a transmission timing of the wireless communication device, the second control signal being a control signal for adjusting a transmission power of the wireless communication device, perform a first adjustment for the transmission power of the wireless communication device based on the second control signal, start a second adjustment for the transmission power of the wireless communication device based on the first control signal, and stop the second adjustment based on a received power from the another wireless communication device.
    Type: Application
    Filed: June 2, 2016
    Publication date: December 15, 2016
    Inventors: Hiroki SATOU, Mitsuo KOBAYASHI, Toshifumi FUJIMOTO, Katsutoshi USAMI
  • Publication number: 20160112134
    Abstract: A wireless communication system includes a baseband processing device configured to transmit a data signal via an optical transmission line, and a wireless device configured to receive the data signal via the optical transmission line and carry out wireless transmission of an output signal obtained by amplifying the data signal, wherein the wireless device is configured to amplify the data signal to generate the output signal, generate a feedback signal according to the output signal, and transmit the feedback signal to the baseband processing device via the optical transmission line, and wherein the baseband processing device is configured to acquire the feedback signal from the wireless device, and execute first processing of multiplying the data signal by a distortion compensation coefficient corresponding to an inverse characteristic of distortion in the radio frequency circuit based on the feedback signal.
    Type: Application
    Filed: August 14, 2015
    Publication date: April 21, 2016
    Inventors: Daisuke MASUNAGA, Akira TOYOMANE, Katsutoshi USAMI, Masaaki OKADA