Patents by Inventor Yuhiro Midorikawa

Yuhiro Midorikawa 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).

  • Optical OADM transmission system with loopback
    Patent number: 8351790
    Abstract: An optical transmission system including: first, second, and third stations; a main transmission path that bi-directionally couples the first station with the second station; and an optical add/drop multiplexer (OADM) disposed on the main transmission path, the OADM branching light from the first and second station, combining light from the third station to the main transmission path; wherein the OADM includes an input determination unit and an optical path switching unit, the input determination unit detects the power of the lights, and determines whether each of the input lights is lost or not, and the optical path switching unit forms a loop-back route based on the determination.
    Type: Grant
    Filed: September 28, 2010
    Date of Patent: January 8, 2013
    Assignee: Fujitsu Limited
    Inventors: Yuhiro Midorikawa, Izumi Yokota
  • OPTICAL TRANSMISSION SYSTEM
    Publication number: 20110076017
    Abstract: An optical transmission system including: first, second, and third stations; a main transmission path that bi-directionally couples the first station with the second station; and an optical add/drop multiplexer (OADM) disposed on the main transmission path, the OADM branching light from the first and second station, combining light from the third station to the main transmission path; wherein the OADM includes an input determination unit and an optical path switching unit, the input determination unit detects the power of the lights, and determines whether each of the input lights is lost or not, and the optical path switching unit forms a loop-back route based on the determination.
    Type: Application
    Filed: September 28, 2010
    Publication date: March 31, 2011
    Applicant: FUJITSU LIMITED
    Inventors: Yuhiro MIDORIKAWA, Izumi YOKOTA