Patents by Inventor Junichi Akahani

Junichi Akahani 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 wavelength division multiplexing transmission network system using transmitting/receiving apparatuses having 2-input and 2-output optical path switching elements
    Patent number: 6643463
    Abstract: An optical wavelength division multiplexing transmission network system having a star-topology network is disclosed, which comprises an arrayed-waveguide grating type multiplexing/demultiplexing circuit having N input ports and N output ports, and N transmitting/receiving apparatuses, each apparatus including a transmitter, receiver, demultiplexer, multiplexer, and N 2-input and 2-output optical path switching elements corresponding to N wavelengths, so as to cope with a damage to a transmitting or receiving portion corresponding to a specific wavelength. Each switching element is independently switched between first and second connective conditions.
    Type: Grant
    Filed: June 21, 2000
    Date of Patent: November 4, 2003
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Senichi Suzuki, Masao Kawachi, Kennosuke Fukami, Yuji Akatsu, Kazutosi Kato, Mitsuru Harada, Junichi Akahani, Atsushi Takahara