Patents by Inventor Ryouji Ishibashi

Ryouji Ishibashi 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).

  • Noise reducing device for up-going signals in bidirectional CATV system
    Patent number: 5317392
    Abstract: A device incorporated in a bidirectional CATV system for reducing noise introduced in an up-going channel at a subscriber station. A terminal unit and a protector perform monodirectional or bidirectional switching operations on the basis of a DC current which the terminal station selectively outputs.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: May 31, 1994
    Assignee: NEC Corporation
    Inventors: Ryouji Ishibashi, Naomasa Nishimoto
  • CATV repeating amplifier circuitry
    Patent number: 5218714
    Abstract: Bidirectional CATV (Cable Television) repeating amplifier circuitry has a first splitter, a second splitter, trunk distribution terminals used at a low level, and subscriber distribution terminals used at a high level. A distribution circuit distributes a signal from the first splitter to the distribution circuits and couples up-going signals from the distribution terminals and delivers the coupled signal to the second splitter.
    Type: Grant
    Filed: August 23, 1991
    Date of Patent: June 8, 1993
    Assignee: NEC Corporation
    Inventors: Ryouji Ishibashi, Mituo Sekiguchi