Patents by Inventor Kyoji Takeyari

Kyoji Takeyari 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 multiplex transmission equipment and method
    Patent number: 5671074
    Abstract: An optical transmission system accomplishes optical transmission over a long distance by combining a multiplexing line terminal with optical amplifiers, linear repeaters, and regenerators with optical amplifiers combined together. The system also accomplishes the optical transmission over a short distance by directly connecting the linear terminals therebetween, with an electric-to-optic converter replaced by an electric-to-optic converter having a semiconductor amplifier, with an optic-to-electric converter by an optic-to-electric converter having an avalanche photodiode as light receiver, and with no use of any optical booster amplifier and optical preamplifier in the multiplexing line terminal. With these, the optical transmission system can be easily constructed depending on the transmission distance required.
    Type: Grant
    Filed: June 20, 1996
    Date of Patent: September 23, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Keiji Tomooka, Naohiro Sakakida, Shin Nishimura, Yoshihiro Ashi, Hironari Matsuda, Satoshi Aoki, Yukio Nakano, Masahiro Takatori, Toru Kazawa, Shinya Sasaki, Kyoji Takeyari, Hiroyuki Nakano