Patents by Inventor Tetsushi Nakano

Tetsushi Nakano 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).

  • Publication number: 20040197100
    Abstract: The objective is an optical transmission unit capable of coupling and branching signal lights of individual wavelengths at a data rate of 10 Gbits/s. In order to achieve the objective, DCFs are provided and proper values of dispersion compensation are given, so that different characteristics depending on the respective wavelengths to be coupled, split and pass through without being split are obtained. The signal lights are amplified by a plurality of low-excitation optical amplifiers to regain their light levels which are weakened due to using an optical coupler, branching filter and DCF together, thereby enabling a long-distance transmission.
    Type: Application
    Filed: March 25, 2004
    Publication date: October 7, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Tadashi Matsuoka, Junya Kosaka, Tetsushi Nakano
  • Patent number: 6771854
    Abstract: The objective is an optical transmission unit capable of coupling and branching signal lights of individual wavelengths at a data rate of 10 Gbits/s. In order to achieve the objective, DCFs are provided and proper values of dispersion compensation are given, so that different characteristics depending on the respective wavelengths to be coupled, split and pass through without being split are obtained. The signal lights are amplified by a plurality of low-excitation optical amplifiers to regain their light levels which are weakened due to using an optical coupler, branching filter and DCF together, thereby enabling a long-distance transmission.
    Type: Grant
    Filed: April 28, 2003
    Date of Patent: August 3, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Tadashi Matsuoka, Junya Kosaka, Tetsushi Nakano
  • Publication number: 20030206692
    Abstract: The objective is an optical transmission unit capable of coupling and branching signal lights of individual wavelengths at a data rate of 10 Gbits/s. In order to achieve the objective, DCFs are provided and proper values of dispersion compensation are given, so that different characteristics depending on the respective wavelengths to be coupled, split and pass through without being split are obtained. The signal lights are amplified by a plurality of low-excitation optical amplifiers to regain their light levels which are weakened due to using an optical coupler, branching filter and DCF together, thereby enabling a long-distance transmission.
    Type: Application
    Filed: April 28, 2003
    Publication date: November 6, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Tadashi Matsuoka, Junya Kosaka, Tetsushi Nakano
  • Patent number: 6563978
    Abstract: The objective is an optical transmission unit capable of coupling and branching signal lights of individual wavelengths at a data rate of 10 Gbits/s. In order to achieve the objective, DCFs are provided and proper values of dispersion compensation are given, so that different characteristics depending on the respective wavelengths to be coupled, split and pass through without being split are obtained. The signal lights are amplified by a plurality of low-excitation optical amplifiers to regain their light levels which are weakened due to using an optical coupler, branching filter and DCF together, thereby enabling a long-distance transmission.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: May 13, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Tadashi Matsuoka, Junya Kosaka, Tetsushi Nakano
  • Publication number: 20010024544
    Abstract: The objective is an optical transmission unit capable of coupling and branching signal lights of individual wavelengths at a data rate of 10 Gbits/s. In order to achieve the objective, DCFs are provided and proper values of dispersion compensation are given, so that different characteristics depending on the respective wavelengths to be coupled, split and pass through without being split are obtained. The signal lights are amplified by a plurality of low-excitation optical amplifiers to regain their light levels which are weakened due to using an optical coupler, branching filter and DCF together, thereby enabling a long-distance transmission.
    Type: Application
    Filed: March 19, 2001
    Publication date: September 27, 2001
    Inventors: Tadashi Matsuoka, Junya Kosaka, Tetsushi Nakano
  • Patent number: 5740158
    Abstract: An ATM communication system including a plurality of communication nodes connected in a loop form by buses, buffers disposed in each communication node, a synchronizing pulse generation circuit for conducting cell demultiplexing of all communication nodes at the same timing, storage devices disposed in each communication node to store mounting position information of the communication node and slot generator position information, and a circuit used by each communication node to automatically transmit and receive cells on the basis of position information described above.
    Type: Grant
    Filed: October 10, 1996
    Date of Patent: April 14, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Kaoru Aoki, Masataka Takano, Junichirou Yanagi, Tetsushi Nakano, Miho Iino
  • Patent number: 5604729
    Abstract: An ATM communication system including a plurality of communication nodes connected in a loop form by buses, buffers disposed in each communication node, a synchronizing pulse generation circuit for conducting cell demultiplexing of all communication nodes at the same timing, storage devices disposed in each communication node to store mounting position information of the communication node and slot generator position information, and a circuit used by each communication node to automatically transmit and receive cells on the basis of position information described above.
    Type: Grant
    Filed: September 29, 1994
    Date of Patent: February 18, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Kaoru Aoki, Masataka Takano, Junichirou Yanagi, Tetsushi Nakano, Miho Iino