Patents by Inventor Koji Kamei

Koji Kamei 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).

  • Dual-band nonreversible circuit device comprising two nonreversible circuit elements contained in a single housing to be operable in different frequency bands
    Patent number: 5898346
    Abstract: A dual-band nonreversible circuit device comprises a first circulator element (91) and a second circulator element (92) accommodated in a single housing (50, 50', 60) and operable around a first center frequency (f.sub.A) and a second center frequency (f.sub.B), respectively. The first circulator element (91) is formed by a combination of a first permanent magnet (31), a first ferrite plate (21) with a first center conductor (11), and a ground conductor plate (40) successively stacked on a lower magnetic yoke (50). Likewise, the second circulator element (92) is formed by a combination of the ground conductor plate (40), a second ferrite plate (22) with a second center conductor (12), and a second permanent magnet (32) successively stacked and covered by an upper magnetic yoke (60).
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: April 27, 1999
    Assignees: Tokin Corporation, NEC Corporation
    Inventors: Koji Kamei, Atsushi Furuta, Norihiko Ono, Shigeyoshi Yoshida, Kenji Takamoro