Patents by Inventor Hiroyuki Nisikawa

Hiroyuki Nisikawa 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).

  • Patent number: 5978651
    Abstract: In a video signal transmission method and system wherein a signal containing a video signal is bidirectionally transmitted and received in a substantially real time in video appliances coupled via a transmission path to each other, a digital signal containing a digital video signal is time-compressed, and a transmission operation is controlled in such a manner that a transmission period and a no transmission period are alternately produced in a preselected period. Then, the time-compressed digital signal is transmitted to the transmission path during the transmission period, whereas another digital signal transmitted via the transmission path from the video appliance on the counter side is received during the no transmission period. Then, the received digital signal is time-expanded to reproduce the original signal.
    Type: Grant
    Filed: April 14, 1997
    Date of Patent: November 2, 1999
    Assignee: Hitachi Denshi Kabushiki Kaisha
    Inventors: Yoshizumi Eto, Nobuo Murata, Kazuhiro Tanabe, Hiroyuki Nisikawa
  • Patent number: 5821995
    Abstract: In a transmission system for bi-directionally transmitting and receiving a plurality of signals between two units, interconnected through a predetermined transmission path, if one of the plurality of signals falls into any of a transmission disabled state, a transmission not required state, a reception disabled state, and a reception not required state, at least one of a transmission operation and a reception operation for the signal in the one state is stopped or set into a stand-by state, thereby reducing electric power consumed by the transmission system. In addition, a transmission bandwidth of the transmission path is reduced by a portion associated with the signal in the one state, or an entire bandwidth for all signals except for the signal in the one state is expanded without changing the transmission bandwidth of the transmission path.
    Type: Grant
    Filed: April 22, 1996
    Date of Patent: October 13, 1998
    Assignee: Hitachi Denshi Kabushiki Kaisha
    Inventor: Hiroyuki Nisikawa
  • Patent number: 5701581
    Abstract: In a video signal transmission method and system wherein a signal containing a video signal is bidirectionally transmitted and received in a substantially real time in video appliances coupled via a transmission path to each other, a digital signal containing a digital video signal is time-compressed, and a transmission operation is controlled in such a manner that a transmission period and a no transmission period are alternately produced in a preselected period. Then, the time-compressed digital signal is transmitted to the transmission path during the transmission period, whereas another digital signal transmitted via the transmission path from the video appliance on the counter side is received during the no transmission period. Then, the received digital signal is time-expanded to reproduce the original signal.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: December 23, 1997
    Assignee: Hitachi Denshi Kabushiki Kaisha
    Inventors: Yoshizumi Eto, Nobuo Murata, Kazuhiro Tanabe, Hiroyuki Nisikawa