Patents by Inventor Hisasi Kiyonaga

Hisasi Kiyonaga 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).

  • Remote return loop control in a data transmission system
    Patent number: 4529979
    Abstract: In a return loop control system in a data transmission system having data transmission units such as modems connected at opposite ends of a transmission line, a return loop being formed at one of the data transmission units by a command signal from the other data transmission unit when the transmission line, modulator, demodulator, etc. are to be tested. Where a data to be transmitted is sent out a predetermined time period later than the send-out of a signal for establishing a communication status to the transmission line, a command signal for forming a return loop is sent out within the predetermined time period.
    Type: Grant
    Filed: July 14, 1982
    Date of Patent: July 16, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Takeo Kusama, Hisasi Kiyonaga