Patents by Inventor Mitsuru Kaga

Mitsuru Kaga 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).

  • Digital modulator/demodulator including non-linear analog-to-digital converter and circuitry compensating for the non-linearity of the converter
    Patent number: 4800574
    Abstract: A low cost analog-to-digital converter having a non-linear conversion characteristic produces an output digital signal non-linearly relative to an input analog transmission signal which is applied thereto for demodulation. A compensation circuit having a non-linear conversion characteristic converts the non-linear digital signal output from the analog-to-digital converter into a linear digital signal which has a larger number of bits than the non-linear digital signal.
    Type: Grant
    Filed: May 7, 1984
    Date of Patent: January 24, 1989
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigetaka Tanaka, Toshiaki Tanigawa, Mitsuru Kaga
  • Synchronization detection system for data transmission
    Patent number: 4608703
    Abstract: A synchronization detecting system for data transmission in which a two-dimensionally modulated signal is received by way of a demodulator. In a training sequence for a two-dimensional modulation modem, a point of transition from an alternation to a pseudorandom symbol sequence is detected by producing a sum of the vectors of two signals which are remote from each other by a period of two samples, or a difference therebetween. Whether the detection of the transition point has been correct is decided utilizing the alternation.
    Type: Grant
    Filed: May 9, 1984
    Date of Patent: August 26, 1986
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuru Kaga, Shigetaka Tanaka