Patents by Inventor Naoto Kawakubo

Naoto Kawakubo 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: 5420844
    Abstract: An information recording method and apparatus records information signals having data signals and synchronizing signal patterns inserted at predetermined intervals of the data signals on a recording medium with a binary level by using a coding rule without a DC free property. The synchronizing signal patterns are inserted into the data at intervals of a fixed block length and are supplied to a recording apparatus as a mark/space pattern (record signal pattern). The data are converted into the same pattern as the mark/space pattern and an accumulated value (corresponding to the average DC value) for each block length is counted. The sum and the difference of an output of a memory which stores the accumulated values from the head of the sector to the (N-1)-st block, and the accumulated value of the N-th block, are compared with each other in absolute value.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: May 30, 1995
    Assignees: Hitachi, Ltd., Hitachi Video & Information System, Inc.
    Inventors: Naoto Kawakubo, Makoto Asari, Takahiro Sunada, Noritaka Narita