Patents by Inventor Tsutomu Washida

Tsutomu Washida 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).

  • Adaptive echo canceller
    Patent number: 4633046
    Abstract: In order to prevent tap coefficient values from drifting toward excessively large values or divergence, an adaptive echo canceller is provided with a correction signal controller which (a) reduces the tap coefficient values upon the polarities of the tap coefficient signal and the tap coefficient correction signal coinciding and (b) increases the tap coefficient values upon the polarities differing.
    Type: Grant
    Filed: February 16, 1984
    Date of Patent: December 30, 1986
    Assignees: Kokusai Denshin Denwa Co., Ltd., NEC Corporation
    Inventors: Seishi Kitayama, Tsutomu Washida, Yuzo Fukushi, Yoshinori Ito