Patents by Inventor Ducksoo Lee

Ducksoo Lee 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 noise-shaping filter with real coefficients and method for making the same
    Patent number: 6657572
    Abstract: A digital noise-shaping filter with real coefficients for delta-sigma data converters used in a digital amplifier, 1-bit digital/analog converter, 1-bit analog/digital converter and the like, and a method for making the same. The present digital noise-shaping filter has improved noise suppression performance and system stability and reduced calculation complexity. To this end, the digital noise-shaping filter comprises a noise transfer function expressed by NTF(z)=−1+a1z−1+a2z−2+&Lgr;+aNz−N. The noise transfer function has optimum real coefficients or real coefficients approximating them.
    Type: Grant
    Filed: May 7, 2002
    Date of Patent: December 2, 2003
    Inventors: Ducksoo Lee, Yeongha Choi, Sejin Doo, Kyoungsoo Park, Koeng-Mo Sung
  • Digital noise-shaping filter with real coefficients and method for making the same
    Publication number: 20030086500
    Abstract: A digital noise-shaping filter with real coefficients for delta-sigma data converters used in a digital amplifier, 1-bit digital/analog converter, 1-bit analog/digital converter and the like, and a method for making the same. The present digital noise-shaping filter has improved noise suppression performance and system stability and reduced calculation complexity. To this end, the digital noise-shaping filter comprises a noise transfer function expressed by NTF(z)=−1+a1z−1+a2z−2+&Lgr;+aNz−N. The noise transfer function has optimum real coefficients or real coefficients approximating them.
    Type: Application
    Filed: May 7, 2002
    Publication date: May 8, 2003
    Inventors: Ducksoo Lee, Yeongha Choi, Sejin Doo, Kyoungsoo Park, Koeng-mo Sung