Patents by Inventor Richard L. Keizer

Richard L. Keizer 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: 7724844
    Abstract: A servo system for detecting and demodulating servo data is disclosed. In illustrated aspects, a demodulation circuit or portion includes a correlator component configured to output a correlation of a sequence of equalized channel samples with a sequence of correlator weight derived based on at least one mapped channel sequence. A decision component, for example a threshold detector uses the correlation results to output a data bit symbol based upon the correlation of the sequence of equalized channel samples to the at least one mapped channel sequence.
    Type: Grant
    Filed: January 31, 2007
    Date of Patent: May 25, 2010
    Assignee: Seagate Technology LLC
    Inventors: Mehmet F. Erden, Richard L. Keizer
  • Publication number: 20080180825
    Abstract: A servo system for detecting and demodulating servo data is disclosed. In illustrated aspects, a demodulation circuit or portion includes a correlator component configured to output a correlation of a sequence of equalized channel samples with a sequence of correlator weight derived based on at least one mapped channel sequence. A decision component, for example a threshold detector uses the correlation results to output a data bit symbol based upon the correlation of the sequence of equalized channel samples to the at least one mapped channel sequence.
    Type: Application
    Filed: January 31, 2007
    Publication date: July 31, 2008
    Applicant: Seagate Technology LLC
    Inventors: Mehmet F. Erden, Richard L. Keizer
  • Patent number: 7064914
    Abstract: In a method for generating a confidence level of a position error signal (PES) component that is indicative of a quality of the PES component, a PES component is generated using position signal samples of a read back signal corresponding to a servo burst pattern. Next, a noise level corresponding to noise in the read back signal is extracted using the position signal samples. A confidence level is then generated based on the PES component and the noise level. A system for performing the method includes a transformation block, a position error signal (PES) component extractor, a noise extractor, and a confidence level generator. The transformation block is configured to receive position signal samples of a read back signal corresponding to a servo burst pattern taken at a sampling frequency. A transformed domain representation of the position signal samples is then generated by the transformation block based on the sampling frequency and the servo burst pattern.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: June 20, 2006
    Assignee: Seagate Technology LLC
    Inventors: Mehmet Fatih Erden, Richard L. Keizer, Alexei Hiram Sacks, Timothy Francis Ellis