Patents by Inventor Ganesh Rajan

Ganesh Rajan 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).

  • Sampling rate conversion using polyphase filters with interpolation
    Patent number: 5274372
    Abstract: A sampling rate converter for converting an input digital signal, such as D2 PAL, into an output digital signal, such as D1 PAL, has a pair of polyphase filters. The input digital signal is input in parallel to the two polyphase filters, with the phase selected by one of the filters being offset by one from that of the other. The outputs of the polyphase filters are input to a linear interpolator to produce the output digital signal. The resolution of the sampling rate conversion is a function of the number of phases N of the polyphase filters and the number of interpolation steps M of the interpolator.
    Type: Grant
    Filed: October 23, 1992
    Date of Patent: December 28, 1993
    Assignees: Tektronix, Inc., The Grass Valley Group, Inc.
    Inventors: Ajay K. Luthra, Ganesh Rajan, Ronald Alspaugh
  • Coefficient reduction in a low ratio sampling rate converter
    Patent number: 5023825
    Abstract: A technique for reducing the number of coefficients in a low ratio sampling rate converter divides each input sampling rate interval into a plurality of bins. For each bin a set of conversion coefficients is computed. So long as output data samples lie within the same bin, the same set of coefficients is applied. When the output data samples move to another bin, the set of coefficients applied is changed. Thus a finite set of coefficients are computed rather than computing an exact set for each output data sample.
    Type: Grant
    Filed: August 20, 1990
    Date of Patent: June 11, 1991
    Assignee: Tektronix, Inc.
    Inventors: Ajay K. Luthra, Ganesh Rajan