Patents by Inventor Ronald D. McCallister

Ronald D. McCallister 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).

  • Multi-rate branch metric processor for maximum-likelihood convolutional decoder
    Patent number: 4500994
    Abstract: A branch metric processor for use in a maximum-likelihood convolutional decoder accepts a set of soft-decision symbols, an indicator of a level of quantization thereof and a set of erase control signals and generates branch metrics for base code rates of 1/3 and 1/2. The apparatus represents a substantial reduction in complexity over prior art devices. Erasure of selected symbols allows the processor to generate branch metrics for higher code rates and is advantageous in very low code rate applications.
    Type: Grant
    Filed: October 4, 1982
    Date of Patent: February 19, 1985
    Assignee: Motorola, Inc.
    Inventors: Ronald D. McCallister, James J. Crawford
  • Numerically controlled oscillator using quadrant replication and function decomposition
    Patent number: 4486846
    Abstract: A numerically controlled oscillator wherein only one quadrant of a sinusoidially shaped wave is stored in a read-only-memory and the address of the read-only-memory is generated so that the entire numerically controlled oscillator and the read-only memory are contained on a single semiconductor chip. The data required to reproduce the quadrant is stored in a decomposed format so as to reduce the size of the read-only-memory.
    Type: Grant
    Filed: June 28, 1982
    Date of Patent: December 4, 1984
    Assignee: Motorola Inc.
    Inventors: Ronald D. McCallister, Daniel Shearer, III