Patents by Inventor Olga Mary Mracek Mitchell

Olga Mary Mracek Mitchell 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).

  • Speech processor using controlled center clipping
    Patent number: RE28919
    Abstract: An echo suppressor for full duplex telephone circuits consists of a filter bank of contiguous band filters in the transmission path, with each filter output feeding a separate center clipper. Each clipping level is controlled by echo signal amplitude as attenuated by the trans-hybrid loss that occurs in the corresponding subband. The scheme permits "double-talking" while suppressing the echo component.
    Type: Grant
    Filed: October 11, 1974
    Date of Patent: July 27, 1976
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: David Arthur Berkley, Olga Mary Mracek Mitchell, John Robinson Pierce