Patents by Inventor Christopher Wayne Springfield

Christopher Wayne Springfield 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).

  • Method and system for noise suppression using external voice activity detection
    Patent number: 6618701
    Abstract: A communications transmitter which operates as a mobile telephone incorporates a noise suppressor (100, FIG. 1) which reduces the background noise in the transmitted voice signal. An external voice activity detector (150), which operates in conjunction with a noise suppressor (100) estimates the signal power of the incoming voice signal and compares this to an estimated noise floor. As a result of this comparison, a voice activity factor is applied to an updated noise floor estimate to create a voice activity threshold estimate. The voice activity threshold estimate is then used to decide whether or not to the force noise suppressor (100) to perform an update of a noise content estimate of the incoming voice signal.
    Type: Grant
    Filed: April 19, 1999
    Date of Patent: September 9, 2003
    Assignee: Motorola, Inc.
    Inventors: James Brian Piket, Ernest Pei-Ching Chen, Christopher Wayne Springfield