Patents by Inventor Robert Winston Nowlin

Robert Winston Nowlin 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: 7570937
    Abstract: Comfort noise is derived from a white noise signal by filtering the white noise signal in a QMF bank to produce comfort noise signal that is selectively coupled to at least one channel in a telephone. Preferably, a plurality of QMF banks are used and the magnitude of the white noise into each filter is controlled in accordance with the magnitude of the signal in a corresponding analysis sub-band in a channel. In accordance with another aspect of the invention, the signals from higher frequency analysis sub-bands are combined and control a single input to a QMF bank, thereby increasing the low frequency resolution of the comfort noise. In accordance with another aspect of the invention, the QMF banks are cascaded upwardly (the output of one bank is coupled to the low pass input of the next bank), which also enhances the low frequency resolution of the comfort noise.
    Type: Grant
    Filed: August 21, 2003
    Date of Patent: August 4, 2009
    Assignee: Acoustic Technologies, Inc.
    Inventors: Robert Winston Nowlin, Seth Suppappola