Patents by Inventor Thomas W. Holden

Thomas W. Holden 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: 5297213
    Abstract: A noise reduction system for removing unwanted audio noise during a pause. The system receives an intelligence plus noise signal that is split and fed to a first rectifier having a first polarity, and through a filter to a second rectifier having a polarity opposite to the first rectifier. The filter removes components below a frequency where most energy-frequency is distributed in human speech. The output of the rectifiers is summed to produce an output signal when most audio noise between pauses in voice is reduced.
    Type: Grant
    Filed: April 6, 1992
    Date of Patent: March 22, 1994
    Inventor: Thomas W. Holden
  • Patent number: 4703507
    Abstract: A noise reduction system and method for reducing noise occurring during pauses in information bearing audio signals has an audio input connected to one input of a differential output circuit. A variable gain circuit has an input connected to the audio input and an output connected to the other input of the differential circuit. A dc control signal is derived from the incoming signals and controls the variable gain circuit to cause cancellation of a noise only signal during periods of no information bearing audio signals.
    Type: Grant
    Filed: July 25, 1986
    Date of Patent: October 27, 1987
    Inventor: Thomas W. Holden
  • Patent number: 3973210
    Abstract: A selective wave filter that employs a frequency selective circuit that provides a waveform that represents the envelope of an input tone burst, such as a dot or dash used in radio telegraphy. The output of the frequency selective circuit is connected to a rectifier and the output of the rectifier is connected to a filter that removes most of the audio components and allows the resultant pulse to pass to an output circuit. The output circuit employs apparatus in the form of a balanced modulator, voltage controlled amplifier or the like.
    Type: Grant
    Filed: January 14, 1975
    Date of Patent: August 3, 1976
    Inventor: Thomas W. Holden