Patents by Inventor Adrian W. James

Adrian W. James 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).

  • Active noise control
    Patent number: 4876722
    Abstract: An active noise control system for reducing the amount of noise propagated along a duct comprises a microphone mounted in the wall of the duct for detecting the noise, and an active antiphase noise source, such as a loudspeaker, which is mounted substantially in the center of the cross-section of the duct. A control circuit coupled between the microphone and the antiphase noise source includes an integrator having a specific transfer function, which improves the loop gain of the microphone/source loop at low frequencies, and secures stability by altering the phase.
    Type: Grant
    Filed: May 13, 1988
    Date of Patent: October 24, 1989
    Assignee: The General Electric Company, p.l.c.
    Inventors: Nicolaas M. J. Dekker, John W. Edwards, Adrian W. James