Patents by Inventor Sigmund A. BIRKELAND

Sigmund A. BIRKELAND 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 cancellation system for helmets
    Patent number: 11683644
    Abstract: A helmet including an active noise cancellation (ANC) system which includes a first reference microphone for measuring sound pressure at a first location on a first side of the helmet, the first location between a defined spatial region and a first source of sound and a second reference microphone for measuring sound pressure at a second location, different to the first location, on the first side. The second location is between the defined spatial region and a second source of sound. A loud speaker is provided in or adjacent to the defined spatial region. A control unit determines, based on output signals from the first and second microphones, a drive signal for driving the loudspeaker to generate a sound signal that at least partially attenuates, in the defined spatial region and in the first frequency range, the sound signals from the first and second noise sources.
    Type: Grant
    Filed: September 27, 2019
    Date of Patent: June 20, 2023
    Assignee: DAAL Noise Control Systems AS
    Inventors: Dag Axel Aarset Loe, Sigmund A. Birkeland
  • AN ACTIVE NOISE CANCELLATION SYSTEM FOR HELMETS
    Publication number: 20220007107
    Abstract: A helmet including an active noise cancellation (ANC) system which includes a first reference microphone for measuring sound pressure at a first location on a first side of the helmet, the first location between a defined spatial region and a first source of sound and a second reference microphone for measuring sound pressure at a second location, different to the first location, on the first side. The second location is between the defined spatial region and a second source of sound. A loud speaker is provided in or adjacent to the defined spatial region. A control unit determines, based on output signals from the first and second microphones, a drive signal for driving the loudspeaker to generate a sound signal that at least partially attenuates, in the defined spatial region and in the first frequency range, the sound signals from the first and second noise sources.
    Type: Application
    Filed: September 27, 2019
    Publication date: January 6, 2022
    Inventors: Dag Axel Aarset LOE, Sigmund A. BIRKELAND