Patents Assigned to Position Orientation Systems
  • Patent number: 4653102
    Abstract: The present invention relates to an improved directional microphone system which utilizes at least two directional microphones. The microphones included in the system are connected to an electrical circuit which is programmed to cancel static noise and to facilitate dynamic gain control. The received signals from the two microphones are fed into a microcomputer where a fast Fourier transformation is made on the two signals in order to go from the time domain to the frequency domain. A lowpass and highpass filtering technique is used to cancel the dynamic noise. The frequency components of the incoming signals are further used to utilize an area and phase sorting technique to allow only the pickup of the wanted sound in a well-defined area. An inverse fast Fourier transformation is made and the modified signal is outputted in the time domain. Sounds generated from outside the work area are essentially cancelled out by a combination of the directionality of the microphones and the sorting techniques employed.
    Type: Grant
    Filed: November 5, 1985
    Date of Patent: March 24, 1987
    Assignee: Position Orientation Systems
    Inventor: Per K. Hansen