5699436 : Hands free noise canceling headset
INVENTORS: Claybaugh; David, Germantown, MD
Denenberg; Jeffrey N., Trumbull, CT
ASSIGNEES: Noise Cancellation Technologies, Inc., Linthicum, MD
ISSUED:Dec. 16, 1997 FILED: Oct. 27, 1994
SERIAL NUMBER: 325397  MAINT. STATUS:
INTL. CLASS: G10K+1116;
U.S. CLASS:381-071; 381-094;
FIELD OF SEARCH: 381-71,72,74,94,103,155 ; 181-206;
379-406,407,410,412,387,388,390,395;
AGENTS:none

ABSTRACT:  

  • In the area of active noise cancellation headsets, the noisy environment often encountered in the link with communication systems causes lack of intelligibility on the outward communications path. Consequently another in-wire cancellation channel to enhance the intelligibility is required. This additional processing channel adds to the cost of the headset. The invention uses residual microphones (12) to reproduce the sound that remains in the ear after cancellation so that the controller (13) can make further adjustments through filter (15) and LMS adapter (14) to the anti-noise signal.

    • U.S. REFERENCES:   (No patents reference this one)
    Patent No. Inventor Issued Title
    2972018 * Hawley et al.2 /1961  
    4258235 Watson3 /1981 Pressure gradient electret microphone
    4654871 Chaplin3 /1987 Method and apparatus for reducing repetitive noise entering the ear
    4677677 Eriksson6 /1987 Active sound attenuation system with on-line adaptive feedback cancellation
    4736432 Cantrell4 /1988 Electronic siren audio notch filter for transmitters
    4953217 Twiney et al.8 /1990 Noise reduction system
    4977600 Ziegler12 /1990 Sound attenuation system for personal seat
    5001763 Moseley3 /1991 Electroacoustic device for hearing needs including noise cancellation
    5033082 Eriksson et al.7 /1991 Communication system with active noise cancellation
    5046103 Warnaka9 /1991 Noise reducing system for voice microphones
    5091954 Sasaki et al.2 /1992 Noise reducing receiver device
    5105377 Ziegler4 /1992 Digital virtual earth active cancellation system
    5182774 Bourk1 /1993 Noise cancellation headset
    5402497 Nishimoto3 /1995 Headphone apparatus for reducing circumference noise
    5481615 Eatwell1 /1996 Audio reproduction system
      * some details unavailable

    EXEMPLARY CLAIM(s): Show all 7 claims

      We claim:
      • 1. A hands-free active noise canceling headset comprising:
        • clamping means adapted to secure the headset to the users head,
        • at least one open back headset on said clamping means, said headset including a speaker means and a residual microphone means, and
        • a controller means operatively connected to said speaker means and
        • residual microphone means and adapted to both produce an anti-noise signal to said speaker means and adapted to receive signals from said residual microphone means representative of outward bound communications,
        • wherein said controller means includes
          • an LMS adapter, an adaptive filter means and an equalizer means to handle the anti-noise signals and communications signals from said residual
          • microphone means.

      RELATED U.S. APPLICATIONS: none
      PCT FILED:04/30/1992
      PCT NO.:PCT/US92/03441
      § 371 DATE: 10/27/1994
      § 102(e) DATE: 10/27/1994
      PCT PUB. DATE: 11/11/1993

      FOREIGN APPLICATION PRIORITY DATA: none
      FOREIGN REFERENCES: none
      OTHER REFERENCES: none
      PRIMARY/ASSISTANT EXAMINERS: Kuntz; Curtis; Harvey; Min Oh
      ADDED TO DATABASE: Dec. 16, 1997