×

Frequency-dependent ANR reference sound compression

  • US 9,123,320 B2
  • Filed: 08/08/2013
  • Issued: 09/01/2015
  • Est. Priority Date: 04/28/2009
  • Status: Active Grant
First Claim
Patent Images

1. An active noise reduction (ANR) circuit comprising:

  • a digital feed-forward ANR pathway coupled to a feed-forward microphone, to detect environmental sounds in an environment external to a casing, and coupled to a first acoustic driver to output sounds within the casing; and

    a user input;

    wherein the digital feed-forward ANR pathway applies a filter using a first set of coefficients to convert signals from the feed-forward microphone to feed-forward anti-noise sounds to reduce environmental sounds within the casing, andin response to activation of the user input, the digital feed-forward ANR pathway applies the filter using a second set of coefficients,the second set of coefficients reducing the degree of feed-forward ANR to enable human speech sounds in the environment external to the casing to be conveyed from the feed-forward microphone to the acoustic driver with less reduction than provided by the first set of coefficients.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×