×

Hearing compensation system incorporating signal processing techniques

  • US 8,085,959 B2
  • Filed: 09/08/2004
  • Issued: 12/27/2011
  • Est. Priority Date: 07/08/1994
  • Status: Expired due to Fees
First Claim
Patent Images

1. An audio output device, comprising:

  • an acoustic input transducer for converting input acoustical energy into output electrical signals corresponding to the input acoustical energy;

    a plurality of audio bandpass filters coupled to receive said electrical signals, each of said audio bandpass filters having an output; and

    a plurality of multiplicative automatic gain control (MAGC) circuits coupled to a respective output of one of said plurality of audio bandpass filters, at least one of said MAGC circuits including a hearing compensation circuit and a noise suppression circuit, and wherein at least one of said MAGC circuits include;

    a first circuit to obtain an input envelope amplitude from the coupled audio bandpass filter output;

    a second circuit responsive to the input envelope amplitude to provide a logarithm of the input envelope amplitude;

    a noise estimation circuit for obtaining an estimate of noise; and

    a subtraction circuit to subtract the estimate of noise from the logarithm of the input envelope amplitude;

    wherein an acoustic signal having approximately a constant amplitude for a period of a predetermined amount of time is attenuated through interaction of said hearing compensation circuit and said noise suppression circuit.

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