Patent ID: 11889267
Assignee: AMS AG
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A noise cancellation enabled audio system for tonal tinnitus treatment using ambient noise, comprising:
an audio processor,
at least one filter having an adjustable filter function,
an ear mountable playback device further comprising a speaker and at least one feedforward microphone, and
an amplifier coupled between the audio processor and the speaker,
wherein the audio processor is configured to:
receive an input signal from the feedforward microphone indicative of ambient noise,
determine a filter transfer function to realize a predetermined target transfer function, wherein the target transfer function is configured to attenuate and/or amplify the input signal in a predetermined frequency range, and
adjusting the filter function depending on the filter transfer function; and
wherein the filter is configured to:
provide a system output signal by filtering the input signal depending on the filter function, and,
wherein:
the audio processor is provided with acoustic transfer functions between an ambient sound source creating the ambient noise and an eardrum exposed to the speaker, and
the audio processor is configured to determine the filter transfer function by compensating for the acoustic transfer functions, and
wherein the acoustic transfer functions comprise:
a first acoustic transfer function of the feedforward microphone, denoted HM(s),
a second acoustic transfer function of the amplifier, denoted HA(s),
a third acoustic transfer function of the speaker, denoted HS(s),
a fourth acoustic transfer function of the ear mountable playback device, denoted HH(s); and wherein:
the filter transfer function, denoted HF(s), is determined as, H
    F
   
   (
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   )
  
  =
  
   
    
     
      H
      T
     
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     s
     )
    
    -
    
     
      H
      H
     
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     s
     )
    
   
   
    
     
      H
      M
     
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     s
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    ·
    
     
      H
      A
     
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    ·
    
     
      H
      S
     
     (
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wherein HT(s) denotes the target transfer function.