Pinna proximity detection

Abstract

An integrated circuit for implementing at least a portion of a personal audio device may include an output for providing an output signal to a transducer, wherein the output signal includes a pilot signal, a microphone input for receiving a microphone signal from a microphone indicative of an output of the transducer, and a processing circuit. The processing circuit may be configured to implement a pilot signal control to apply an adjustment to the pilot signal as necessary to maintain the pilot signal at a substantially constant magnitude regardless of proximity of the transducer to a pinna and implement a proximity determination block configured to determine proximity of the transducer to the pinna based on the adjustment.

1 .- 42 . (canceled) 
     
     
         43 . An integrated circuit for proximity detection of a headset comprising a headset speaker, comprising:
 a first input for receiving a first signal from a first headset microphone, the first signal indicative of headset ambient sound;   a second input for receiving a second signal from a second headset microphone, the second signal indicative of sound present at an acoustic output of the headset speaker; and   circuitry for comparing a first sound energy of the first signal and a second sound energy of the second signal to determine whether the headset is on a user's ear.   
     
     
         44 . The integrated circuit of  claim 43 , wherein the first sound energy and the second sound energy are within a frequency band. 
     
     
         45 . The integrated circuit of  claim 44 , wherein the frequency band is 2 KHz to 5 KHz. 
     
     
         46 . The integrated circuit of  claim 43 , further comprising:
 a frequency-range isolating filter configured to receive and bandpass filter the first signal;   an envelope detector for detecting a signal envelope of the first signal in the bandpass filter range; and   a linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered first signal into a value given in terms of decibels relative to full-scale magnitude for the first signal.   
     
     
         47 . The integrated circuit of  claim 43 , further comprising:
 a frequency-range isolating filter configured to receive and bandpass filter the second signal;   an envelope detector for detecting a signal envelope of the second signal in the bandpass filter range; and   a linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered second signal into a value given in terms of decibels relative to full-scale magnitude for the second signal.   
     
     
         48 . The integrated circuit of  claim 43 , further comprising:
 a first frequency-range isolating filter configured to receive and bandpass filter the first signal;   a first envelope detector for detecting a signal envelope of the first signal in the bandpass filter range;   a first linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered first signal into a value given in terms of decibels relative to full-scale magnitude for the first signal;   a second frequency-range isolating filter configured to receive and bandpass filter the second signal;   a second envelope detector for detecting a signal envelope of the second signal in the bandpass filter range; and   a second linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered second signal into a value given in terms of decibels relative to full-scale magnitude for the second signal.   
     
     
         49 . The integrated circuit of  claim 43 , further comprising:
 a first frequency-range isolating filter configured to receive and bandpass filter the first signal;   a first envelope detector for detecting a signal envelope of the first signal in the bandpass filter range;   a first linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered first signal into a value given in terms of decibels relative to full-scale magnitude for the first signal;   a second frequency-range isolating filter configured to receive and bandpass filter the second signal;   a second envelope detector for detecting a signal envelope of the second signal in the bandpass filter range;   a second linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered second signal into a value given in terms of decibels relative to full-scale magnitude for the second signal;   circuitry for comparing a difference between the decibel values of the first and second signals and comparing the difference to a threshold value and outputting a control signal; and   a proximity decision block responsive to the control signal and configured to determine whether the headset is on a user's ear.   
     
     
         50 . A headset comprising:
 a headset speaker;   a first headset microphone;   a second headset microphone; and   an integrated circuit for proximity detection of the headset, comprising:
 a first input for receiving a first signal from the first headset microphone, the first signal indicative of headset ambient sound; 
 a second input for receiving a second signal from the second headset microphone, the second signal indicative of sound present at an acoustic output of the headset speaker; 
 circuitry for comparing a first sound energy of the first signal and a second sound energy of the second signal to determine whether the headset is on a user's ear. 
   
     
     
         51 . The headset of  claim 50 , wherein the first sound energy and the second sound energy are within a frequency band. 
     
     
         52 . The headset of  claim 51 , wherein the frequency band is 2 KHz to 5 KHz. 
     
     
         53 . The headset of  claim 50 , further comprising:
 a frequency-range isolating filter configured to receive and bandpass filter the first signal;   an envelope detector for detecting a signal envelope of the first signal in the bandpass filter range; and   a linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered first signal into a value given in terms of decibels relative to full-scale magnitude for the first signal.   
     
     
         54 . The headset of  claim 50 , further comprising:
 a frequency-range isolating filter configured to receive and bandpass filter the second signal;   an envelope detector for detecting a signal envelope of the second signal in the bandpass filter range; and   a linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered second signal into a value given in terms of decibels relative to full-scale magnitude for the second signal.   
     
     
         55 . The headset  claim 50 , further comprising:
 a first frequency-range isolating filter configured to receive and bandpass filter the first signal;   a first envelope detector for detecting a signal envelope of the first signal in the bandpass filter range;   a first linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered first signal into a value given in terms of decibels relative to full-scale magnitude for the first signal;   a second frequency-range isolating filter configured to receive and bandpass filter the second signal;   a second envelope detector for detecting a signal envelope of the second signal in the bandpass filter range; and   a second linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered second signal into a value given in terms of decibels relative to full-scale magnitude for the second signal.   
     
     
         56 . The headset of  claim 50 , further comprising:
 a first frequency-range isolating filter configured to receive and bandpass filter the first signal;   a first envelope detector for detecting a signal envelope of the first signal in the bandpass filter range;   a first linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered first signal into a value given in terms of decibels relative to full-scale magnitude for the first signal;   a second frequency-range isolating filter configured to receive and bandpass filter the second signal;   a second envelope detector for detecting a signal envelope of the second signal in the bandpass filter range;   a second linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered second signal into a value given in terms of decibels relative to full-scale magnitude for the second signal;   circuitry for comparing a difference between the decibel values of the first and second signals and comparing the difference to a threshold value and outputting a control signal; and   a proximity decision block responsive to the control signal and configured to determine whether the headset is on a user's ear.   
     
     
         57 . The headset of  claim 50 , wherein the headset is a wired headset for communicatively coupling to an audio device. 
     
     
         58 . The headset of  claim 50 , wherein the headset is a wireless headset for communicatively coupling to an audio device. 
     
     
         59 . The headset of  claim 50 , wherein the headset is a wireless earbud for communicatively coupling to an audio device. 
     
     
         60 . An integrated circuit for proximity detection of a headset comprising a first headset speaker and a second headset speaker, comprising:
 a first input for receiving a first signal from a first headset microphone, the first signal indicative of first headset ambient sound;   a second input for receiving a second signal from a second headset microphone, the second signal indicative of sound present at an acoustic output of the first headset speaker;   a third input for receiving a third signal from a third headset microphone, the third signal indicative of second headset ambient sound;   a fourth input for receiving a fourth signal from a fourth headset microphone, the fourth signal indicative of sound present at an acoustic output of a second headset speaker;   circuitry for comparing a first sound energy of the first signal to a second sound energy of the second signal and comparing a third sound energy of the third signal and a fourth sound energy of the fourth signal to determine whether the headset is on a user's ear.   
     
     
         61 . The integrated circuit of  claim 60 , wherein the first sound energy and the second sound energy are within a frequency band. 
     
     
         62 . The integrated circuit of  claim 61 , wherein the frequency band is 2 KHz to 5 KHz. 
     
     
         63 . The integrated circuit of  claim 60 , further comprising:
 a frequency-range isolating filter configured to receive and bandpass filter the first signal;   an envelope detector for detecting a signal envelope of the first signal in the bandpass filter range; and   a linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered first signal into a value given in terms of decibels relative to full-scale magnitude for the first signal.   
     
     
         64 . The integrated circuit of  claim 60 , further comprising:
 a frequency-range isolating filter configured to receive and bandpass filter the second signal;   an envelope detector for detecting a signal envelope of the second signal in the bandpass filter range; and   a linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered second signal into a value given in terms of decibels relative to full-scale magnitude for the second signal.   
     
     
         65 . The integrated circuit of  claim 60 , further comprising:
 a first frequency-range isolating filter configured to receive and bandpass filter the first signal;   a first envelope detector for detecting a signal envelope of the first signal in the bandpass filter range;   a first linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered first signal into a value given in terms of decibels relative to full-scale magnitude for the first signal;   a second frequency-range isolating filter configured to receive and bandpass filter the second signal;   a second envelope detector for detecting a signal envelope of the second signal in the bandpass filter range; and   a second linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered second signal into a value given in terms of decibels relative to full-scale magnitude for the second signal.   
     
     
         66 . The integrated circuit of  claim 60 , further comprising:
 a first frequency-range isolating filter configured to receive and bandpass filter the first signal;   a first envelope detector for detecting a signal envelope of the first signal in the bandpass filter range;   a first linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered first signal into a value given in terms of decibels relative to full-scale magnitude for the first signal;   a second frequency-range isolating filter configured to receive and bandpass filter the second signal;   a second envelope detector for detecting a signal envelope of the second signal in the bandpass filter range;   a second linear-to-decibel converter configured to convert the envelope detected, bandpass-filtered second signal into a value given in terms of decibels relative to full-scale magnitude for the second signal;   circuitry for comparing a difference between the decibel values of the first and second signals and comparing the difference to a threshold value and outputting a control signal; and   a proximity decision block responsive to the control signal and configured to determine whether the headset is on a user's ear.   
     
     
         67 . The integrated circuit of  claim 60 , wherein the headset is a wired headset for communicatively coupling to an audio device. 
     
     
         68 . The integrated circuit of  claim 60 , wherein the headset is a wireless headset for communicatively coupling to an audio device. 
     
     
         69 . The integrated circuit of  claim 60 , wherein the headset is a pair of wireless earbuds for communicatively coupling to an audio device.