Hearing enhancement system and components thereof

• US 8,416,959 B2
• Filed: 09/01/2009
• Issued: 04/09/2013
• Est. Priority Date: 08/17/2009
• Status: Active Grant

• Current Assignee: Spear Labs, LLC
• Original Assignee: Spear Labs, LLC
• Inventors: Lott, Dale, Newton, William T.
• Primary Examiner(s): Chin, Vivian
• Assistant Examiner(s): Zhang, Leshui
• Application Number:
  US12/551,805
• Publication Number:
  US 20110038496A1
• Time in Patent Office: 1,316 Days
• Field of Search: 381/71.6, 381/71.4, 381/71.3, 381/71.1, 381/71.11, 381/71.12, 381/71.14, 381/92, 381/74, 381/72, 381/122, 381/98, 381/103, 381/106, 381/111, 381/121, 381/120, 381/309, 381/26, 381/95, 37940601-40616, 455/569.2, 455/570, 455/63.1, 455/114.2, 455/296
• US Class Current: 381/71.6
• CPC Class Codes: H04R 5/033 Headphones for stereophonic communication details thereof, e.g. relating to batteries, cables or control elements H04R1/10

Abstract

A circuit includes a microphone circuit, an audio processing module, a digital audio processing module, and an active noise reduction (ANR) circuit. The microphone circuit receives acoustic vibrations and generates an audio signal therefrom. The audio processing module generates a representation of the audio signal. The digital audio processing module compensates the representation of the audio signal based on hearing compensation data to produce a hearing compensated audio signal. The ANR circuit receives the hearing compensated audio signal and an ANR signal. The ANR circuit further functions to adjust the hearing compensated audio signal based on the ANR signal to produce an output audio signal, wherein the ANR signal is generated based on the output audio signal.

Claims

1. A circuit comprises:

a microphone circuit operably coupled to;

receive acoustic vibrations in a proximal environment; and

generate an audio signal based on the acoustic vibration;

an audio processing module operably coupled to generate a representation of the audio signal;

a digital audio processing module operably coupled to compensate the representation of the audio signal based on hearing compensation data to produce a hearing compensated audio signal; and

an active noise reduction (ANR) circuit including;

an ANR microphone circuit operably coupled to;

receive the output audio signal; and

generate an ANR signal based on the output audio signal;

a first filter operably coupled to high pass filter the hearing compensated audio signal to produce a filtered hearing compensated audio signal;

a summing module operably coupled to sum the filtered hearing compensated audio signal and the ANR signal to produce a summed audio signal;

a second filter operably coupled to filter the summed audio signal to produce a filtered summed audio signal;

an operational amplifier having an inverting input, a non-inverting input, and an output, wherein the non-inverting input receives the summed audio signal and the output outputs an output audio signal;

a feedback filter operably coupled to filter the output audio signal to produce a feedback signal; and

a third filter operably coupled to high pass filter the hearing compensated audio signal to produce a high pass filtered hearing compensated audio signal, wherein the feedback signal and the high pass filtered hearing compensated audio signal are received by the inverting input of the operational amplifier.

2. The circuit of claim 1, wherein the ANR circuit further comprises:

a fourth filter operably coupled to high pass filter the output audio signal to produce a high pass filtered output audio signal;

a signal detector operably coupled to convert the high pass filtered output audio signal into a proportional direct current (DC) signal; and

a comparison circuit operably coupled to disable the ANR circuit when the proportional DC signal compares unfavorably to a high frequency feedback threshold voltage.

3. The circuit of claim 1 further comprises the audio processing module generating the representation of the audio signal by at least one of:

performing a hear-through function that includes;

performing multiple band compression; and

performing noise reduction; and

performing multiple band equalization.

4. The circuit of claim 1 further comprises at least one of the audio processing module and the digital audio processing module digitally performing one or more of:

multi-band compression;

multi-band equalization;

noise reduction; and

multi-hearing modes for producing the hearing compensated audio signal based on the hearing compensation data.

5. The circuit of claim 1, wherein the microphone circuit comprises:

one or more left microphones operably coupled to generate a left analog audio signal based acoustic vibrations;

one or more right microphones operably coupled to generate a right analog audio signal based acoustic vibrations; and

microphone compensation circuitry operably coupled to compensate the left and right analog audio signals to produce the audio signal.

6. The circuit of claim 5 further comprises the microphone compensation circuitry operably coupled to:

compensate the left and right analog audio signals based on a natural cardioid pattern to produce the audio signal having three-dimensional characteristics.

7. The circuit of claim 5 further comprises:

a transient detect module operably coupled to detect a loud transient within at least one of the first and second analog audio signals of the left or the right ear unit; and

when the loud transient is detected, the transient detect module provides a signal to the audio processing module to compress the left and right audio signals to a desired level.

8. The circuit of claim 1 further comprises:

a stereo output operably coupled to output a representation of the output audio signal, wherein the stereo output is capable of connecting to a set of ear bud speakers.

9. The circuit of claim 1 further comprises:

an auxiliary input operably coupled to receive an auxiliary audio signal from a communication device; and

the audio processing module operably coupled to;

mix the audio signal and the auxiliary audio signal to produce a mixed audio signal;

generate a second representation of the mixed audio signal;

the digital audio processing module operably coupled to compensate the second representation of the mixed audio signal based on the hearing compensation data to produce a hearing compensated mixed audio signal; and

the ANR circuit operably coupled to;

receive the hearing compensated mixed audio signal;

receive the ANR signal; and

adjust the hearing compensated mixed audio signal based on the ANR signal to produce a mixed output audio signal, wherein the ANR signal is generated based on the output audio signal.

10. The circuit of claim 1 further comprises:

a second microphone circuit operably coupled to;

receive spoken audible sounds; and

generate a voice signal based on the spoken audible sounds; and

a processing module operably coupled to convert the voice signal into a digital audio signal.

11. A hearing enhancement system comprises:

a left ear unit that includes;

a left microphone circuit operably coupled to;

receive left acoustic vibrations in a proximal environment; and

generate a left audio signal based on the left acoustic vibration;

a left audio processing module, when enabled, is operably coupled to generate a representation of the left audio signal;

a left digital audio processing module, when enabled, is operably coupled to compensate the representation of the left audio signal based on left hearing compensation data to produce a left hearing compensated audio signal; and

a left active noise reduction (ANR) circuit, when enabled, is operably coupled to;

receive the left hearing compensated audio signal;

receive a left ANR signal; and

adjust the left hearing compensated audio signal based on the left ANR signal to produce a left output audio signal, wherein the left ANR signal is generated based on the left output audio signal;

a right ear unit that includes;

a right microphone circuit operably coupled to;

receive right acoustic vibrations in the proximal environment; and

generate a right audio signal based on the right acoustic vibration;

a right audio processing module, when enabled, is operably coupled to generate a representation of the right audio signal;

a right digital audio processing module, when enabled, is operably coupled to compensate the representation of the right audio signal based on right hearing compensation data to produce a right hearing compensated audio signal; and

a right ANR circuit, when enabled, is operably coupled to;

receive the right hearing compensated audio signal;

receive a right ANR signal; and

adjust the right hearing compensated audio signal based on the right ANR signal to produce a right output audio signal, wherein the right ANR signal is generated based on the right output audio signal; and

a control unit operably coupled to selectively enable one or more of the left and right audio processing modules, the left and right digital audio processing modules, and the left and right ANR circuits, wherein each of the left and right ANR circuits comprises;

an ANR microphone circuit operably coupled to;

receive the left or right output audio signal; and

generate the left or right ANR signal based on the left or right output audio signal;

a first filter operably coupled to high pass filter the left or right hearing compensated audio signal to produce a filtered hearing compensated audio signal;

a summing module operably coupled to sum the filtered hearing compensated audio signal and the left or right ANR signal to produce a summed audio signal;

a second filter operably coupled to filter the summed audio signal to produce a filtered summed audio signal;

an operational amplifier having an inverting input, a non-inverting input, and an output, wherein the non-inverting input receives the summed audio signal and the output outputs the left or right output audio signal;

a feedback filter operably coupled to filter the left or right output audio signal to produce a feedback signal; and

a third filter operably coupled to high pass filter the left or right hearing compensated audio signal to produce a high pass filtered hearing compensated audio signal, wherein the feedback signal and the high pass filtered hearing compensated audio signal are received by the inverting input of the operational amplifier.

12. The hearing enhancement system of claim 11 further comprises:

the left ear unit including;

a left cup-shaped housing that houses the left microphone circuit, the left audio processing module, the left digital audio processing module, and the left ANR circuit; and

a left seal coupled to the left cup-shared housing; and

the right ear unit including;

a right cup-shaped housing that houses the right microphone circuit, the right audio processing module, the right digital audio processing module, and the right ANR circuit; and

a right seal coupled to the right cup-shared housing.

13. The hearing enhancement system of claim 11, wherein each of the left and right ANR circuit further comprises:

a fourth filter operably coupled to high pass filter the left and right output audio signal to produce a high pass filtered output audio signal;

a signal detector operably coupled to convert the high pass filtered output audio signal into a proportional direct current (DC) signal; and

a comparison circuit operably coupled to disable the left and right ANR circuit when the proportional DC signal compares unfavorably to a high frequency feedback threshold voltage.

14. The hearing enhancement system of claim 11 further comprises the left and right audio processing module generating the representation of the left and right audio signal by at least one of:

performing a hear-through function that includes;

performing multiple band compression; and

performing noise reduction; and

performing multiple band equalization.

15. The hearing enhancement system of claim 11 further comprises at least one of the left and right audio processing module and the left and right digital audio processing module digitally performing one or more of:

multi-band compression;

multi-band equalization;

noise reduction; and

multi-hearing modes for producing the left and right hearing compensated audio signal based on the left and right hearing compensation data.

16. The hearing enhancement system of claim 11, wherein the left and right microphone circuit comprises:

one or more first microphones operably coupled to generate a first analog audio signal based acoustic vibrations;

one or more second microphones operably coupled to generate a second analog audio signal based acoustic vibrations; and

microphone compensation circuitry operably coupled to compensate the first and second analog audio signals to produce the left and right audio signal.

17. The hearing enhancement system of claim 16 further comprises the microphone compensation circuitry operably coupled to:

compensate the first and second analog audio signals based on a natural cardioid pattern to produce the left and right audio signal having three-dimensional characteristics.

18. The hearing enhancement system of claim 16 further comprises:

a transient detect module operably coupled to detect a loud transient within at least one of the first and second analog audio signals of the left or the right ear unit; and

when the loud transient is detected, the transient detect module provides a signal to the audio processing module to compress the left and right audio signals to a desired level.

19. The hearing enhancement system of claim 11 further comprises:

a stereo output operably coupled to output the left and right output audio signals, wherein the stereo output is capable of connecting to a set of ear bud speakers.

20. The hearing enhancement system of claim 11 further comprises:

an auxiliary input operably coupled to receive an auxiliary audio signal from a communication device; and

at least one of the left and right audio processing modules operably coupled to;

mix at least one of the left and right audio signals with the auxiliary audio signal to produce a mixed audio signal;

generate a second representation of the mixed audio signal;

at least one of the left and right digital audio processing modules operably coupled to compensate the second representation of the mixed audio signal based on at least one of the left and right hearing compensation data to produce a hearing compensated mixed audio signal; and

at least one of the left and right ANR circuit operably coupled to;

receive the hearing compensated mixed audio signal;

receive at least one of the left and right ANR signals; and

adjust the hearing compensated mixed audio signal based on the at least one of the left and right ANR signals to produce a mixed output audio signal.

21. The hearing enhancement system of claim 11 further comprises:

a second microphone circuit operably coupled to;

receive spoken audible sounds; and

generate a voice signal based on the spoken audible sounds; and

a processing module operably coupled to convert the voice signal into a digital audio signal.