Apparatus and method for protecting hearing from noise while enhancing a sound signal of interest

• US 8,229,740 B2
• Filed: 09/07/2005
• Issued: 07/24/2012
• Est. Priority Date: 09/07/2004
• Status: Active Grant

• Current Assignee: Sensear Pty., Ltd.
• Original Assignee: Sensear Pty., Ltd.
• Inventors: Nordholm, Sven Erik, Fynn, Kevin
• Primary Examiner(s): SKED, MATTHEW J
• Application Number:
  US11/574,665
• Publication Number:
  US 20080004872A1
• Time in Patent Office: 2,512 Days
• Field of Search: None
• US Class Current: 704/226
• CPC Class Codes: A61F 11/145 electric, e.g. for active noise reduction
• CPC Class Codes: G10K 11/17823 Reference signals, e.g. ambient acoustic environment
• CPC Class Codes: G10K 11/17837 by retaining part of the ambient acoustic environment, e.g. speech or alarm signals that the user needs to hear
• CPC Class Codes: G10K 11/17857 Geometric disposition, e.g. placement of microphones
• CPC Class Codes: G10K 11/17861 using additional means for damping sound, e.g. using sound absorbing panels
• CPC Class Codes: G10K 11/17881 the reference signal being an acoustic signal, e.g. recorded with a microphone
• CPC Class Codes: G10K 2210/1081 Earphones, e.g. for telephones, ear protectors or headsets
• CPC Class Codes: H04R 1/1008 Earpieces of the supra-aural or circum-aural type
• CPC Class Codes: H04R 1/1083 Reduction of ambient noise active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06
• CPC Class Codes: H04R 2410/05 Noise reduction with a separate noise microphone
• CPC Class Codes: H04R 2430/20 Processing of the output signals of the acoustic transducers of an array for obtaining a desired directivity characteristic H04R2203/12 takes precedence
• CPC Class Codes: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
• CPC Class Codes: H04R 5/027 Spatial or constructional arrangements of microphones, e.g. in dummy heads
• CPC Class Codes: H04R 5/0335 Earpiece support, e.g. headbands or neckrests for monophonic headphones H04R1/105

Abstract

An apparatus for sound enhancement has at least two microphones (9) that provide a directional microphone array which is arranged to be pointed in the direction of a sound source. The directional microphone array thereby receives sound emitted by the sound source and generates sound signals. A processor (20) processors the sound signals generated by the microphone array to enhance the sound received by the directional microphone array from the sound source relative to other sound received by the directional microphone array. The processor (20) generates a corresponding enhanced signal (ES). Loud speakers (22) reproduce the enhanced signal as audible sound. Furthermore, sound suppression devices (7, 7a) are provided to suppress ambient should from reaching the eardrums of the user. This sound suppression acts in conjunction with the directional microphone array and the processor (20) which enhance the SOI to provide a listening environment in which the SOI is enhanced.

Claims

1. A hearing protector for providing enhancement of a sound signal of interest and protection from at least one other sound for a wearer of the hearing protector in an environment that includes high level noise in addition to the sound signal of interest comprising:

at least two fixed microphones adapted to work together to provide a directional microphone array arranged to be pointed in the wearer'"'"'s look direction for receiving the sound signal of interest and generating sound signals corresponding to sounds detected at the array,

a processor to process the sound signals generated by said directional microphone array to enhance the sound signal of interest relative to a signal generated by the high level noise and generate a corresponding enhanced signal,

at least one speaker operatively connected to the processor for presenting sound based on the enhanced signal to the wearer, and

at least one passive sound suppressor arranged to be located adjacent each ear of a wearer to suppress the high level noise reaching the ear drums of the wearer, said suppressor able to provide passive sound suppression of at least 15 dB.

2. A hearing protector according to claim 1, wherein the passive sound suppressor provides passive sound suppression in the range of from substantially 15 dB to substantially 50 dB.

3. A hearing protector according to claim 1, wherein said processor provides adaptive processing of the sound signals generated by said directional microphone array dependent upon the levels of ambient sound in the environment in which the sound signal of interest is located.

4. A hearing protector according to claim 1, wherein said processor provides spatial processing, temporal processing and post processing of the sound signals generated by said directional microphone array.

5. A hearing protector according to claim 1, wherein said speaker is arranged to be provided adjacent at least one ear of the wearer.

6. A hearing protector according to claim 1, wherein said hearing protector comprises an ear muff arrangement and wherein said sound suppressor comprises ear muffs.

7. A hearing protector according to claim 1, wherein said sound suppressor comprises ear plugs.

8. A hearing protector according to claim 1, wherein at least one microphone is provided adjacent each sound suppressor.

9. A hearing protector according to claim 8, wherein a controller circuit is provided which is arranged to receive said enhanced signal prior to said enhanced signal being fed to said at least one speaker and said controller circuit is arranged to receive sound signals generated by each said microphone provided adjacent each said sound suppressor prior to being fed to said at least one speaker, and wherein said controller circuit generates cancellation signals to cancel the sound signals generated by each said microphone such that reproduction of these sounds by said at least one speaker is attenuated.

10. An apparatus according to claim 9, wherein said controller circuit comprises a respective controller circuit for each said speaker.

11. A hearing protector according to claim 1, wherein said sound suppressor comprises ear muffs and ear plugs.

12. A method for providing enhancement of a sound signal of interest and protection from at least one other sound for a person in an environment that includes high level noise in addition to the sound signal of interest, the method comprising:

providing at least two fixed microphones working together to provide a directional microphone array arranged to be pointed in the persons look direction for receiving the sound signal of interest,

receiving the sound signal of interest at the microphone array,

generating sound signals corresponding to sound received at said array,

processing the sound signals generated at said array to enhance the sound signal of interest relative to a signal generated by the high level noise,

generating a corresponding enhanced signal,

reproducing the enhanced signal and presenting it to the person, and

passively suppressing the high level noise at the person'"'"'s ears by at least 15 dB.

13. A method according to claim 12, wherein passively suppressing the high level noise comprises providing sound suppression in the range of from substantially 15 dB to substantially 50 dB.

14. A method according to claim 12, wherein processing the sound signals comprises performing adaptive processing of the sound signals generated by said directional microphone array dependent upon the levels of the ambient sound in the environment in which the sound signal of interest is located.

15. A method according to claim 12, wherein processing the sound signals comprises performing spatial processing, temporal processing and post processing of the sound signals generated by said directional microphone array.

16. A method according to claim 12, further comprising:

processing sound signals that are representative of ambient sound that are not suppressed, and

generating cancellation signals to cancel the ambient sound that is not suppressed such that reproduction of those sounds is attenuated.

17. A method according to claim 12, wherein passively suppressing the high level noise comprises providing ear plugs for the wearer'"'"'s ears.

18. A method according to claim 12, wherein passively suppressing the high level noise comprises providing ear muffs for the wearer'"'"'s ears.

19. A method according to claim 12, wherein passively suppressing the high level noise comprises providing ear muffs and ear plugs for the wearer'"'"'s ears.