External microphone array and hearing aid using it

Patent metadata

Field	Value
Publication number	US-9510112-B2
Application number	US-201314099242-A
Country	US
Kind code	B2
Filing date	Dec 6, 2013
Priority date	Aug 19, 2013
Publication date	Nov 29, 2016
Grant date	Nov 29, 2016

Abstract

An external microphone array is configured to be used with a hearing aid and comprises a number of microphones configured to detect one or more sound signals from a sound source and means for wirelessly sending the detected sound signal to at least one hearing aid. The external microphone array comprises means for automatically determining the direction of the sound source either by: a) receiving a wireless signal transmitted from a remote control; b) by receiving acoustic signals picked up by the hearing aid(s) and by further comparing the signals with signals received by the external microphone array. The external microphone array may e.g. take the form of a sphere, a hemi-sphere or a neckband.

First claim

The invention claimed is:

1. An external microphone array configured to be used with a hearing aid, the external microphone array comprising:
a number of microphones configured to detect one or more sound signals from a sound source; and
transmitter circuitry for wirelessly transmitting the detected sound signal to at least one hearing aid; and
a processing unit configured to automatically determine a direction of the sound source relative to the at least one hearing aid, by:
receiving a wireless signal transmitted from a remote control arranged between the external microphone array and the at least one hearing aid, the wireless signal including a direction from the external microphone array to the remote control,
determining a direction of the sound source relative to the external microphone array, and
determining the direction of the sound source relative to the at least one hearing aid based on information about the direction of the sound source relative to the external microphone array and the wireless signal received from the remote control.

2. An external microphone array according to claim 1 , wherein the external microphone array has a spherical geometry.

3. An external microphone array according to claim 1 , wherein the external microphone array has a hemi-spherical geometry.

4. An external microphone array according to claim 1 , wherein a plurality of microphones are provided at the surface of the spherical or hemi-spherical geometry of the external microphone array.

5. An external microphone array according to claim 1 , forming part of a communication device.

6. An external microphone array according to claim 1 forming part of a neckband.

7. An external microphone array according to claim 6 wherein the neckband comprises an array of microphones distributed around the head of the user.

8. An external microphone array according to claim 1 comprising a user interface.

9. A hearing aid system, comprising:
at least one hearing aid; and
an external microphone array according to claim 1 .

10. A hearing aid system according to claim 9 , further comprising:
a remote control configured to provide a visual acoustical control, where the remote control is a smart phone or a tablet.

11. A hearing aid system according to claim 9 , wherein
the at least one hearing aid includes a signal processing unit configured to analyze acoustic signals picked up by the at least one hearing aid to automatically determine the direction of the sound source.

12. A hearing aid system according to claim 9 , comprising a control device provided with a classifier for classification of signals detected from a sound source and an analyzer configured to analyze the classified signals.

13. A hearing aid system according to claim 12 comprising means for tagging classified signals and the associated sound sources, where the hearing aid system further comprises means for using this information to steer the prioritisation and attenuation of sound sources.

14. A hearing aid system according to claim 9 , further comprising:
an external microphone or a second external microphone array configured to be worn by a person, which external microphone or second external microphone array is provided with a voice detection system configured to detect if the person wearing the external microphone or second external microphone array is speaking, where the hearing aid system is configured to transmit signals to the at least one hearing aid when the person is speaking, where the hearing aid system is configured not to transmit signals to the at least one hearing aid when the person is not speaking.

15. A hearing aid system according to claim 12 , wherein the hearing aid system comprises a voice detector configured to detect a voice of the person wearing an external microphone or the external microphone array.

16. A hearing aid system according to claim 9 , wherein
the hearing aid system comprises an external microphone or a second external microphone array, and
the system is configured to alert the user of the at least one hearing aid by providing a signal perceivable to the user in the at least one hearing aid when a wireless connection of the external microphone or the external microphone array to the at least one hearing aid is lost.

17. A hearing aid system according to claim 9 , applying a head related transfer function (HRTF) to the signals received by the microphone array and providing signals to the at least one hearing aid in such a way that the processed signals basically appear as if they come from the direction of the sound source.

18. A method of operating an external microphone array configured to be used with at least one hearing aid, which microphone array includes a number of microphones configured to detect a sound signal from a sound source and a transceiver configured to wirelessly send the detected sound signal to the at least one hearing aid, the method comprising:
positioning a remote control between the external microphone array and the at least one hearing aid;
receiving a wireless signal transmitted from the remote control between the external microphone array and the at least one hearing aid, the wireless signal including a direction from the external microphone array to the remote control;
determining a direction of the sound source relative to the external microphone array; and
determining the direction of the sound source relative to the at least one hearing aid based on information about the direction of the sound source relative to the external microphone array and the wireless signal received from the remote control.

19. The external microphone array according to claim 1 , wherein, to determine the direction of the sound source relative to the external microphone array, the external microphone array is configured to
receive wireless signals representing acoustic signals from the sound source picked up by the at least one hearing aid,
shift in a number of steps, through an angle of space, a predefined directional characteristic, when the external microphone array is in a sound source search mode,
compare by a cross-correlation, in each of the number of steps, the wireless signals representing the acoustic signals picked up the at least one hearing aid with corresponding acoustic signals received by the external microphone array, and
determining, by the cross-correlation, a best correlation corresponding to the direction of the sound source relative to the external microphone array.

20. The external microphone array according to claim 19 , wherein
the external microphone array is configured to enter the sound source search mode by receiving a mode control input signal which is automatically generated by at least one of
a movement of the user's head, and
movement sensor located in the at least one hearing aid.

21. The method according to claim 18 , wherein the determining the direction of the sound source relative to the external microphone array comprises:
receiving wireless signals representing acoustic signals from the sound source picked up by the at least one hearing aid;
shifting in a number of steps, through an angle of space, a predefined directional characteristic, when the external microphone array is in a sound source search mode;
comparing by a cross-correlation, in each of the number of steps, the wireless signals representing the acoustic signals picked up the at least one hearing aid with corresponding acoustic signals received by the external microphone array, a

Assignees

• Oticon As

Inventors

• Petersen Svend Oscar
• Pedersen Mette Boel
• Aldaz Gabriel
• Bergmann Martin
• Pedersen Regin Kopp
• Sommer Peter

Classifications

• H04R25/554 Primary

  using a wireless connection, e.g. between microphone and amplifier or using Tcoils · CPC title

• H04R25/407

  Circuits for combining signals of a plurality of transducers · CPC title

• H04R2225/43

  Signal processing in hearing aids to enhance the speech intelligibility · CPC title

• H04R25/558

  Remote control, e.g. of amplification, frequency · CPC title

• H04R2201/401

  2D or 3D arrays of transducers · CPC title