ADAPTIVE FEEDBACK GAIN CORRECTION

• US 20100177917A1
• Filed: 01/13/2009
• Published: 07/15/2010
• Est. Priority Date: 12/23/2008
• Status: Active Grant

• Current Assignee: GN Hearing A/S (GN Store Nord A/S)
• Original Assignee: GN Resound A/S (GN Store Nord A/S)
• Inventors: VAN DER WERF, Erik Cornelis Diederik
• Granted Patent: US 10,602,282 B2
• Time in Patent Office: Days
• US Class Current: 381/318
• CPC Class Codes: H04R 25/305 Self-monitoring or self-testing
• CPC Class Codes: H04R 25/453 electronically
• CPC Class Codes: H04R 25/70 Adaptation of deaf aid to hearing loss, e.g. initial electronic fitting

Abstract

A hearing aid includes a signal processor, a input transducer electrically connected to the signal processor, a receiver electrically connected to the signal processor, an adaptive feedback cancellation filter configured to suppress feedback from a signal path between the receiver and the input transducer, and a feedback gain correction unit configured for adjusting a gain parameter of the signal processor based at least in part on coefficients of the adaptive feedback cancellation filter. A method of adjusting a gain parameter of a signal processor of a hearing aid includes monitoring filter coefficients of a feedback cancellation filter of the hearing aid, and adjusting the gain parameter of the signal processor in dependence of the monitored filter coefficients.

Claims

1. A hearing aid comprising:

a signal processor;

a input transducer electrically connected to the signal processor;

a receiver electrically connected to the signal processor;

an adaptive feedback cancellation filter configured to suppress feedback from a signal path between the receiver and the input transducer; and

a feedback gain correction unit configured for adjusting a gain parameter of the signal processor based at least in part on coefficients of the adaptive feedback cancellation filter.

2. The hearing aid according to claim 1, wherein the adjustment of the gain parameter of the signal processor comprises a scaling of an input signal to the signal processor.

3. The hearing aid according to claim 1, wherein the feedback gain correction unit is configured for adjusting the gain parameter further based at least in part on a set of reference coefficients.

4. The hearing aid according to claim 1, wherein the feedback gain correction unit is configured for adjusting the gain parameter further based at least in part on a deviation of the coefficients of the adaptive feedback cancellation filter from reference filter coefficients.

5. The hearing aid according to claim 3, wherein the reference coefficients are established by measurements during a fitting situation and/or by estimation based on previous scaling.

6. The hearing aid according to claim 1, further comprising attack and release filters configured for smoothing the gain parameter.

7. A method of adjusting a gain parameter of a signal processor of a hearing aid, comprising:

monitoring filter coefficients of a feedback cancellation filter of the hearing aid, and

adjusting the gain parameter of the signal processor in dependence of the monitored filter coefficients.

8. The method according to claim 7, wherein the act of adjusting the gain parameter of the signal processor comprises scaling an input signal to the signal processor.

9. The method according to claim 7, wherein the act of adjusting the gain parameter of the signal processor is performed based at least in part on a set of reference filter coefficients.

10. The method according to claim 7, wherein the act of adjusting the gain parameter is performed based at least in part on a deviation of the filter coefficients of the feedback cancellation filter from reference filter coefficients.

11. The method according to claim 7, wherein the act of adjusting the gain parameter of the signal processor is performed band-wise in a plurality of frequency bands.

12. The method according to claim 7, wherein the act of adjusting the gain parameter of the signal processor is performed in a broad band.

13. The method according to claim 7, further comprising performing a feedback cancellation using the feedback cancellation unit.

14. The method of claim 13, wherein the feedback cancellation is performed by subtracting an estimated feedback signal from an incoming signal.

15. The method according to any claim 7, further comprising performing a noise reduction, a loudness restoration, or both, using the signal processor.