Hearing assistance devices with echo cancellation

• US 9,294,851 B2
• Filed: 06/09/2014
• Issued: 03/22/2016
• Est. Priority Date: 03/12/2009
• Status: Active Grant

• Current Assignee: Starkey Laboratories Incorporated
• Original Assignee: Starkey Laboratories Incorporated
• Inventors: Kindred, Jon S., Solum, Jeffrey Paul
• Primary Examiner(s): Page, Dale E
• Application Number:
  US14/299,349
• Publication Number:
  US 20150010180A1
• Time in Patent Office: 652 Days
• US Class Current: 1/1
• CPC Class Codes: H04M 1/72478 for hearing-impaired users
• CPC Class Codes: H04R 1/1091 Details not provided for in groups H04R1/1008 - H04R1/1083
• CPC Class Codes: H04R 2225/55 Communication between hearing aids and external devices via a network for data exchange
• CPC Class Codes: H04R 2460/01 Hearing devices using active noise cancellation
• 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 25/453 electronically
• CPC Class Codes: H04R 25/505 using digital signal processing
• CPC Class Codes: H04R 25/554 using a wireless connection, e.g. between microphone and amplifier or using Tcoils
• CPC Class Codes: H04R 25/558 Remote control, e.g. of amplification, frequency
• CPC Class Codes: H04R 25/652 Ear tips; Ear moulds hybrid ear moulds or post-processing thereof for their customisation H04R25/659
• CPC Class Codes: H04R 3/02 for preventing acoustic reaction , i.e. acoustic oscillatory feedback specially adapted for hearing aids H04R25/453

Abstract

According to various embodiment of a method of operating a hearing instrument, an acoustic signal pathway is provided from a microphone through a signal processor to a hearing instrument (HI) receiver in an acoustic mode of operation. An RF transmit signal pathway is provided from the microphone to an RF transmitter, and an RF receive signal pathway is provided from the RF receiver through the signal processor to the HI receiver in an RF mode of operation. An input signal representative of sound detected by the microphone is adaptively filtered. A first adaptation rate is used for the acoustic mode of operation and a second adaptation rate is used for the RF mode of operation. The second adaptation rate is faster than the first adaptation rate.

Claims

1. A hearing assistance device, comprising:

a housing configured to be worn on or in an ear of a wearer;

a microphone in the housing;

an output from the housing;

a receiver connected to the output;

an adaptive filter in the housing configured to perform acoustic feedback cancellation for the hearing assistance device;

a signal processor in the housing programmed to include feedback cancellation; and

a wireless communication antenna in the housing, a wireless communication receiver in the housing, and a wireless communication transmitter in the housing;

wherein the hearing assistance device is configured to operate in multiple reception modes including a wireless communication mode;

wherein in the wireless communication mode, the microphone is electrically decoupled from the output and a received wireless signal is used as a training signal for the adaptive filter, wherein the signal processor is configured to modify the feedback cancellation by changing an adaptation coefficient of the adaptive filter such that echo cancellation of the wireless signal is performed by the adaptive filter.

2. The hearing assistance device of claim 1, wherein the signal processor is configured to provide a first adaptation rate for the adaptive filter to perform acoustic feedback cancellation and a second adaptation rate for the adaptive filter to perform echo cancellation, wherein the first adaptation rate is different than the second adaptation rate.

3. The hearing assistance device of claim 1, wherein the adaptation coefficient is set using a sample rate of received wireless signal.

4. The hearing assistance device of claim 1, wherein the adaptation coefficient is configured to be adapted using a recursive least square error (RLS) method.

5. The hearing assistance device of claim 1, wherein the adaptation coefficient is configured to be adapted using a least mean squared error (LMS) method.

6. The hearing assistance device of claim 1, wherein a reception mode includes an acoustic mode, and wherein in the acoustic mode, the signal processor processes a signal representative of a sound detected by the microphone into a processed signal, and the receiver outputs an audio signal representative of the processed signal.

7. The hearing assistance device of claim 1, wherein the echo cancellation includes the use of finite impulse response (FIR) filters.

8. The hearing assistance device of claim 1, wherein the hearing assistance device is configured such that a wearer of the hearing assistance device is limited to hearing only wireless input in wireless communication mode.

9. The hearing assistance device of claim 8, wherein the hearing assistance device is configured such that the wearer hears the wireless input in one ear and an acoustic sidetone of the wearer in the other ear.

10. The hearing assistance device of claim 1, further comprising a voice activity detector (VAD) configured to enable the adaptive filter when a voice is detected.

11. The hearing assistance device of claim 1, wherein the hearing assistance device includes a hearing aid.

12. The hearing assistance device of claim 1, wherein the signal processor is configured to automatically switch reception modes of the hearing assistance device upon reception of a radio frequency signal of programmable strength.

13. The hearing assistance device of claim 12, wherein switching reception modes includes switching from the wireless communication mode to an acoustic mode.

14. The hearing assistance device of claim 12, wherein switching reception modes includes switching from an acoustic mode to the wireless communication mode.

15. The hearing assistance device of claim 1, wherein reception modes are configured to be switched by the wearer using a manual switch on the housing.

16. The hearing assistance device of claim 1, wherein the signal processor is programmed to provide a mode specific adjuster adapted to adjust signal pathways when switching between reception modes, wherein for the wireless communication mode, the mode specific adjuster provides a wireless receive signal path from a wireless communication receiver to the signal processor, and wireless communication transmit signal path from the microphone to a wireless transmitter, wherein the adaptive filter is configured to operate with a first adaptation rate for the acoustic mode and with a second adaptation rate for the wireless communication mode, wherein the first adaptation rate is slower than the second adaptation rate, and wherein for the acoustic mode, the mode specific adjuster provides an acoustic signal path from the microphone to the signal processor.

17. The hearing assistance device of claim 16, wherein the mode specific adjuster is adapted to change the adaptation coefficient when switching between acoustic and wireless communication modes of operation.

18. The hearing assistance device of claim 16, wherein, for the acoustic mode of operation, the signal processor is configured to perform an anti-correlation function between input and output signals for the signal processor.

19. The hearing assistance device of claim 16, wherein, for the wireless communication mode of operation, the signal processor is configured to perform an anti-correlation function between a receive signal on a wireless communication receive signal pathway and a transmit signal on the wireless communication transmit signal pathway.

20. The hearing assistance device of claim 1, wherein, in the wireless communication mode of operation, the signal processor is configured to enable adaptive filtering when a voice is detected.