Traitement en cours

Veuillez attendre...

Paramétrages

Paramétrages

Aller à Demande

1. WO2007099115 - PROCEDE ET SYSTEME PERMETTANT DE REDUIRE LE BRUIT DANS UN DISPOSITIF D'AIDE AUDITIVE

Note: Texte fondé sur des processus automatiques de reconnaissance optique de caractères. Seule la version PDF a une valeur juridique

[ EN ]

CLAIMS

1. A hearing aid comprising at least one microphone, a signal processing means and an output transducer, wherein said signal processing means is adapted to receive an input signal from the microphone, wherein said signal processing means is adapted to apply a hearing aid gain to said input signal to produce an output signal to be output by said output transducer, and wherein said signal processing means further comprises means for adjusting said hearing aid gain according to direct transmission gain calculated for the hearing aid.

2. The hearing aid according to claim 1 , wherein said means for adjusting said hearing aid gain comprises means for applying dynamic noise reduction techniques.

3. The method according to claim 2, wherein said means for adjusting said hearing aid gain are adapted to improve speech intelligibility in noise of said output signal.

4. The hearing aid according to claim 3, wherein said means for adjusting said hearing aid gain further comprises means for optimizing a speech intelligibility index.

5. The hearing aid according to claim 4, wherein said means for adjusting said hearing aid gain is adapted to optimize said speech intelligibility index to produce a set of frequency dependent speech intelligibility index gain values for each time sample of said input signal.

6. The hearing aid according to one of the preceding claims, wherein said means for adjusting said hearing aid gain is adapted to adjust said hearing aid gain to a value not below said direct transmission gain.

7. The hearing aid according to one of the preceding claims, wherein said means for adjusting said hearing aid gain provides a safety margin k and is adapted to adjust said hearing aid gain to a value not below said direct transmission gain plus said safety margin.

8. The hearing aid according to one of claims 3 to 7, wherein said means for calculating a speech intelligibility index is adapted to calculate a speech intelligibility index gain as a function of a plurality of input parameters.

9. The hearing aid according to claim 8, wherein said input parameters comprises at least one of a frequency dependent hearing threshold level, an estimated noise level, and an estimated speech level.

10. The hearing aid according to claim 3 or 9, wherein said means for adjusting said hearing aid gain is adapted to calculate a noise reducing hearing aid gain from an initial hearing aid gain and said optimized speech intelligibility index gain, and to adjust said noise reducing hearing aid gain to a value not below a threshold level.

11. The hearing aid according to claim 10, wherein said threshold level is the level of said direct transmission gain.

12. The hearing aid according to claim 10, wherein said threshold level is the level of said direct transmission gain plus a safety margin.

13. The hearing aid according to one of claims 10 to 12, wherein said means for adjusting said hearing aid gain is adapted to detect the level of said noise reducing hearing aid gain before adjustment and, if said noise reducing hearing aid gain would be below said threshold level, to input said noise reducing hearing aid gain before adjustment as a further input parameter to said means for calculating a speech intelligibility index.

14. The hearing aid according to one of claims 7 to 13, wherein said safety margin is a gain value in the range of 0 to 15 dB, preferably in the range of 5 to 15 dB.

15. The hearing aid according to one of claims 7 to 13, wherein said safety margin is a gain value of 5 to 8 dB, preferably 7 to 8 dB.

16. The hearing aid according to one of the preceding claims, further comprising a band-split filter for converting said input signal into band-split input signals of a plurality of frequency bands and wherein said hearing aid is further adapted to process said band-split input signals in each of said frequency bands
independently.

17. A method of reducing noise in a hearing aid comprising at least one microphone producing an input signal, a signal processing means producing an output signal from said input signal, and an output transducer outputting said output signal, wherein said method comprises:
- storing a direct transmission gain calculated for said hearing aid and its user in a memory of said hearing aid; and
- applying a hearing aid gain to said input signal to produce said output
signal, wherein said hearing aid gain is adjusted by said direct transmission gain so that said hearing aid gain is not set to a value below said direct
transmission gain.

18. The method according to claim 17, wherein said step of adjusting said hearing aid gain comprises the step of applying dynamic noise reduction techniques.

19. The method according to claim 18, wherein said step of adjusting said hearing aid gain comprises improving speech intelligibility in noise of said output signal.

20. The method according to claim 19, wherein said step of adjusting said hearing aid gain further comprises a step of optimizing a speech intelligibility index.

21. The method according to one of claims 17 to 20, wherein said step of adjusting said hearing aid gain comprises calculating a speech intelligibility index gain reducing the noise in said output signal and adjusting said hearing aid gain by said speech intelligibility index gain.

22. The method according to one of claims 17 to 20, wherein said step of adjusting said hearing aid gain comprises optimizing said speech intelligibility index to produce a set of frequency dependent speech intelligibility index gain values for each time sample of said input signal.

23. The method according to one of claims 20 to 22, wherein said speech intelligibility index gain is calculated with said direct transmission gain as a constraint to ensure that said hearing aid gain is not set to a value below said direct transmission gain.

24. The method according to one of claims 17 to 23, wherein said hearing aid gain is not set to a value below said direct transmission gain plus a safety margin k.

25. The method according to one of claims 21 to 24, further comprising the step of converting said input signal into band-split input signals of a plurality of frequency bands and wherein said method is further carried out for each of said frequency bands.

26. The method according to one of claims 21 to 24, wherein said speech intelligibility index gain comprises a set of frequency dependent gain values which are calculated simultaneously for an actual time sample of said frequency dependent input signal.

27. A system of reducing noise in a hearing aid comprising means for carrying out a method according to one of claims 17 to 26.

28.A computer program comprising executable program code which, when executed on a computer, executes a method according to one of claims 17 to

26.

29.A computer program product containing a computer readable medium with executable program code which, when executed on a computer, executes a method according to one of claims 17 to 26.