System and method for generating auditory spatial cues

• US 20070230729A1
• Filed: 11/06/2006
• Published: 10/04/2007
• Est. Priority Date: 03/28/2006
• Status: Active Grant

• Current Assignee: Oticon A/S (William Demant Fonden)
• Original Assignee: Oticon A/S (William Demant Fonden)
• Inventors: Naylor, Graham, Weinrich, S. Gert
• Granted Patent: US 7,936,890 B2
• Time in Patent Office: Days
• US Class Current: 381/320
• CPC Class Codes: H04R 2420/07 Applications of wireless loudspeakers or wireless microphones
• CPC Class Codes: H04R 25/407 Circuits for combining signals of a plurality of transducers
• CPC Class Codes: H04S 2400/11 Positioning of individual sound objects, e.g. moving airplane, within a sound field H04S2420/13 takes precedence
• CPC Class Codes: H04S 2420/01 Enhancing the perception of the sound image or of the spatial distribution using head related transfer functions [HRTF's] or equivalents thereof, e.g. interaural time difference [ITD] or interaural level difference [ILD]

Abstract

This invention relates to a hearing aid system (100, 200, 300) for generating auditory spatial cues. The hearing aid system (100, 200, 300) comprises a first microphone unit (306) adapted to convert sound received at a first microphone (102) and received at a second microphone (104), a first delay unit (106) connected to the first microphone (102) delaying the signal from the first microphone (102), a first calculation unit (108) for summing the delayed signal of the first microphone (102) and signal of the second microphone (104), a processor unit (110) processing the summed signal, and a speaker converting the processed signal to a processed sound. The first and second microphones (102, 104) are separated by a predetermined first distance and the first delay unit (106) provides a predetermined first delay thereby generating a first auditory spatial cue representing a first spatial dimension in the summed signal.

Claims

1. A hearing aid system for generating auditory spatial cues and comprising a first microphone unit adapted to convert sound received at a first microphone to a first electric signal on a first output and received at a second microphone to a second electric signal on a second output, a first delay unit connected to said first output and adapted to delay said first electric signal, a first calculation unit connected to said first delay unit and said second output and adapted to sum said delayed first electric signal and said second electric signal and to generate a first summed signal, a processor unit connected to said first calculation unit and adapted to process said first summed signal and to generate a processed signal, and a speaker adapted to convert said processed signal to a processed sound, wherein said first and second microphone are separated by a predetermined first distance and said first delay unit provides a predetermined first delay thereby generating a first auditory spatial cue representing a first spatial dimension in said first summed signal.

2. A hearing aid system according to claim 1, wherein the microphone unit further comprises a third microphone for converting sound to a third electric signal on a third output, and wherein the third microphone is separated perpendicularly relative to an axis between the first and second microphones by a second predetermined distance.

3. A hearing aid system according to claim 2 further comprising a filter unit connecting to the third output and adapted to filter the third electric signal thereby generating a filtered third electric signal.

4. A hearing aid system according to claim 1 further comprising a second delay unit connecting to the first calculation unit and adapted to delay the first summed signal.

5. A hearing aid system according to claim 3 further comprising a second delay unit connecting to the filter unit and adapted to delay the filtered third electric signal.

6. A hearing aid system according to claim 2 further comprising a second delay unit connecting to the third microphone and adapted to delay the third electric signal.

7. A hearing aid system according to claim 3 further comprising a plurality of second delay unit connecting to the third microphone, the filter unit, and/or first calculation unit, and adapted to delay the third electric signal, the filtered third electric signal and/or the first summed signal.

8. A hearing aid system according to claim 5 further comprising a second calculation unit connecting to the second delay unit and the filter unit and adapted to sum the filtered third electric signal and time delayed first summed signal.

9. A hearing aid system according to claim 1 wherein the first calculation unit further is adapted to weight the delayed first electric signal and the second electric signal.

10. A hearing aid system according to claim 8, wherein, the second calculation unit further is adapted to weight the delayed filtered first summed signal and the filtered third electric signal.

11. A hearing aid system according to claim 2 further comprising a transceiver unit connecting to the first microphone unit and adapted to transmit the first, second and/or third electric signal of a first hearing aid to a transceiver unit of a second hearing aid, which comprises a second microphone unit separated from the first microphone unit by a third predetermined distance being perpendicular to the axis between the first and second microphone.

12. A hearing aid system according to claim 11, wherein the transceiver unit further is adapted to receive electric signals from said second microphone unit.

13. A hearing aid system according to claim 11, wherein the transceiver unit comprises a time delay unit adapted to delay the first, second, and/or third electric signal a predetermined time delay.

14. A hearing aid system according to claim 1 further comprising a body worn calculation device communicating with the transceivers of the first and second hearing aids and adapted to generate a first, second and/or third auditory spatial cues associated with spatial orientation of sound received at the first and second microphone unit.

15. A hearing aid system according to claim 14, wherein the body worn calculation device comprises a third microphone unit adapted to provide a further electric signal for generating a further auditory spatial cue.

16. A hearing aid system according to claim 1 further comprising a first filterbank connecting to the first microphone and adapted to generate a first series of frequency channel signals from the first electric signal and second filterbank connected to the second microphone and adapted to generate a second series of frequency channel signals from the second electric signal, and wherein the first delay unit is adapted to independently delay each of said first series of frequency channel signals and the first calculation unit is adapted to independently sum each of said delayed first series of frequency channel signals and said second series of frequency channel signals

17. A hearing aid system according to claim 1 further comprising A/D, D/A conversion units adapted to convert the microphone signals from analogue to digital domain and to convert the processed signal from digital to analogue domain.

18. A method for generating auditory cues and comprising generating a first electric signal defining a sound received at a first position, generating a second electric signal defining said sound received at a second position, delaying said first electric signal a predetermined first time delay thereby generating a delayed first electric signal, summing said delayed first electric signal and said second electric signal thereby generating a first summed signal having a first auditory cue representing a first spatial dimension, processing said first summed signal, and converting said processed signal to a processed sound.