METHOD FOR OPERATING A HEARING DEVICE

Abstract

A method for operating a hearing device. In this method, an entire audio signal is detected by means of a microphone. The entire audio signal is divided into a first audio signal and a second audio signal. A speech intelligibility of the second audio signal is reduced. The first audio signal and the second audio signal are combined to form an output signal, and the output signal is output by means of an output device. Further, a hearing device is provided.

Claims

1. A method for operating a hearing device, the method comprising: detecting an entire audio signal via a microphone; dividing the entire audio signal into a first audio signal and a second audio signal; reducing a speech intelligibility of the second audio signal; combining the first audio signal and the second audio signal to form an output signal; and outputting the output signal via an output device.

2. The method according to claim 1, wherein the entire audio signal is divided into the first and second audio signals by a directional microphone.

3. The method according to claim 1, wherein, to reduce speech intelligibility, the second audio signal is filtered using a low-pass filter.

4. The method according to claim 1, wherein a spectral resolution and/or dynamic range of the second audio signal are reduced in order to reduce speech intelligibility.

5. The method according to claim 1, wherein a reverberation is added to reduce speech intelligibility.

6. The method according to claim 5, wherein a frequency response and/or a reverberation time of the reverberation are changed.

7. The method according to claim 1, wherein the manner and/or extent of the speech intelligibility reduction are performed depending on a current listening situation.

8. The method according to claim 1, wherein a speech intelligibility of the first audio signal is increased.

9. A hearing device comprising: a microphone; an output device; and a signal processing unit,; wherein the hearing device is operated according to the method according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0036] FIG. 1 schematically shows a hearing device;

[0037] FIG. 2 shows a method for operating the hearing device;

[0038] FIG. 3 shows in simplified form a frequency spectrum of a second audio signal; and

[0039] FIG. 4 shows in simplified form a time profile of a portion of the second audio signal.

DETAILED DESCRIPTION

[0040] In FIG. 1, a hearing device 2 is shown in the form of a hearing aid, which is provided and designed to be worn behind an ear of a user (hearing device wearer, wearer). In other words, this is a behind-the-ear hearing aid. Hearing device 2 comprises a housing 4, which is made of a plastic. A microphone 6 with two microphone units 8, each in the form of an electromechanical transducer, is arranged within housing 4 and is designed to be omnidirectional. By changing a time offset between the acoustic signals detected by means of the omnidirectional microphone units 8, it is possible to change a directional characteristic of microphone 6 so that a directional microphone is realized. The two microphone units 8 are signal-coupled to a signal processing unit 10 which comprises an amplifier circuit and a signal processor. Signal processing unit 10 is further formed by circuit elements, such as, for example, electrical and/or electronic components. The signal processor is a digital signal processor (DSP) and is signal-connected to microphone units 8 via an A/D converter.

[0041] An output device 12 in the form of a receiver is signal-coupled to signal processing unit 10. During operation, an (electrical) signal provided by signal processing unit 10 is converted into an output sound 14, therefore, into sound waves, by means of output device 12, which is thus an electromechanical acoustic transducer. These are fed into a sound tube 16 one end of which is attached to housing 4. The other end of sound tube 16 is enclosed by a dome 18 which, in the intended state, is placed in an ear canal of the user, therefore, the wearer of hearing device 2. Here, dome 18 has multiple openings so that wearing comfort is increased. Power is supplied to signal processing unit 10, microphone 6, and output device 12 by means of a battery 20 located in housing 4.

[0042] FIG. 2 shows a method 22 for operating hearing device 2, which is carried out in part by signal processing unit 10. Thus, hearing device 2 is operated in accordance with method 22. In a first work step 24, an ambient sound 26 is detected by microphone 6, therefore, by each of microphone units 8. Ambient sound 26 has a first sound 28 (sound component) that originates from a sound source located in front of the wearer of hearing device 2. In the example shown, first sound 28 is emitted by a conversation partner of the wearer of hearing device 2 and comprises human speech. Further, ambient sound 26 comprises a second sound 30 emitted from an interference source in the opinion of the wearer of hearing device 2. In the example, these are conversations of other people whom the wearer of hearing device 2 does not want to follow, however.

[0043] By means of each of the microphone units 8, an electrical signal is created based on the ambient sound 26 detected in each case, each of which comprises components corresponding to the first and second sounds 28, 30, and which together represent an entire audio signal 32. In other words, the entire audio signal 32 corresponding to ambient sound 26 is detected by microphone 6. The entire audio signal 32 is subsequently routed to signal processing unit 10. The entire audio signal 32 is analyzed by signal processing unit 10 and an actual listening situation 34 is derived therefrom. Because there are multiple components that correspond to conversations of people in the entire audio signal 32, the current listening situation 34 in this example is assumed to be in a room with multiple people speaking.

[0044] In a subsequent second work step 36, the entire audio signal 32 is divided into a first audio signal 38 and a second audio signal 40. For this purpose, the two electrical signals created by microphone units 8 are added to one another with a certain time offset, so that a directional microphone is realized by means of microphone 6. Here, first audio signal 38 corresponds to an area which is located in front of hearing device 2 and is in particular a cardioid. Thus, first audio signal 38 substantially corresponds to first sound 28. For this purpose, the time offset is selected accordingly.

[0045] Second audio signal 40 corresponds to the opposite, and the combining of the electrical signals produced by the two microphone units 8 is carried out in the opposite manner, so that second audio signal 40 essentially contains second sound 30. Consequently, second audio signal 40 includes all sound sources located in an anti-cardioid behind hearing device 2 if the wearer of hearing device 2 is looking straight ahead. In summary, the dividing of the entire audio signal 32 into the two audio signals 38, 40 is carried out by means of the corresponding combining of the electrical signals detected by the two microphone units 8, so that a directional microphone is realized by means of microphone 6. In other words, the entire audio signal 32 is divided into the two audio signals 38, 40 by means of the directional microphone.

[0046] In a subsequent third work step 42, a speech intelligibility of first audio signal 38 is increased. For this purpose, a reverberation of first audio signal 38 is reduced and high frequencies are boosted and thus amplified. In particular, frequencies above a frequency of 100 Hz are amplified hereby, whereas lower frequencies are attenuated. Also, first audio signal 38 is adjusted according to a set of parameters stored in signal processing unit 10. The parameter set depends on a hearing loss of the wearer of hearing device 2 and was set by an audiologist or by means of another method.

[0047] In a fourth work step 44, performed substantially concurrently with the third work step 42, a speech intelligibility of second audio signal 40 is reduced. For this purpose, second audio signal 40 is filtered by means of a low-pass filter which is a component of signal processing unit 10, so that subsequently the frequency spectrum of second audio signal 40 shown in FIG. 3 has only frequencies which are below a cutoff frequency 46 which is operated at 100 Hz. The original second audio signal 40 is shown as a dotted line in FIG. 3. In addition, a spectral resolution of the remaining portion of second audio signal 40 is reduced, so that it has only five different frequencies/frequency bands in the example shown. In addition, a dynamic range of second audio signal 40 is reduced so that a distance between the minima and maxima of the amplitudes of the different frequency bands is limited. Furthermore, individual frequencies/frequency bands, in the example shown the second highest, are excessively attenuated so that a frequency selective amplification occurs. Subsequently, the frequency spectrum of second audio signal 40 has the shape shown by the solid line in FIG. 3.

[0048] A fifth work step 48 is then carried out. In this step, a reverberation 50 shown in FIG. 4 is added to the (processed) second audio signal 40. For this purpose, second audio signal 40 is again mapped onto itself after a reverberation time 52, wherein a frequency response 54 is adjusted. This is achieved by means of an appropriate convolution performed by signal processing unit 10. Here, frequency response 54 and reverberation time 52 of reverberation 50 are changed randomly. As a result of the processing in the fourth and fifth work steps 44, 48, the fragments of conversation originally contained in second sound 30 are no longer intelligible in second audio signal 40 processed in this way, but are merely present in an indistinct or washed-out form.

[0049] In a subsequent sixth work step 56, first audio signal 38 and second audio signal 40, therefore, the processed audio signals 38, 40, are combined to form an output signal 58. For this purpose, first audio signal 38, as it is present after third work step 42 is performed, is added to second audio signal 40, attenuated by half, as it is present after fifth work step 48, and this result is used as output signal 58.

[0050] In a subsequent seventh work step 60, output signal 58 is applied to output device 12 and thus output by it. As a result, output sound 14 is created and introduced into sound tube 16. Output sound 14 contains first sound 28 adapted to the hearing loss or components corresponding thereto. In addition, output sound 14 contains second sound 30, wherein, however, the speech intelligibility has been reduced. Thus, it is easier for the wearer of hearing device 2 to follow the desired conversation corresponding to first sound 28.

[0051] If a different current listening situation 34 was determined in first work step 24, the speech intelligibility of second audio signal 40 is reduced in a different manner and to a different extent in fourth work step 44 and fifth work step 48. For example, if it has been determined that the wearer is in a forest or in a quiet environment, wherein the first and second sounds 28, 30 are present, wherein no human voice is present in second sound 30, the speech intelligibility of second audio signal 40 is not reduced or is reduced only relatively slightly. Thus, for example, reverberation 50 is not added, and the spectral resolution is also not reduced. Thus, a loss of information for the wearer of hearing device 2 is reduced.

[0052] The invention is not limited to the exemplary embodiment described above. Rather, other variants of the invention can also be derived herefrom by the skilled artisan, without going beyond the subject matter of the invention. Particularly, further all individual features described in relation to the exemplary embodiment can also be combined with one another in a different manner, without going beyond the subject matter of the invention.

[0053] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.