Method for operating a hearing device and hearing device

Abstract

The present invention relates to a method for operating a hearing device (2), wherein the hearing device (2) has an ANC unit (18), wherein the ANC unit (18) has a feedforward unit (20) that outputs a feedforward signal (ff) to suppress external interference noise entering the ear canal (16) of the user of the hearing device (2) from the outside, wherein the ANC unit (18) has a feedback unit (22) that outputs a feedback signal (fb) to suppress internal interference noise present in the ear canal (16), wherein the hearing device (2) has a signal processing unit (24) having a settable gain (26) and amplifying the input signal (E1) of the hearing device (2) and outputting it as an amplified signal (S), wherein the feedback signal (fb) is used as a measure of the user's own voice, and the gain (26) of the signal processing unit (24) is set according to the feedback signal (fb) and therefore also according to the user's own voice.

Description

Technical Field

[0001] The invention relates to a method for operating a hearing device and a corresponding hearing device. Background Art

[0002] Hearing devices are used to output sound to a user of the hearing device. To this end, the user wears the hearing device on or in the ear. To output the sound, the hearing device has an earpiece and at least one microphone in order to receive the sound from the environment and then output it to the user. In this case, the hearing device additionally modifies the sound in order to compensate for the hearing loss of the user. Hearing devices are therefore also called hearing aids.

[0003] In addition, the hearing device can also perform active sound suppression, which is also called active noise cancellation, or ANC for short. With the help of ANC, sounds from the environment, in particular disturbing noises, are suppressed, so that a quiet listening environment is created for the user. ANC usually suppresses sounds that reach the user's ear canal from the external environment. However, the design of ANC can also be applied to sounds in the ear canal, which is called active occlusion reduction, or AOR for short. Accordingly, with the help of AOR, a quiet listening environment is also created, but here, in contrast to the aforementioned suppression of disturbing noises from the outside, the sounds that are just generated by the user himself or formed by standing waves in the ear canal are suppressed. This is especially the case when the ear canal is closed to the environment by an earplug. Therefore, AOR mainly refers to internal sound suppression that suppresses disturbing noises in the ear canal, while ANC usually refers to external sound suppression that suppresses disturbing noises outside the ear canal. Sometimes AOR is also summarized under the term ANC. In both cases, the actual sound suppression is carried out in the ear canal by generating an inverted signal, which is acoustically superimposed on the disturbing noise in the ear canal and then at least partially cancels the disturbing noise. Overall, in both cases disturbing noises, ie sounds that are usually perceived as disturbing by the user, are suppressed and a quiet listening environment is thereby created.

[0004] Active sound suppression in the context of hearing devices is described, for example, in EP 1 690 252 B1, EP 2 023 664 B1, DE 10 2008 015 264 A1, DE 10 2009 010 892 B4, EP 2 309 778 B1, EP 2 405 674 B1.

[0005] A common problem with hearing devices, especially hearing devices for closed supply, is the so-called occlusion effect. Due to the partial or complete occlusion of the ear canal when the hearing device is worn, standing waves can form in the ear canal during operation. The own voice of the user of the hearing device is then often perceived by the user himself as distorted, which is usually perceived as disturbing. AOR remedies this by reducing the occlusion effect. However, this is usually not sufficient to produce a natural timbre of the own voice. In addition, due to the gain of the hearing device itself, the own voice can sometimes also be distorted and accordingly sound unnatural. Summary of the invention

[0006] Against this background, the technical problem to be solved by the present invention is to provide an improved method for operating a hearing device. In particular, the method should improve the perception of the user of the hearing device of his own voice. In particular, the own voice should be processed in such a way that the user of the hearing device perceives his own voice as little interference as possible. Furthermore, a corresponding hearing device should be specified, which is suitable for carrying out the method.

[0007] According to the invention, the above technical problem is solved by a method having the features according to the invention and a hearing device having the features according to the invention. Advantageous embodiments, extensions and modifications are the content of the invention. The implementation in conjunction with the method also applies mutatis mutandis to the hearing device and vice versa. With regard to the method steps described below for the method, advantageous embodiments of the hearing device are produced in particular by the hearing device being designed to perform one or more of these method steps.

[0008] The method is used for operating a hearing device, in particular during normal use of the hearing device, ie when the hearing device is worn by a user for use. The hearing device has an ANC unit, wherein ANC is understood as active sound suppression, also known as "active noise cancellation".

[0009] The ANC unit has a feedforward unit, which outputs a feedforward signal to suppress external interference noise, which enters the ear canal of the hearing device user from the outside, especially through the earplug of the hearing device, in particular during normal use. In addition, the ANC unit has a feedback unit, which outputs a feedback signal to suppress internal interference noise present in the ear canal. Internal interference noise is especially standing waves in the ear canal caused by occlusion and the sound caused by the user himself, the so-called self-sound, which in particular also includes the user's own voice, which is transmitted into the ear canal as body sound, for example. The feedback unit is also called AOR unit because it effectively performs AOR, i.e. active occlusion reduction. The feedforward signal and the feedback signal are usually also respectively called correction signals. The two correction signals are especially electrical signals, which are fed to the earpiece of the hearing device and converted into sound by the earpiece. As a result, the sound is a so-called anti-sound, which completely or partially cancels, i.e. suppresses the interference noise when superposition occurs in the ear canal. Here, the sound suppression is purely acoustic, not at the electrical level.

[0010] Since the ANC unit has both a feedforward unit and a feedback unit, the ANC unit is also referred to as a hybrid ANC unit, which accordingly performs a hybrid ANC. In this case, interference noises of different origins are suppressed, i.e. internal interference noises are suppressed on the one hand and external interference noises are suppressed on the other hand. The feedback unit and the feedforward unit are operated in particular in parallel with one another and are preferably independent subunits of the ANC unit in each case. In particular, the feedforward unit and the feedback unit receive independent input signals and each output its own correction signal.

[0011] A hearing device is generally used to output sound to a user of the hearing device and is particularly preferably used to compensate for a hearing defect of a user, preferably a hearing-impaired user. In particular, the hearing device has for this purpose a signal processing unit with a settable gain, i.e. an amplification unit with a settable amplification factor. In this context, "setting / adjusting / reducing / increasing" the gain etc. means setting / adjusting / reducing / increasing the amplification factor etc. of the amplification unit.

[0012] Furthermore, the signal processing unit amplifies the input signal of the hearing device and outputs it as an amplified signal. The input signal is an electrical signal and is generated in particular by means of a microphone of the hearing device by converting sound from the environment. The gain is the same for all frequency ranges processed by the signal processing unit or is frequency-dependent and then different for different frequency ranges. The signal processing unit and its adjustable gain in the normal use of the hearing device in particular realize its actual hearing device function, namely the modification of the input signal in accordance with the individual hearing condition of the user, namely the audiogram. In operation, in particular, the hearing impairment of the user is thereby compensated.

[0013] The amplified signal and the two correction signals are output, in particular, via an earpiece of the hearing device. The earpiece converts the amplified signal and the two correction signals into sound. In particular, the correction signals have now been generated by the ANC unit so that the associated sound signal is destructively superimposed on the interfering noise in the ear canal, thereby suppressing the interfering noise.

[0014] The signal processing unit and the ANC unit are preferably part of a control unit of the hearing device. The control unit is also referred to as a controller and is for example a microcontroller or an ASIC or a combination thereof. The control unit is for example integrated into the housing of the hearing device and in normal use the user wears the housing on or in the ear, depending on the type of hearing device.

[0015] An important aspect here is that the feedback signal is used as a measure for the user's own voice and the gain of the signal processing unit is set as a function of the feedback signal and therefore also as a function of the user's own voice. In this way, the input signal is amplified, in particular, as a function of the feedback signal and also as a function of the user's own voice. Accordingly, a signal path is formed in the hearing device, which leads from the feedback unit to the signal processing unit and via which the feedback signal or a signal derived therefrom is fed to the signal processing unit so that the signal processing unit is controlled accordingly as a function of the feedback signal and the user's own voice. The feedback signal is therefore used, in particular, to identify the user's own voice and represents a quantitative and / or qualitative measure for the user's own voice (preferably also to be understood as meaning that such a measure is at least derived from the feedback signal). The gain of the signal processing unit and the noise suppression by the ANC unit are therefore usually linked to one another. The signal processing unit and the ANC unit are coupled to one another and are therefore advantageously synchronized, i.e. changes in the operation of the ANC unit are in particular also used directly to change the operation of the signal processing unit. The signal processing unit is therefore controlled indirectly or directly by the feedback unit so that the gain is set as a function of the feedback signal and therefore also as a function of the user's own voice. In addition, in a suitable embodiment, the gain is also set as a function of further signals or parameters, but this is of secondary importance here.

[0016] The mentioned setting of the gain according to the own voice recognized by the feedback signal is based in particular on the following considerations: on the one hand, due to the hybrid ANC in the ear canal, possible external interference noise has been completely or at least partially suppressed by the feedforward unit, and on the other hand, the sound is received in the ear canal for the feedback unit to perform AOR. Since the external interference noise is now suppressed, the internal interference noise is mainly or even only received in the ear canal. In the phase of one's own speech activity, that is, as long as the user speaks, his own voice is sent outward to the environment on the one hand, and then usually also included in the input signal, and on the other hand, it is transmitted to the ear canal as a body sound, and then appears there as an internal interference noise. At the same time, one's own voice can also enter the ear canal from the outside in principle, and then additionally exists as an external interference noise. Therefore, there are three paths to enter the ear canal for one's own voice in principle. Two of the paths are acoustic paths, that is, one from the outside and one from the inside to enter the ear canal. The third path is acoustic-electric mixing, that is, entering the signal processing from the outside through the microphone and then entering the ear canal through the earpiece.

[0017] Due to the suppression of external interference noise by the feedforward unit, it is assumed here that the own voice now constitutes a significant part of the internal interference noise that still remains, so that the feedback signal can be used to identify the own voice and in particular as a measure for the own voice, that is, in particular as a measure for the presence of the own voice (i.e., a quantitative measure) or even as a measure for the volume (i.e., level or amplitude) of the own voice (i.e., a qualitative measure). This measure is now actually also used to control the signal processing unit, so that the signal processing unit is therefore controlled according to the own voice, more precisely, the gain is set according to the own voice. Thus, it is advantageous to identify the own voice in a targeted and advantageous manner, and also in particular in time, in the phase of the own speech activity, and to adjust the processing of the input signal in the signal processing, and therefore also adjust the processing and final output of the own voice. Therefore, the own voice that reaches the ear canal as internal interference noise via the internal path is used to adjust the gain of the own voice in the third path of the acoustic-electrical. In this way, the processing of one's own voice can be improved, in particular with the aim of achieving a more natural perception of one's own voice, or at least outputting one's own voice in such a way that one's own voice is not considered to be interfering. To achieve this, in a preferred embodiment, the feedforward unit suppresses external interfering noise in the case of the user's own voice activity, so that the feedback signal mainly contains the user's own voice, and the gain is then set according to one's own voice. In general, in the phase of one's own voice activity, one's own voice is advantageously modified, in particular suppressed, in all three paths, namely in the acoustic path by means of the ANC unit and synchronously in the acoustic-electric path by means of the signal processing unit. Here, the feedback signal is used in particular as a measure for the user's voice activity.

[0018] In an advantageous embodiment, the feedback signal has an amplitude, and the gain decreases as the amplitude increases. Thus, in particular when one's own voice is loud, the input signal is amplified less, and therefore one's own voice in the input signal is also amplified less, so that the user may improve the perception of one's own voice. Therefore, the feedback signal is used in particular as a measure for one's own voice, so that the amplitude of the feedback signal describes the volume of one's own voice. This leads in particular to the ANC unit setting the gain differently depending on whether the user himself is speaking. In the phase of one's own voice activity, the amplitude is larger than in the phase without one's own voice activity, and the phase without one's own voice activity is, for example, when there are only other interfering noises, such as noise. Thus, in the phase of one's own voice activity, the gain is set lower than in the phase without one's own voice activity, and thus the volume of one's own voice in the input signal is targeted to be reduced in the phase of one's own voice activity, and a larger gain is set in the phase without one's own voice activity to achieve the best possible clarity of the sound from the environment.

[0019] As can be seen from the implementation to date, due to the suppression of external interfering noise by means of the feedforward signal, it is in principle possible to distinguish phases of own voice activity from the feedback signal, for example when the feedback signal exceeds a predefined threshold value. Therefore, in an advantageous embodiment, a distinction is made between phases of own voice activity and phases without own voice activity based on the feedback signal, preferably based on its amplitude, so that own voice detection is simultaneously performed with the aid of the ANC unit. The ANC unit is therefore used for own voice detection and in this respect advantageously also represents an OVD unit, i.e. an own voice detection unit, wherein OVD stands for "own voice detection". For example, an amplitude above a predefined threshold value is assumed to be a phase of own voice activity, and below the threshold value is similarly assumed to be a phase without own voice activity.

[0020] In principle, it is also conceivable to receive one's own voice, for example, by means of a spatial filter or a directional microphone, i.e. to receive the sound in a targeted manner from a certain direction, and then proceed from this point that the sound is one's own voice here according to the direction. In this regard, the own voice detection described here is a particularly simple alternative and is advantageous at least in this respect, because the ANC unit here fulfills a dual function, i.e. on the one hand, active sound suppression and on the other hand, own voice detection. A separate OVD unit is therefore unnecessary.

[0021] The ANC unit, in particular in its function as an OVD unit, is thereby advantageously used to set the gain so that the gain is reduced in phases of own voice activity and thereby the input signal and at least the own voice contained therein is attenuated. Furthermore, in an advantageous embodiment, the ANC unit is combined with the signal processing unit to form an OVP unit, wherein OVP stands for "own voice processing". On the one hand, the OVP unit recognizes the own voice based on the feedback signal of the feedback unit and, on the other hand, processes the own voice with the aid of the signal processing unit based on the feedback signal, since its gain is set based on the feedback signal. A separate OVP unit is then no longer required. Accordingly, the hearing device preferably does not have a separate OVP unit for own voice detection and processing.

[0022] In an advantageous embodiment, the gain is set in a frequency-dependent manner, i.e., the gain is set only in the frequency range in which the own voice is present. In this way, the own voice is modified in a targeted manner in the input signal, with the aim of outputting the own voice to the user as naturally as possible. In general, the frequency of the human voice lies approximately between 100 Hz and 10 kHz, but the actual frequency range of the own voice of a particular user is individual and is suitably determined using suitable measurements.

[0023] In a possible embodiment, the feedback unit has a working range which includes only frequencies up to a critical frequency, which is in particular predefined and stored, for example, in a memory of the hearing device. The critical frequency is preferably 1 kHz. Below this, the working range is in particular limited by the lower limit of the human hearing range, typically about 20 Hz. However, preferably also for frequencies above the critical frequency, the gain is set as a function of the feedback signal. These frequencies are in particular limited by the upper limit of the human hearing range, typically about 20 kHz. In other words, the control of the gain is not limited to these ranges which are also captured by the feedback unit. This is based on the consideration that speech is generally not limited to low frequencies, i.e. in particular frequencies up to 1 kHz. However, ANC units are usually designed only for such low frequencies, since most interfering noises are expected here, and in particular speech, mainly foreign voices, are not considered interfering noises in principle and do not necessarily need to be suppressed. However, in particular in the case of one's own voice, suppression is desirable for a more natural perception. Here, use is now made of the fact that in the operating range up to a certain critical frequency, in particular 1 kHz, the feedback unit also captures at least a portion of the own voice, so that the feedback signal can still be used as a sufficient measure for the presence of the own voice or for the volume of the own voice and can therefore be used for own voice detection. Here, of course, the critical frequency is selected in such a way that the operating range still includes at least a portion of the frequencies of the own voice. However, the suppression of the own voice is also advantageously carried out at frequencies that are included in the own voice but not included in the operating range of the feedback unit, in order to achieve the best possible processing of the own voice in the signal processing unit and in this way produce a more natural timbre of the own voice.

[0024] The hearing device has at least one microphone, with which an input signal is generated, in that the microphone receives sound from the environment and converts it into an electrical signal. The microphone is preferably an external microphone. The corresponding input signal is preferably fed to the signal processing unit and the feedforward unit, so that in a suitable embodiment, the hearing device has an external microphone, which generates the input signal, which is then fed to the feedforward unit to generate the feedforward signal. An "external" microphone is understood to be a microphone that is positioned in the normal use of the hearing device so that the microphone only receives or mainly receives sound from the environment of the user. For this purpose, the external microphone is usually directed outwards and is usually also positioned outside the ear canal of the user. Alternatively, the input signal for the feedforward unit is generated by means of a further, additional microphone of the hearing device, so that two input signals are generated, one for the signal processing unit and one for the feedforward unit. However, in any case, the microphone that generates the input signal for the feedforward unit is an external microphone, i.e. it is directed outwards relative to the user in order to correspondingly receive external interfering noise in the environment.

[0025] The feedback unit also receives an input signal generated by means of a microphone of the hearing device. However, the input signals for the feedforward unit and the feedback unit are different, since these units are to suppress different interfering noises, so that the microphones for the different input signals are positioned differently accordingly. In an advantageous embodiment, the input signal described above for the signal processing unit and possibly also for the feedforward unit is a first input signal, and the hearing device has an internal microphone, which generates a second input signal, which is fed to the feedback unit to generate a feedback signal. In contrast to an external microphone, an "internal" microphone is understood to be a microphone that is positioned in normal use of the hearing device such that the microphone receives only or predominantly sounds from the ear canal of the user. For this purpose, the internal microphone is usually oriented inwards and into the ear canal and / or is positioned in the ear canal of the user.

[0026] The difference between internal and external microphones therefore lies in particular in the arrangement relative to the ear canal of the user in normal use. The boundary between "inside" and "outside" is defined in particular by the earplug of the hearing device, which is placed in the ear canal in normal use and defines a volume in the ear canal, which is located inside and is bounded by the earplug, the ear canal wall and the eardrum. In contrast, the environment is located on the other side of the earplug, that is, outside. In both cases, the hearing device outputs sound inwardly, that is, into the ear canal, in that the earpiece is oriented inwardly into the ear canal for this purpose.

[0027] Preferably, the hearing device is designed for closed delivery and for this purpose has an earplug in order to close the ear canal during normal use of the hearing device. The earplug is, for example, a so-called dome or an ear mold. In a possible embodiment, the earplug has a so-called vent, i.e. a channel leading from the interior to the exterior, wherein the ear canal remains largely closed.

[0028] In a suitable embodiment, the modified signal, the feedback signal and the feedforward signal are combined with one another to form an output signal, which is then output via an earpiece of the hearing device. For example, the modified signal, the feedback signal and the feedforward signal are added to one another in a summator. The output signal then contains, on the one hand, the amplified signal output by the signal processing and, on the other hand, a correction signal for suppressing interfering noise.

[0029] Suitably, the output signal is amplified by an additional amplifier of the hearing device before being output through the earpiece. Thus, the modified signal, the feedback signal and the feedforward signal are subsequently amplified together, so to speak, in order to appropriately control the earpiece.

[0030] The hearing device according to the invention has a control unit which is designed to carry out the method described according to the invention. Suitable control units have already been mentioned above.

[0031] In particular, the above technical problem is also solved by a method for operating a hearing device, wherein the hearing device has an ANC unit, wherein the ANC unit has a feedforward unit, which outputs a feedforward signal to suppress external interfering noise entering the ear canal of a user of the hearing device from the outside, wherein the ANC unit has a feedback unit, which outputs a feedback signal to suppress internal interfering noise located in the ear canal, wherein the hearing device has a signal processing unit, which has an adjustable gain and which amplifies an input signal of the hearing device and outputs it as an amplified signal, wherein the feedback signal is used as a measure for the user's own voice, and the gain of the signal processing unit is set as a function of the feedback signal and thus also as a function of the own voice, wherein the gain of the signal processing unit is set as a function of the feedback signal, so that the input signal is amplified as a function of the feedback signal. The above description also applies analogously to the method, and advantageous embodiments, extensions and variants result from what has been described. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The embodiments of the present invention are explained in more detail below with reference to the accompanying drawings.

[0033] Figure 1 A hearing device is shown;

[0034] Figure 2 Shown in conventional use according to Figure 1 hearing devices. DETAILED DESCRIPTION

[0035] Figure 1 A hearing device 2 is shown, which has an earplug 4 , an earpiece 6 , an internal microphone 8 , at least one (here two) external microphones 10 , a housing 12 and a control unit 14 . Figure 2 The hearing device 2 and its circuit are shown in more detail in different views, but only one of the two external microphones 10 is shown. Figure 2 The ear canal 16 of the user of the hearing device 2 and three paths P1, P2, P3 through which the user's own voice can reach the ear canal 16 are shown. Figure 2 As shown, the user wears the hearing device 2 in or on the ear. For the type of hearing device shown here, the user wears the housing 12 on the ear, more precisely behind the ear, and wears the earplug 4 in the ear. The design described here can also be used for other types of hearing devices. Figure 1 and Figure 2 A method for operating a hearing device 2 is described, in particular in the case of regular use of the hearing device 2 . In this case, the control unit 14 is designed to carry out the method.

[0036] The hearing device 2 has an ANC unit 18, where ANC is understood to mean active sound suppression, also referred to as “active noise cancellation”. The ANC unit 18 has a feedforward unit 20, which outputs a feedforward signal ff to suppress external interference noise, which in particular enters the ear canal 16 from the outside, in particular through the earplug 4, via the external path P1 in normal use. In addition, the ANC unit 18 has a feedback unit 22, which outputs a feedback signal fb to suppress internal interference noise present in the ear canal 16. Internal interference noise is, for example, standing waves in the ear canal 16 caused by occlusion and sounds caused by the user himself, so-called self-sound, which in particular also includes the user's own voice, which is transmitted into the ear canal 16 as body sound via the internal path P2. The feedback unit 22 is also called an AOR unit, because it effectively performs AOR, i.e. active occlusion reduction. The feedforward signal ff and the feedback signal fb are usually also referred to as correction signals fb, ff, respectively. The two correction signals fb, ff are electrical signals, which are fed to the earpiece 6 and converted into sound by the earpiece. This sound is therefore a so-called counter-sound, which completely or partially cancels, ie suppresses, the interfering noise in the event of superposition in the auditory canal 16. The sound suppression takes place here purely acoustically and not on an electrical level.

[0037] Since the ANC unit 18 has both a feedforward unit 20 and a feedback unit 22, the ANC unit 18 is also referred to as a hybrid ANC unit 18, which accordingly performs a hybrid ANC. In this case, interference noises from different sources are suppressed, i.e. internal interference noises are suppressed on the one hand and external interference noises are suppressed on the other hand. Figure 2 As can be seen in FIG. 1 , the feedback unit 22 and the feedforward unit 20 operate in parallel with each other and are independent subunits of the ANC unit 18. In addition, the feedforward unit 20 and the feedback unit 22 receive independent input signals E1, E2 and output their own correction signals fb, ff, respectively.

[0038] The hearing device 2 is generally used to output sound to a user and in particular to compensate for the hearing defect of a user, here a hearing-impaired user. The hearing device 2 has a signal processing unit 24 with an adjustable gain, i.e. an amplifier unit with an adjustable amplification factor. The signal processing unit 24 amplifies an input signal E1 of the hearing device 2 and outputs it as an amplified signal S. The input signal E1 is an electrical signal and is generated by means of at least one external microphone 10. The signal processing unit 24 and its adjustable gain 26 realize the actual hearing device function of the hearing device 2 in normal use, i.e. the modification of the input signal E1 according to the individual hearing condition of the user, i.e. the audiogram.

[0039] The amplified signal S and the two correction signals fb, ff are outputted via the earpiece 6. Here, the earpiece 6 converts the amplified signal S and the two correction signals fb, ff into sound. The correction signals fb, ff have been generated by the ANC unit so that the associated sound signal is destructively superimposed on the interference noise in the ear canal 16, thereby suppressing the interference noise.

[0040] In the embodiment shown, the signal processing unit 24 and the ANC unit 18 are part of the control unit 14 of the hearing device 2. Here, the control unit 14 is integrated into the housing 12 which, in normal use, is worn on or in the ear by the user, depending on the type of hearing device.

[0041] In this case, the feedback signal fb is used as a measure for the user's own voice, and the gain 26 of the signal processing unit 24 is set as a function of the feedback signal fb and thus also as a function of the user's own voice, so that the input signal E1 is amplified also as a function of the feedback signal fb and also as a function of the user's own voice. Accordingly, a signal path 28 is formed in the hearing device 2, which leads from the feedback unit 22 to the signal processing unit 28 and is Figure 2 The feedback signal fb is fed directly to the signal processing unit 24 via this signal path or, in an alternative not shown, a signal derived therefrom is fed to the signal processing unit 24 so that the signal processing unit is controlled accordingly as a function of the feedback signal fb. The gain 26 and the noise suppression by the ANC unit 18 are thus coupled to one another and are therefore synchronized, i.e. a change in the operation of the ANC unit 18 is also used to change the operation of the signal processing unit 24. The feedback unit 22 thus controls the signal processing unit 24 indirectly or directly so that the gain 26 is set as a function of the feedback signal fb.

[0042] The mentioned setting of the gain 26 as a function of the feedback signal fb is based on the following considerations: on the one hand, due to the hybrid ANC in the ear canal 16, possible external interfering noise has already been completely or at least partially suppressed by the feedforward unit 20, and on the other hand, sound is received in the ear canal 16 for the feedback unit 22 to perform AOR. Since the external interfering noise has now been suppressed, mainly or even only internal interfering noise is received in the ear canal 16. In the phase of own speech activity, i.e. as long as the user himself speaks, his own voice is, on the one hand, sent outward to the environment and is then usually also included in the input signal E1, and on the other hand is transmitted as body sound into the ear canal 16 and then appears there as internal interfering noise. At the same time, the own voice can also enter the ear canal 16 from the outside and then additionally exist as external interfering noise. Therefore, in principle there are three paths P1, P2, P3 for the own voice to enter the ear canal 16, as shown in Figure 2Two of the paths P1, P2, and P3 are acoustic paths P1 and P2, namely, one from the outside and one from the inside into the ear canal 16. The third path P3 is an acoustic-electric hybrid, namely, from the outside into the signal processing unit 24 through the microphone 10 and then into the ear canal 16 through the earpiece 6.

[0043] Figure 2 , an external signal Ext, such as one's own voice and / or one or more other environmental noises, and additional noise N are shown as external interfering noises. The external signal Ext and the noise N are sounds that reach the ear canal 16 via the external path P1 through the earplug 4 and / or via the path P3 via the signal processing unit 24.

[0044] Due to the suppression of external interfering noise by the feedforward unit 20, it is assumed here that the own voice now constitutes the main part of the still remaining internal interfering noise, so that the feedback signal fb can be used as a measure for the own voice, or even as a measure for the volume (that is: level or amplitude) of the own voice. This measure is now actually also used to control the signal processing unit 24, so that the signal processing unit is therefore controlled according to the own voice, more precisely, the gain 26 is set according to the own voice. As a result, the processing of the input signal E1 is adjusted in the signal processing unit 24 in a targeted and timely manner in the phase of the own voice activity, and thus also the processing and final output of the own voice. Therefore, the own voice that reaches the ear canal 16 as internal interfering noise via the internal path P2 is used to adjust the gain 26 of the own voice in the third path P3 of the acoustic and electrical. In this way, the processing of the own voice can be improved, and the purpose here is in particular to achieve a more natural perception of the own voice, or at least to output the own voice in such a way that the own voice is not considered to be interfering. To achieve this, the feedforward unit 20 suppresses external interfering noises in the case of the user's own voice activity, so that the feedback signal fb mainly contains the user's own voice, so that the gain 26 is then set according to the own voice. Overall, the own voice is suppressed in all three paths P1, P2, P3, that is, in the acoustic path P1, P2 by means of the ANC unit 18 and synchronously in the acoustic-electric path P3 by means of the signal processing unit 24 during the phase of the own voice activity.

[0045] The feedback signal fb has an amplitude, and the gain 26 decreases as the amplitude increases. Thus, when the own voice is loud, the input signal E1 is amplified less, and therefore the own voice in the input signal E1 is also amplified less, so that the user's perception of the own voice may be improved. This results in the ANC unit 18 setting the gain 26 differently depending on whether the user himself is speaking. In the phase of one's own voice activity, the amplitude is larger than in the phase without one's own voice activity, for example, when there are only other interfering noises, such as noise N. Thus, in the phase of one's own voice activity, the gain 26 is set lower than in the phase without one's own voice activity, and thus the volume of one's own voice in the input signal E1 is targeted to be reduced in the phase of one's own voice activity, and a larger gain 26 is set in the phase without one's own voice activity to achieve the best possible clarity of the sound from the environment.

[0046] As can be seen from the implementation to date, due to the suppression of external interfering noise by means of the feedforward signal ff, it is in principle possible to distinguish phases of own voice activity on the basis of the feedback signal fb, for example when the feedback signal fb exceeds a predefined threshold value. In the exemplary embodiment shown, phases of own voice activity and phases without own voice activity are therefore distinguished on the basis of the feedback signal fb, more precisely on the basis of its amplitude, so that own voice detection is simultaneously performed with the aid of the ANC unit 18. The ANC unit 18 is therefore used for own voice detection and in this respect also represents an OVD unit, i.e. an own voice detection unit, where OVD stands for "own voice detection". In this case, phases of own voice activity are assumed when the amplitude is above a predefined threshold value, and phases without own voice activity are similarly assumed when the amplitude is below the threshold value.

[0047] In principle, it is also conceivable to receive one's own voice, for example, by means of a spatial filter or a directional microphone, i.e. to receive the sound from a specific direction in a targeted manner, and then from this point of view, the sound is one's own voice here according to the direction. In this regard, the own voice detection described here is an alternative. According to the solution described here, the ANC unit 18 here can be said to fulfill a dual function, i.e. on the one hand, active sound suppression and on the other hand, own voice detection. Therefore, a separate OVD unit is not necessary and is not present in the illustrated embodiment.

[0048] The ANC unit 18, in particular in its function as an OVD unit, is thus used to set the gain 26 in order to reduce the gain in phases of own voice activity and thereby attenuate the input signal E1 and at least the own voice contained therein. Furthermore, in the illustrated embodiment, the ANC unit 18 is combined with the signal processing unit 24 to form an OVP unit, which is not explicitly indicated, wherein OVP stands for "own voice processing". On the one hand, the OVP unit recognizes the own voice based on the feedback signal fb of the feedback unit 22 and, on the other hand, processes the own voice based on the feedback signal with the aid of the signal processing unit 24, since its gain 26 is set based on the feedback signal fb. A separate OVP unit is then no longer necessary and is not present in the illustrated embodiment.

[0049] Optionally, the gain 26 is set frequency-dependently, ie, the gain is set only in the frequency range in which the own voice is present. In this way, the own voice is modified in a targeted manner in the input signal E1, with the aim of outputting the own voice to the user as naturally as possible.

[0050] In an alternative embodiment, the feedback unit 22 has a working range which includes only frequencies up to a critical frequency, which is in particular predefined and stored, for example, in a memory of the hearing device 2, not explicitly shown. The critical frequency is, for example, 1 kHz. For frequencies above the critical frequency, the gain 26 is also set as a function of the feedback signal fb. In other words, the control of the gain 26 is not limited to these ranges, which are also captured by the feedback unit 22. This is based on the consideration that speech is generally not limited to low frequencies. However, the ANC unit 18 is usually designed only for such low frequencies, since most interfering noise is expected here, and in particular speech, mainly foreign voices, are not considered interfering noise in principle and do not necessarily need to be suppressed. However, in the case of one's own voice, suppression is desirable for a more natural perception. Here, use is made of the fact that in the working range up to a certain critical frequency, for example 1 kHz, the feedback unit 22 also captures at least a part of one's own voice, so that the feedback signal fb can still be used as a sufficient measure for the presence of one's own voice, or a sufficient measure for the volume of one's own voice, and can therefore be used for own voice detection. However, the suppression of one's own voice also takes place at frequencies which are included in one's own voice but not in the operating range of the feedback unit 22, so as to achieve the best possible processing of one's own voice in the signal processing unit 24 and in this way produce a more natural timbre of one's own voice.

[0051] As already explained, the hearing device 2 has at least one microphone 10, with which an input signal E1 is generated. The microphone 10 is an external microphone here. In the exemplary embodiment shown, the corresponding input signal E1 is fed to the signal processing unit 24 and the feedforward unit 20. An “external” microphone 10 is understood to be a microphone 10 which, in normal use of the hearing device 2, is positioned such that the microphone 10 receives only or predominantly sounds from the user's environment. For this purpose, the external microphone 10 is usually oriented outwards and is usually also, for example, Figure 2 In an alternative not shown, the input signal E1 for the feedforward unit 20 is generated by means of a further, additional microphone of the hearing device 2, so that two input signals E1 are generated, one for the signal processing unit 24 and one for the feedforward unit 20.

[0052] The feedback unit 22 also receives an input signal E2 generated by means of the microphone 8 of the hearing device 2. However, the input signals E1, E2 for the feedforward unit 20 and the feedback unit 22 are different, since these units are to suppress different interfering noises, so that the microphones 8, 10 are positioned differently accordingly. The input signal E1 described above for the signal processing unit 24 and the feedforward unit 20 is then also referred to as the first input signal E1. The internal microphone 8 then generates a second input signal E2, which is fed to the feedback unit 22 to generate the feedback signal fb. In contrast to the external microphone 10, the "internal" microphone 8 is understood to be a microphone that, in conventional use of the hearing device 2, is, for example, Figure 2 The microphone is positioned as shown in , so that the microphone 8 receives only or primarily sounds from the user's ear canal 16. To this end, the internal microphone 8 is generally oriented inwardly and into the ear canal 16 and / or positioned within the user's ear canal 16.

[0053] Here, the boundary between "inside" and "outside" is defined by the earplug 4 of the hearing device 2, which is placed in the ear canal 16 during normal use and defines a volume within the ear canal, which is located inside and is bounded by the earplug 4, the ear canal wall and the eardrum. Figure 2 In FIG. 4 , this volume is shown as an auditory canal 16 . In contrast, the environment is located on the other side of the earplug 4 , ie, outside. In both cases, the hearing device 2 outputs sound inwardly, ie, into the auditory canal 16 .

[0054] Despite Figure 2 In the illustration of , the dotted frame representing the hearing device 2 overlaps the ear canal 16 , but the ear canal 16 is of course not a part of the hearing device 2 . Figure 2 The overlap in the figure is only a result of simplified illustration.

[0055] The hearing device 2 shown here is designed for closed delivery and for this purpose has an earplug 4 to close the auditory canal 16 during normal use of the hearing device 2. The earplug 4 is, for example, a so-called dome or ear mold. In a possible embodiment that is not shown in detail here, the earplug 4 also has a so-called vent.

[0056] In the embodiment shown, the modified signal (i.e. amplified signal) S, the feedback signal fb and the feedforward signal ff are combined with one another to form an output signal A, which is then output via the earpiece 6. In this case, the modified signal S, the feedback signal fb and the feedforward signal ff are added to one another in a summer 30. The output signal A then contains, on the one hand, the amplified signal S output by the signal processing unit 24 and, on the other hand, the correction signals fb, ff for suppressing interfering noise. In addition, the output signal A is amplified by means of an additional amplifier 32 of the hearing device 2 before the output signal A is output via the earpiece 6. Thus, the modified signal S, the feedback signal fb and the feedforward signal ff are, so to speak, subsequently amplified together. The summer 30 and the additional amplifier 32 are not essential and are essentially independent of the basic concept of controlling the signal processing unit 24 as a function of the feedback signal fb.

[0057] Reference numerals list

[0058] 2 Hearing devices

[0059] 4 Earplugs

[0060] 6 Earpiece

[0061] 8 Internal microphones

[0062] 10 External Microphone

[0063] 12 Housing

[0064] 14 Control Unit

[0065] 16 Ear Canal

[0066] 18 ANC units

[0067] 20 Feedforward Unit

[0068] 22 Feedback unit

[0069] 24 Signal Processing Unit

[0070] 26 Gain

[0071] 28 Signal Path

[0072] 30 Summer

[0073] 32 Additional amplifiers

[0074] A Output signal

[0075] Ext External signal

[0076] E1 First input signal (from external microphone)

[0077] E2 Second input signal (from internal microphone)

[0078] fb feedback signal, correction signal

[0079] ff Feedforward signal, correction signal

[0080] Noise

[0081] P1 External path (acoustic)

[0082] P2 Internal Path (Acoustic)

[0083] P3 Third Path (Acoustic and Electrical)

[0084] S signal (modified, amplified)

Claims

1. A method for operating a hearing device (2), a. wherein the hearing device (2) has an ANC unit (18), b. Among them, The ANC unit (18) has a feedforward unit (20) which outputs a feedforward signal (ff) to suppress external interfering noise entering the ear canal (16) of the user of the hearing device (2) from the outside. c. wherein the ANC unit (18) has a feedback unit (22) which outputs a feedback signal (fb) to suppress internal interference noise present in the ear canal (16), d. wherein the hearing device (2) has a signal processing unit (24) having an adjustable gain (26) and amplifies an input signal (E1) of the hearing device (2) and outputs it as an amplified signal (S), e. wherein the feedback signal (fb) is used as a measure for the user's own voice and the gain (26) of the signal processing unit (24) is set as a function of the feedback signal (fb) and therefore also as a function of the user's own voice, The gain (26) is set in a frequency-dependent manner, that is, the gain (26) is set only within the frequency range in which one's own voice is present.

2. The method according to claim 1, in, The feedforward unit (20) suppresses external interference noise in the case of a user's own voice activity, so that the feedback signal (fb) mainly contains the user's own voice, and then the gain (26) is set according to the user's own voice.

3. The method according to claim 1 or 2, in, The feedback signal (fb) has an amplitude, and wherein the gain (26) decreases as the amplitude increases.

4. The method according to claim 1 or 2, in, Phases of own voice activity and phases without own voice activity are distinguished based on the feedback signal (fb), so that own voice detection is simultaneously performed by means of the ANC unit (18).

5. The method according to claim 1 or 2, in, The ANC unit (18) and the signal processing unit (24) are combined to form an OVP unit. The OVP unit recognizes the own voice according to the feedback signal (fb) of the feedback unit (22) on the one hand, and processes the own voice with the help of the signal processing unit (24) according to the feedback signal (fb) on the other hand.

6. The method according to claim 1 or 2, in, The feedback unit (22) has an operating range which includes only frequencies up to a critical frequency, Therein, however, for frequencies above the critical frequency, the gain (26) is set depending on the feedback signal.

7. The method according to claim 1 or 2, in, The hearing device (2) has an external microphone (10) which generates an input signal (E1), which is then fed to the feedforward unit (20) to generate the feedforward signal (ff).

8. The method according to claim 1 or 2, in, The input signal (E1) is a first input signal (E1), and wherein the hearing device (2) has an internal microphone (8) which generates a second input signal (E2), which is fed to the feedback unit (22) to generate the feedback signal (fb).

9. The method according to claim 1 or 2, in, The hearing device (2) is designed for closed delivery and, for this purpose, has an earplug (4) in order to close the auditory canal (16) during normal use of the hearing device (2).

10. The method according to claim 1 or 2, in, The modified signal (S), the feedback signal (fb) and the feedforward signal (ff) are combined with one another to form an output signal (A), which is then output via an earpiece (6) of the hearing device (2).

11. The method according to claim 10, in, The output signal (A) is amplified by an additional amplifier (32) of the hearing device (2) before being output via the earpiece (6).

12. A hearing device (2) having a control unit (14) which is designed to carry out the method according to any one of claims 1 to 11.

Images