METHOD FOR OPERATING A HEARING AID

Description

[0001] The invention relates to a method for operating a hearing aid which has at least two input transducers and at least one output transducer, wherein an output signal is formed on the basis of directional signals which are generated from the input signals of the input transducers, which output signal is converted by the output transducer into a sound signal.

[0002] Hearing aids are portable hearing aids designed to provide hearing assistance to people with hearing loss or hard of hearing. To meet a wide range of individual needs, different types of hearing aids are available, such as behind-the-ear (BTE) hearing aids, receiver-in-the-canal (RIC) hearing aids, and in-the-ear (ITE) hearing aids, such as in-the-ear (concha) hearing aids or in-the-canal (ITE) hearing aids (CIC: Completely-In-Channel), or invisible-in-the-Channel (IIC). The hearing aids listed here are worn on the outer ear or in the ear canal of the hearing aid user. Bone conduction, implantable, and vibrotactile hearing aids are also available on the market. These devices stimulate the impaired hearing either mechanically or electrically.

[0003] Such hearing aids generally have an input transducer, an amplifier, and an output transducer as their essential components. The input transducer is usually an acoustoelectrical transducer, such as a microphone, and / or an electromagnetic receiver, such as an induction coil or a (radio frequency, RF) antenna. The output transducer is usually implemented as an electroacoustic transducer, such as a miniature loudspeaker (earpiece), or as an electromechanical transducer, such as a bone conduction receiver. The amplifier is usually integrated into a signal processing unit. Power is typically supplied by a battery or rechargeable accumulator.

[0004] In a so-called binaural hearing aid device, two hearing aids of this type are worn by one user, with a communication link between the hearing aids. During operation, data, possibly even large amounts of data, are exchanged wirelessly between the hearing aid in the right and left ear. The exchanged data and information enable particularly effective adaptation of the hearing aids to the respective acoustic environment. In particular, this provides the user with a particularly authentic surround sound and improves speech understanding, even in noisy environments.

[0005] When using hearing aids, handling conversational situations is one of the core problems. This is primarily due to the fact that important information is often conveyed to hearing aid users in face-to-face conversations. Therefore, for the sake of the most reliable information transmission possible, particular attention must be paid to the intelligibility of speech for hearing aid users.On the other hand, speech intelligibility is often impaired by the fact that typical conversation situations are overlaid by a high proportion of background and disturbing noise, as can be the case, for example, in a conversation with several people who do not speak in an orderly manner one after the other, or in a conversation in a closed room in which other groups of people contribute to an increased noise level through their conversations (so-called "cocktail party" listening situation).

[0006] To improve speech intelligibility, modern hearing aids often employ a beamforming or directional microphone algorithm, which directs a narrow directional pattern, such as a directional cone, toward the conversation partner. Such a directional cone acts as a filter across the hearing aid's input signals, amplifying the conversation partner's speech signal while significantly suppressing noises originating from other directions.

[0007] For a listening situation in which the conversation partner of a hearing aid user is moving relative to the user, previous algorithms for improving speech intelligibility, which suppress background noise using a directional characteristic, are usually not sufficient, since the corresponding directional characteristic would have to be continuously adapted to the changing position of the conversation partner, which leads to complications, especially when the moving conversation partner is not the only speaker in the vicinity of the user, and thus the recognition of the position of the conversation partner is made considerably more difficult due to the presence of the other speakers.

[0008] Document US 10 547 956 B2 discloses a method for operating a hearing aid having a first input transducer for generating a first input signal from an ambient noise signal and a second input transducer for generating a second input signal from the ambient noise signal, the method comprising: assigning a first direction to a first signal source; forming a first directional signal oriented in the first direction based on the first input signal and the second input signal; examining signal components of the first directional signal for the presence of a wanted signal from a wanted signal source predetermined with regard to a type thereof; predetermining spectral properties of the wanted signal source for examining the signal components of the first directional signal for the presence of the wanted signal;and determining a probability value for signal components compatible with the spectral features contained in the first directional signal, and inferring that a wanted signal is present if the probability value exceeds a predetermined first threshold; and which comprises defining a specific speaker as the wanted signal source and determining a human speech signal of the speaker as the wanted signal.

[0009] Document EP 3 328 097 A1 discloses a hearing aid comprising - an input unit for providing a plurality of electrical input signals representing sound in the user's environment - a signal processing unit providing a processed signal based on one or more of the plurality of electrical input signals, and - an output unit comprising an output transducer for converting the processed signal or a signal originating therefrom into a stimulus perceivable by the user as sound;wherein the input unit comprises at least a first input transducer for receiving a sound signal from the environment and for providing at least a first electrical input signal, and a first signal strength detector for providing a signal strength estimate of the at least one first electrical input signal, referred to as a first signal strength estimate, wherein the at least one first input transducer is arranged on the head, remote from the ear canal, - a comparison unit operatively coupled to the first and second signal strength detectors and configured to compare the first and second signal strength estimates and provide a signal strength comparison measure indicative of the difference between the signal strength estimates;and - a control unit for providing an own voice detection signal indicating whether or not the user's own voice is present in the current noise in the user's environment, the own voice detection signal being dependent on the signal strength comparison measure;

[0010] The document DE 10 2019 205709 B3 discloses a method for directional signal processing for a hearing aid, wherein a first input signal is generated from a sound signal of the environment by a first input transducer of the hearing aid, wherein a second input signal is generated from the sound signal of the environment by a second input transducer of the hearing aid, wherein a first calibration directional signal is generated based on the first input signal and the second input signal, which has a relative attenuation in the direction of a first useful signal source of the environment, wherein a second calibration directional signal is generated based on the first input signal and the second input signal, which has a relative attenuation in the direction of a second useful signal source of the environment, wherein a relative gain parameter is determined based on the first calibration directional signal and the second calibration directional signal,wherein a first processing directional signal and a second processing directional signal are generated based on both the first input signal and the second input signal, wherein a source-sensitive directional signal is generated based on the first processing directional signal, the second processing directional signal and the relative gain parameter, and wherein an output signal of the hearing aid is generated based on the source-sensitive directional signal.

[0011] Document EP 2 811 762 A1 discloses a method for beam shaping for hearing aid systems, wherein the hearing aid system comprises a left hearing aid device and a right hearing aid device which are arranged on a head of a wearer according to the application, wherein the left hearing aid device has a left acousto-electrical transducer which converts sound waves arriving at the left hearing aid device into a left input signal and the right hearing aid device has a right acousto-electrical transducer which converts sound waves arriving at the right hearing aid device into a right input signal, wherein the hearing aid system has a signal processing device which is in signal connection with the left and the right acousto-electrical transducer and receives the left and the right input signal, the method comprising the steps of: providing a plurality of different linear combinations of the left input signal and the right input signal;Evaluating the linear combinations according to a given signal criterion; selecting a linear combination depending on the evaluation as a beam signal.

[0012] EP 3 337 187 A1 and EP 3 337 189 A1, for example, disclose hearing aids in which a number of directional signals with different directional characteristics are used from the microphone signals to generate an output signal. This is also referred to below as a multi-beam concept. Such a multi-beam concept enables, for example, a so-called ambient beam or ambient directional cone (region beam). Such an ambient beam is automatically activated, for example, when the hearing aid wearer is having a conversation with more than one target speaker, or when the hearing aid wearer is having a conversation with a single speaker in a displaced position without having to turn their head towards the conversation partner.

[0013] The ambient beam algorithm, for example, is designed to specifically cover a spatial area in which the conversation partners are located by controlling and combining several flexible, narrow directional signals or directional patterns from different directions, which are applied in parallel. This ambient beam generates various new directional pattern or directional cone patterns tailored to the listening situation in which the active conversation partners are located.

[0014] However, the technical problem here is that the conversation partners in the output signal still have the same original speech volume, even though background noise and external noise in the distance can be effectively reduced. This means there is no amplified hearing. In other words, the speakers are not louder and do not stand out in the conversation situations in which the hearing aid wearer finds themselves.

[0015] The invention is based on the object of providing a particularly suitable method for operating a hearing aid. In particular, a speech signal is to be emphasized more strongly in the output signal without losing information from the surroundings. The invention is also based on the object of providing a particularly suitable hearing aid.

[0016] With regard to the method, the problem is solved according to the invention with the features of claim 1 and with regard to the hearing aid with the features of claim 5. Advantageous embodiments and further developments are the subject of the dependent claims.

[0017] The advantages and embodiments described with regard to the method can also be applied to the hearing aid, and vice versa. Where method steps are described below, advantageous embodiments for the hearing aid result, in particular, from the fact that the hearing aid is designed to perform one or more of these method steps.

[0018] The method according to the invention is intended for operating a hearing device, in particular a hearing aid device, and is suitable and designed therefor.

[0019] The hearing aid has at least two input transducers for generating input signals and at least one output transducer for generating a sound signal.

[0020] According to the method, at least two directional signals with different directional characteristics are formed from the input signals, with the directional signals then being examined for the presence of a useful signal. A first weighting factor is assigned to the directional signal with the largest signal component of the useful signal, and a second weighting factor is assigned to the other directional signals. According to the invention, the directional signals are multiplied by the respectively assigned weighting factor, and an output signal is then formed from this, which is converted into an acoustic signal by the output transducer. The weighting factors are preferably linear factors. This realizes a particularly suitable method for operating the hearing aid.In particular, this creates a multi-beam or ambient beam concept in which the desired signal or desired signal components in the output signal can be automatically made more prominent and louder using weighting factors. This creates a multi-beam or ambient beam extension that can be particularly flexibly adapted to the respective listening situation and reduces background noise and distant interfering signal sources.

[0021] A directional signal is understood to be a signal which has a particularly high sensitivity for a reference sound from a reference sound source within a specific angular range, and which has a significantly reduced sensitivity with respect to the reference sound when the reference sound source is arranged outside the given angular range. In particular, the directional signal can have a maximum in its sensitivity with respect to the reference sound at a given central angle, with the sensitivity to the reference signal decreasing with increasing angular distance from the central angle. This angular dependence is also referred to below as the directional characteristic. Directional characteristics include, in particular, directional cones or directional lobes (rays, beams), i.e. directional characteristics with a club-shaped or conical geometry.Such directional signals or directional characteristics can be generated from the input signals, for example, using "sum and delay" methods.

[0022] The examination for the presence of the wanted signal is carried out, for example, by examining whether the wanted signal is similar to a specified wanted signal source in terms of type. A specified wanted signal source includes, in particular, a wanted signal source that can be specified and / or recognized based on the spectral properties of signal components of the generated wanted signal, for example, a specific speaker whose speech signal can be distinguished from the speech signals of other possible speakers in the hearing aid based on its spectral properties and the distribution of formats. For example, spectral characteristics of the wanted signal source are specified, whereby a probability is determined as to whether the directional signals contain signal components that are compatible with the spectral characteristics.For example, if a predefined probability threshold is exceeded, the presence of the wanted signal is inferred. Alternatively, a voice activity detection (VAD) unit can detect speakers or speech signals in the input signal, and potential target speakers or wanted signals can be identified.

[0023] The method according to the invention essentially implements a listening mode that enables "extended or amplified hearing" (augmented listening) or "enhanced hearing" or "hearing with enhanced senses." This makes it possible to automatically emphasize the wanted signal or the wanted signal source, for example, an active conversation partner, more prominently and loudly than usual in the output signal using the first weighting factor. The wanted signal source is thus perceived as being closer to the hearing aid wearer. This means that the wanted signal source is "zoomed in" and more strongly emphasized in the output signal. The second weighting factors are preferably selected such that ambient background noise is well preserved. The weighting factors thus essentially implement automatic volume control toward the wanted signal source, for example, toward the active speaker.This automatic, directional volume control (ADVC) makes it easier for the hearing aid wearer to listen to conversations.

[0024] The directional signal multiplied by the first weighting factor, or rather its directional characteristic, preferably exhibits a comparatively small angular spread. In other words, this directional signal exhibits a comparatively narrow beam, i.e., a narrow angular spread, by means of which the wanted signal or the wanted signal source is tracked.

[0025] If no useful signal is detected, for example, if no speaker is active, the method according to the invention is automatically faded out or terminated. This means that amplification is preferably applied only when necessary. This preferably results in intelligent amplification.

[0026] In a suitable embodiment, the output signal is formed from a superposition of the directional signals multiplied by the weighting factors. In particular, a linear superposition is performed. This means that the weighted directional signals are preferably added or summed together.

[0027] In an advantageous embodiment, the first weighting factor and / or the second weighting factor are adjusted depending on the respective current environmental situation. The conjunction "and / or" is to be understood here and below in such a way that the features linked by this conjunction can be configured both together and as alternatives to one another.

[0028] An environmental situation is understood here, in particular, to be an acoustic environmental situation or a hearing situation. The environmental situation is identified and characterized, for example, by means of situation recognition and / or at least one level measurement and / or at least one algorithm of the hearing aid or signal processing. For example, the environmental situation is classified according to certain criteria, and each of these classes is assigned a specific setting of the weighting factors. The weighting factors are preferably controlled automatically by a scene analysis based on a combination of speaker localization and tracking, background noise estimates, estimation of speech intensity, signal-to-noise ratio, etc.

[0029] For example, the weighting factors are determined based on frequency and time. In particular, this means that the weighting factors are dimensioned differently in different frequency bands. Especially in the case of speech signals, characteristic spectral characteristics of the voices of the conversation partners can also be taken into account. To keep the background noise in the output signal as natural as possible, even though the useful signal is amplified with the first weighting factor, the second weighting factor is applied across all frequencies or only to specific frequencies.

[0030] The weighting factors are set within predefined (value) ranges. Depending on the hearing aid wearer's preference, these value ranges can be set either in fitting software provided by a hearing care professional (HCP) or via external devices, such as a smartphone application. This means that the hearing aid professional can decide for each hearing aid wearer whether the user's preference or need is more toward the enhanced hearing offered by the invention than toward conventional hearing.

[0031] According to the invention, the first weighting factor is larger than the second weighting factor. This ensures that the desired signal appears amplified or louder in the output signal.

[0032] According to the invention, the second weighting factor has a value range between zero (0) and one (1). This means that the second weighting factor is greater than or equal to zero (≥ 0) and less than or equal to one (≤ 1).

[0033] According to the invention, the first weighting factor is greater than or equal to zero and less than or equal to an adjustable parameter. The parameter is, for example, greater than or equal to one, but in particular, the parameter is greater than the upper limit of the second weighting factor. Changing or optimizing the parameter enables easy setting of a desired amplification factor for the useful signal.

[0034] According to the invention, the parameter is adjusted depending on the signal level of the wanted signal. This means that the degree of amplification is controlled by the original input volume of the wanted signal. If the signal level of the wanted signal falls below a certain threshold, the first weighting factor is automatically increased. For example, if a conversation partner speaks quietly during a conversation, the wanted signal is automatically amplified even more. If, however, the speaker is already loud, the amplification or the first weighting factor is automatically reduced.

[0035] In a preferred application, the wanted signal is a speech signal. This means that the wanted signal source is a specific speaker or conversation partner, and the wanted signal is a (human) speech signal. The method is particularly advantageous when a speaker is the wanted signal source, since, on the one hand, a specific speech signal can be identified based on a multitude of spectral parameters characteristic of the voice and speech, thus enabling particularly reliable amplification using the first weighting factor. This significantly improves the intelligibility of the speech signal.

[0036] The hearing aid according to the invention is used in particular to provide sound to a hearing-impaired user (hearing system user). The hearing aid is designed to receive sound signals from the environment and output them to a user of the hearing aid. For this purpose, the hearing aid has at least two input transducers, in particular acousto-electrical transducers, such as microphones, and at least one output transducer, in particular an electro-acoustic transducer, such as an earpiece. During operation of the hearing aid, the input transducers receive sound signals (noises, tones, speech, etc.) from the environment and convert them into an electrical input signal. An electrical output signal is generated from the electrical input signal by modifying the input signal in a signal processing system. Signal processing, for example, is a part of the hearing aid.The input and output transducers, as well as the signal processing, are housed in a hearing aid housing. The housing is designed so that it can be worn by the user on the head and near the ear, e.g., in the ear, on the ear, or behind the ear. The hearing aid is preferably designed as a BTE hearing aid, ITO hearing aid, or RIC hearing aid.

[0037] The hearing aid, in particular the signal processing unit, further comprises a controller, i.e., a control unit. The controller is generally configured—in terms of programming and / or circuitry—to implement the method according to the invention described above. The controller is thus specifically configured to determine a number of directional signals from the input signals, analyze signal components of a useful signal in the directional signals, and assign weighting factors to the directional signals depending on the signal components, multiply them by these weighting factors, and generate an output signal for the output transducer.

[0038] In a preferred embodiment, the controller is formed, at least in its core, by a microcontroller with a processor and a data memory, in which the functionality for carrying out the method according to the invention is implemented in the form of operating software (firmware), so that the method - possibly in interaction with a device user - is carried out automatically when the operating software is executed in the microcontroller. Within the scope of the invention, however, the controller can alternatively also be formed by a non-programmable electronic component, such as an application-specific integrated circuit (ASIC), in which the functionality for carrying out the method according to the invention is implemented using circuitry.

[0039] An additional or further aspect of the invention provides that the hearing aid is designed to be binaural and, for this purpose, comprises two individual devices, each of which has at least two input transducers and at least one output transducer and is thus configured to receive sound signals from the environment and output them to a user of the hearing aid. For example, a wireless interface is provided for data exchange between the two individual devices. The directional characteristics of the directional signals are, in particular, binaural directional characteristics, meaning that the directional signals are determined based on the input signals of both individual devices.

[0040] With a binaural hearing aid, the user wears the two individual devices on different sides of the head, so that each device is assigned to a specific ear. Alternatively to a binaural hearing aid, a monaural hearing aid with just one individual device is also suitable. The explanations regarding a monaural hearing aid apply analogously to a binaural hearing aid, and vice versa.

[0041] Exemplary embodiments of the invention are explained in more detail below with reference to a drawing. In these, schematic and simplified representations: Fig. 1 shows a binaural hearing aid, and Fig. 2 shows a block diagram of the sequence of a method for operating a hearing aid.

[0042] Corresponding parts and sizes are always provided with the same reference symbols in all figures.

[0043] The Fig. 1 shows the basic structure of a hearing aid 2 according to the invention. In this exemplary embodiment, the hearing aid 2 is designed as a binaural hearing aid device with two signal-coupled hearing aids or individual devices 4a, 4b. The individual devices 4a, 4b are designed, for example, as behind-the-ear hearing aids (BTE). The individual devices 4a, 4b are or can be coupled to each other via a wireless communication link 6.

[0044] The communication connection 6 is, for example, an inductive coupling between the individual devices 4a and 4b; alternatively, the communication connection 6 is designed, for example, as a radio connection, in particular as a Bluetooth or RFID connection, between the individual devices 4a and 4b.

[0045] The structure of the individual devices 4a, 4b is explained below using the example of the individual device 4a. The individual device 4a comprises, as shown in the Fig. 1 schematically depicted is a device housing 8, into which one or more microphones, also referred to as (acousto-electrical) input transducers 10, are built. The input transducers 10 record a sound or acoustic signals in the environment of the hearing aid 2 and convert them into electrical acoustic data as input signals 12.

[0046] The input signals 12 are processed by a controller 14 of a signal processing device 16, which is also arranged in the device housing 10. Based on the input signals 12, the signal processing device 16 generates an output signal 18, which is passed to a loudspeaker or receiver 20. The receiver 20 is designed as an (electro-acoustic) output transducer 20, which converts the electrical output signal 18 into an acoustic signal or sound signal and outputs it. In the individual BTE device 4a, the acoustic signal is transmitted to the eardrum of a hearing system user via a sound tube (not shown in detail) or an external receiver, which is fitted with an earmold seated in the ear canal. However, an electro-mechanical output transducer 20 is also conceivable as the receiver, for example, as in a bone conduction receiver.

[0047] The power supply of the individual device 4a and in particular of the signal processing device 16 is provided by a battery 22 accommodated in the device housing 8.

[0048] The signal processing device 16 is connected to a first transceiver 24 and a second transceiver 26 of the individual device 4a. The transceiver 24 serves, in particular, to transmit and receive wireless signals via the communication connection 6, and the transceiver 26 serves to transmit and receive wireless signals via a communication connection to an additional device external to the hearing aid, for example, to a smartphone. For example, it is also conceivable for only one transceiver to be provided for both communication connections 8.

[0049] In the Fig. 2 A block diagram illustrates a method for operating the hearing aid 2 during a listening situation in which a conversation partner 28 is positioned at an angle of approximately 45° with respect to a frontal direction 30 of the hearing aid user (hearing aid wearer). The listening situation is such that the conversation between the hearing aid user and the conversation partner 28 is overlaid by background noise originating from noise sources distributed throughout the environment.

[0050] The conversation partner 28 is a useful signal source with regard to the signal processing or method described below, wherein the speech or speech signal of the conversation partner 28 represents a useful signal.

[0051] The following describes the method for a single device 4a, 4b, which is carried out in the controller 14. However, the method is preferably carried out binaurally, so that the output signal 18 is generated based on the input signals 12 of the input converters 10 of both individual devices 4a, 4b.

[0052] The sound signal 32, which results from the wanted signal and the background noise (interference, noise signals), is detected by the input transducers 10, each of which generates a corresponding input signal 12. Through spatial filtering, a number of directional signals 34 with different directional characteristics 36 are formed from the input signals 12.

[0053] Examples include the Fig. 2Four directional signals 34a, 34b, 34c, 34d for four different directional characteristics 36a, 36b, 36c, 36d are shown schematically. The directional characteristics 36a, 36b, 36c, 36d are each designed, for example, as club- or conical directional beams, each having the same angular expansion 38 and differing only with respect to a central angle 40 with respect to the frontal direction 30. The central angle 40 is defined in each case by the angle between the direction of maximum sensitivity of the directional characteristics 36a, 36b, 36c, 36d and the frontal direction 30 of the hearing aid user.

[0054] A selection unit 42 uses the directional signals 34a, 34b, 34c, 34d of the directional characteristics 36a, 36b, 36c, 36d to determine the presence of the wanted signal source or the conversation partner 28 in the respective direction of the central angle 40 via the corresponding signal levels. In the embodiment shown, the directional signal 34c has the largest signal component of the wanted signal.

[0055] Subsequently, in an allocation unit 44, a first weighting factor bw1 is assigned to the directional signal 34c and a second weighting factor bw2 is assigned to each of the remaining directional signals 34a, 34b, 34d. The directional signals 34a, 34b, 34c, 34d are multiplied by the respective weighting factor bw1, bw2. The weighting factors bw1 and bw2 can be multiplied by the directional signals 34a, 34b, 34c, 34d across all frequencies or applied to specific frequencies (e.g., frequencies relevant for speech understanding). The weighting factors bw1, bw2 can thus be dimensioned differently in different frequency bands.

[0056] The directional signals 34a, 34b, 34c, 34d multiplied by the weighting factors bw1, bw2 are then mixed together in a mixing unit 46 by a linear superposition.

[0057] Expressed in formulas, the superposition signal for two directional signals (Beam1, Beam2) for a frequency f at a time t is, for example, as: Superpositionssignal f t = bw 1 f t × Beam 1 f t + bw 2 f t × Beam 2 f t

[0058] The resulting superposition signal forms, for example, the output signal 18 for the output transducer 20, which converts the output signal 18 into an audible sound signal. Preferably, however, the superposition signal of the mixing unit 46 is fed to a signal processing block (not shown in detail) of the signal processing unit 16, in which all further processing algorithms specific to the hearing aid 2 are executed. The signal processing block then generates the output signal 18. The signal processing block can also be amplified at the relevant frequencies to make the speaker's voice even clearer in the output signal 18.

[0059] The method described above is implemented in particular as a multi-beam or ambient beam concept, in which the wanted signal or wanted signal components in the output signal 18 are automatically made more prominent and louder by the weighting factors bw1, bw2. This method essentially implements a listening mode that enables "extended or augmented listening." The wanted signal source or the conversation partner 28 is thus perceived by the hearing aid user as (spatially) closer. This means that the wanted signal source is "zoomed in" and emphasized more strongly in the output signal 18.

[0060] For this purpose, the weighting factor bw1 is larger than the weighting factor bw2. In particular, the weighting factors bw2 are greater than or equal to zero and less than or equal to one (0 ≤ bw2 ≤ 1). The weighting factors bw2 are preferably chosen such that ambient noise in the background is well preserved. The weighting factor bw1 is greater than or equal to zero and less than or equal to an adjustable parameter (0 ≤ bw1 ≤ parameter). The value ranges of the weighting factors bw1, bw2 and in particular the parameters can be set, for example, depending on the preference of the hearing aid wearer, either in fitting software from a hearing aid acoustician or via external additional devices, e.g. with application software (application, app) on a smartphone.

[0061] The weighting factors bw1, bw2, or their values and / or the parameters, can be adjusted depending on the current ambient or listening situation. The ambient situation is identified and characterized, for example, by means of situation recognition 48. The weighting factors bw1, bw2 are preferably controlled automatically by a scene analysis based on a combination of speaker localization and tracking, background noise estimation, speech intensity estimation, signal-to-noise ratio, etc.

[0062] The invention is not limited to the exemplary embodiments described above. Rather, other variants of the invention can also be derived therefrom by those skilled in the art without departing from the scope of the invention. In particular, all individual features described in connection with the exemplary embodiments can also be combined with one another in other ways without departing from the scope of the invention. List of reference symbols

[0063] 2Hearing aid 4a, 4bSingle device 6Communication connection 8Device housing 10Input transducer 12Input signal 14Controller 16Signal processing 18Output signal 20Output transducer 22Battery 24Transceiver 26Transceiver 28Interlocutor 30Frontal direction 32Sound signal 34a, 34b, 34c,34dDirectional signal 36a, 36b, 36c, 36dDirectional characteristic 38Angle expansion 40Central angle 42Selection unit 44Assignment unit 46Mixing unit 48Situation detection bw1, bw2Weighting factor

Claims

1. Method for operating a hearing aid (2) which comprises at least two input converters (10) and at least one output converter (20): - wherein the input converter (10) respectively generates an input signal (12) from an acoustic signal (32) in the environment; - wherein at least two directional signals (34a, 34b, 34c, 34d) having different directional characteristics (36a, 36b, 36c, 36d) are formed from the input signals (12); - wherein the directional signals (34a, 34b, 34c, 34d) are analyzed for the presence of a useful signal; - wherein a first weighting factor (bw1) is assigned to the directional signal (34c) having the largest signal component of the useful signal, and a second weighting factor (bw2) is assigned to the other directional signals (34a, 34b, 34d); - wherein the first weighting factor (bw1) is greater than the second weighting factor (bw2); - wherein the second weighting factor (bw2) is greater than or equal to zero, and lower than or equal to one; - wherein the first weighting factor (bw1) is greater than or equal to zero, and lower than or equal to an adjustable parameter; - wherein the parameter is set in accordance with a signal level of the useful signal; and - wherein the directional signals (34a, 34b, 34c, 34d) are multiplied by the respectively assigned weighting factor (bw1, bw2) and, thereafter, an output signal (18) is formed herefrom, which signal is converted by the output converter (20) into an acoustic signal.

2. Method according to Claim 1, characterized in that the output signal (18) is formed by a superposition of directional signals (34a, 34b, 34c, 34d) which are multiplied by the weighting factors (bw1, bw2).

3. Method according to Claim 1 or Claim 2, characterized in that the first weighting factor (bw1) and / or the second weighting factor (bw2) are set in accordance with an ambient situation.

4. Method according to one of claims 1 to 3 characterized in that the useful signal is a speech signal.

5. Hearing aid (2), in particular a binaural hearing aid, comprising at least one input converter (10) for generating input signals (12) and at least one output converter (20) for generating an acoustic signal, and a controller (14) for executing a method according to one of Claims 1 to 4.