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EP 1 558 059 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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16.06.2010 Bulletin 2010/24 |
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Date of filing: 18.04.2005 |
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International Patent Classification (IPC):
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Controlling a gain setting in a hearing instrument
Verstärkungseinstellungskontrolle für einen Hörinstrument
Contrôle de gain dans une prothèse auditive
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Designated Contracting States: |
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CH DE DK LI |
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Date of publication of application: |
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27.07.2005 Bulletin 2005/30 |
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Proprietor: PHONAK AG |
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8712 Stäfa (CH) |
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Inventors: |
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- Allegro Baumann, Silvia
6314 Unterägeri (CH)
- Launer, Stefan
8053 Zürich (CH)
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Representative: Walser, Peter |
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Frei Patentanwaltsbüro
Postfach 1771 8032 Zürich 8032 Zürich (CH) |
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References cited: :
EP-A- 0 941 014 WO-A-2004/110099
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EP-A- 1 465 454 WO-A-2004/114722
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- THOMAS A. POWERS, PAMELA BURTON: "Wireless technology designed to provide true binaural
amplification" THE HEARING JOURNAL, [Online] vol. 58, 1 January 2005 (2005-01-01),
XP002345661 Retrieved from the Internet: URL:http://www.siemens-hearing.com/_common
/pdf/WP_HJ0105.pdf> [retrieved on 2005-09-19]
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| Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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FIELD OF THE INVENTION
[0001] This invention is in the field of processing signals in or for hearing instruments.
It more particularly relates to a method of controlling a gain setting in a hearing
instrument, and to a hearing instrument.
BACKGROUND OF THE INVENTION
[0002] Binaural loudness summation is known in the field of audiology. Binaural loudness
summation is the effect that the loudness of sound is greater when it is presented
to both ears simultaneously than when it is presented to one ear alone. The magnitude
of this effect varies between individuals. Usually, the increase in loudness is approximately
3 dB when the intensity level is near the person's hearing threshold. The effect increases
at suprathreshold level.
[0003] Binaural loudness summation is one of the advantages of binaural amplification. For
persons with bilateral hearing loss who are equipped with two hearing instruments,
the applied gain may be reduced. Due to the reduced gain, the chance of feedback is
decreased, and larger vents may be used.
[0004] Since the optimal gain is different between monaural and binaural fittings, the loss
of binaural loudness summation accounts for a non-ideal gain fitting if a user, who
usually wears two hearing instruments, occasionally only uses one hearing instrument.
This may happen if the user deliberately only wears one hearing instrument or if one
of the hearing instruments is not available.
[0005] WO 2004/114722 discloses a binaural hearing aid system, wherein an environment sound is detected
based on a signal from the first hearing instrument and a signal from the second hearing
instrument. The signal processing algorithm of both hearing instruments is selected
based on the environment sound.
[0006] In
EP 1 465 454, a hearing instrument is described that automatically detects whether it is in the
user's ear.
SUMMARY OF THE INVENTION
[0007] It is an object of this invention to provide a method of controlling a gain in a
hearing instrument which allows to provide optimal gain characteristics in both, situations
when the user wears two hearing instruments and situations when the user only wears
one hearing instrument.
[0008] According to the invention, in a hearing instrument it is once or repeatedly checked
whether a second hearing instrument is present and active. If a second hearing instrument
is active on the contralateral side, a first gain setting is adopted. If, however,
no further hearing instrument is found to be active, a second gain setting is chosen.
The gain generated by the hearing instrument with the first gain setting may correspond
to the gain for binaural fitting, whereas the gain of the second gain setting is increased
in comparison. The second gain may simply correspond to the first gain increased by
a certain dB value. It may as an alternative be a specifically adapted gain characteristic
of a monaural fitting for the user.
[0009] "Gain" is usually defined as the ratio between an input signal and an output signal.
This ratio may be time-dependent and/or may be frequency dependent. In addition, the
gain may be situation dependent (i.e. different gain settings for different hearing
programs, which are associated to different acoustic situations).
[0010] In a preferred embodiment of the invention, there exists some wireless or wired communication
channel between the hearing instruments, across which there is a continuous or repeated
communication between the hearing instruments.
[0011] A wireless communication channel may be a radio signal transmission or an inductive
signal transmission (i.e., using magnetically coupled coils as antennas) or any other
suitable wireless communication channel. The signal used may be any signal transmitting
any information. In a most simple example, the signal may just be a characteristic
regularly repeated presence signal (e.g. a radio frequency carrier signal).
[0012] A wired communication channel may for example comprise a physical wire or may comprise
the frame of a user's glasses.
[0013] Since the only information that has to be transmitted is whether or not a second
hearing instrument is active, the communication channel does not have to have a large
bandwidth. Compared to prior art communication channels between two hearing instruments,
the communication channel may therefore consume comparatively little power.
[0014] One of the often encountered reasons for a situation where only one hearing instrument
of a binaural system is available is if the battery is empty. For this case, the remaining
hearing instrument may, according to a special embodiment of the invention, initiate
a signal informing the user of the battery failure of the unavailable hearing instrument
and reminding the user to replace the battery of said hearing instrument. Such a signal
may be a beep signal, a voice message (like for example "left hearing aid not available"
or "change battery of left hearing aid" etc.), a message displayed on a display unit
of a remote control etc. According to the prior art, it was possible to produce a
warning signal when the battery in a hearing instrument was not yet empty but found
to be low. However, it is a well-known fact that the battery charge level in a hearing
aid is a quantity that is difficult to measure, at least without extra hardware, so
that the "battery-low" warning signals are often unreliable.
[0015] A warning signal of this kind is, of course, not produced upon every check but for
example only once when the other hearing instrument is found to be unavailable for
the first time. The occurrence of such a signal may but does not have to depend on
a manually set switch value. For example, the user may switch to a monaural mode in
which he deliberately uses one hearing instrument only, in which case a signal will
not be output.
[0016] A signal warning the user of failure or imminent failure of the other hearing instrument
may also be initiated in situations where, in contrast to the above-described principle,
the gain setting of the remaining hearing instrument is not adapted in case the other
hearing instrument is inactive.
[0017] The term "hearing instrument" or "hearing device", as understood here, denotes on
the one hand hearing aid devices that are therapeutic devices improving the hearing
ability of individuals, primarily according to diagnostic results. Such hearing aid
devices may be Behind-The-Ear hearing aid devices or In-The-Ear hearing aid devices
(including the so called In-The-Canal and Completely-In-The-Canal hearing aid devices,
as well as partially and fully implanted hearing aid devices). On the other hand,
the term stands for devices which may improve the hearing of individuals with normal
hearing e.g. in specific acoustical situations as in a very noisy environment or in
concert halls, or which may even be used in the context of remote communication or
of audio listening, for instance as provided by headphones.
[0018] The hearing devices addressed by the present invention are so-called active hearing
devices which comprise at the input side at least one acoustical to electrical converter,
such as a microphone, at the output side at least one electrical to acoustical converter,
such as a loudspeaker (often also termed "receiver"), and which further comprise a
signal processing unit for processing signals according to the output signals of the
acoustical to electrical converter and for generating output signals to the electrical
input of the electrical to mechanical output converter. In general, the signal processing
circuit may be an analog, digital or hybrid analog-digital circuit, and may be implemented
with discrete electronic components, integrated circuits, or a combination of both.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In the following, embodiments of the invention are described with reference to drawings.
The drawings are all schematical and show:
- Fig. 1 a binaural hearing instrument system comprising two hearing instruments,
- Fig. 2 a diagram of a first embodiment of the method according to the invention,
- Fig. 3 an illustration of a gain increase in accordance with the first embodiment,
- Fig. 4 a diagram of a second embodiment of the method according to the invention,
- Fig. 5 an illustration of a gain increase in accordance with the second embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] The hearing instrument system of
Figure 1 comprises a set of two hearing instruments, each including at least one acoustic-to-electric
converter 1.1, 1.2 (often, two or even three acoustic-to-electric converters are available
in each hearing instrument), a signal processing unit (SPU) 3.1, 3.2 operable to apply
a time- and/or frequency-dependent gain to the input signal or input signals S
I,1, S
I,2 resulting in output signal S
O,1, S
O,2 and at least one electric-to-acoustic converter 5.1, 5.2. Between the two hearing
instruments - in the shown embodiment between the signal processing units - there
is a communication channel 6 by which the hearing instruments may exchange information.
The communication interfaces of the hearing instruments are denoted by 7.1 and 7.2.
[0021] An embodiment of the method according to the invention - as implemented in at least
one, preferably in both of the hearing instruments - is illustrated in
Figure 2. After initiation 11, a check 12 is carried out by the hearing instrument via the
communication channel. By the check it is determined whether the second hearing instrument
is active. For example, it is checked whether a characteristic signal is received
by a coil serving as antenna. The overall gain setting - which may in addition depend
on other parameters such as stored, pre-set user specific values, detected noise,
incoming sound direction, a loudness level or an amplification level pre-set by the
user etc. - applied to the input signal is chosen dependent on the result of this
check (gain application 16). A first gain setting 13 is applied in the case both hearing
instruments are functional. The first gain setting is adapted to binaural hearing
and accounts for the phenomenon of binaural loudness summation. In case one of the
hearing instruments is not functional, a second gain setting 14 is applied. The second
gain setting may be qualitatively different from the first gain setting and may be
based on different parameters (for example on different noise suppression algorithms,
on different time constants, etc.). It may as an alternative be calculated from the
first gain setting in an appropriate way, for example by adding a loudness and frequency
dependent value to the gain.
[0022] The second gain (corresponding to the second gain setting) is higher compared to
the first gain. In case the gain is frequency dependent, this means that an average
of the gain the audible part of the sound spectrum is higher. The second gain may
be specifically adapted to monaural hearing and to the characteristic hearing ability
of the ear to which the remaining hearing instrument is associated. In other words,
the second gain and possibly also the first gain need not be identical for both hearing
instruments of a hearing instrument system. An example of a gain increase in case
of a frequency dependent gain is illustrated very schematically in
Figure 3. A first gain curve 23 depicts the frequency dependence of the first gain, whereas
a second gain curve 24 shows the frequency dependence of the second gain. The second
gain does not have to be higher than the first gain for all frequencies, although
preferably in the part of the frequency spectrum which is most important for speech
perception for the user, the second gain is on average higher than the first gain.
[0023] The step of checking whether both hearing instruments are functional is preferably
repeated regularly.
[0024] Once the temporarily unavailable hearing instrument becomes available again - for
example since the battery has been replaced or since the instrument is functional
again - this will be detected, and the gain re-set to "binaural" (i.e. to the first
gain setting).
[0025] As an alternative to the repeated checking of the status of the other hearing instrument
("polling") a further possibility exists. According to an alternative, a status information
of a hearing instrument is transmitted to the other hearing instrument proactively,
at regular intervals or on special occasions, such as in case of imminent failure
(for example before the battery is empty). Once such a proactively sent status information
is received, a status information tag (or the like) in a memory of the receiving hearing
instrument may be set to "not active" (referring to the other hearing instrument).
The step of determining whether the other hearing instrument is active then includes
internally checking the status information tag. The status information tag is re-set
to "active" - for example manually or by a status information transmission by the
other hearing instrument when it is switched on - when the other hearing instrument
is activated again.
[0026] The hearing instrument may optionally once or repeatedly produce a signal 15 when
the check reveals that the other hearing instrument is not active. The signal may
for example be acoustical or may be a warning message displayed on a display field
of a remote control (not shown). By the signal, the user may for example be reminded
by the still functioning hearing aid to replace the battery of the other hearing instrument.
[0027] If the signal is acoustical, preferably the hearing instrument may manually be set
to a mode where the signal does not appear so that the user is not disturbed by the
signal in situations where he deliberately only uses only one hearing instrument.
[0028] A second embodiment of the method according to the invention is shown in
Figure 4. The embodiment of Figure 4 may be viewed as special, particularly simple variant
of the embodiment of Figure 2. As in said previous embodiment, after initiation 11,
a check 12 is carried out by the hearing instrument via the communication channel.
A gain setting determination 31 - the gain may again depend on parameters such as
be fixedly stored, for example user-characteristic values, detected noise, incoming
sound direction a loudness level or amplification level pre-set by the user etc. -
is carried out before or after or simultaneously to the check. If the check reveals
that the other hearing instrument is not active, the gain is increased 32 in a predetermined
manner. It may for example be increased by adding a fixed dB value (for example between
2 dB and 5 dB) for all frequencies. This is illustrated in
Figure 5, where the second gain curve 44 corresponds to the first gain curve plus a fixed
value which is constant for all frequencies. As an alternative, a fixed value which
depends on the frequency may be added.
[0029] The embodiment of Figure 4 features the advantage that it is relatively simple. Also
the embodiment of Figure 4 may comprise providing a signal 15 when it has been found
that the other hearing instrument is not active.
[0030] A process of the kind shown in Figures 2 and 4 may be carried out in both hearing
instruments. If one hearing instrument fails, the other one will switch to the second
gain (or the increased gain).
[0031] A hearing instrument according to the invention comprises means for carrying out
any embodiment of the above described method. A hearing instrument system comprises
two hearing instruments, shaped and adapted to be placed behind or in the left and
right ear of the user, respectively. In the case of wireless communication, the communication
interfaces of the two hearing instruments are for example adjusted to each other so
that only signals of the corresponding hearing instruments of the hearing instrument
system may be detected or that signals of hearing instruments of other hearing instrument
systems - for example of hearing instruments worn by other persons nearby - may be
distinguished. As an alternative, universal interfaces may be used, so that upon replacement
of one hearing instrument no adaptation has to be done.
1. A method of controlling a gain setting of a hearing instrument, the hearing instrument
being operable to determine an output audio signal from at least one input signal
and to supply said output audio signal to one ear of a user, the hearing instrument
comprising a communication interface (7.1, 7.2) operable to establish a communication
link to a further hearing instrument associated with the other ear of the user, characterised in that the method comprises the steps of determining, using the communication interface,
whether the further hearing instrument for the other ear of the user is active, of
adopting a first gain setting if the further hearing instrument for the other ear
of the user is active, and of adopting a second gain setting different from the first
gain setting if the further hearing instrument is not active.
2. A method according to claim 1, wherein an average gain value of the first gain setting
is lower than an average gain value of the second gain.
3. A method according to claim 2, wherein the gain in accordance with the second gain
setting corresponds to the gain in accordance with the first gain setting increased
by a fixed, possibly frequency dependent, dB value.
4. A method according to any one of the previous claims, wherein the step of determining
whether a further hearing instrument is active is carried out repeatedly at regular
or random time intervals.
5. A method according to any one of the previous claims, wherein, for determining whether
the further hearing instrument associated with the other ear of the user is active,
the hearing instrument sends a request signal demanding a status information from
the potential further hearing instrument.
6. A method according to any one of claims 1 to 4, wherein, in case the further hearing
instrument is active, it sends a status information to the hearing instrument proactively.
7. A method according to any one of the previous claims, wherein at least once a signal
perceivable by the user is initiated by the still active hearing aid when the further
hearing instrument is not active.
8. A hearing instrument system comprising two hearing instruments, each comprising a
signal processing unit (3.1, 3.2) operable to generate an output signal (SO,1, SO,2) from at least one input signal (SI,1, SI,2) and an electric-to-acoustic converter (5.1, 5.2), an input of which is operatively
connected to an output of the signal processing unit (3.1, 3.2) and which is operable
to supply an acoustic output signal to one ear of a user, each of the hearing instruments
further comprising a communication interface (7.1, 7.2) operable to exchange information
with the other hearing instrument associated with the other ear of the user, characterised in that the hearing instruments are programmed so as to be operable to detect, using the
communication interface, whether the other hearing instrument associated with the
other ear of the user is active, and to apply a first gain to the input signal (SI,1, SI,2) if the other hearing instrument is found to be active, or to apply a second gain
to the input signal (SI,1 SI,2) if the other hearing instrument is not found to be active.
9. A hearing instrument according to claim 8, wherein the communication interface (7.1,
7.2) is a wireless communication interface.
1. Verfahren zur Steuerung einer Verstärkungseinstellung eines Hörgeräts, wobei das Hörgerät
so betrieben werden kann, dass es aus mindestens einem Eingangssignal ein Ausgangsaudiosignal
ermittelt und dieses Ausgangsaudiosignal einem Ohr eines Benutzers bereitstellt, wobei
das Hörgerät eine Kommunikationsschnittstelle (7.1, 7.2) aufweist, welche so betrieben
werden kann, dass sie eine Kommunikationsverbindung zu einem weiteren Hörgerät aufbaut,
welches dem anderen Ohr des Benutzers zugeordnet ist,
dadurch gekennzeichnet, dass das Verfahren folgende Schritte aufweist:
Feststellen mittels der Kommunikationsschnittstelle, ob das weitere Hörgerät für das
andere Ohr des Benutzers aktiv ist;
Festlegung einer ersten Verstärkungseinstellung, wenn das weitere Hörgerät für das
andere Ohr des Benutzers aktiv ist; und
Festlegung einer zweiten Verstärkungseinstellung, welche sich von der ersten Verstärkungseinstellung
unterscheidet, wenn das weitere Hörgerät nicht aktiv ist.
2. Verfahren gemäß Anspruch 1, wobei ein mittlerer Verstärkungswert der ersten Verstärkungseinstellung
niedriger ist als ein mittlerer Verstärkungswert der zweiten Verstärkung.
3. Verfahren gemäß Anspruch 2, wobei die der zweiten Verstärkungseinstellung zugeordnete
Verstärkung der der ersten Verstärkungseinstellung zugeordneten Verstärkung, erhöht
um einen festen, eventuell frequenzabhängigen dB-Wert, entspricht.
4. Verfahren gemäß einem der vorhergehenden Ansprüche, wobei der Schritt des Feststellens,
ob ein weiteres Hörgerät aktiv ist, wiederholt in regelmäßigen oder zufälligen Zeitintervallen
ausgeführt wird.
5. Verfahren gemäß einem der vorhergehenden Ansprüche, wobei zur Feststellung, ob das
weitere Hörgerät, welches dem anderen Ohr des Benutzers zugeordnet ist, aktiv ist,
das Hörgerät ein Abfragesignal sendet, welches eine Statusinformation von dem eventuell
weiteren Hörgerät abfragt.
6. Verfahren gemäß einem der Ansprüche 1 bis 4, wobei für den Fall, dass das weitere
Hörgerät aktiv ist, dieses eine Statusinformation proaktiv zum Hörgerät sendet.
7. Verfahren gemäß einem der vorhergehenden Ansprüche, wobei mindestens einmalig ein
für den Benutzer wahrnehmbares Signal durch das immer noch aktive Hörgerät veranlasst
wird, wenn das weitere Hörgerät nicht aktiv ist.
8. System von Hörgeräten, welches zwei Hörgeräte aufweist, wobei jedes eine Signalverarbeitungseinheit
(3.1, 3.2) aufweist, welche so betrieben werden kann, dass sie ein Ausgangssignal
(SO,1, SO,2) aus zumindest einem Eingangssignal (SI,1, SI,2) generiert, sowie einen elektroakustischen Wandler (5.1, 5.2), dessen Eingang in
Wirkverbindung mit einem Ausgang der Signalverarbeitungseinheit (3.1, 3.2) steht,
und der so betreiben werden kann, dass er ein akustisches Ausgangssignal einem Ohr
des Benutzers bereitstellt, wobei jedes Hörgerät weiterhin eine Kommunikationsschnittstelle
(7.1, 7.2) aufweist, welche so betrieben werden kann, dass sie Informationen mit dem
anderen Hörgerät, welches dem anderen Ohr des Benutzers zugeordnet ist, austauschen
kann, dadurch gekennzeichnet, dass die Hörgeräte so programmiert sind, dass sie so betrieben werden können, dass sie
mittels der Kommunikationsschnittstelle detektieren können, ob das andere Hörgerät,
welches dem anderen Ohr des Benutzers zugeordnet ist, aktiv ist, und eine erste Verstärkung
auf das Eingangssignal (SI,1, SI,2) anwenden, wenn das andere Hörgerät aktiviert vorgefunden wird, oder eine zweite
Verstärkung auf das Eingangssignal (SI,1, SI,2) anwenden, wenn das andere Hörgerät nicht als aktiviert vorgefunden wird.
9. Hörgerät gemäß Anspruch 8, wobei die Kommunikationsschnittstelle (7.1, 7.2) eine drahtlose
Kommunikationsschnittstelle ist.
1. Procédé de contrôle du réglage du gain d'un instrument auditif, l'instrument auditif
pouvant être utilisé pour définir un signal audio de sortie à partir d'au moins un
signal d'entrée et pour délivrer ledit signal audio de sortie dans une oreille d'un
utilisateur, l'instrument auditif comprenant une interface de communication (7.1,
7.2) qui peut être utilisée pour établir une liaison de communication avec un autre
instrument auditif associé à l'autre oreille de l'utilisateur, caractérisé en ce que le procédé comprend les étapes qui consistent à déterminer à l'aide de l'interface
de communication si l'autre instrument auditif prévu pour l'autre oreille de l'utilisateur
est actif, à adopter un premier réglage du gain si l'autre instrument auditif destiné
à l'autre oreille de l'utilisateur est actif et à adopter un deuxième réglage du gain
différent du premier réglage du gain si l'autre instrument auditif n'est pas actif.
2. Procédé selon la revendication 1, dans lequel la valeur moyenne du gain du premier
réglage de gain est inférieure à la valeur moyenne du gain du deuxième réglage de
gain.
3. Procédé selon la revendication 2, dans lequel le gain du deuxième réglage de gain
correspond au gain du premier réglage de gain augmenté d'une valeur en dB fixe et
éventuellement dépendante de la fréquence.
4. Procédé selon l'une quelconque des revendications précédentes, dans lequel l'étape
qui consiste à déterminer si un autre instrument auditif est actif est exécutée à
répétition à des intervalles de temps réguliers ou aléatoires.
5. Procédé selon l'une quelconque des revendications précédentes, dans lequel pour déterminer
si l'autre instrument auditif associé à l'autre oreille de l'utilisateur est actif,
l'instrument auditif envoie un signal de requête qui demande une information de statut
à l'autre instrument auditif éventuellement présent.
6. Procédé selon l'une quelconque des revendications 1 à 4, dans lequel, si l'autre instrument
auditif est actif, il envoie proactivement une information de statut à l'instrument
auditif.
7. Procédé selon l'une quelconque des revendications précédentes, dans lequel un signal
perceptible par l'utilisateur est émis au moins une fois par l'accessoire auditif
encore actif lorsque l'autre instrument auditif n'est pas actif.
8. Système d'instruments auditifs qui comprend deux instruments auditifs qui comprennent
chacun une unité (3.1, 3.2) de traitement de signaux utilisés pour émettre un signal
de sortie (SO,1, SO,2) à partir d'au moins un signal d'entrée (SI,1, SI,2) et un convertisseur électrique-acoustique (5.1, 5.2) dont une entrée est reliée
fonctionnellement à une sortie de l'unité (3.1, 3.2) de traitement de signaux et qui
peut être utilisée pour délivrer un signal acoustique de sortie dans une oreille d'un
utilisateur, chacun des instruments auditifs comprenant en outre une interface de
communication (7.1, 7.2) qui peut être utilisée pour échanger des informations avec
l'autre instrument auditif associé à l'autre oreille de l'utilisation, caractérisé en ce que les instruments auditifs sont programmés de manière à pouvoir détecter à l'aide de
l'interface de communication si l'autre instrument auditif associé à l'autre oreille
de l'utilisateur est actif, à appliquer sur le signal d'entrée (SI,1, SI,2) un premier gain si l'autre instrument auditif s'avère être actif et à appliquer
un deuxième gain au signal d'entrée (SI,1, SI,2) si l'autre instrument auditif s'avère ne pas être actif.
9. Instrument auditif selon la revendication 8, dans lequel l'interface de communication
(7.1, 7.2) est une interface de communication sans fil.


REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description