FIELD OF INVENTION
[0001] The present invention relates to hearing aids, especially binaural hearing aids,
               configured for wireless communication and having wireless communication properties,
               and more specifically to binaural hearing aids capable of adaptively matching an antenna
               to the environment by detecting a signal strength of a received and/or transmitted
               signal and adjusting antenna properties accordingly.
 
            BACKGROUND
[0002] Hearing aids are very small and delicate devices and comprise many electronic and
               metallic components contained in a housing small enough to fit in the ear canal of
               a human or behind the outer ear. The many electronic and metallic components in combination
               with the small size of the hearing aid housing impose high design constraints on radio
               frequency antennas to be used in hearing aids with wireless communication capabilities.
 
            [0003] Conventionally, antennas in hearing aids have been used for receiving radio broadcasts
               or commands from a remote control. Typically, such antennas are designed to fit in
               the hearing aid housing without special concern with relation to the efficiency of
               the antenna.
 
            [0004] It is known in the art to provide matching circuitry for antennas, and also for antennas
               used in hearing aids. The matching circuitry may match the impedance of the antenna
               to the applicable radio or transceiver used and may optimise the effective length
               of the antenna to the frequency of the radio or transceiver. The matching is typically
               performed upon initial fitting of the hearing aid, or as disclosed in 
US2009/0196444, upon replacement of antenna conductors which may vary in for example length from
               one to another.
 
            [0005] WO 2009/156879 A1 describes method of tuning an antenna is provided, wherein the method comprises receiving
               a first signal strength indicator indicating a signal strength of a first data signal
               transmitted by an antenna on a first frequency, receiving a second signal strength
               indicator indicating a signal strength of a second data signal transmitted by the
               antenna on a second frequency different to the first frequency, determining a tuning
               control signal based on the first signal strength indicator and the second signal
               strength indicator, and tuning the antenna based on the control signal.
 
            [0006] US 2004/037442 A1 describes a wireless binaural hearing aid system that utilises direct sequence spread
               spectrum technology to synchronise operation between individual hearing prostheses
               is provided.
 
            SUMMARY
[0007] It is an objective of the present invention to provide a hearing aid, such as a binaural
               hearing aid, providing an adaptive matching for a hearing aid antenna, such as providing
               an adaptive matching in response to detection of a received signal strength.
 
            [0008] According to a first aspect of the present invention, a binaural hearing aid comprising
               a first hearing aid and a second hearing aid is provided, each hearing aid comprising
               a microphone for reception of sound and conversion of the received sound into a corresponding
               first audio signal, a signal processor for processing the first audio signal into
               a second audio signal compensating a hearing loss of a user of the hearing aid, a
               wireless communications unit connected to the signal processor for wireless communication
               and being interconnected with an antenna for emission and/or reception of an electromagnetic
               field. The first hearing aid and/or the second hearing aid have/has an adjustable
               antenna matching mechanism configured to receive information on a detected signal
               strength and configured to adaptively adjust the matching mechanism to optimize antenna
               reception/emission according to the detected signal strength.
 
            [0009] The first hearing aid and/or the second hearing aid may have a detector connected
               to the wireless communications unit, and the detector may be configured to detect
               a signal strength of a communications signal received or transmitted through the wireless
               communications unit.
 
            [0010] Alternatively, a hearing aid accessory may comprise the detector and information
               on the detected signal strength may be provided to the adjustable antenna matching
               mechanism for example via the wireless communications unit. Furthermore, a hearing
               aid fitting system may comprise the detector and information on the detected signal
               strength may be provided to the adjustable antenna matching mechanism for example
               via the wireless communications unit.
 
            [0011] In another aspect of the present invention, a hearing aid is provided, the hearing
               aid having a microphone for reception of sound and conversion of the received sound
               into a corresponding first audio signal, a signal processor for processing the first
               audio signal into a second audio signal compensating a hearing loss of a user of the
               hearing aid, a wireless communications unit connected to the signal processor for
               wireless data communication and being interconnected with an antenna for emission
               and/or reception of an electromagnetic field. The hearing aid further comprises an
               antenna matching mechanism configured to receive information on a detected signal
               strength from a detector and adaptively control the antenna matching mechanism to
               optimize antenna reception according to the detected signal strength of the received
               signal. The hearing aid may further comprise the detector, and the detector may be
               connected to the wireless communications unit. The detector is configured to detect
               a signal strength of a signal received or transmitted through the wireless communications
               unit.
 
            [0012] According to a further aspect of the present invention, a method of matching a hearing
               aid antenna in a binaural hearing aid in accordance with a detected signal strength
               of a received communications signal is provided. The binaural hearing aid having a
               first hearing aid to be positioned at one ear of a user and a second hearing aid to
               be positioned at another ear of the user, the method comprising receiving a communications
               signal by a wireless communications unit in the first hearing aid, detecting a signal
               strength of the received communications signal, adaptively adjust a matching mechanism
               positioned in the first hearing aid and/or the second hearing aid to obtain optimized
               antenna reception and/or transmission according to the detected signal strength, such
               as in response to the detected signal strength.
 
            [0013] According to a still further aspect of the present invention, a method of adaptively
               matching a hearing aid antenna to optimize a received communications signal strength
               is provided. The method comprises detecting the signal strength of a received communications
               signal, adaptively adjust a hearing aid antenna matching mechanism to optimize received
               communications signal strength.
 
            [0014] The communications signal may be transmitted from the second hearing aid to the first
               hearing aid for detection, thus the communications signal received in one hearing
               aid of a binaural hearing aid may be received from another of the hearing aids of
               the binaural hearing aid.
 
            [0015] In one or more embodiments the communications signal received through the wireless
               communications unit in one hearing aid is a signal transmitted from the other of the
               first and second hearing aids in a binaural hearing aid. Thus, the signal strength
               of a signal received from the second hearing aid may be detected.
 
            [0016] It is envisaged that the adaptive adjustment may be performed during a fitting procedure
               fitting the hearing aid to a user, or the adaptive adjustment may be performed during
               use of the hearing aid.
 
            [0017] The received signal strength may be an indication of the power level of the communications
               signal received by the antenna. The signal strength may be detected or measured according
               to any known methods, including for example measuring using a detector comprising
               received signal strength indicator (RSSI) circuitry, received channel power indicator
               (RCPI) circuitry, etc. Furthermore, also the signal noise ratio (SNR) may be measured.
 
            [0018] The signal strength of the received signal may be detected or measured in the hearing
               aid, such as by a detector provided in the hearing aid, such as in the first hearing
               aid of a binaural hearing aid having a first and a second hearing aid. In some embodiments
               the detector may form part of the wireless communications unit, such as part of a
               radio.
 
            [0019] A controller for controlling the matching circuit may be provided, such as provided
               in the wireless communications unit.
 
            [0020] An adjustable antenna matching mechanism provided in the hearing aid, or in the first
               hearing aid and/or the second hearing aid of a binaural hearing aid, is configured
               to receive information on the detected signal strength and configured to adaptively
               adjust the matching mechanism to optimize antenna reception/emission according to
               the detected signal strength.
 
            [0021] Alternatively, the signal strength of a signal transmitted from the hearing aid to
               e.g. an accessory device, or to a hearing aid fitting system, may be detected in the
               accessory device or in the hearing aid fitting system, respectively, and information
               on the transmitted signal strength may be provided to an adjustable antenna matching
               mechanism provided in the hearing aid, the adjustable antenna matching mechanism being
               configured to adaptively adjust the matching mechanism to optimize antenna reception/emission
               according to the detected signal strength.
 
            [0022] The antenna matching mechanism may be configured to adjust an impedance of the antenna
               matching mechanism to optimize antenna reception.
 
            [0023] The antenna matching mechanism may be a closed adaptive matching loop using a variable
               inductance in the matching circuitry. It is envisaged that the impedance may be adjusted
               according to a predetermined list of values, or that the impedance may be iteratively
               adjusted until an optimized antenna reception/transmission is obtained.
 
            [0024] The adjustable antenna matching mechanism may be configured to iteratively adjust
               the antenna matching mechanism until an end-adjustment criteria is reached, and the
               adjustable antenna matching mechanism may be configured to adjust the antenna matching
               mechanism upon receiving a detected signal strength being less than a predetermined
               threshold. The adjustable antenna matching mechanism may be configured to iteratively
               adjust the antenna matching mechanism until an end-adjustment criteria being the reception
               of a detected signal strength above the predetermined threshold is reached.
 
            [0025] It is an advantage of the present invention that it is possible to control the field
               distribution of the antenna by adaptively adjusting the antenna matching mechanism
               taking into account different antenna structures, different antenna environments,
               etc.
 
            [0026] It is envisaged that the signal strength may be detected remotely, that is for example
               either in an accessory device, in a hearing aid fitting system, or in one of the first
               and second hearing aids of a binaural hearing aid, etc. Subsequently, either information
               on the detected signal strength, such as a received signal strength indicator may
               be transmitted to the hearing aid, such as to the other of the first and second hearing
               aids of a binaural hearing aid or adjustment parameters may be provided to the hearing
               aid, such as to the other of the first and second hearing aid of a binaural hearing
               aid. The adjustment parameters may comprise impedance values, such as capacitor values,
               conductance values, etc.
 
            [0027] In one or more embodiments, the detector is configured to detect the signal strength
               upon triggering to adaptively adjust the matching mechanism to optimize antenna reception.
               The detector may be triggered by hearing aid adjustments, such as program selections,
               environmental changes, etc.
 
            [0028] The hearing aid adjustments may be performed automatically, without direct interaction
               from a user.
 
            [0029] The wireless communications unit is configured for wireless data communication, and
               in this respect interconnected with the antenna for emission and reception of an electromagnetic
               field. The wireless communications unit may comprise a transmitter, a receiver, a
               transmitter-receiver pair, such as a transceiver, a radio unit, etc. The wireless
               communications unit may be configured for communication using any protocol as known
               for a person skilled in the art, including Bluetooth, WLAN standards, manufacture
               specific protocols, such as tailored proximity antenna protocols, such as proprietary
               protocols, such as low-power wireless communication protocols, etc.
 
            [0030] The wireless communications unit interconnected with the antenna may be configured
               for operation in the ISM frequency band. The wireless communications unit interconnected
               with the antenna may be configured for operation at a frequency of at least 100 MHz,
               such as at a frequency of at least 800 MHz, such as at at least 1 GHz, such as at
               a frequency between 1.5 GHz and 3 GHz, such as at a frequency of 2.4 GHz, such as
               at substantially 2.4 GHz.
 
            [0031] The wireless communications unit may be configured for communication with external
               devices, such as hearing aid accessories, such as remote controls, telephones, such
               as mobile telephones, televisions, television boxes, television streamer boxes, spouse
               microphones, hearing aid fitting systems, etc.
 
            [0032] The wireless communications unit may also be configured for communication with another
               hearing aid in a binaural hearing aid, so that data may be exchanged between the hearing
               aid positioned at the right ear of a user and the hearing aid positioned at the left
               ear of the user. Such binaural communication may be used for example for binaural
               beam forming, for binaural noise reduction, etc.
 
            [0033] The hearing aid may further comprise an attachment member, such as an attachment
               member transmitting the second audio signal from the hearing aid housing to the ear
               of a user when the hearing aid is worn in its intended operational position and wherein
               at least a part of the antenna extends via the attachment member.
 
            [0034] The antenna, or at least the part of the antenna extending via the attachment member,
               may have a length being correlated with a length of the attachment member. The antenna,
               or at least the part of the antenna extending via the attachment member, may have
               substantially a same length as the attachment member. Alternatively, the antenna,
               or at least the part of the antenna extending via the attachment member, may have
               substantially a same length irrespective of the length of the attachment member.
 
            [0035] The attachment member may be an electrical connection to a receiver in the ear of
               a user, a sound tube, such as a thin tube configured for acoustic wave propagation,
               or an ear hook, such as an ear hook for holding the hearing aid in a desired position
               around the ear of a user.
 
            [0036] The attachment member may be any attachment member configured to be attached to the
               hearing aid, such as to a hearing aid housing. The attachment member may be a holding
               member for holding the hearing aid in place during use, the attachment member may
               be configured to transmit the second audio signal from the hearing aid housing to
               the ear of a user, etc.
 
            [0037] The length of the attachment member may be determined by the size of a user's ear
               to allow for a smooth fitting, and may for example be selected during fitting of the
               hearing aid. The length of an attachment member varies depending on the type of attachment
               member provided. For some attachment members, e.g. for attachment members for sound
               transmission, the length of the attachment members may typically range from about
               50 mm to about 70 mm, and the attachment members are typically available in a number
               of predetermined lengths. As the attachment members are exposed to the environment,
               including the user's head, the material may degrade overtime, and typically need to
               be exchanged at regular intervals. As the length may vary from one attachment member
               to another attachment member, that is, either the length of the attachment member
               and/or the length of the part of the antenna extending via the attachment member may
               vary, an adaptively adjustable matching mechanism ensures that the field distribution
               of the antenna is substantially unchanged.
 
            [0038] It is an advantage of being able to maintain a constant field distribution of the
               antenna especially to maintain a constant ear-to-ear performance of a binaural hearing
               aid.
 
            [0039] Especially for binaural hearing aids, the performance of the ear-to-ear link, that
               is the wireless communication between a first hearing aid and a second hearing aid
               in a binaural hearing aid, is crucial for optimum operation, such as for synchronization
               between the first and second hearing aids to e.g. achieve sound localization, and
               for e.g. noise reduction.
 
            [0040] To obtain the best possible ear-to-ear link, there are basically two methods, either
               to increase the power in the ear-to-ear link or increase the size of the antenna.
               It is not desirable to increase the power in the ear-to-ear link due to the conflicting
               need to increase battery lifetime, and the size of the antenna is typically limited
               by the hearing aid dimensions.
 
            [0041] In one or more embodiments, the hearing aids have an attachment element and the antenna
               extend at least partly into the attachment element. The attachment element may have
               a variable length as discussed above depending on e.g. the size of a user's head.
               To optimize the performance of the ear-to-ear link, the antenna may be as long as
               possible, and thus for a user having a larger size, i.e. longer, attachment element
               also the size of the antenna may be increased. As the field distribution on the antenna
               is an important factor in ear-to-ear communication, there is a need to control the
               field distribution. The field distribution may be controlled in that the length of
               the antenna element extending at least partly into the attachment element is kept
               constant irrespective of the length of the attachment element. However, in order to
               take advantage of the longer attachment elements, the antenna element may extend further
               into a longer attachment element. The length of the antenna element extending into
               the attachment element may for example correspond to, such as correspond substantially
               to, the length of the attachment element.
               To control the field distribution on antenna elements having different lengths, a
               matching mechanism may be provided, and the field distribution may be controlled by
               adjusting the matching mechanism according to the length of the attachment member
               or antenna used. To enable adaptive matching of the matching mechanism, the hearing
               aid may comprise a detector configured to detect a signal strength of a communications
               signal received through the wireless communications unit and adjust the matching mechanism
               in response hereto, e.g. by providing a closed adaptive matching loop. Thereby, the
               field distribution on the antenna may be controlled and the different lengths of the
               attachment members may be accounted for. Hereby, the binaural efficiency may be increased
               when the length of the attachment member used is increased.
 
            [0042] It is envisaged that features and characteristics described in connection with one
               aspect of the invention are applicable to other aspects mutatis mutandis.
 
            [0043] The present invention will now be described more fully hereinafter with reference
               to the accompanying drawings, in which exemplary embodiments of the invention are
               shown. The invention may, however, be embodied in different forms and should not be
               construed as limited to the embodiments set forth herein. Rather, these embodiments
               are provided so that this disclosure will be thorough and complete, and will fully
               convey the scope of the invention to those skilled in the art. Like reference numerals
               refer to like elements throughout. Like elements will, thus, not be described in detail
               with respect to the description of each figure.
 
            BRIEF DESCRIPTION OF THE DRAWINGS
[0044] 
               
               Fig. 1 shows schematically a hearing aid,
               Fig 2 shows schematically a binaural hearing aid having a detector in one hearing
                  aid of the binaural hearing aid and an adaptively adjustable antenna matching mechanism
                  in another of the hearing aids of the binaural hearing aid,
               Fig. 3a shows a hearing aid communicating with a hearing aid fitting system, wherein
                  the hearing aid fitting system comprises a detector,
               Fig. 3b shows a hearing aid communicating with a hearing aid accessory, wherein the
                  hearing aid accessory comprises a detector,
               Figs. 4a-d show schematically various attachment member lengths having different antenna
                  lengths.
               Fig. 5 shows a flow chart illustrating a method of adaptively adjusting an antenna
                  matching mechanism in a hearing aid,
               Fig. 6 shows a flow chart illustrating a method of adaptively adjusting an antenna
                  matching mechanism in a binaural hearing aid.
 
            DETAILED DESCRIPTION OF THE DRAWINGS
[0045] In Fig. 1, a hearing aid 100 is shown schematically. The hearing aid has a microphone
               160 for reception of sound and conversion of the received sound into a corresponding
               first audio signal, a signal processor 150 for processing the first audio signal into
               a second audio signal compensating a hearing loss of a user of the hearing aid, a
               speaker 170 for providing sound to a user, a wireless communications unit 130 connected
               to the signal processor 150 for wireless data communication and being interconnected
               with an antenna 110 for emission and/or reception of an electromagnetic field. The
               wireless communications unit may be a radio, such as a radio, such as a multi protocol
               radio, such as a radio supporting Bluetooth as well as proprietary wireless protocols.
               The hearing aid further has a detector 180 connected to the wireless communications
               unit 130. The detector is configured to detect a signal strength of a signal received
               through the wireless communications unit 130. An antenna matching mechanism 190 is
               configured to receive the detected signal strength from the detector 180 and adaptively
               control the matching mechanism 190 to optimize antenna reception according to the
               detected signal strength of the received signal. The detected signal strength may
               be provided to the antenna matching mechanism as a control signal. The hearing aid
               may have an attachment element 120 and the antenna 110 may extend into the attachment
               element 120.
 
            [0046] In some embodiment, the antenna matching mechanism may comprise, or consist of, a
               variable capacitor. The variable capacitor may form part of a matching circuitry for
               the antenna, such as a matching circuitry configured to match the antenna impedance
               to the radio, typically at 50 Ω.
 
            [0047] Fig. 2 shows a binaural hearing aid, each of the first and second hearing aids 121,
               122 has a microphone 161, 162, a signal processor 151, 152, speaker 171, 172, a wireless
               communications unit 131, 132 connected to the signal processor 151, 152 for wireless
               data communication and being interconnected with antenna 111, 112 for emission and/or
               reception of an electromagnetic field.
 
            [0048] The first and second hearing aids 121, 122 are configured to communicate with each
               other via wireless link 200 established between wireless communications units 131,
               132 via antennas 111, 112. The first hearing aid 121 further has a detector 181 connected
               to the wireless communications unit 130. The detector 181 may be an RSSI detector
               and is in the present example provided in the wireless communications unit 131. The
               detector is configured to detect a signal strength of a signal received through the
               wireless communications unit 131. The signal is in this embodiment received from the
               second hearing aid 122 via the wireless link 200. The antenna matching mechanism 192
               is thereby adaptively controlled to optimize antenna transmission according to the
               detected signal strength of the signal as received in the first hearing aid 121. Thus,
               information of the received signal strength is communicated from the detector 181
               to the antenna matching mechanism 192, such as to an antenna matching controller configured
               to control the matching parameters for the antenna matching mechanism. The matching
               parameters may comprise inductance and capacitance of a matching circuitry in the
               antenna matching mechanism.
 
            [0049] Even though speakers 170, 171, 172 are exemplary shown in the figures, it is envisaged
               that the hearing aid also may be a receiver in the ear type hearing aid, wherein the
               second signal is provided via an electrical connector in attachment member 120 (not
               shown in Fig. 2) to the ear 201, 202. When the receiver is provided in the hearing
               aid, such as in a behind the ear type hearing aid, the sound is typically transmitted
               to the ear 201, 202 via an attachment member comprising at least a sound tube.
 
            [0050] In Fig. 3a, a hearing aid 300 is shown schematically, and it is seen that the hearing
               aid 300 has an adjustable antenna matching mechanism 380 configured to receive information
               on a detected signal strength and being configured to adaptively adjust the matching
               mechanism 380 to optimize antenna reception/emission according to the detected signal
               strength. The detector 391 is in the present example provided in a hearing aid fitting
               apparatus 315, and information of the signal strength is provided to the hearing aid
               300 and thus, the matching mechanism is adjusted during fitting of the hearing aid.
               The fitting apparatus 315 and the hearing aid may communicate wirelessly and/or via
               a wired connection 320.
 
            [0051] Fig. 3b shows hearing aid 300 connected to a hearing aid remote control 325 and the
               hearing aid remote control 325 may comprise the detector 392. The hearing aid matching
               mechanism may be adjusted via the remote control 325.
 
            [0052] It is envisaged that any other hearing aid accessory may comprise a wireless communications
               unit and a detector to enable feedback on the information of the signal strength to
               the hearing aid. Typically, the hearing aid accessory and the hearing aid communicates
               via a hearing aid protocol, such as a proprietary protocol, using a wired or a wireless
               connection.
 
            [0053] Figs. 4a-d show variable lengths of antenna elements 411, 412, 413, 414 extending
               in attachment members 421, 422, 423, 424 of different lengths.
 
            [0054] The length of the attachment member is typically determined by the size of a user's
               head and/or ear to allow for a smooth fitting, and may for example be selected during
               fitting of the hearing aid. The length of an attachment member varies depending on
               the type of attachment member provided. For example, the length of attachment members
               for sound transmission typically range from about 50 mm to about 70 mm, and the attachment
               members may be available in a number of predetermined lengths. As the attachment members
               are exposed to the environment, including the user's head, the material may degrade
               over time, and typically need to be exchanged at regular intervals. As the length
               may vary from one attachment member to another attachment member, that is, either
               the length of the attachment member and/or the length of the part of the antenna extending
               via the attachment member, an adaptively adjustable matching mechanism ensures that
               the field distribution of the antenna is substantially unchanged.
 
            [0055] It is envisaged that the antenna elements 411, 412, 413, 414 extending into the attachment
               member may have a length being correlated with the attachment member length, and thus
               correlated with the size of a user's ear. The length of the antenna elements 411,
               412, 413, 414 may substantially be corresponding to the attachment member length,
               however, the length of the antenna element 411, 412, 413, 414 may also be shorter
               than the attachment member, such as 30% shorter, such as 20 %, such as 10 % shorter,
               such as 5 % shorter than the attachment member.
               
               
Table 1 below shows exemplary lengths of the attachment members for an attachment
                  member being a sound tube.
                  
                     
                        
                           
                           
                        
                        
                           
                              | Tube name | length (mm) | 
                        
                        
                           
                              | -1B | 52.1 | 
                           
                              | 0A | 57,9 | 
                           
                              | 0B | 55,0 | 
                           
                              | 1A | 60,0 | 
                           
                              | 1B | 57,9 | 
                           
                              | 2A | 67,0 | 
                           
                              | 2B | 64,0 | 
                           
                              | 3A | 72,0 | 
                           
                              | 3B | 69,0 | 
                        
                     
                   
                
            [0056] In Fig. 5, a flowchart illustrates a method of adaptively matching a hearing aid
               antenna to optimize a received communications signal strength. The method comprises
               detecting the signal strength of a received communications signal, provide the detected
               signal strength, such as a control signal comprising information about the signal
               strength, to an antenna matching mechanism, and adaptively adjust a hearing aid antenna
               matching mechanism to optimize received communications signal strength.
 
            [0057] In Fig. 6, a flowchart illustrates a method 600 of adaptively matching hearing aid
               antenna(s) in a binaural hearing aid. Especially for binaural hearing aids, the performance
               of the ear-to-ear link 200, that is the wireless communication between a first hearing
               aid 121 and a second hearing aid 122 in a binaural hearing aid, is crucial for optimum
               operation, such as for synchronization between the first and second hearing aids 121,
               122 to e.g. achieve sound localization, and for e.g. noise reduction.
 
            [0058] The method 600 matches a hearing aid antenna 111,112 in a binaural hearing aid in
               accordance with a detected signal strength of a received communications signal. The
               method 600 comprises the steps of in a binaural hearing aid 601, transmitting a communications
               signal from one hearing aid in step 602, receiving the transmitted communications
               signal by a wireless communications unit in the other hearing aid in step 603, detecting
               a signal strength of the received communications signal in step 604, for example using
               a detector, such as an RSSI detector and provide the detected signal strength to an
               antenna matching mechanism to optimize received communications strength, such as in
               the ear-to-ear communication.
 
            [0059] It is from the current description and the drawings envisaged that the detector and
               the matching mechanism may be provided in a same hearing aid, in a same binaural hearing
               aid, each in one or the other hearing aid in a binaural hearing aid, providing the
               antenna matching mechanism in a hearing aid and the detector in an accessory, such
               as in an accessory device, and any combination thereof. In embodiments wherein the
               detector and the antenna matching mechanism are provided separately, information about
               the detected signal strength may be fed back to the antenna matching mechanism either
               via a wireless communication connection or via a wired connection. The information
               about the detected signal strength may be provided in the form of a control signal,
               or the received signal strength may be provided as an indication of the power level
               being received by the antenna in connection with the detector, as an "above" or "below"
               threshold indication, and in any other way as known to a person skilled in the art.
 
            [0060] Although particular embodiments of the present inventions have been shown and described,
               it will be understood that it is not intended to limit the claimed inventions to the
               preferred embodiments, and it will be obvious to those skilled in the art that various
               changes and modifications may be made without departing from the scope of the claimed
               inventions. The specification and drawings are, accordingly, to be regarded in an
               illustrative rather than restrictive sense. The claimed inventions are intended to
               cover alternatives, modifications, and equivalents.
 
            [0061] Embodiments of the invention are described in the following list of enumerated items:
               
               
                  - 1. A binaural hearing aid comprising a first hearing aid (121) and a second hearing
                     aid (122), each hearing aid (121, 122) comprising
                     
                     a microphone (161, 162) for reception of sound and conversion of the received sound
                        into a corresponding first audio signal, a signal processor (151, 152) for processing the first audio signal into a second
                        audio signal compensating a hearing loss of a user of the hearing aid, a wireless communications unit (131, 132) connected to the signal processor (151,
                        152) for wireless communication and being interconnected with an antenna (111, 112)
                        for emission and/or reception of an electromagnetic field, the first hearing aid (121) having a detector (181) connected to the wireless communications
                     unit (131), the detector (181) being configured to detect a signal strength of a communications
                     signal received through the wireless communications unit (131), and
 the first hearing aid (121) and/or the second hearing aid (122) having an adjustable
                     antenna matching mechanism (192) configured to receive information on the detected
                     signal strength and adjust the matching mechanism (192) to optimize antenna (111,
                     112) reception/emission according to the detected signal strength of the received
                     communications signal.
- 2. A binaural hearing aid according to item 1, wherein the communications signal received
                     through the wireless communications unit (131) in one hearing aid (121) is a signal
                     transmitted from the other of the first and second hearing aids (122).
- 3. A binaural hearing aid according to any of the previous items, wherein the signal
                     strength is measured using a receive signal strength indicator (RSSI) circuit.
- 4. A binaural hearing aid according to any of the previous item, wherein the hearing
                     aid further comprises an attachment member (120) transmitting the second audio signal
                     from the hearing aid housing to the ear of a user when the hearing aid is worn in
                     its intended operational position and wherein at least a part of the antenna (111,
                     112) extends via the attachment member (120).
- 5. A binaural hearing aid according to item 4, wherein a length of the antenna (111,
                     112) is correlated with a length of the attachment member (120).
- 6. A binaural hearing aid according to any of item s 4-5, wherein the attachment member
                     (120) is an electrical connection to a receiver in the ear of a user, a sound tube
                     or an ear hook.
- 7. A binaural hearing aid according to any of the previous items, wherein the signal
                     strength of the received signal is detected during a hearing aid fitting procedure.
- 8. A binaural hearing aid according to any of the previous items, wherein the detector
                     is configured to detect the signal strength upon triggering to adaptively adjust the
                     matching mechanism to optimize antenna reception.
- 9. A binaural hearing aid according to item 8, wherein the detector (181) is triggered
                     by hearing aid adjustments, such as program selection.
- 10. A binaural hearing aid according to any of the previous items, wherein an impedance
                     of the antenna matching mechanism (192) is adjusted to optimize antenna reception.
- 11. A binaural hearing aid according to any of the previous items, wherein the adjustable
                     antenna matching mechanism (192) is configured to iteratively adjust the antenna matching
                     mechanism (192) until an end-adjustment criteria is reached.
- 12. A binaural hearing aid according to any of the previous items, wherein the adjustable
                     antenna matching mechanism (192) is configured to adjust the antenna matching mechanism
                     (192) upon receiving a detected signal strength being less than a predetermined threshold.
- 13. A binaural hearing aid according to item 12, wherein the adjustable antenna matching
                     mechanism (192) is configured to iteratively adjust the antenna matching mechanism
                     (192) until an end-adjustment criteria being the reception of a detected signal strength
                     above the predetermined threshold is reached.
- 14. A method of matching a hearing aid antenna in a binaural hearing aid in accordance
                     with a detected signal strength of a received communications signal, the binaural
                     hearing aid having a first hearing aid (121) to be positioned at one ear of a user
                     and a second hearing aid (122) to be positioned at another ear of the user, the method
                     comprising
 receiving the communications signal by a wireless communications unit (131) in the
                     first hearing aid (121),
 detecting a signal strength of the received communications signal,
 control a matching mechanism positioned in the first hearing aid (121) and/or the
                     second hearing aid (122) to obtain optimized antenna reception and/or transmission
                     according to the detected signal strength.
- 15. A method according to item 14, wherein the communications signal is transmitted
                     from the second hearing aid (122) to the first hearing aid (121).
 
          
         
            
            1. A hearing aid (121) comprising
               
               
a microphone (161) for reception of sound and conversion of the received sound into
                  a corresponding first audio signal,
               
               a signal processor (151) for processing the first audio signal into a second audio
                  signal compensating a hearing loss of a user of the hearing aid,
               
               a wireless communications unit (131) connected to the signal processor (151) for wireless
                  communication and being interconnected with an antenna (111) for emission and/or reception
                  of an electromagnetic field, the antenna (111) being configured for operation at a
                  frequency of at least 800 MHz,
               the hearing aid (121) having an adjustable antenna matching mechanism (192) configured
               to receive information on a detected signal strength and adjust the matching mechanism
               (192) to optimize antenna (111) reception/emission according to the detected signal
               strength of the received communications signal. 
 
            2. A binaural hearing aid according to claim 1, wherein the hearing aid (121) has a
               detector (181) connected to the wireless communications unit (131), the detector (181)
               being configured to detect a signal strength of a communications signal received through
               the wireless communications unit (131).
 
            3. A binaural hearing aid according to any of the previous claims, wherein the signal
               strength is measured using a receive signal strength indicator (RSSI) circuit.
 
            3. A hearing aid according to any of the previous claims, wherein the hearing aid further
               comprises an attachment member (120) transmitting the second audio signal from a hearing
               aid housing to the ear of a user when the hearing aid is worn in its intended operational
               position and wherein at least a part of the antenna (111) extends via the attachment
               member (120).
 
            5. A hearing aid according to claim 4, wherein a length of the antenna (111) is correlated
               with a length of the attachment member (120).
 
            6. A hearing aid according to any of claims 4-5, wherein the attachment member (120)
               is an electrical connection to a receiver in the ear of a user, a sound tube or an
               ear hook.
 
            7. A hearing aid according to any of the previous claims, wherein the signal strength
               of the received signal is detected during a hearing aid fitting procedure.
 
            8. A hearing aid according to any of the previous claims, wherein the detector is configured
               to detect the signal strength upon triggering to adaptively adjust the matching mechanism
               to optimize antenna reception, preferably wherein the detector (181) is triggered
               by hearing aid adjustments, such as program selection.
 
            9. A hearing aid according to any of the previous claims, wherein an impedance of the
               antenna matching mechanism (192) is adjusted to optimize antenna reception.
 
            10. A hearing aid according to any of the previous claims, wherein the adjustable antenna
               matching mechanism (192) is configured to iteratively adjust the antenna matching
               mechanism (192) until an end-adjustment criteria is reached.
 
            11. A hearing aid according to any of the previous claims, wherein the adjustable antenna
               matching mechanism (192) is configured to adjust the antenna matching mechanism (192)
               upon receiving a detected signal strength being less than a predetermined threshold.
 
            12. A hearing aid according to claim 11, wherein the adjustable antenna matching mechanism
               (192) is configured to iteratively adjust the antenna matching mechanism (192) until
               an end-adjustment criteria being the reception of a detected signal strength above
               the predetermined threshold is reached.
 
            13. A method of matching a hearing aid antenna in a hearing aid in accordance with a
               detected signal strength of a received communications signal, the hearing aid having
               a first hearing aid (121) to be positioned at one ear of a user, the method comprising
               receiving the communications signal by a wireless communications unit (131) in the
               first hearing aid (121) or in a hearing aid accessory or in a hearing aid fitting
               system,
               detecting a signal strength of the received communications signal,
               control a matching mechanism positioned in the first hearing aid (121) to obtain optimized
               antenna reception and/or transmission according to the detected signal strength, wherein
               the antenna reception/transmission is configured for operation at a frequency of at
               least 800 MHz.
 
            14. A method according to claim 13, wherein the communications signal is transmitted
               from a second hearing aid (122) to the first hearing aid (121).
 
            15. A method according to claim 13, wherein the method further comprises the step of
               providing information on the detected signal strength, to the adjustable antenna matching
               mechanism, via the wireless communications unit (131).