FIELD
[0001] The present disclosure relates to a hearing aid, such as a behind-the-ear hearing
aid, comprising a microphone configured to receive sound. The hearing aid comprises
a processing unit configured to provide a processed audio signal for compensating
a hearing loss of a user. More particularly, the hearing aid comprises a printed circuit
board comprising a first layer. The hearing aid comprises an antenna provided as an
electrically conducting material on the first layer.
[0002] The hearing aid may be used in a binaural hearing aid system. During operation, the
hearing aid is worn in the ear of a user.
BACKGROUND
[0003] Hearing aids are very small and delicate devices and comprise many electronic and
metallic components contained in a housing or shell small enough to fit in the ear
canal of a human or be located behind the outer ear. The many electronic and metallic
components in combination with the small size of the hearing aid housing or shell
impose high design constraints on radio frequency antennas to be used in hearing aids
with wireless communication capabilities.
[0004] Moreover, the antenna in the hearing aid has to be designed to achieve a satisfactory
performance despite these limitations and other high design constraints imposed by
the size of the hearing aid.
[0005] The developments within wireless technologies for hearing devices and the continuous
efforts to make hearing devices smaller and more cost effective to manufacture has
led to the use of flexible carriers incorporating one or more antennas in hearing
devices.
[0006] Still further, in binaural hearing aid systems, the requirements to the quality of
the communication between the hearing aids in the binaural hearing aid system are
ever increasing, and include demands for low latency and low noise, increasing the
requests for effective antennas in the hearing aids.
SUMMARY
[0007] There is a desire for reducing the size of the electrical assembly of a hearing device.
[0008] There is a need for improved wireless communication in hearing aids.
[0009] It is an object of the present invention to provide a hearing aid with reduced size
of the electrical assembly of the hearing aid and with improved wireless communication
capabilities, such as improved wireless communication capabilities between two hearing
aids worn in or behind opposite ears of the user, and/or between a hearing aid and
an accessory device.
[0010] Radio connectivity between hearing aids (His) allows for advanced binaural signal
processing when the important ear-to-ear (E2E) link is ensured. Furthermore, the His
may be connected to a plethora of accessories, that can be either body-worn or placed
in the user's proximity, and hence to the internet as part of the so-called internet
of things (IoT). However, it is challenging but of key importance to ensure a stable
E2E link. The 2.4 GHz ISM band is preferred due to the presence of many harmonized
standards for low-power communications, such as BLE or ZigBee, its worldwide availability
for industrial use, and the trade-off between power consumption and range that can
be achieved. The E2E link is particularly demanding in terms of requirements on the
wearable antenna design and performance. In fact, in order to achieve a good on-body
performance, the antenna needs to exhibit optimal radiation efficiency, bandwidth,
polarization, and radiation pattern, while the volume available for the design is
extremely reduced, as most times space comes at a premium in wearable devices such
as in hearing aid, in particular in ITE hearing aids. Furthermore, mass production
and industrial design needs demand the antenna to be as well low-profile, lightweight,
and inexpensive to manufacture. In particular, the antenna polarization characteristic
is an important performance parameter. More overall constrains may also be relevant.
In fact, the efficiency may be seriously jeopardized by the proximity of the antenna
to the human head, as the body tissues have very high losses around 2.4 GHz due to
the high water content. This may critically impact the overall performance given the
magnitude of the drop in efficiency and the fact that the HI radios operate in ultra-low-power
regime. Another issue threatening antenna efficiency is the little volume available
for the design, as this necessarily brings the antenna in close physical, hence, electrical
as well, proximity of other parts of the device, with a strong likelihood of coupling
to them. A large bandwidth is as well hard to achieve for an electrically small antenna
(ESA), due to its fundamental limits. The bandwidth may cover at least the whole 2.4
GHz ISM band, but a larger bandwidth would help to compensate for the detuning of
the antenna caused by the body, that varies across users.
[0011] In accordance with the present disclosure, the above-mentioned and other objects
are obtained by a behind-the-ear hearing aid.
[0012] Disclosed is a hearing aid comprising a microphone configured to receive sound. The
hearing aid comprises a processing unit configured to provide a processed audio signal
for compensating a hearing loss of a user. The hearing aid comprises a printed circuit
board comprising a first layer. The hearing aid comprises an antenna provided as an
electrically conductive material on the first layer. The hearing aid comprises a wireless
communication unit for wireless communication. The hearing aid comprises a polarization
element configured for forming the polarization of the antenna, where the polarization
element is provided on a flexible printed circuit board, and where the flexible printed
circuit board comprises at least a first flexible printed circuit board.
[0013] The hearing aid may be a behind-the-ear (BTE) hearing aid. The hearing aid may comprise
a housing. The features of components of the hearing aid may be comprised, provided
or arranged in the housing.
[0014] The processing unit is configured to process the sound received by the microphone
to provide a processed audio signal for compensating a hearing loss of a user. The
hearing aid may also comprise an output transducer for providing an acoustic output,
i.e. the processed audio signal form the processing unit, to an ear of the user wearing
the hearing aid in or behind or at his/her ear.
[0015] The hearing aid comprises a printed circuit board comprising a first layer. The antenna
is provided as an electrically conductive material on the first layer. It an advantage
that the antenna is provided on the first layer of the printed circuit board, as this
means that the antenna can be short, such as shorter than the typical length of an
antenna in a hearing aid, such as in a BTE hearing aid. Typically and in prior art
the antenna is placed outside the printed circuit board, such as on the walls of the
housing, on a cover element, attached to a wall and/or just freely floating in the
housing, i.e. not being attached.
[0016] The hearing aid comprising a polarization element configured for forming the polarization
of the antenna, where the polarization element is provided on a flexible printed circuit
board, where the flexible printed circuit board comprises at least a first flexible
printed circuit board. It is an advantage that due to the polarization element, the
polarization of the antenna is configured to be formed or controlled or improved thereby
providing ear-to-ear (E2E) capabilities of the hearing aid.
[0017] The flexible printed circuit board is configured to be retro fitted in the hearing
aid after the actual manufacturing of the hearing aid. Alternatively, the flexible
printed circuit board can be provided in the hearing aid when the hearing aid is manufactured.
[0018] It is an advantage that the flexible printed circuit board comprising the polarization
element is configured to be retro-fitted in the hearing aid, as this provides for
changing or upgrading a standard hearing aid to a high-end or higher-end hearing aid
in an easy way.
[0019] The hearing aid comprises a wireless communication unit for wireless communication.
The wireless communication, or radio, may be arranged on the printed circuit board.
[0020] According to a further aspect of the invention, a binaural hearing aid system is
disclosed comprising a first and a second hearing aid as herein disclosed. Thus the
first and/or second hearing aid may be a hearing aid as disclosed above.
[0021] Thus it is an advantage that the polarization of the antenna can be formed or controlled
or directed, for example such that it is higher in an orthogonal direction or normal
to the head of the user or to the surface of the head of the user. The polarization
should be formed such that it improves the wireless communication between for example
two hearing aids arranged in both ears of the user. The correct polarization of the
antenna, e.g. a polarization which is higher in an orthogonal direction to the surface
of the head of the user, is an advantage as this is optimal to excite a strong surface
wave, i.e. electromagnetic wave, along the body, such as along the face of the user,
such as to the other ear of the user.
[0022] The wireless communication between two hearing aids is an advantage as the hearing
aids can communicate together, and such that each hearing aid does not need to be
adjusted manually, but can be adjusted automatically due to the wireless communication
with the hearing aid in the other ear. For example if the user turns his head, for
example when he is in a conversation with another person, the ear pointing away from
the sound source, e.g. the conversation partner, will receive less sound, and this
ear will thus hear less. Normally the user will then turn up the volume of this hearing
aid. However with the ear-to-ear technology the two hearing aids communicate wirelessly
with each other and can automatically turn up and down the volume when needed.
[0023] The correct or optimal polarization of the antenna provided by the polarization element
in the hearing aid(s) thus improves this wireless ear-to-ear communication between
the hearing aids.
[0024] The polarization of the antenna corresponds or defines or determines the direction
of the electric field or E-field.
[0025] The antenna is for emission and/or reception of an electromagnetic field being interconnected
with one of the one or more wireless communication units.
[0026] The antenna may be an electric antenna. The antenna may be a monopole antenna.
[0027] The antenna may be a dipole antenna. The antenna may be a resonant antenna. The antenna
may be a quarter-wave monopole antenna etc.
[0028] Thus it is an advantage that the antenna may be short, such as shorter than a loop
antenna. When the antenna is short, the antenna does not require much space in the
hearing aid and thus there are more options and flexibility with regards to the arrangement
of the antenna and the relative arrangement of first antenna and the other components.
[0029] The antenna may be configured to have a first radiation pattern.
[0030] The near field pattern for the antenna may be a TM polarized near field. The first
radiation pattern may be dominated by the E-field, so that a primary part of the overall
electromagnetic field, such as more than 75%, such as more than 80%, such as more
than 85%, such as more than 90% of the overall electromagnetic field, is contributed
by the E-field.
[0031] The antenna may be a 2.4 GHz antenna. The antenna may be configured for radiation
in a first frequency range. A second antenna may be provided, e.g. a magnetic antenna,
and the second antenna may be configured for radiation in a second frequency range.
[0032] The antenna may be configured to operate in the first frequency range, such as at
a frequency above 800 MHz, such as at a frequency above 1 GHz, such as at a frequency
of 2.4 GHz, such as at a frequency between 1.5 GHz and 3 GHz, during use. Thus, the
antenna may be configured for operation in ISM frequency band. The antenna may be
any antenna capable of operating at these frequencies, and the antenna may thus be
a resonant antenna, such as monopole antenna, such as a dipole antenna, etc. The resonant
antenna may have a length of lambda/4 or any multiple thereof, lambda being the wavelength
corresponding to the emitted electromagnetic field.
[0033] In present day communication systems, numerous different communication systems communicate
at or about 2.4 GHz, and thus there is also a significant noise in the frequency range
at or about 2.4 GHz. It is an advantage of the present invention that for some applications
for which the noise may be acceptable, for example for data communication, the antenna,
such as an electrical antenna may be used. For other applications, in which a high
noise level may impact the transmission significantly, a second antenna, such as a
magnetic antenna may be used. For example, the second antenna may be used for streaming
of audio.
[0034] The antenna may be configured for data communication at a first bit rate. In one
or more embodiments, a second antenna may be provided and the second antenna may be
configured for data communication at a second bit rate, the second bit rate being
larger than the first bit rate, such as by a factor 10, such as by a factor 30, a
factor 50, a factor 100, etc.
[0035] To improve the polarization of the antenna a polarization element is provided on
a flexible printed circuit board.
[0036] This means that there will be at least some currents induced on the polarization
element, and these currents have a direction between a first side and a second side
of the hearing aid device in an E2E direction. The PCB antenna is placed so that it
has current going in a non-E2E direction from a first end to an opposite second end,
since otherwise the antenna cannot have the desired length. Thus the E2E current may
be orthogonal relative to the direction of the antenna on the printed circuit board.
This is an improvement compared to just having the antenna by itself, because the
antenna by itself is placed in a plane, which has an orientation that means that the
electric field transmitted by the antenna for the most part will be in the skin of
the user, such as parallel to the surface of the user's head.
[0037] However, with a polarization element forming the polarization of the antenna, where
the polarization element is provided on the flexible printed circuit board, the electric
field can be oriented or directed or turned so that it becomes more orthogonal to
the surface, and thus skin, of the user's head. This is advantageous, because skin
has many charges which will attenuate the electric field if it is oscillating in the
surface skin of the user as it travels along the body and face.
[0038] The hearing aid or housing may comprise a first side and a second side, where the
first side and the second may be arranged opposite each other. The first side and
the second side may be arranged in an E2E direction when the hearing aid is worn by
the user. The hearing aid or housing may comprise a first end and a second end, where
the first end and the second end may be arranged opposite each other. The first end
and the second end may be arranged in a non-E2E direction when the hearing aid is
worn by the user. The E2E direction and the non-E2E direction may be orthogonal relative
to each other, such as substantially orthogonal, such as orthogonal within 20 degrees,
or within 10 degrees, or within 5 degrees. The first and the second side may be orthogonal
relative to the first and the second end, such as substantially orthogonal, such as
orthogonal within 20 degrees, or within 10 degrees, or within 5 degrees.
[0039] The hearing aid may be a Behind-The-Ear (BTE) hearing aid.
[0040] The hearing aid may comprise the printed circuit board having a first board surface
and a second board surface. The second board surface may be parallel to the first
board surface.
[0041] The hearing aid may comprise the flexible printed circuit board, also denoted flexible
carrier. The flexible printed circuit board may have a thickness in the range from
5 µm to 1,000 µm. The flexible printed circuit board may be a sheet. In an exemplary
electrical assembly, the flexible printed circuit board has a thickness in the range
from 12 µm to 600 µm, such as 50 µm, 100 µm, 200 µm, 300 µm, 400 µm, 500 µm or any
ranges therebetween. The flexible printed circuit board may have a first flexfilm
surface and a second flexfilm surface.
[0042] The electrically conducting material may be solder material such as a solder alloy,
e.g. comprising one or more of zinc, tin, silver, copper and lead.
[0043] The diameter at the first end and/or second end of the hearing aid is typically less
than 7 mm. The distance between the first end and the second end of the hearing aid
is typically also 7 mm
[0044] A printed circuit board may be provided in the hearing aid. The antenna may be connected
to the circuit board with a wire. The circuit board may have a matching circuit, a
balun and a radio, such as a wireless communication unit.
[0045] The polarization element can be connected to ground or it can be floating, i.e. not
connected to ground.
[0046] The hearing aid may comprise a battery. The battery may have a first side and a second
side. The battery may be provided at the second end of the hearing aid.
[0047] The battery may be a flat battery, such as a button shaped battery. The battery may
be circular. The battery may be a disk-shaped battery.
[0048] The hearing aid may be any hearing aid, such as a hearing aid of the in-the-ear type,
such as in-the-canal type, such as completely-in-the-canal type of hearing aid, etc.,
a hearing aid of the behind-the-ear type, of the receiver-in-the-ear type of hearing
aid, etc.
[0049] One or more wireless communications unit(s) are configured for wireless data communication,
and in this respect interconnected with the antenna for emission and reception of
an electromagnetic field. Each of the one or more wireless communication units may
comprise a transmitter, a receiver, a transmitter-receiver pair, such as a transceiver,
a radio unit, etc. The one or more wireless communication units 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, RF communication protocols, magnetic induction protocols, etc. The one
or more wireless communication units may be configured for communication using same
communication protocols, or same type of communication protocols, or the one or more
wireless communication units may be configured for communication using different communication
protocols.
[0050] The processing unit may be provided on a printed circuit board.
[0051] The term sound and/or the term acoustic output may be understood to be an audio signal.
Thus the microphone may be configured to receive sound or an audio signal. The output
transducer may be configured to provide or transmit an acoustic output or a processed
audio signal, such as the processed audio signal provided by the processing unit.
The acoustic output or processed audio signal may be provided or transmitted to an
ear of the user wearing the hearing aid during use.
[0052] In some embodiments the polarization element provides that the polarization of the
antenna is higher in an orthogonal direction to a surface of a user's head than in
a direction parallel to the surface of the user's head, when the hearing aid is arranged
in an ear of the user during use of the hearing aid.
[0053] Thus it is an advantage that the polarization of the antenna is higher in an orthogonal
direction or normal to the head of the user or to the surface of the head of the user
as this improves the wireless communication between for example two hearing aids arranged
in both ears of the user. The orthogonal polarization of the antenna is an advantage
as this is optimal to excite a strong surface wave, i.e. electromagnetic wave, along
the body, such as along the face of the user, such as to the other ear of the user.
[0054] Thus the polarization of the antenna is primarily, mainly or substantially orthogonal
or normal to the surface of the user's head. The polarization of the antenna is orthogonal
to the surface of the head such as 10 degrees from orthogonal, such as 15 degrees
orthogonal, such as 20 degrees orthogonal, such as 25 degrees orthogonal, such as
30 degrees orthogonal etc.
[0055] In some embodiments the polarization element comprises an electrically conductive
material. Thus it is an advantage that the polarization element may be provided as
an electrically conductive material. The electrically conducting material may be an
electrically conductive metal, such as cobber, and/or another suitable material which
is electrically conductive and can form the polarization of the antenna. The electrically
conductive material may be in the form of a metallic sheet or surface.
[0056] In some embodiments the electrically conductive material(s) is/are a conductive trace.
The conductive trace may be a wire. The conductive trace may be made of a metal, for
example cobber and/or alloy comprising cobber. The antenna and/or the polarization
element may be made of or comprise an electrically conductive material, such as a
conductive trace. Thus the antenna and/or the polarization element may be made of
a metal, such as cobber.
[0057] In some embodiments the hearing aid comprises a housing with one or more walls, and
wherein the flexible printed circuit board is attached and/or mounted on at least
a part of at least one of the one or more walls. The flexible printed circuit board
may be attached or mounted on the inside or internal face or surface of the one or
more walls.
[0058] In some embodiments the printed circuit board comprises a first pad, and wherein
the polarization element comprises a first end, and wherein the first end is interconnected
with the first pad. The first end of the polarization element may be termed a terminal,
such as a first terminal. The interconnection may be a connection and/or a mounting
and/or a soldering. As the printed circuit board and/or a part and/or layer of the
printed circuit board functions as ground (potential), the polarization element will
be connected to ground when connected to the printed circuit board at this first pad.
[0059] In some embodiments the printed circuit board comprises a second pad, and/or wherein
the polarization element comprises a second end.
[0060] In some embodiments the second end of the polarization element is interconnected
with the second pad. The interconnection may be a connection and/or a mounting and/or
a soldering. As the printed circuit board and/or a part and/or layer of the printed
circuit board functions as ground (potential), the polarization element will be connected
to ground when connected to the printed circuit board at this second pad. If the first
end of the polarization element is also interconnected with the second pad of the
printed circuit board, the flexible printed circuit board may extend all the way around
the housing from the first pad to the second pad of the printed circuit board, e.g.
forming a closed flexible printed circuit board, and this provides a long polarization
element which can provide a high current in an E2E direction, i.e. a current extending
across the hearing aid device from a first side of the hearing aid, or hearing aid
housing, to a second opposite side of the hearing aid, or hearing aid housing. The
PCB antenna is placed so that it has current going in a non-E2E direction from a first
end to an opposite second end, since otherwise the antenna cannot have the desired
length. Thus the E2E current may be orthogonal relative to the direction of the antenna
on the printed circuit board.
[0061] In some embodiments the flexible printed circuit board comprises a second flexible
printed circuit board, and wherein the second end of the polarization element on the
first flexible printed circuit board is arranged proximate to a second end of the
polarization element on the second flexible printed circuit board to provide a capacitive
coupling. The first and the second flexible printed circuits boards may be arranged
on opposite walls of the housing and/or on the same wall of the housing. The second
end of the polarization element on the first flexible printed circuit board is arranged
proximate to a second end of the polarization element on the second flexible printed
circuit board, where proximate may be such as opposite, such as exactly opposite,
or such as displaced relative to each other along a line in a longitudinal direction
of the housing. The capacitive coupling is thus between the second ends of the polarization
elements, whereby the signal or current may jump from the second end of the polarization
element of first flexible printed circuit board to the second end of the polarization
element of the second flexible printed circuit board, and thereby providing the same
function as a closed flexible printed circuit board, which provides a long polarization
element which can provide a high current in an E2E direction, i.e. a current extending
across the hearing aid device from a first side of the hearing aid, or hearing aid
housing, to a second opposite side of the hearing aid, or hearing aid housing. The
PCB antenna is placed so that it has current going in a non-E2E direction from a first
end to an opposite second end, since otherwise the antenna cannot have the desired
length. Thus the E2E current may be orthogonal relative to the direction of the antenna
on the printed circuit board. A closed flexible printed circuit board may be implemented
as disclosed in the previous embodiment, where the first end of the polarization element
is interconnected with the first pad of the printed circuit board, and where the second
end of the polarization element is interconnected with the second pad of the printed
circuit board.
[0062] It is an advantage of the present embodiment, i.e. where the flexible printed circuit
board comprises a second flexible printed circuit board, and wherein the second end
of the polarization element on the first flexible printed circuit board is arranged
proximate to a second end of the polarization element on the second flexible printed
circuit board to provide a capacitive coupling, that it may be easier to mount two
smaller flexible printed circuit boards in the hearing aid housing than one larger
and/or longer flexible printed circuit board.
[0063] In some embodiments the flexible printed circuit board comprising the polarization
element is configured to be retro-fitted to the hearing aid and/or housing. Thus it
is an advantage that the flexible printed circuit board can be retro-fitted, thereby
upgrading a standard hearing aid to a high-end or higher-end hearing aid with improved
polarization of the antenna and thereby ear-to-ear capabilities etc.
[0064] In some embodiments the antenna has a longitudinal extension in a first direction.
Typically the antenna currents will be in a non-ear-to-ear direction, otherwise the
antenna cannot have the desired long length along the printed circuit board.
[0065] In some embodiments the first direction of the longitudinal extension of the antenna
is parallel to a longitudinal extension of the printed circuit board.
[0066] In some embodiments the first direction of the longitudinal extension of the antenna
is in a plane parallel to a longitudinal extension of the hearing aid housing.
[0067] In some embodiments the polarization element has a longitudinal extension in a second
direction and/or third direction.
[0068] In some embodiments the first direction of the longitudinal extension of the antenna
is in a plane normal to the second direction and/or third direction of the polarization.
element. In a plane normal to may means substantially normal, such as normal within
20 degrees, 15 degrees, 10 degrees, 5 degrees etc. However, the first direction and/or
the second direction and/or the third direction can be non-normal or non-orthogonal
to each other, such as 30 degrees, 45 degrees, 60 degrees etc.
[0069] In some embodiments a first end of the antenna is connected with the first end of
the polarization element thereby extending a functional length of the antenna.
[0070] The antenna may be connected such as interconnected or mounted or soldered to the
polarization element. As both the polarization element and the antenna may be made
of an electrically conductive material, the functional or actual length of the antenna
is extended when the antenna is connected with the polarization element. It is an
advantage that the antenna is as big or long as possible as the antenna will then
cover a greater area where it can pick up or detect signals, such as electrical signals.
It is an advantage that the position of the high current on the antenna can be controlled
as this can also improve the polarization of the antenna. When the antenna is placed
on a printed circuit board, the high current will typically be placed in an undesired
position as the longitudinal extension of the antenna is typically in a direction
parallel to the head of the user. If the antenna is extended by connecting it with
the polarization element, the position of the high current on the antenna can be changed
and thereby improved to be on the part of the extended antenna which is orthogonal
to the head of the user. Thus it is advantage that the antenna can be extended and
the polarization of the antenna can be controlled and improved.
[0071] In some embodiments the walls of the housing comprises an inner surface having an
area, and wherein the flexible printed circuit board covers more than 20% of the area
of the inner surface of the hearing aid, such as more than 30%, 40%, 50%, 60%, 70%,
80%, or 90%. The flexible printed circuit board may cover the whole area of the inner
surface of the hearing aid. The flexible printed circuit board may covers less than
20%, such as less than 5%, or 10% of the inner surface of the hearing aid. The inner
surface may be the inner surface of the hearing aid housing.
[0072] In some embodiments the antenna comprises a first end and a second end, and wherein
the first end of the antenna may be connected to the polarization element.
[0073] In some embodiments the antenna has a longitudinal extension in a first direction,
for example a non-E2E direction from a first end of the hearing aid housing to a second
end of the hearing aid housing.
[0074] The antenna may have a longitudinal extension in a first direction. Thus, the antenna
may have an overall longitudinal extension in a first direction. The direction may
indicate a line or path along which the antenna is extending. For example, the overall
length of the antenna may be larger than the overall width of the antenna indicating
a longitudinal extension in the lengthwise direction.
[0075] Thus, for example, the antenna may comprise a first antenna element extending along
a plane normal to the first end of the hearing aid. The first antenna element may
extend along a plane parallel to a first axis. The first axis may extend from the
first end of the hearing aid to the second end of the hearing aid. The antenna may
comprise a second antenna element extending along a plane parallel to the first end
of the hearing aid. The second antenna element may extend along a plane normal to
the first axis.
[0076] It is an advantage that due to the polarization element, the polarization of the
antenna can be formed to be higher in an orthogonal direction to a surface of the
user's head than in a direction parallel to the surface of the user's head, when the
hearing aid is arranged in an ear of the user during use of the hearing aid. This
improves the wireless ear-to-ear communication between the ears of the user. If no
polarization element is provided in the hearing aid, the polarization of the antenna
would be mainly in a direction parallel to the surface of the user's head, when the
hearing aid is arranged in the ear of the user during use, and this would not improve
the wireless ear-to-ear communication between the ears of the user.
[0077] In some embodiments the hearing aid comprises a printed circuit board, where the
printed circuit board comprises a ground plane.
[0078] The hearing aid may comprise hearing aid electronic components including the processing
unit or signal processor. The hearing aid electronic components may be provided on
a printed circuit board. The one or more wireless communication units or radios may
be arranged on the printed circuit board.
[0079] The printed circuit board may be arranged between the first end and the second end
of the hearing aid. The printed circuit board may be arranged in the first end of
the hearing aid. The printed circuit board may be arranged in the second end of the
hearing aid.
[0080] Typically there is no ground plane in a hearing aid, as a ground plane may be a conducting
plane of infinite area or an area which is at least five wavelengths wide and five
wavelengths long. However, a layer of the printed circuit board may work as or have
the function of a ground plane. Thus the ground plane for the antenna may be whatever
structure that the ground connection from the balun is connected to.
[0081] In some embodiments the antenna is connected to the ground plane of the circuit board.
[0082] In some embodiments the polarization element is connected to the ground plane of
the circuit board.
[0083] Thus the polarization element can be connected to ground instead of just being floating,
i.e. with no galvanic connection to anything else.
[0084] Alternatively, the antenna is not connected to the polarization element. Alternatively
and/or additionally the second end of the antenna is connected to the polarization
element. For example both the first end of the antenna and the second end of the antenna
is connected to the polarization element.
[0085] In some embodiments the antenna is placed on a layer of the printed circuit board
(PCB). The antenna may be implemented as an electrically conductive material, such
as a copper trace, interconnected with the radio via matching components. The received/emitted
electro magnetic field has a first polarization. A flexible printed circuit board
also called a flex film can be placed within the housing of the hearing aid. The flexible
printed circuit board may have a copper trace which functions as a polarization element.
When placed in the housing the polarization of the antenna will change, because of
the presence of the polarization element on the flexible printed circuit board. An
end of the polarization element on the flexible printed circuit board can be soldered
to the PCB so that there will be a connection to a ground potential, i.e. the ground
potential layer of the PCB. With the flexible printed circuit board the electric field
of the antenna will be polarized more parallel to a surface of the user's head than
orthogonal to the surface of the head. It is advantage of flexible printed circuit
board with the polarization element that it is possible to provide upgradeable hearing
aids by retro-fitting the flexible printed circuit board in the hearing aid. The antenna
on the PCB is simple to produce and cheap and can thus be provided in all produced
devices. For higher end products the flexible printed circuit board with the polarization
element can be added in the hearing aid to give E2E capabilities, i.e. obtaining better
directionality etc.
[0086] In some embodiments a first flexible printed circuit board and a second flexible
printed circuit board can be placed in the housing. Both flexible printed circuit
boards have a polarization element, for example in the form of an electrically conductive
material, such as a copper trace. The first ends of the traces can be interconnected
with ground. The second ends of the traces can be placed proximate each other so there
can be a capacitive coupling between them.
[0087] In some embodiments a single flexible printed circuit board with a polarization element,
such as a copper trace is provided. Both the first end and the second end of the trace
can be soldered to the PCB and thereby connected to a ground. The flexible printed
circuit board allow for a long polarization element in the form of the trace that
can give a high current of the antenna in an E2E direction, i.e. a current going across
the hearing aid device from a first side to a second opposite side. The PCB antenna
is placed in the hearing aid in a way where it has currents going in a non E2E direction,
since otherwise the antenna cannot have the desired length. With the polarization
element in the form of the trace provided on the flexible printed circuit board, the
polarization of the antenna can be formed to be in the desired direction.
[0088] In some embodiments an extension of the length of the antenna is provided, which
make the antenna more effective. The antenna on the PCB can have a length which is
a quarter of a wavelength whereby the antenna can function alone. The polarization
element in the form of a trace on the flexible printed circuit board can be three
quarters of a wavelength, and when the end of the antenna is connected with the end
of the polarization element, this provides a total functional length of the antenna
to be one wavelength, i.e. a sphere enclosing the PCB antenna alone is smaller than
the sphere enclosing the antenna and flexible printed circuit board trace. Thus the
end, such as the first end, of the PCB antenna may be soldered together with the end,
such as the first end, of the flex film antenna.
[0089] An advantage of the hearing aid(s) as disclosed herein is that an improved wireless
ear-to-ear communication may be achieved for most head sizes, shapes and amount of
hair. Human heads and human ears vary in size and shape and also the amount of hair
varies from person to person. Hearing aids adapted for wireless communications may
be susceptible to impairments of for example the ear-to-ear communication due to e.g.
the head of the user. Radio waves from a hearing aid at one side may have to travel
through or around the head in order to reach the hearing aid at the other ear. Therefore,
the human head may be perceived as an obstacle to the ear-to-ear communication. It
is an advantage of the present invention that the polarization of the antenna as provided
in the hearing aid improves the ear-to-ear communication.
[0090] In the following the invention is described primarily with reference to a hearing
aid, such as a binaural hearing aid. It is however envisaged that the disclosed features
and embodiments may be used in combination with any aspect of the invention.
[0091] The present invention relates to different aspects including the hearing aid described
above and in the following, and corresponding methods, devices, systems, uses and/or
product means, each yielding one or more of the benefits and advantages described
in connection with the first mentioned aspect, and each having one or more embodiments
corresponding to the embodiments described in connection with the first mentioned
aspect and/or disclosed in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0092] The above and other features and advantages will become readily apparent to those
skilled in the art by the following detailed description of exemplary embodiments
thereof with reference to the attached drawings, in which:
Fig. 1 schematically illustrates an exemplary hearing aid.
Fig. 2 schematically illustrates an exemplary hearing aid with a single flexible printed
circuit board.
Fig. 3 schematically illustrates an exemplary hearing aid with two flexible printed
circuit boards.
Fig. 4 schematically illustrates an exemplary hearing aid with a single flexible printed
circuit board extending from a first pad of the printed circuit board to a second
pad of the printed circuit board.
Fig. 5 schematically illustrates an exemplary hearing aid with an extended antenna.
DETAILED DESCRIPTION
[0093] Various embodiments are described hereinafter with reference to the figures. 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. It should also
be noted that the figures are only intended to facilitate the description of the embodiments.
They are not intended as an exhaustive description of the claimed invention or as
a limitation on the scope of the claimed invention. In addition, an illustrated embodiment
needs not have all the aspects or advantages shown. An aspect or an advantage described
in conjunction with a particular embodiment is not necessarily limited to that embodiment
and can be practiced in any other embodiments even if not so illustrated, or if not
so explicitly described.
[0094] Throughout, the same reference numerals are used for identical or corresponding parts.
[0095] As used herein, the term "antenna" refers to an electrical or magnetic device which
converts electric or magnetic power into radio waves. An electric antenna may comprise
an electrically conductive material connected to e.g. a wireless communications unit,
such as a radio chip, a receiver or a transmitter. A magnetic antenna, such as a magnetic
loop antenna, may comprise a coil of electrically conductive material wound around
a core of magnetic material.
[0096] Fig. 1 schematically illustrates an exemplary hearing aid 2. The hearing aid 2 comprises
a microphone 4 configured to receive sound, a processing unit 6 configured to provide
a processed audio signal for compensating a hearing loss of a user, a printed circuit
board (not shown) comprising a first layer (not shown), an antenna 12 provided as
an electrically conductive material on the first layer, a wireless communication unit
14 for wireless communication, and a polarization element (not shown) configured for
forming the polarization of the antenna 12. The hearing aid further comprises a output
transducer or receiver 20, which may be arranged in the hearing aid housing or outside
the hearing aid housing, such as in the ear of the user, while the hearing aid housing
is configured to be arranged behind the ear of the user.
[0097] Fig. 2 schematically illustrates an exemplary hearing aid 2. The hearing aid comprises
a microphone (not shown) configured to receive sound, a processing unit (not shown)
configured to provide a processed audio signal for compensating a hearing loss of
a user. The hearing aid 2 comprises a printed circuit board 8 comprising a first layer
10. An antenna 12 is provided as an electrically conductive material on the first
layer 10. A wireless communication unit 14 or radio for wireless communication is
provided, e.g. on the printed circuit board 8. The hearing aid 2 comprises a polarization
element 16 configured for forming the polarization of the antenna 12. The polarization
element 16 is provided on a flexible printed circuit board 18, and the flexible printed
circuit board 18 comprises at least a first flexible printed circuit board 18a.
[0098] The hearing aid 2 comprises a housing 24 with a number of walls 22, and the flexible
printed circuit board 18 is mounted on a part of two 22a, 22b of the one or more walls
22.
[0099] The printed circuit board 8 comprises a first pad 26. The polarization element 16
comprises a first end 28. The first end 28 of the polarization element 16 is interconnected
with the first pad 26 of the PCB 8.
[0100] Thus the antenna 12 is placed on a layer 10 of the PCB 8. The antenna 12 may be a
copper trace interconnected with the radio 14 via matching components. The received/emitted
electro magnetic field of the antenna has a first polarization. The flexible printed
circuit board 18 is placed within the housing 24 of the hearing aid 2. The flexible
printed circuit board 18 may have a copper trace providing a polarization element
16. When the flexible printed circuit board 18 is placed in the housing 24 the polarization
of the antenna 12 will change, because of the presence of the polarization element
16 on the flexible printed circuit board 18. A first end 28 of the trace providing
the polarization element 16 on the flexible printed circuit board 18 can be soldered
to a first pad 26 of the PCB 8 so that there will be a connection to a ground potential,
i.e. the ground potential layer of the PCB 8. With the flexible printed circuit board
18 comprising the polarization element 16 the electric field of the antenna 12 will
be polarized more parallel to a surface of the head than orthogonal to the surface
of the head.
[0101] The antenna 12 has a longitudinal extension in a first direction along a first axis
40. The first direction of the longitudinal extension of the antenna 12 is parallel
to a longitudinal extension of the printed circuit board 8. The first direction of
the longitudinal extension of the antenna 12 is in a plane parallel to a longitudinal
extension of the hearing aid housing 24. The polarization element 16 has a longitudinal
extension in a second direction and/or third direction, which may be normal to the
first direction along the axis 40.
[0102] The polarization element 16 can give a high current of the antenna 12 in an E2E direction
50, i.e. a current going across the hearing aid device or housing 24 from a first
side 52 to a second opposite side 54. The PCB antenna 12 is placed so that it has
current going in a non-E2E direction 40 from a first end 42 to an opposite second
end 44, since otherwise the antenna 12 cannot have the desired length. Thus the E2E
current is orthogonal relative to the direction of the antenna on the printed circuit
board.
[0103] The hearing aid 2 may comprise a battery 56. The battery may be arranged in a second
end 44 of the hearing aid housing 24.
[0104] The hearing aid may comprise a coupling element 58. If the hearing aid is a BTE hearing
aid, the output transducer is arranged in the behind-the-ear part of the hearing aid,
e.g. the housing 24, and the coupling element 58 is an acoustic coupling element directing
the sound into the ear of the user. If the hearing aid is a receiver-in-the-canal
(RIE), the output transducer is arranged in the ear of the user, and the coupling
element 58 comprises wires (not shown) to the output transducer. The coupling element
58 may be arranged in a first end 42 of the hearing aid housing 24.
[0105] Fig. 3 schematically illustrates an exemplary hearing aid 2. The hearing aid 2 comprises
a printed circuit board 8 comprising a first layer 10. An antenna 12 is provided as
an electrically conductive material on the first layer 10. A wireless communication
unit 14 or radio for wireless communication is provided, e.g. on the printed circuit
board 8. The hearing aid 2 comprises a first flexible printed circuit board 18a and
a second flexible printed circuit board 18b which are placed in a housing 24 of the
hearing aid 2. Both flexible printed circuit boards 18a, 18b have a polarization element
16a, 16b in the form of an electrically conductive trace. The first ends 28, 30 of
the polarization elements 16a, 16b may be can be soldered to a first pad 26 and to
a second pad 32, respectively, of the PCB 8 so that there will be a connection to
a ground potential, i.e. the ground potential layer of the PCB 8. The other ends 34,
36 of the polarizations elements 16a, 16b can be placed proximate each other so there
can be a capacitive coupling between them. The capacitive coupling between the polarization
elements 16a, 16b on the flexible printed circuit boards 18a, 18b allows for a functional
long trace that can give a high current of the antenna 12 in an E2E direction 50,
i.e. a current going across the hearing aid device or housing 24 from a first side
52 to a second opposite side 54. The PCB antenna 12 is placed so that it has current
going in a non-E2E direction 40 from a first end 42 to an opposite second end 44,
since otherwise the antenna 12 cannot have the desired length. Thus the E2E current
is orthogonal relative to the direction of the antenna on the printed circuit board.
[0106] Fig. 4 schematically illustrates an exemplary hearing aid 2. The hearing aid 2 comprises
a printed circuit board 8 comprising a first layer 10. An antenna 12 is provided as
an electrically conductive material on the first layer 10. A wireless communication
unit 14 or radio for wireless communication is provided, e.g. on the printed circuit
board 8. The hearing aid 2 comprises a flexible printed circuit board 18 comprising
a polarization element 16 having a first end 28 soldered to a first pad 26 of the
printed circuit board 8. The polarization element 16 comprises a second end 34 soldered
to a second pad 32 of the printed circuit board 8. Thus both ends 28, 34 of the trace
forming the polarization element 18 can be soldered to the PCB and thereby connected
to a ground. The flexible printed circuit board 18 allows for a long trace that can
give a high current of the antenna 12 in an E2E direction 50, i.e. a current going
across the hearing aid device or housing 24 from a first side 52 to a second opposite
side 54. The PCB antenna 12 is placed so that it has current going in a non-E2E direction
40 from a first end 42 to an opposite second end 44, since otherwise the antenna 12
cannot have the desired length. Thus the E2E current is orthogonal relative to the
direction of the antenna on the printed circuit board.
[0107] Fig. 5 schematically illustrates an exemplary hearing aid 2. The hearing aid 2 comprises
a printed circuit board 8 comprising a first layer 10. An antenna 12 is provided as
an electrically conductive material on the first layer 10. A wireless communication
unit 14 or radio for wireless communication is provided, e.g. on the printed circuit
board 8. The hearing aid 2 comprises a flexible printed circuit board 18 comprising
a polarization element 16 having a first end 28 connected, such as soldered, to a
second end 12b of the antenna 12. The first end 12a of the antenna is connected to
the radio 14. The polarization element 16 comprises a second end 34. Thus as the antenna
12 and the polarization element 16 are connected, this provides an extension of the
length of the antenna 12, thereby making the antenna 12 more effective. The antenna
12 on the PCB 8 can have a length of one quarter of a wavelength thereby functioning
alone. The polarization element 16 on the flexible printed circuit board 18 film can
be three quarters of a wavelength giving a total functional length of the antenna
12 to be one wavelength, i.e. a sphere enclosing the PCB antenna 12 alone is smaller
than the sphere enclosing the antenna 12 and polarization element 16.
[0108] Although particular features have been shown and described, it will be understood
that they are not intended to limit the claimed invention, and it will be made obvious
to those skilled in the art that various changes and modifications may be made without
departing from the scope of the claimed invention. The specification and drawings
are, accordingly to be regarded in an illustrative rather than restrictive sense.
The claimed invention is intended to cover all alternatives, modifications and equivalents.
LIST OF REFERENCES
[0109]
- 2
- hearing aid
- 4
- microphone
- 6
- processing unit
- 8
- printed circuit board (PCB)
- 10
- first layer
- 12
- antenna
- 12a
- first end of antenna
- 12b
- second end of antenna
- 14
- wireless communication unit or radio
- 16
- polarization element
- 16a
- first polarization element
- 16b
- second polarization element
- 18
- flexible printed circuit board or flex film
- 18a
- first flexible printed circuit board
- 18b
- second flexible printed circuit board
- 20
- output transducer or receiver
- 22, 22a, 22b
- walls
- 24
- housing
- 26
- first pad of PCB
- 28
- first end of (first) polarization element
- 30
- first end of second polarization element
- 32
- second pad of PCB
- 34
- second end of (first) polarization element
- 36
- second end of second polarization element
- 40
- first axis/non-E2E direction
- 42
- first end of housing/hearing aid
- 44
- second end of housing/hearing aid
- 50
- E2E direction
- 52
- first side of housing/hearing aid
- 54
- second side of housing/hearing aid
- 56
- battery
- 58
- coupling element
1. A hearing aid comprising:
- a microphone configured to receive sound,
- a processing unit configured to provide a processed audio signal for compensating
a hearing loss of a user,
- a printed circuit board comprising a first layer,
- an antenna provided as an electrically conductive material on the first layer,
- a wireless communication unit for wireless communication,
- a polarization element configured for forming the polarization of the antenna, where
the polarization element is provided on a flexible printed circuit board, the flexible
printed circuit board comprises at least a first flexible printed circuit board.
2. Hearing aid according to any of the preceding claims, wherein the polarization element
provides that the polarization of the antenna is higher in an orthogonal direction
to a surface of a user's head than in a direction parallel to the surface of the user's
head, when the hearing aid is arranged in an ear of the user during use of the hearing
aid.
3. Hearing aid according to any of the preceding claims, wherein the polarization element
comprises an electrically conductive material.
4. Hearing aid according to any of the preceding claims, wherein the electrically conductive
material(s) is/are a conductive trace.
5. Hearing aid according to any of the preceding claims, wherein the hearing aid comprises
a housing with one or more walls, and wherein the flexible printed circuit board is
attached/mounted on at least a part of at least one of the one or more walls.
6. Hearing aid according to any of the preceding claims, wherein the printed circuit
board comprises a first pad, and wherein the polarization element comprises a first
end, and wherein the first end is interconnected with the first pad.
7. Hearing aid according to any of the preceding claims, wherein the printed circuit
board comprises a second pad, and/or wherein the polarization element comprises a
second end.
8. Hearing aid according to any of the preceding claims, wherein the second end is interconnected
with the second pad.
9. Hearing aid according to any of claims 1-7, wherein the flexible printed circuit board
comprises a second flexible printed circuit board, and wherein the second end of the
polarization element on the first flexible printed circuit board is arranged proximate
to a second end of the polarization element on the second flexible printed circuit
board to provide a capacitive coupling.
10. Hearing aid according to any of the preceding claims, wherein the flexible printed
circuit board comprising the polarization element is configured to be retro-fitted
to the hearing aid/housing.
11. Hearing aid according to any of the preceding claims, wherein the antenna has a longitudinal
extension in a first direction.
12. Hearing aid according to any of the preceding claims, wherein the first direction
of the longitudinal extension of the antenna is parallel to a longitudinal extension
of the printed circuit board.
13. Hearing aid according to any of the preceding claims, wherein the first direction
of the longitudinal extension of the antenna is in a plane parallel to a longitudinal
extension of the hearing aid housing.
14. Hearing aid according to any of the preceding claims, wherein the polarization element
has a longitudinal extension in a second direction and/or third direction.
15. Hearing aid according to any of the preceding claims, wherein a first end of the antenna
is connected with the first end of the polarization element thereby extending a functional
length of the antenna.